Management of GBS and patient outcomes
All cases with available therapy data (n = 70) except ten [13, 15, 23, 25, 26, 33, 35–37, 41] were treated with intravenous immunoglobulin (IVIG) (Table 1). Conversely, plasma exchange and steroid therapy were performed in ten (four of them received also IVIG) and two cases, respectively. In two patients, no therapy was given. Mechanical or non-invasive ventilation was implemented in 21.4% (15/70) and 7.1% (5/70) patients due to worsening of GBS or COVID-19, respectively. At further observation (n = 68), 72.1% (49/68) patients demonstrated clinical improvement with partial or complete remission, 10.3% (7/68) cases showed no improvement, 11.8% (8/68) still required critical care treatment, and 5.8% (4/68) died (Table 1).
Table 1 Summary of clinical findings, results of diagnostic investigations, and outcome in 73 GBS cases
Article Country Age Sex GBS clinical picture COVID-19 clinical picture Previous comorbidities GBS diagnosis Level of diagnostic certaintyb GBS variant
Days between COVID-19 symptoms and GBS onset Onset Disease course Autonomic disturbances Respiratory symptoms/failure Time to Nadira
Agosti et al. [5] Italy 68 M 5 days after LL weakness Bilateral facial palsy, progressive symmetric ascending flaccid tetraparesis, achilles tendon areflexia NA No NA Dry cough associated with fever, dysgeusia, and hyposmia Dyslipidemia, benign prostatic hypertrophy, hypertension, abdominal aortic aneurysm Clinical + CSF + electrophysiology 1 Pure motor
Alberti et al. [6] Italy 71 M 4 days after (no resolution of pneumonia) LL paraesthesia Ascendant weakness, flaccid tetraparesis, hypoesthesia and paraesthesia in the 4 limbs, generalized areflexia, dyspnea None Yes (concurrent pneumonia) 4 days after symptoms onset (24 h after the admission) Fever (low grade), dyspnea, pneumonia Hypertension, treated abdominal aortic aneurysm, treated lung cancer Clinical + CSF + electrophysiology 1 Classic sensorimotor
Arnaud et al. [7] France 64 M 23 days after Fast progressive LL weakness Generalized areflexia, severe flaccid proximal paraparesis, decreased proprioceptive length-dependent sensitivity and LL pinprick and light touch hypoesthesia None No 4 days after symptoms onset Fever, cough, diarrhea, dyspnea, severe interstitial pneumonia DM type 2 Clinical + CSF + electrophysiology 1 Classic sensorimotor
Assini et al. [8] Italy 55 M 20 days after Bilateral eyelid ptosis, dysphagia, dysphonia Masseter weakness, tongue protusion (bilateral hypoglossal nerve paralysis), UL and LL hyporeflexia without muscle weakness, soft palate elevation defect None Yes (concurrent pneumonia) NA Fever, anosmia, ageusia, cough, pneumonia NA Clinical + electrophysiology 2 Classic sensorimotor overlapping with Miller-Fisher
Assini et al. [8] Italy 60 M 20 days after Distal tetraparesis with right foot drop, autonomic disturbances UL and LL distal weakness, right foot drop, generalized areflexia Gastroplegia, paralytic ileus, loss of blood pressure control Yes (concurrent pneumonia) NA Fever, severe interstitial pneumonia NA Clinical + electrophysiology 2 Pure motor
Bigaut et al. [9] France 43 M 21 days after UL and LL paraesthesia, distal LL weakness Extension to midthigh and tips of the finger with ataxia, right peripheral facial nerve palsy, generalized areflexia None No 2 days after symptoms onset Cough, asthenia, myalgia in legs, followed by acute anosmia and ageusia with diarrhea, mild interstitial pneumonia NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Bigaut et al. [9] France 70 F 10 days after Acute proximal tetraparesis, distal forelimb and perioral paraesthesia Respiratory weakness, loss of ambulation None Yes 3 days after symptoms onset Anosmia, ageusia, diarrhea, asthenia, myalgia, moderate interstitial pneumonia Obesity Clinical + CSF + electrophysiology 1 Classic sensorimotor
Bracaglia et al. [10] Italy 66 F Unknown (due to asymptomatic infection) Acute proximal and distal tetraparesis, lumbar pain and distal tingling sensation Loss of ambulation, difficulty in speeching and swallowing, generalized areflexia None No NA Asymptomatic None Clinical + electrophysiology 2 Classic sensorimotor
Camdessanche et al. [11] France 64 M 11 days after UL and LL paraesthesia Ascendent weakness, flaccid tetraparesis, generalized areflexia, dysphagia None Yes 3 days after symptoms onset Fever (high grade), cough, pneumonia None Clinical + CSF + electrophysiology 1 Classic sensorimotor
Chan et al. [12] Canada 58 M 20 days after home isolation for suspected contact Bilateral facial weakness, dysarthria, feet paraesthesia, LL areflexia NA None No NA Asymptomatic, interstitial pneumonia None Clinical + CSF + electrophysiology 1 Bilateral facial palsy
with paraesthesia
Chan et al. [13] USA 68 M 18 days after Gait disturbance, hands and feet paraesthesia LL proximal weakness, absent vibratory and proprioceptive sense at the toes, UL hyporeflexia, LL areflexia, unsteady gait with inability to toe or heel walk, bilateral facial weakness, dysphagia, dysarthria, neck flexion weakness None No 8 days after the onset of symptoms Fever and upper respiratory symptoms NA Clinical + CSF 2 Classic sensorimotor
Chan et al. [13] USA 84 M 16 days after Hands and feet paraesthesia, progressive gait disturbance Bilateral facial weakness, progressive arm weakness, neuromuscular respiratory failure Yes (not specified autonomic dysfunction) Yes 25 days after the onset of symptoms Fever NA Clinical + CSF 2 Classic sensorimotor
Coen et al. [14] Switzerland 70 M 6 days after Paraparesis, distal allodynia Generalized areflexia Difficulties in voiding and constipation No NA Dry cough, myalgia, fatigue None Clinical + CSF + 0electrophysiology 1 Classic sensorimotor
Ebrahimzadeh et al. [15] Iran 46 M 18 days after Pain and numbness in distal LL and UL extremities, ascending weakness in legs Mild peripheral right facial nerve palsy, generalized areflexia None No 7 days after symptoms onset Low-grade fever, sore thorat, dry cough and mild dyspnea, bilateral interstitial pneumonia (concurrent with neurological symptoms) None Clinical + CSF + electrophysiology 1 Classic sensorimotor
Ebrahimzadeh et al. [15] Iran 65 M 10 days after Progressive ascending LL and UL extremities weakness and paraesthesia Proximal and distal UL and LL weakness, UL hyporeflexia and LL areflexia None No 14 days after symptoms onset History of COVID-19 (symptoms not specified), fine crackles in both lungs (concurrent with neurological symptoms) Hypertension Clinical + electrophysiology 2 Classic sensorimotor
El Otmani et al. [16] Morocco 70 F 3 days after Weakness and paraesthesia in the 4 limbs Tetraparesis, hypotonia, generalized areflexia, bilateral positive Lasègue sign None No NA Dry cough, pneumonia Rheumatoid arthritis Clinical + CSF + electrophysiology 1 Classic sensorimotor
Esteban Molina et al. [17] Spain 55 F 14 days after Paraesthesia and weakness in the 4 limbs Lumbar pain, dysphagia, tetraplegia, general areflexia, bilateral facial palsy, lingual and perioral paraesthesia None Yes 3 days after symptoms onset (48 h after the admission) Fever, dry cough and dyspnoea, pneumonia Dyslipidemia Clinical + CSF + electrophysiology 1 Classic sensorimotor
Farzi et al. [18] Iran 41 M 10 days after Paraesthesia of the feet Tetraparesis, areflexia at the LL and hyporeflexia at the UL, stocking-and-glove hypesthesia and reduced sense of vibration and position None No 7 days after symptoms onset Cough, dyspnea and fever DM type II Clinical + electrophysiology 2 Classic sensorimotor
Fernández–Domínguez et al. [19] Spain 74 F 15 days after Gait ataxia and generalized areflexia NA NA No NA Respiratory symptoms (not further detailed) Hypertension and follicular lymphoma Clinical + CSF 2 Miller Fisher variant
