By analyzing retrospective analysis of SARS and influenza data from China and worldwide, we surmise that the fungal co-infections associated with global COVID-19 might be missed or misdiagnosed. Further, as a life-threatening infectious disease, COVID-19 patients showed overexpression of inflammatory cytokines, and impaired cell-mediated immune response with decreased CD4 + T and CD8 + T cell counts, indicating its susceptibility to fungal co-infection. Moreover, COVID-19 patients accompanied with immunocompromised state, such as prolonged neutropenia, HSCT, GC use, SOT, inherited or acquired immunodeficiencies, and tumor are more likely to develop fungal co-infection. Here, we summarized updated diagnostic information (histopathology, direct microscopic examination, culture, (1,3)-β-d-glucan, galactomannan, PCR-based assays, MALDI-TOF technology, etc.) and treatment recommendations of invasive mycosis. We suggest it is prudent to assess the risk factors, the types of invasive mycosis, the strengths and limitations of diagnostic methods, clinical settings, and the need for standard or individualized treatment in COVID-19 patients. Finally, provide a clinical flow diagram (Fig. 1) to assist the clinicians and laboratory experts in the management of aspergillosis, candidiasis, mucormycosis, or cryptococcosis as comorbidities in COVID-19 patients.
Fig. 1 Diagnostic and therapeutic pathway for invasive fungal co-infection