Bacterial and fungal co-infection is a major barrier in COVID-19 patients: A specific management and therapeutic strategy is required

Microbial co-infections are another primary concern in patients with coronavirus disease 2019 (COVID-19), yet it is an untouched area among researchers. Preliminary data and systematic reviews only show the type of pathogens responsible for that, but its pathophysiology is still unknown. Studies show that these microbial co-infections are hospital-acquired/nosocomial infections, and patients admitted to intensive care units with invasive mechanical ventilation are highly susceptible to it. Patients with COVID-19 had elevated inflammatory cytokines and a weakened cell-mediated immune response, with lower CD4⁺ T and CD8⁺ T cell counts, indicating vulnerability to various co-infections. Despite this, there are only a few studies that recommend the management of co-infections.

Fungal Co-infections Associated with Global COVID-19 Pandemic: A Clinical and Diagnostic Perspective from China

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been sweeping across the globe. Based on a 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. Although there are few publications, COVID-19 patients, especially severely ill or immunocompromised, have a higher probability of suffering from invasive mycoses. Aspergillus and Candida infections in COVID-19 patients will require early detection by a comprehensive diagnostic intervention (histopathology, direct microscopic examination, culture, (1,3)-β-D-glucan, galactomannan, and PCR-based assays) to ensure effective treatments. 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. We provide a clinical flow diagram to assist the clinicians and laboratory experts in the management of aspergillosis, candidiasis, mucormycosis, or cryptococcosis as co-morbidities in COVID-19 patients.

Effects of fluconazole on the clinical outcome and immune response in fungal co-infected tuberculosis patients

With overuse of the broad-spectrum antibiotics, the pulmonary fungal infection increasingly becomes the most common complication associated with senile pulmonary tuberculosis (TB) and attracts intensive attentions from clinicians. Here we presented the retrospective analysis of impact of fluconazole treatment on the clinical outcome and immune response in fungal co-infected tuberculosis patients. A randomized, double-blind, placebo-controlled trial of fluconazole (100 mg per day for consecutive weeks) in fungal-positive senile tuberculosis patients was conducted in our hospital. Peripheral eosinophil counts were computed by the automatic hematology analyzer. The secretory inflammatory cytokines interferon (IFN)-γ, tumor necrosis factor (TNF)-α and chemokines chemokine C-X-C motif ligand (CXCL)9, CXCL10, CXCL11 were determined with enzyme-linked immunosorbent assay kits. The peripheral T helper 1 cells (Th1) and regulatory T cells (Treg) population were analyzed by flow cytometry. None of significant difference in respect to baseline TB score was observed between placebo and fluconazole groups. Administration of fluconazole significantly stimulated eosinophils population and secretion of inflammatory cytokines IFN-γ and TNF-α. Simultaneously, the peripheral Th1% and chemokines including CXCL9, CSCL10, CXCL11 were markedly induced in response to fluconazole treatment. Fungal infection significantly affected host immunity during tuberculosis which was effectively reversed by fluconazole treatment.