Finsterer et al. [20] India 20 M 5 days after NA NA NA NA NA NA NA Clinical + electrophysiology 2 NA
Frank et al. [21] Brazil 15 M > 5 days after Paraparesis, pain in the LL Rapidly progressive ascending tetraparesis, areflexia NA No NA Fever, intense sweating NA Clinical + electrophysiology 2 Classic sensorimotor
Gigli et al. [22] Italy 53 M NA Paraesthesia, gait ataxia NA NA NA NA Fever, diarrhea NA Clinical + CSF + electrophysiology 1 NA
Gutiérrez-Ortiz et al. [23] Spain 50 M 3 days after Vertical diplopia, perioral paraesthesia, gait ataxia Right internuclear ophthalmoparesis and right fascicular oculomotor palsy, ataxia, generalized areflexia None No NA Fever, cough, malaise, headache, low back pain, anosmia, ageusia Bronchial asthma Clinical + CSF 2 Miller Fisher variant
Gutiérrez-Ortiz et al. [23] Spain 39 M 3 days after Diplopia (bilateral abducens palsy) Generalized areflexia None No NA Diarrhea, low-grade fever None Clinical + CSF 2 Polyneuritis cranialis (GBS–Miller Fisher Interface)
Helbok et al. [24] Austria 68 M 14 days after Hypoaesthesia and paraesthesia in the LL, proximal weakness, areflexia, stand ataxia Ascending weakness, flaccid tetraparesis, generalized areflexia NA Yes 2 days after symptoms onset (24 h after the admission) Fever, dry cough, myalgia, anosmia and ageusia. None Clinical + CSF + electrophysiology 1 Classic sensorimotor
Hutchins et al. [25] USA 21 M 16 days after Right-sided facial numbness and weakness Bilateral facial palsy, severe dysarthria, bilateral LL weakness , bilateral UL paraesthesia, areflexia NA No 3 days after symptoms onset Fever, cough, dyspnoea, diarrhea, nausea, headache Hypertension, prediabetes, and class I obesity Clinical + CSF + electrophysiology 1 Bilateral facial palsy with paraesthesia
Juliao Caamaño et al. [26] Spain 61 M 10 days after Facial diplegia No progression None No 1 day after symptoms onset Fever and cough None Clinical + electrophysiology 3 Bilateral facial nerve palsy
Khalifa et al. [27] Kingdom of Saudi Arabia 11 M 20 days after Gait ataxia, areflexia and paraesthesia in the LL Gradual motor improvement, persistent hyporeflexia NA No NA Acute upper respiratory tract infection, low-grade fever, dry cough. NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Kilinc et al. [28] The Netherlands 50 M 24 days after Facial diplegia, symmetrical proximal weakness, paraesthesia of distal extremities, gait ataxia, areflexia Progression of limb weakness and inability to walk NA No 11 days after symptoms onset Dry cough None Clinical + electrophysiology 2 Classic sensorimotor
Lampe et al. [29] Germany 65 M 2 days after Acute right UL and LL weakness causing recurrent falls Right UL paresis, slight paraparesis more pronounced on the right side, generalized hyporeflexia None No 3 days after symptoms onset Fever and dry cough None Clinical + CSF + electrophysiology 1 Pure motor
Lantos et al. [30] USA 36 M 4 days after Opthalmoparesisa and hypoesthesia below knee Progressive ophthalmoparesis (including initial left III cranial nerve and eventual bilateral VI cranial nerve palsies), ataxia, and hyporeflexia None No NA Fever, chills, and myalgia None Clinical 3 Miller Fisher variant
Lascano et al. [31] Switzerland 52 F 15 days after (no resolution of pneumonia) Back pain, diarrhea, rapidly progressive tetraparesis, distal paraesthesia Worsening of proximal weakness (tetraplegia), generalized areflexia, ataxia Constipation, abdominal pain Yes 4 days after symptoms onset Dry cough, dysgeusia, cacosmia None Clinical + CSF + electrophysiology 1 Classic sensorimotor
Lascano et al. [31] Switzerland 63 F 7 days after (no resolution of pneumonia) Limb weakness, pain on the left calf Moderate tetraparesis, LL and left UL areflexia, distal hypoesthesia and paraesthesia None No 5 days after symptoms onset Dry cough, shivering, breathing difficulties, chest pain, odynophagia DM type 2 Clinical + electrophysiology 2 Classic sensorimotor
Lascano et al. [31] Switzerland 61 F 22 days after LL weakness, dizziness, dysphagia Moderate tetraparesis, bilateral facial palsy, lower limb allodynia, severe hypopallesthesia, areflexia (except for bicipital tendon reflexes) None Yes 4 days after symptoms onset Productive cough, headaches, fever, myalgia, diarrhea, nausea, vomiting, weight loss, recurrent episodes of transient loss of consciousness None Clinical + CSF + electrophysiology 1 Classic sensorimotor
Manganotti et al. [32] Italy 50 F 16 days after Diplopia and facial paraesthesia Ataxia, diplopia in vertical and lateral gaze, left upper arm dysmetria, generalized areflexia, mild lower facial defects, and mild hypoesthesia in the left mandibular and maxillary branch None Yes (concurrent pneumonia) NA Fever, cough, ageusia, bilateral pneumonia None Clinical + CSF 2 Miller Fisher variant
Manganotti et al. [33] Italy 72 M 18 days after Tetraparesis UL > LL, LL paraesthesia , generalized areflexia, facial weakness on the right side NA NA No NA Fever, dyspnea, hyposmia and ageusia NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Manganotti et al. [33] Italy 72 M 30 days after Tetraparesis LL > UL, paraesthesia, global areflexia NA NA No NA Fever, cough, dyspnea, hyposmia and ageusia NA Clinical + electrophysiology 1 Classic sensorimotor
Manganotti et al. [33] Italy 49 F 14 days after Ophthalmoplegia, limb ataxia, generalized areflexia, diplopia, facial hypoesthesia, facial weakness NA NA No NA Fever, cough, dyspnea, hyposmia and ageusia NA Clinical + CSF + electrophysiology 1 Miller Fisher variant
Manganotti et al. [33] Italy 94 M 33 days after LL weakness, generalized hyporeflexia NA NA No NA Fever, cough, gastrointestinal symptoms NA Clinical + electrophysiology 2 Classic sensorimotor
Manganotti et al. [33] Italy 76 M 22 days after Quadriparesis UL > LL, generalized areflexia, facial weakness, transient diplopia NA NA No NA Fever, cough, dysuria, hyposmia, ageusia NA Clinical + CSF + electrophysiology 1 Pure motor
Marta-Enguita et al. [34] Spain 76 F 8 days after Back pain and progressive tetraparesis with distal-onset paraesthesia Progressive with dysphagia and cranial nerves involvement, generalized areflexia NA Yes 10 days after symptom onset Cough and fever without dyspnea None Clinical 3 NA
Mozhdehipanah et al. [35] Iran 38 M 16 days after Progressive LL paraesthesia, facial diplegia, lobal areflexia Mild LL weakness , bulbar symptoms developed Blood pressure instability, tachycardia No 8 days after symptoms onset Upper respiratory infection (no further details) NA Clinical + CSF + electrophysiology 1 Bilateral facial palsy with paraesthesia
Mozhdehipanah et al. [35] Iran 14 F NA Ascending quadriparesis, UL hyporeflexia, LL areflexia, distal hypoesthesia, ataxia NA NA No NA Upper respiratory infection (no further details) NA Clinical + CSF 2 Classic sensorimotor
Mozhdehipanah et al. [35] Iran 44 F 26 days after Weakness of LL Tetraparesis, generalized areflexia, symmetrical hypoesthesia NA Yes NA Dry cough, fever, myalgia, progressive dyspnea COPD Clinical + CSF + electrophysiology 1 Classic sensorimotor
Mozhdehipanah et al. [35] Iran 66 F 30 days after Progressive UL and LL weakness, generalized areflexia, symmetrical hypoesthesia NA No No NA Fever, dry cough, severe myalgia DM, hypertension, and rheumatoid arthritis Clinical + CSF + electrophysiology 1 Classic sensorimotor
Naddaf et al. [36] USA 58 F 17 days after Progressive paraparesis, imbalance, severe lower thoracic pain without radiation Mild neck flexion weakness, mild/moderate distal UL  and proximal and distal LL  weakness, UL hyporeflexia, LL areflexia, moderately severe length-dependent sensory loss in the feet, ataxic gait None No NA Fever, dysgeusia without anosmia, bilateral interstitial pneumonia None Clinical + CSF + electrophysiology 1 Classic sensorimotor
Oguz-Akarsu et al. [37] Turkey 53 F Concurrent pneumonia Dysarthria, progressive LL weakness and numbness Ataxia, generalized areflexia None No NA Mild fever (37.5 °C), pneumonia None Clinical + electrophysiology 2 Classic sensorimotor
Ottaviani et al. [38] Italy 66 F 7 days after (concurrent pneumonia) Flaccid paraparesis, no sensory symptoms Progressively developed proximal weakness in all limbs, dysesthesia, and unilateral facial palsy, generalized areflexia NA Yes 13 days after symptoms onset Fever and cough, pneumonia NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Padroni et al. [39] Italy 70 F 23 days after UL and LL paraesthesia, gait difficulties, asthenia Ascendant weakness, tetraparesis, generalized areflexia None Yes 6 days after symptoms onset Fever (38.5 °C), dry cough, pneumonia None Clinical + CSF + Electrophysiology 1 Classic sensorimotor
Paterson et al. [40] UK 42 M 13 day after Distal limb numbness and weakness, dysphagia Tetraparesis, generalized areflexia, sensory loss NA Yes 16 days after symptom onset Cough, fever dyspnea, diarrhea, anosmia None Clinical + CSF + electrophysiology 1 Classic sensorimotor
Paterson et al. [40] UK 60 M 1 day before Distal limb numbness and weakness Tetraparesis, generalized areflexia, sensory loss, dysautonomia, facial and bulbar weakness Yes Yes 5 days after symptom onset Headache, ageusia, anosmia NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Paterson et al. [40] UK 38 M 21 day after Distal limb numbness, weakness, clumsiness Mild distal weakness, sensory ataxia None No NA Cough, diarrhea NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Paybast et al. [41] Iran 38 M 21 days after Acute progressive ascending paraesthesia of distal LL Quadriparesthesia, bilateral facial droop with drooling of saliva and slurred speech, generalized areflexia, swallowing inability, bilaterally absent gag reflex Tachycardia and blood pressure instability No 3 days after symptoms onset Symptoms of upper respiratory tract infection Hypertension Clinical + CSF + electrophysiology 1 Classic sensorimotor
Paybast et al. [41] Iran 14 F 21 days after Progressive ascending quadriparesthesia, mild LL weakness Mild proximal and distal LL weakness, hypoactive deep tendon reflexes in UL and absent in LL, decreased light touch, position, and vibration sensation in all distal limbs up to ankle and elbow joints, gait ataxia None No 2 days after symptoms onset Symptoms of upper respiratory tract infection None Clinical + CSF 2 Classic sensorimotor
Pfefferkorn et al. [42] Germany 51 M 14 days after UL and LL weakness, acral paraesthesia Tetraparesis, generalized areflexia, deterioration to an almost complete peripheral locked-in syndrome with tetraplegia, complete sensory loss at 4 limbs, bilateral facial and hypoglossal paresis None Yes 15 days after symptoms onset Fluctuating fever, flu-like symptoms with marked fatigue and dry cough, pneumonia NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Rana et al. [43] USA 54 M 14 days after LL paresthesias of LL Ascending tetraparesis, general areflexia, burning sensation diplopia, facial diplegia, mild ophthalmoparesis Resting tachycardia and urinary retention Yes NA Rhinorrhea, odynophagia, fever, chills, and night sweats Hypertension, hyperlipidemia, restless leg syndrome, and chronic back pain, concurrent C. Difficile infection Clinical + electrophysiology 2 Miller Fisher variant
Reyes-Bueno et al. [44] Spain 50 F 15 days after Root-type pain in all four limbs, dorsal and lumbar back pain LL Weakness, ataxia, diplopia, bilateral facial palsy, generalized areflexia Dry mouth, diarrhea and unstable blood pressure No 12 days after symptoms onset Diarrhea, odynophagia and cough NA Clinical + CSF + electrophysiology 1 Miller Fisher variant
Riva et al. [45] Italy 60+ M 17 days after Progressive limb weakness and distal paresthesia at four limbs Ascending paraparesis with involvement of the cranial nerves (facial diplegia), generalized areflexia None No 10 days after symptoms onset Fever, headache, myalgia, anosmia and ageusia NA Clinical + electrophysiology 2 Classic sensorimotor
Sancho-Saldaña et al. [46] Spain 56 F 15 days after Unsteadiness and paraesthesia in both hands Lumbar pain and ascending weakness, global areflexia, bilateral facial nerve palsy, oropharyngeal weakness and severe proximal tetraparesis No Yes 3 days after symptoms onset Fever, dry cough and dyspnea, pneumonia NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Scheidl et al. [47] Germany 54 F 11 days after Proximal weakness of LL, numbness of 4 limbs Initial worsening of the paraparesis with rapid improvement upon initiation of the treatment, areflexia None No 12 days after symptoms onset Temporary ageusia, None Clinical + CSF + electrophysiology 1 Paraparetic variant
Sedaghat et al. [48] Iran 65 M 14 days after LL distal weakness Ascending weakness, tetraparesis, facial bilateral palsy, generalized areflexia, LL distal hypoesthesia and hypopallesthesia None No 4 days after symptoms onset Fever, cough and sometimes dyspnea, pneumonia DM type 2 Clinical + electrophysiology 2 Classic sensorimotor
Sidig et al. [49] Sudan 65 M 5 days after Numbness and weakness in both UL and LL Ascending weakness, bilateral facial paraesthesia and palsy, clumsiness of UL, tetraparesis, slight palatal muscle weakness, areflexia Urinary incontinence Yes NA Low-grade fever, sore throat, dry cough, headache and generalized fatigability DM and Hypertension Clinical + electrophysiology 2 Classic sensorimotor
Su et al. [50] USA 72 M 6 days after Proximal UL and LL weakness Progression with worsening of the paresis, areflexia, hypoesthesia Hypotension alternating with hypertension and tachycardia Yes 8 days after symptoms onset Mild diarrhea, anorexia and chills without fever or respiratory symptoms Coronary artery disease, hypertension and alcohol abuse Clinical + CSF + electrophysiology 1 Classic sensorimotor
Tiet et al. [51] United Kingdom 49 M 21 days after Distal LL paraesthesia LL and UL weakness, facial diplegia, distal reduced sensation to pinprick and vibration sense, LL dysesthesia, generalized areflexia None No 4 days after symptoms onset Shortness of breath, headache and cough Sinusitis Clinical + CSF + electrophysiology 1 Classic sensorimotor
Toscano et al. [52] Italy 77 F 7 days after UL and LL paraesthesia Flaccid tetraplegia, areflexia, facial weakness, dysphagie, tongue weakness None Yes NA Fever, cough, ageusia, pneumonia Previous ischemic stroke, diverticulosis, arterial hypertension, atrial fibrillation Clinical + CSF + electrophysiology 1 Classic sensorimotor
Toscano et al. [52] Italy 23 M 10 days after Facial diplegia LL paraesthesia, generalized areflexia, sensory ataxia None No 2 days after symptoms onset Fever, pharyngitis NA Clinical + CSF + electrophysiology 1 Bilateral facial palsy with paraesthesia
Toscano et al. [52] Italy 55 M 10 days after Neck pain, Paresthesias in the 4 limbs, LL weakness Flaccid tetraparesis, areflexia, facial weakness None Yes NA Fever, cough, pneumonia NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Toscano et al. [52] Italy 76 M 5 days after Lumbar pain, LL weakness Flaccid tetraparesis, generalized areflexia, ataxia None No 4 days after symptoms onset Cough and hyposmia NA Clinical + CSF+
Electrophysiology 1 Classic sensorimotor
Toscano et al. [52] Italy 61 M 7 days after LL weakness and paraesthesia Ascending weakness, tetraplegia, facial weakness, areflexia, dysphagia None Yes NA Cough, ageusia and anosmia, pneumonia NA Clinical + CSF+ electrophysiology 1 Classic sensorimotor
Velayos Galán et al. [53] Spain 43 M 10 days after Distal weakness and numbness of the 4 limbs, gait ataxia Progression of the weakness with bilateral facial paresis and dysphagia, generalized areflexia NA No 2 days after admission Cough, pneumonia NA Clinical + electrophysiology 2 Classic sensorimotor
Virani et al. [54] USA 54 M 8 days after LL weakness, numbness Ascending weakness, tetraparesis, areflexia Urinary retention Yes Shortly after presentation in the outpatient clinic (after 2 days of symptoms onset) Fever (102 F), dry cough, pneumonia Clostridium difficile colitis 2 days before GBS onset Clinical 3 Classic sensorimotor
Webb et al. [55] United Kingdom 57 6 days after Ataxia, progressive limb weakness and foot dysaesthesia, Tetraparesis, generalized areflexia, hypoesthesia in the 4 limbs, hypopallesthesia in LL, dysphagia None Yes 3 days after symptoms onset Mild cough and headache, myalgia and malaise, slight fever, diarrhea, pneumonia Untreated hypertension and psoriasis Clinical + CSF + electrophysiology 1 Classic sensorimotor
Zhao et al. [56] China 61 F 8 days before LL weakness Ascending weakness, tetraparesis, areflexia, LL distal hypoesthesia None No 4 days after symptoms onset Fever (38·2 °C), dry cough pneumonia NA Clinical + CSF + electrophysiology 1 Classic sensorimotor
Article COVID-19 diagnosis Blood findings Auto-antibodies and screening for most common GBS causes CSF findings Electrophysiology: Neuropathy type and GBS electrophysiologic subtype MRI (brain and spinal) Management and therapy Outcome
GBS COVID-19
Agosti et al. [5] RT-PCR + chest CT Thrombocytopenia (101 × 109 /L, reference value: 125–300 × 109 /L), lymphocytopenia (0.48 × 109 /L, reference value: 1.1–3.2 × 109 /L) Negative ANA, anti-DNA, c-ANCA, p-ANCA, negative screening for Campylobacter jejuni, Mycoplasma pneumoniae, Salmonella enterica, CMV, HSV 1 and 2, VZV, influenza virus A and B, HIV, normal B12 and serum protein electrophoresis Increased total protein (98 mg/dl), cell count: 2/106 L Demyelinating
AIDP NA IVIG 400 mg/kg/day (5 days) Antiviral drugs (not specifically mentioned) Improvement, discharged home after 30 days
Alberti et al. [6] RT-PCR + chest CT NA NA Increased total protein (54 mg/dl), 9 cells/µl, negative SARS-CoV-2 PCR Demyelinating
AIDP NA IVIG 400 mg/kg (5 days) + mechanical invasive ventilation Lopinavir/ritonavir, hydroxychloroquine 24 h after admission, death because of respiratory failure
Arnaud et al. [7] RT-PCR + chest CT NA Negative anti-ganglioside and antineural antibodies, negative Campylobacter Jejuni, HIV, syphilis, CMV, EBV serology Increased total protein (1.65 g/L), no pleyocitosis, negative oligoclonal bands, negative SARS-CoV-2 PCR, negative EBV and CMV RT-PCR Demyelinating
AIDP NA IVIG 400 mg/kg (5 days) Hydroxychloroquin, cefotaxime, azithromycine Progressive improvement
Assini et al. [8] RT-PCR Lymphocytopenia, increased LDH and inflammation markers; low serum albumin (2.9 mg/dL) NA Normal total protein level, increased IgG/albumin ratio (233), negative SARS-CoV-2 PCR, presence of oligoclonal bands (both in serum and CSF) Demyelinating with sural sparing
AIDP Brain: no pathological findings IVIG 400 mg/kg (5 days) Hydroxychloroquine, arbidol, ritonavir and lopinavir + mechanical invasive ventilation 5 days after IVIG, improvement of swallowing, speech, tongue motility, eyelid ptosis and strength
Assini et al. [8] RT-PCR + chest CT Lymphocytopenia, increased LDH and GGT, leucocytosis, low serum albumin (2.6 mg/dL) Negative anti-ganglioside antibodies Normal total protein level, increased IgG/albumin ratio (170), negative SARS-CoV-2 PCR, presence of oligoclonal bands (both in serum and CSF) Motor sensory axonal, muscular neurogenic changes
AMSAN NA IVIG 400 mg/kg (5 days) Hydroxychloroquine, antiretroviral therapy, tocilizumab + tracheostomy and assisted ventilation 5 days after IVIG, improvement of vegetative symptoms, persistence of hyporeflexia and right foot drop
Bigaut et al. [9] RT-PCR + chest CT Normal blood count, negative CRP Negative anti-ganglioside antibodies, negative HIV, Lyme and syphilis serology Increased total protein (0.95 g/L), cell count: 1 × 106/L, negative SARS-CoV-2 PCR Demyelinating
AIDP Spinal: Radiculitis and plexitis on both brachial and lumbar plexus; multiple cranial neuritis (in III, VI, VII, and VIII nerves) IVIG 400 mg/kg (5 days) + non-invasive ventilation NA Progressive improvement
Bigaut et al. [9] RT-PCR + chest CT Increased CRP Negative anti-ganglioside antibodies Increased total protein (1.6 g/L), cell count: 6 × 106/L, negative SARS-CoV-2 PCR Demyelinating
AIDP NA IVIG 400 mg/kg (5 days) NA Slow progressive improvement
Bracaglia et al. [10] RT-PCR (normal chest CT) Elevated CPK (461 U/L, normal < 145), CRP 5,65 mg/dL (normal < 0.5), lymphocyto- penia (0·68 × 109/L, normal 1·10–4), mild increase of LDH (284 U/L, normal < 248), GOT and GPT (549 and 547 U/L, normal < 35), elevation of IL-6 (11 pg/mL, normal < 5.9) Negative anti-ganglioside antibodies; negative microbiologic testing on CSF and serum for HSV1-2, EBV, VZV, CMV, HIV, Mycoplasma Pneumoniae and Borrelia. Increased total protein (245 mg/dL) and increased cell count: 13 cells/mm3, polymorphonucleate 61.5% Demyelinating
AIDP NA IVIG 400 mg/kg (5 days) Hydroxychloroquine, ritonavir, darunavir Improvement of UL and LL weakness, development of facial diplegia
Camdessanche et al. [11] RT-PCR + chest CT NA Negative anti-gangliosides antibodies; negative screening for Campylobacter jejuni, Mycoplasma pneumoniae, Salmonella enterica, CMV, EBV, HSV1-2, VZV, Influenza virus A & B, HIV, and hepatitis E Increased total protein (1.66 g/L), normal cell count Demyelinating
AIDP NA IVIG 400 mg/kg (5 days) + mechanical invasive ventilation Oxygen therapy, paracetamol, low molecular weight heparin, lopinavir/ritonavir 400/100 mg twice a day for 10 days NA
Chan et al. [12] RT-PCR + chest CT Persistent thrombocytosis (maximum PC 688 ×109/L), elevated d-dimer (1.47 mg/L) NA Increased total protein (1.00 g/L), cell count: 4 × 106/L (normal), negative SARS-CoV-2 PCR Demyelinating
AIDP Brain: bilateral intracranial facial nerve enhancement IVIG 400 mg/kg (5 days) Empiric azithromycin and ceftriaxone Slight improvement of facial weakness, unchanged paraesthesia
Chan et al. [13] RT-PCR NA Negative anti-gangliosides antibodies Increased total protein (226 mg/dL), leucocytes: 3 cells/mm3, glucose: 56 mg/dL, negative SARS-CoV-2 PCR NA Lumbosacral spine: no pathological findings 5 sessions of plasmapheresis NA Resolution of dysphagia, ambulation with minimal assistance 28 days after symptoms onset
Chan et al. [13] RT-PCR NA Elevated GM2 IgG/IgM antibodies Increased total protein (67 mg/dL), leucocytes: 1 cells/mm3, glucose 58 mg/dL, negative SARS-CoV-2 PCR NA NA Mechanical invasive ventilation + 5 sessions of plasmapheresis (without benefit on ventilation) + IVIG NA Persistence of quadriparesis with intermittent autonomic dysfunction, slowly weaned from the ventilator
Coen et al. [14] RT-PCR + serology Normal (not specified) Negative anti-gangliosides antibodies; negative meningitis/encephalitis panel Albuminocytological dissociation, no intrathecal IgG synthesis, negative SARS-CoV-2 PCR Demyelinating with sural sparing
AIDP Brain: NA
Spinal: no pathological findings IVIG 400 mg/kg (5 days) NA Rapid improvement. From day 11 from hospitalisation
Rehabilitation
Ebrahimzadeh et al. [15] RT-PCR + chest CT Normal CRP (5 mg/L), normal serum protein immunoelectrophoresis Negative anti-GQ1b antibodies, negative screening for Campylobacter jejuni, HIV, EBV, CMV, influenza virus (type A and B), HCV, non-reactive VDRL Increased total protein (78 mg/dL), normal cell count (erythrocyte = 0/mm3, leukocyte = 4/mm3), normal glucose (70 mg/dL) Demyelinating
AIDP Brain: no pathological findings
Spinal: no pathological findings None Hydroxychloroquine for 5 days Improvement of muscle strength to near normal after 16 days
Ebrahimzadeh et al. [15] RT-PCR + chest CT Slightly elevated CRP (34 mg/L), normal serum protein immunoelectrophoresis Negative anti-GQ1b antibodies, negative screening for Campylobacter jejuni, HIV, EBV, CMV, influenza virus (type A and B), HCV, non-reactive VDRL NA Demyelinating
AIDP NA IVIG NA Improvement of muscle strength in all extremities after 14 days
El Otmani et al. [16] RT-PCR + chest CT Lymphocytopenia (520/ml) NA Increased total protein (1 g/L), normal cell count, negative PCR assay for
SARS-CoV-2 Motor sensory axonal
AMSAN NA IVIG 400 mg/kg/day (5 days) Hydroxychloroquine 600 mg/day; azithromycin 500 mg at the first day, then 250 mg per day At week 1 from admission no significant neurological improvement
Esteban Molina et al. [17] RT-PCR + chest X-ray Leucocyte 7400/mm3, lymphocyte 2400/mm3. Hb 14 g/dl. PC 408,000/mm3, d-Dimer 556 ng/ml. Ferritin 544 ng/ml, CRP 2.04 mg/dl, Fibrinogen 6.8 g/dl Negative bacteriological and viral tests Increased total protein (86 mg/dL), cell count: 3x106/L Demyelinating
AIDP Brain: leptomeningeal enhancement in midbrain and cervical spine IVIG 400 mg/kg/day (5 days) Hydroxychloroquine, azithromycin, ceftriaxon Motor improvement but persistence of paraesthesia
Farzi et al. [18] RT-PCR + chest CT Lymphopenia (WBC:5.9 × 109/L, neutrophils: 85%, lymphocyte:15%), elevated levels of CRP, ESR 69 mm/h NA NA Demyelinating
AIDP NA IVIG (2 g/kg over 5 days) Lopinavir/ritonavir and hydroxychloroquine Improvement after 3 days, favorable outcome
Fernández–Domínguez et al. [19] RT-PCR NA Negative anti-GD1b antibodies, negative other anti-ganglioside antibodies Increased total protein (110 mg/dL), albuminocytological dissociation Demyelinating
NA Brain: no pathological findings IVIG 20 g/day (5 days) Hydroxychloroquine, lopinavir/ritonavir NA
Finsterer et al. [20] NA NA NA NA Axonal
AMAN NA IVIG NA Recovery
Frank et al. [21] RT-PCR, + serology (IgG and IgM) WBC and CRP normal Negative hepatitis B and C, HIV and VDRL tests Two CSF analysis 2 weeks apart, both showing normal cell count and CSF biochemistry, negative SARS-CoV-2 PCR, negative PCR for HSV1, HSV2, CMV, EBV, VZV; Zika virus; Dengue virus and Chikungunya virus Axonal
AMAN Brain: no pathological findings
Spinal: no pathological findings IVIG 400 mg/kg/day (5 days) Methylprednisolone, azithromycin, albendazole Some improvement, weakness persisted
Gigli et al. [22] Chest CT + serology (negative RT-PCR) NA Negative anti-ganglioside antibodies, negative PCR for influenza A and B viruses (nasal swab) Increased total protein (192.8 mg/L), leucocytes: 2.6 cells/µL, positive Ig for SARS-CoV-2, negative SARS-CoV-2 PCR Demyelinating
AIDP NA NA NA NA
Gutiérrez-Ortiz et al. [23] RT-PCR Lymphocytes 1000 cells/UI, CRP 2.8 mg/dl Positive anti-GD1b antibodies, other anti-ganglioside antibodies negative Increased total protein (80 mg/dl), no leucocytes, glucose
62 mg/dl, negative SARS-CoV-2 PCR NA NA IVIG 400 mg/kg (5 days) NA After 2 weeks from admission complete resolution except anosmia, ageusia
Gutiérrez-Ortiz et al. [23] RT-PCR Leucopenia (3100 cells/µl) NA Increased total protein (62 mg/dl), WBC: 2/μl (all monocytes), glucose: 50 mg/dl, negative SARS-CoV-2 PCR NA NA None Paracetamol 2 weeks later complete neurological recovery with no ageusia, complete eye movements, and normal deep tendon reflexes
Helbok et al. [24] Chest CT + serology (repeated negative RT-PCR) WBC 8.1G/L (normal: 4.0–10.0G/L), CRP 2.3 mg/dL, (normal: 0.0–0.5 mg/dL), fibrinogen level 650 mg/dL (normal: 210–400 mg/dL), LDH 276 U/L (normal: 100–250 U/L), erythrocyte sedimentation rate 55 mm/1 h Negative PCR for CMV, EBV, influenza virus A/B, Respiratory Syncytial Virus and IgM antibodies for Chlamydia pneumoniae and Mycoplasma pneumoniae Increased total protein (64 mg/dl), cell count: 2 cells/mm3, serum/ CSF glucose ratio of 0.83, negative SARS-CoV-2 PCR, positive anti-SARS-CoV-2 antibodies (not determined if intrathecal synthesis or passive transfer from blood) Demyelinating with sural sparing
AIDP Spinal: no pathological findings IVIG 30 g + plasma exchange (4 cycles) + mechanical invasive ventilation None Improvement of muscle forces with recovery of mobility without significant help after 8 weeks
Hutchins et al. [25] RT-PCR + chest CT Lymphopenia (absolute lymphocyte count of 0.7 K/mm3) Serum HSV IgG and IgM. Respiratory viral panel PCR negative Negative GM1, GD1b, and GQ1b IgG and IgM), aquaporin-4 receptor (IgG), HIV 1/2, HSV 1/2 (IgG and IgM), CMV (IgM), Mycoplasma pneumoniae (IgG and IgM), Borrelia burgdorferi (IgG and IgM), Bartonella species (IgG and IgM), and syphilis (Venereal Disease Research Laboratory test) Increased total protein (49 mg/dL), normal glucose levels (65 mg/dL), no leukocytes Mixed demyelinating and axonal EMG subtype unknown Brain: enhancement of the facial and abducens nerves bilaterally, as well as the right oculomotor nerve
Spinal: no pathological findings Plasma exchange (5 cycles) NA Discharged to inpatient rehabilitation
Juliao Caamaño et al. [26] RT-PCR NA NA Normal total protein (44 mg/dL), no pleocytosis Absent blink-reflex
EMG subtype unknown Brain: no pathological findings Oral prednisolone Hydroxychloroquine and lopinavir/ritonavir for 14 days Minimal improvement of muscle weakness after 2 weeks
Khalifa et al. [27] RT-PCR + chest X-ray + chest CT WBC 5.5 × 103, PC 356 × 103, CRP 0.5 mg/dL (normal 0.0–0.5), serum ferritin 87.3 ng/ml (normal 12.0–150.0), elevated d-Dimer levels 0.72 mg/L (0.00–0.49) Negative screening for:  influenza A and B viruses; influenza A virus subtypes H1, H3, and H5 including subtype H5N1 of the Asian lineage; parainfluenza virus types 1, 2, 3, and 4; respiratory syncytial virus types A and B; adenovirus; metapneumovirus; rhinovirus; enterovirus; Coronavirus 229E, HKU1, NL63, and OC43 Cell count: 5 mm3, increased total protein (316.7 mg/dL) Demyelinating
AIDP Brain: no pathological findings
Spinal: enhancement of the cauda equina nerve roots IVIG 1 g/kg (2 days) Paracetamol, azithromycin, hydroxychloroquine Discharge to home after 15 days with clinical and electrophysiological improvement
Kilinc et al. [28] Fecal PCR + serology NA Negative anti-GQ1b antibodies, serologic tests on Borrelia burgdorferi, syphilis, Campylobacter jejuni, CMV, hepatitis E, Mycoplasma pneumoniae and CMV Normal cell count, normal proteins Predominantly demyelinating
AIDP Brain: no pathological findings IVIG 2 g/kg (5 days) None Persistence of mild symptoms at the discharge (after 14 days)
Lampe et al. [29] RT-PCR (negative chest X-ray) Slightly increased CRP (1.92 mg/dL) Negative anti-ganglioside antibodies; negative influenza and respiratory syncytial virus Increased total protein (56 mg/dL), normal cell count (2 cells/μL) Demyelinating
AIDP NA IVIG 400 mg/kg (5 days) None Improvement of GBS symptoms with persistence of generalized areflexia except for left biceps reflex, discharge after 12 days
Lantos et al. [30] RT-PCR NA GM1 antibodies in the equivocal range NA NA Brain: enlargement, prominent enhancement with gadolinium, and T2 hyperintense signal of the left cranial nerve III IVIG Hydroxychloroquine Improvement, discharge after 4 days
Lascano et al. [31] RT-PCR + chest X-ray + positive IgM (IgG positivity 2 weeks later) WBC 8900 cells/mm3; lymphocytes 1200 cells/mm3; PC 45,500 cells/mm3 Negative anti-ganglioside antibodies Increased total protein (60 mg/dL), leucocytes: 3 cells/μL, negative SARS-CoV-2 PCR Demyelinating
AIDP Spinal: no nerve root gadolinium enhancement IVIG 400 mg/kg (5 days) + mechanical
invasive ventilation Azithromycin Improvement of tetraparesis.
Able to stand up with assistance.
Lascano et al. [31] RT-PCR + chest X-ray WBC 3300 cells/mm3; lymphocytes 800 cells/mm3; PC 119,000 cells/mm3 NA Normal total protein (40 mg/dl), cell count: 2 cells/μL Mixed demyelinating (conduction blocks) and axonal with sural sparing pattern
Predominantly AIDP NA IVIG 400 mg/kg (5 days) Amoxicillin, clarithromycin Dismissal with full motor recovery. Persistence of LL areflexia and distal paraesthesia
Lascano et al. [31] RT-PCR + chest X-ray WBC 4000 cells/mm3; lymphocytes 600 cells/mm3; PC 322,000 cells/mm3 NA Increased total protein (140 mg/dL), cell count: 4 cells/μL, negative SARS-CoV-2 PCR Demyelinating with sural sparing pattern
AIDP Brain: no pathological findings
Spinal cord: lumbosacral nerve root enhancement IVIG 400 mg/kg (5 days) Amoxicillin Improvement of tetraparesis and ability to walk with assistance. Persistence of neuropathic pain and distal paraesthesia
Manganotti et al. [32] RT-PCR + chest CT NA Negative anti-ganglioside antibodies negative serum anti-HIV, anti-HBV, anti-HCV antibodies Increased total protein (74.9 mg/dL), negative CSF PCR for bacteria, fungi, Mycobacterium tuberculosis, Herpes viruses, Enteroviruses, Japanese B virus and Dengue viruses NA Brain: no pathological findings IVIG 400 mg/kg (5 days) Lopinavir/ritonavir, hydroxychloroquine, antibiotic therapy, oxygen support (35%) Resolution of all symptoms except for minor hyporeflexia at the LL
Manganotti et al. [33] RT-PCR IL-1: 0.2 pg/ml (< 0.001 pg/ml), IL-6: 113.0 pg/ml (0.8–6.4 pg/ml), IL-8: 20.0 pg/ml (6.7–16.2 pg/ml), TNF-α: 16.0 pg/ml (7.8–12.2 pg/ml) Negative anti-ganglioside antibodies, negative HIV, HBV, HCV negative serological tests for autoimmune disorders Increased total protein (52 mg/dl), leucocytes: 1 cell/mm3, negative SARS-CoV-2 PCR Demyelinating
AIDP NA IVIG 400 mg/kg/day (5 days) Hydroxychloroquine, oseltamivir, darunavir, methylprednisolone and tocilizumab + mechanical invasive ventilation Improvement of motor symptoms
Manganotti et al. [33] RT-PCR IL-1: 0.5 pg/ml (< 0.001 pg/ml), IL-6: 9.8 pg/ml (0.8–6.4 pg/ml), IL-8: 55.0 pg/ml (6.7–16.2 pg/ml), TNF- α: 16.0 pg/ml (7.8–12.2 pg/ml) Negative anti-ganglioside antibodies, negative HIV, HBV, HCV negative serological tests for autoimmune disorders Normal total protein (40 mg/dl), leucocytes: 1 cell/mm3, negative SARS-CoV-2 PCR Mixed demyelinating and axonal   EMG subtype unknown Brain: no pathological findings IVIG 400 mg/kg/day (5 days) Hydroxychloroquine, lopinavir/ritonavir, methylprednisolone + mechanical invasive ventilation Improvement of motor symptoms
Manganotti et al. [33] RT-PCR NA Negative anti-ganglioside antibodies, negative HIV, HBV, HCV negative serological tests for autoimmune disordes Increased total protein (72 mg/dL), leucocytes: 5 cell/mm3, negative SARS-CoV-2 PCR Mainly demyelinating
Predominantly AIDP Brain: no pathological findings IVIG 400 mg/kg/day (5 days) Hydroxychloroquine, lopinavir/ritonavir, methylprednisolone Improvement
Manganotti et al. [33] RT-PCR NA NA NA Mixed demyelinating and axonal  EMG subtype unknown NA Methylprednisolone 60 mg for 5 days Methylprednisolone Stationary
Manganotti et al. [33] RT-PCR IL-1: 0.2 pg/ml (< 0.001 pg/ml), IL-6: 32.7 pg/ml (0.8–6.4 pg/ml), IL-8: 17.8 pg/ml (6.7–16.2 pg/ml), TNF- α : 11.1 pg/ml (7.8–12.2 pg/ml), IL-2R: 1203.0 pg/ml (440.0–1435.0 pg/ml), IL-10: 4.6 (1.8–3.8 pg/ml) Negative anti-ganglioside antibodies, negative HIV, HBV, HCV negative serological tests for autoimmune disordes Increased total protein (53 mg/dL), leucocytes: 2 cell/mm3, negative SARS-CoV-2 PCR Mixed demyelinating and axonal  EMG subtype unknown NA IVIG 400 mg/kg/day (5 days) Hydroxychloroquine, lopinavir/ritonavir, methylprednisolone, meropenem, linezolid, clarithromycin, fluconazole, doxycycline + mechanical invasive ventilation Improvement
Marta-Enguita et al. [34] RT-PCR + chest CT Thrombocytopenia, d-Dimer elevation NA NA NA NA NA NA Death after 10 days
Mozhdehipanah et al. [35] RT-PCR (negative chest CT) Normal WBC, CRP and ESR NA Increased total protein (139 mg/dL), normal cell count, negative CSF HSV serology and gram stain and culture Demyelinating
AIDP NA Plasma exchange (5 cycles) NA Significant improvement of muscle weakness after 3 weeks, persistence of mild bifacial paresis
Mozhdehipanah et al. [35] RT-PCR Normal WBC, CRP and ESR NA Albuminocytological dissociation NA NA IVIG 400 mg/kg/day (5 days) NA Complete recovery, except for the persistence of hyporeflexia
Mozhdehipanah et al. [35] RT-PCR + chest CT Leucocytosis lymphopenia, elevated ESR and CRP NA Increased total protein (57 mg/dL), normal cell count and glucose (not further specified) Axonal
AMSAN NA IVIG 400 mg/kg/day (3 days) Hydroxy chloroquine, lopinavir/ ritonavir Death after 3 days from starting treatment with IVIG
Mozhdehipanah et al. [35] RT-PCR + chest CT Leucocytosis, lymphopenia, elevated ESR and CRP NA Increased total protein (89 mg/dL), normal cell count and glucose (not further specified) Demyelinating
AIDP NA IVIG 400 mg/kg/day (5 days) Hydroxy chloroquine, lopinavir/ ritonavir No significant clinical improvement
Naddaf et al. [36] Positive SARS-CoV-2 IgG (index value: 8.2, normal < 0.8) and IgA + chest CT (negative RT-PCR) Normal completed blood count, elevated d-dimer (690 ng/mL), ferritin (575 mcg/L), ESR (26 mm/h), alanine aminotransferase (73 U/L) Negative anti-ganglioside antibodies negative HIV, syphilis, West Nile virus, Lyme disease testing, EBV and CMV serology consistent with remote infection, negative paraneoplastic evaluation Increased total protein (273 mg/dL), total cells count: 2/mm3, negative CSF SARS-CoV-2 RT-PCR, negative meningitis/encephalitis panel, negative oligoclonal bands and IgG index Demyelinating
AIDP Spine: smooth enhancement of the cauda equine roots Plasma exchange (5 sessions) Hydroxy chloroquine, zinc, methylprednisolone 40 mg bid for 5 days Improvement of motor and gait examination. Persistence of slight ataxia without requiring gait aid
Oguz-Akarsu et al. [37] RT-PCR + chest MRT + chest CT Mild neutropenia (1.49 cells/µL) and a high monocyte percentage (19.77) HIV test negative Normal total protein (32.6 mg/dL) with no leucocytes Demyelinating with sural sparing pattern
AIDP Cervical and lumbar and spine: asymmetrical thickening and hyperintensity of post-ganglionic roots supplying the brachial and lumbar plexuses in STIR sequences Plasma exchange (five sessions, one every other day) Hydroxychloroquine, azithromycin Marked neurological improvement after 2 weeks and she was able to walk without assistance
Ottaviani et al. [38] RT-PCR + chest CT Lymphopenia, increased d-dimer, CRP and CK Negative anti-ganglioside antibodies Increased total protein (108 mg/dL), cell count: 0 cells/μL Mainly demyelinating
Predominantly AIDP NA IVIG 400 mg/kg (5 days) Lopinavir/ritonavir, hydroxychloroquine Progressive worsening with multi-organ failure
Padroni et al. [39] RT-PCR + chest CT WBC 10.41 × 109/L (neutrophils 8.15 × 109/L), normal d-dimer Negative screening for Mycoplasma pneumonia, CMV, Legionella pneumophila, Streptococcus pneumoniae, HSV, VZV, EBV, HIV-1, Borrelia burgdorferi; auto-antibodies not performed Increased total protein (48 mg/dl), cell count: 1 × 106/L Motor sensory axonal
AMSAN NA IVIG 400 mg/kg (5 days) + mechanical invasive ventilation NA At day 6 from admission: ICU with mechanical invasive ventilation
Paterson et al. [40] Definite diagnosis (not specified) (normal chest CT) Increased neutrophils and CRP NA Increased total protein (0.5 g/L),
leucocytes: 3 cells/μL (0–5), Demyelinating
AIDP NA IVIG + mechanical invasive ventilation None 17 days of hospitalisation, at discharge able to walk 5 m (across an open space) but incapable of manual work/running
Paterson et al. [40] Definite diagnosis (not specified) (normal chest CT) Increased CRP and fibrinogen NA Increased total protein (0.6 g/L)
leucocytes: 2 cells/μL (0-5), Glucose 3.4 (mmol/L; 2.2-4.2) Demyelinating
AIDP Brain: no pathological findings IVIG Mechanical invasive ventilation 46 days (ongoing) of hospitalisation, still critical and requiring ventilation
Paterson et al. [40] Definite diagnosis (not specified) (normal chest CT) Not significant findings NA Increased total protein (0.9 g/L)
leucocytes: < 1 cells/μL (0-5), Glucose 3.7 (mmol/L; 2.2-4.2) Demyelinating
AIDP Brain: no pathological findings IVIG NA 7 days (ongoing) of hospitalisation, able to walk 5 m (across an open space) but incapable of manual work/running
Paybast et al. [41] RT-PCR NA NA Increased total protein (139 mg/dL), normal glucose and cell count, normal CSF viral serology, negative gram stain and culture Mixed demyelinating and axonal  EMG subtype unknown NA 5 sessions of therapeutic plasma exchange, intravenous bolus of labetalol to control sympathetic nervous system over-reactivity Hydroxychloroquine sulphate 200 mg two times per day for a week Persistence of generalized hyporeflexia, decreased light touch sensation in distal limbs, mild bilateral facial paresis, sympathetic over-reactivity successfully controlled with labetalol,
Paybast et al. [41] RT-PCR NA NA Albuminocytological dissociation NA NA IVIG 20 g (5 days) Hydroxychloroquine sulphate 200 mg two times per day for a week Persistence of generalized hyporeflexia and decreased light touch sensation in distal limbs
Pfefferkorn et al. [42] RT-PCR + chest CT NA Negative anti-gangliosides antibodies At admission: Normal total protein, cell count: 9/µL, negative SARS-CoV-2 PCR
At day 13th: increased total protein (10.231 mg/L), normal cell count Demyelinating
AIDP Spinal: massive symmetrical contrast enhancement of the spinal nerve roots at all levels of the spine including the cauda equina. Anterior and posterior nerve roots were equally affected IVIG 30 g (5 days) + mechanical invasive ventilation + plasma exchange NA At day 31 from admission: motor improvement with regression of facial and hypoglossal paresis but still needed mechanical ventilation
Rana et al. [43] RT-PCR NA NA NA Demyelinating with sural sparing
AIDP Thoracic and lumbar spine: no evidence of myelopathy or radiculopathy IVIG 400 mg/kg (5 days) Hydroxychloroquine and azithromycin On day 4 respiratory improvement, on day 7 rehabilitation
Reyes-Bueno et al. [44] Serology (negative RT-PCR) NA Negative anti-ganglioside antibodies Increased total protein (70 mg/dl), cell count: 5 cells/µl, albuminocytological dissociation Demyelinating with alteration of the Blink-Reflex. Further EMG: polyradiculoneuropathy with proximal and brainstem involvement
AIDP NA IVIG 400 mg/kg (5 days) + Gabapentin NA After the 18th day progressive improvement of  facial and limb paresis, diplopia and pain. Consequent neurological rehabilitation
Riva et al. [45] Chest CT + serology (negative RT-PCR) No pathological findings Negative anti-ganglioside antibodies Normal total protein and cells; negative PCR for SARS-CoV2, EBV, CMV, VZV, HSV 1–2, HIV Demyelinating with sural sparing
AIDP Brain: NA
Spinal: no pathological findings IVIG 400 mg/kg (5 days) None Slowly improvement after the 10th day
Sancho-Saldaña et al. [46] RT-PCR + chest X-Ray NA Negative anti-ganglioside antibodies Increased total protein (0.86 g/L), cell count: 3 leucocytes Demyelinating
AIDP Whole spine: brainstem and cervical meningeal enhancement IVIG 400 mg/kg (5 days) Hydroxychloroquine, azithromycin Recovering by day 7 after the onset of weakness.
Scheidl et al. [47] RT-PCR No pathological findings Negative Campylobacter Jejuni and Borrelia serology, negative ANA, anti-DNA, c-ANCA,p-ANCA Increased total protein (140 g/L), albuminocytological dissociation Demyelinating
AIDP Brain: NA
Cervical spine: no pathological findings IVIG 400 mg/kg (5 days) None Complete recovery
Sedaghat et al. [48] RT-PCR + chest CT Increased WBC 14.6 × 103 (neutrophils 82.7%, lymphocytes 10.4%) and CRP NA NA Motor sensory Axonal
AMSAN Brain: no pathological findings
Spinal: two cervical intervertebral disc herniations IVIG 400 mg/kg (5 days) Hydroxychloroquine, lopinavir/ritonavir, azithromycin Not reported
Sidig et al. [49] RT-PCR + chest CT NA NA None Demyelinating
AIDP Brain: no pathological findings NA NA Death after 7 days; because of progressive respiratory failure
Su et al. [50] RT-PCR + chest X-ray WBC 12,000 cells/µl Negative anti- ganglioside GM1, GD1b and GQ1b antibodies, acetylcholine receptor binding, voltage-gated calcium channel, antinuclear and ANCA Increased total protein (313 mg/dL), WBC: 1 cell Demyelinating
AIDP NA IVIG 2gm/kg (for 4 days) None On day 28 persistence of severe weakness
Tiet et al. [51] RT-PCR Elevated lactate on venous blood gas (3.3 mmo/L), mildly elevated CRP (20 mg/L). Normal WBC, sodium, potassium and renal function. NA Increased total protein (> 1.25 g/L), cell count 1x106/L Demyelinating
AIDP NA IVIG 400 mg/kg/day (5 days) None Resolution of facial diplegia, improved upper and lower limbs weakness; able to mobilize unassisted 11 weaks after neurorehabilitation
Toscano et al. [52] RT-PCR + Chest CT + serology Lymphocytopenia, increased CRP, LDH, ketonuria Negative anti-ganglioside antibodies Day 2: normal total protein, no cells, negative SARS-CoV-2 PCR
Day 10: increased total protein (101) mg/dl, cell count: 4/mm3, negative SARS-CoV-2 PCR Axonal with sural sparing
AMSAN Brain: no pathological findings
Spinal: Enhancement of caudal nerve roots IVIG 400 mg/kg (2 cycles) + temporary mechanical non-invasive ventilation Paracetamol At week 4 persistence of severe UL weakness, dysphagia, and LL paraplegia
Toscano et al. [52] RT-PCR (negative chest CT) Lymphocytopenia; increased ferritin, CRP, LDH NA Increased total protein (123 mg/dl), no cells, negative SARS-CoV-2 PCR Motor sensory axonal with sural sparing
AMSAN Brain: enhancement of facial nerve bilaterally
Spinal: no pathological findings IVIG 400 mg/kg Amoxycillin At week 4 improvement of  ataxia and mild improvement of  facial weakness
Toscano et al. [52] RT-PCR + chest CT Lymphocytopenia; increased CRP, LDH, ketonuria Negative anti-ganglioside antibodies Increased total protein (193 mg/dl), no cells, negative SARS-CoV-2 PCR Motor axonal
AMAN Brain: no pathological findings
Spinal: enhancement of caudal nerve roots IVIG 400 mg/kg (2 cycles) + mechanical invasive ventilation Azythromicin ICU admission due to respiratory failure and tetraplegia. At week 4 still critical
Toscano et al. [52] RT-PCR + serology (negative chest CT) Lymphocytopenia; increased CRP, ketonuria NA Normal protein, no cells, negative SARS-CoV-2 PCR Demyelinating
AIDP Brain: no pathological findings
Spinal: no pathological findings IVIG 400 mg/kg None At week 4 mild improvement in UL but unable to stand
Toscano et al. [52] Chest CT + serology (negative RT-PCR in nasopharyngeal swab and BAL) Lymphocytopenia; increased CRP, LDH Negative anti-ganglioside antibodies; negative screening for Campylobacter jejuni, EBV, CMV, HSV, VZV, influenza, HIV Normal total protein (40 mg/dL), white cell count 3/mm3; negative SARS-CoV-2 PCR Demyelinating
AIDP Brain: NA
Spinal: no pathological findings IVIG 400 mg/kg + plasma exchange + mechanical invasive ventilation + enteral nutrition None At week 4 flaccid tetraplegia, dysphagia, ventilation dependent
Velayos Galán et al. [53] RT-PCR + chest X-ray NA NA NA Demyelinating
AIDP NA IVIG 400 mg/kg (5 days) Hydroxychloroquine, lopinavir/ritonavir, amoxicillin, corticosteroids + low-flow oxygen therapy NA
Virani et al. [54] rt-pcr + chest mrt WBC 8.6 × 103; Hb 15.4 g/dl; PC 211 × 103; procalcitonin: 0.15 ng/ml NA NA NA Brain: NA
Spinal: no pathological findings IVIG 400 mg/kg (5 days) + mechanical invasive ventilation (4 days) Hydroxychloroquine 400 mg bid for first 2 doses, then 200 mg bid for 8 doses At day 4 of IVIG: liberation from mechanical ventilation, resolution of UL symptoms, persistence of LL weakness. Sent to a rehabilitation facility
Webb et al. [55] RT-PCR + chest X-ray + chest CT Lymphopenia (0.9 × 109/L), thrombocytosis (490 × 109/L) raised CRP (25 mg/L) Negative ANA, ANCA, anti-ganglioside antibodies, syphilis serology HIV, hepatitis B and hepatitis C Increased total protein (0.51 g/L), normal glucose and cell count, negative SARS-CoV-2 PCR, negative viral PCR Demyelinating
AIDP NA IVIG 400 mg/kg/day (5 days) + Mechanical invasive
ventilation Co-amoxiclav After 1 week in ICU: no oxygen requirement and ventilation
Zhao et al. [56] RT-PCR + chest CT WBC 0.52 × 109; PC 113 × 109/L NA Increased total protein (124 mg/dL), cell count 5 × 106/L Demyelinating
AIDP NA IVIG (dosing not reported) Arbidol, lopinavir/ ritonavir At day 30 resolution of neurological and respiratory symptoms
AIDP, acute inflammatory demyelinating polyneuropathy; AMAN, acute motor axonal neuropathy; AMSAN, acute motor sensory axonal neuropathy; ANA, antinuclear antibodies; ANCA, anti-neutrophil cytoplasmic antibodies; BAL, bronchoalveolar lavage; CK, creatine kinase; CMV, cytomegalovirus; COPD, chronic obstructive pulmonary disease, COVID-19, coronavirus disease 2019; CRP, C-reactive protein; CSF, cerebrospinal fluid; CT, computed tomography; DM, diabetes mellitus; EBV, Epstein–Barr virus; ESR, erythrocyte sedimentation rate; F, female; GBS, Guillain–Barré syndrome; GGT, gamma-glutamyl transferase; GOT, glutamic oxaloacetic transaminase; GPT, glutamate pyruvate transaminase; Hb, haemoglobin; HIV, human immunodeficiency virus; HSV, herpex simplex virus; ICU, intensive-care unit; IL, interleukin; IVIG, intravenous immunoglobulins; IL, interleukin; LDH, lactate dehydrogenase; LL, lower limbs; M, male; MRI, magnetic resonance imaging; NA, not available; PC, platelet count; PCR, Polymerase Chain Reaction; SARS-CoV-2, severe acute respiratory syndrome coronavirus-2; TNF, tumor necrosis factor; UL, upper limbs; VDRL, Veneral Disease Research Laboratory; VZV, varicella-zoster virus; WBC, white blood cells; X-ray: radiography
aTime to Nadir refers to days elapsed between the onset of neurological symptoms and the development of the worst clinical picture when no progression was reported nadir was considered concomitant with GBS symptoms onset
bAccording to Brighton diagnostic criteria [66]
Interestingly, patients with no improvement or poor outcome (n = 19) showed a slightly higher (but not significant) frequency of clinical history and/or a radiological picture of COVID-19 pneumonia (14/19, 73.7%) compared to those with a favorable prognosis (29/48, 60.4%, p = 0.541). Moreover, the former group of patients was significantly older (mean 62.7 ± 17.8 years, p = 0.011), but with comparable distribution of sex (p = 0.622) and electrophysiological subtypes (p = 0.144) and similar latency between COVID-19 and GBS (p = 0.588) and nadir (p = 0.825), compared to the latter (mean age 51.8 ± 16.6 years). The same findings were confirmed even after excluding cases with no improvement from the analysis (to prevent a possible bias related to the short follow-up time).