Fungal and bacterial co-infections of the respiratory tract among patients with COVID-19 hospitalized in intensive care units.

Backgrounds: The pandemic of COVID-19 has created a global public health crisis. ICU patients with COVID-19 are prone to infections of bacterial and/or fungal origins due to several risk factors. Consequently, the current study was conducted to evaluate the frequency, demographic characteristics, underlying conditions, and etiologic agents of fungal and bacterial co-infections of the respiratory tract among ICU patients with COVID-19 in Iran. Materials and methods: From May to October 2020, sputa and endotracheal aspirates were collected from ICU patients hospitalized with COVID-19 who also were suspected of bacterial and/or fungal co-infections according to inclusion criteria. The etiologic agents of bacterial co-infections were identified using the Vitek 2 identification method. For fungal identification, all samples were analyzed by direct microscopy using KOH 10% and culture. Furthermore, all isolates were subjected to sequencing method. Results: A total of 73 lung specimens were obtained from patients who met the inclusion criteria. Of these, in 15 cases (20.54%) fungal and/or bacterial co-infections were confirmed. Males were more infected (73.33%) and all of them were between 49 and 79 years. Candida albicans (n = 8, 61.53%) and Klebsiella pneumoniae (n = 5, 38.46%) were the most frequent etiologic agents related to fungal and bacterial co-infections, respectively. Pneumonia (n = 15, 100%) and diabetes mellitus (n = 8, 53.33%) were documented as the most prevalent underlying conditions. In the current study, 3 out of 15 patients (20%) died. Conclusion: The frequency of bacterial co-infections of the respiratory tract in ICU patients hospitalized with COVID-19 was relatively high. According to the results, one of the causes of death of these patients could be a secondary infection.

Phylogenetic Analysis of Clinically Relevant Fusarium Species in Iran.

Fungi of the genus Fusarium are well known as major plant pathogens but also cause a broad spectrum of human infections. Sixty-three clinical isolates, collected during 2014-2017, were identified using a part of the TEF1 gene as barcoding marker. Fusarium fujikuroi species complex (FFSC, n = 41, 65%) showed to be the dominant etiological agent, followed by F. solani species complex (FSSC, n = 14, 22%) and F. oxysporum species complex (FOSC, n = 7, 11%). There was one strain belonging to F. lateritium species complex (FLSC, n = 1, 1.5%). For final identification, a phylogenetic tree was constructed including the type strains of each species complex. Most cases of fusariosis were due to nail infection (n = 38, 60.3%), followed by keratitis (n = 22, 34%). Fusarium infections are difficult to be treated due to their intrinsic resistance to different azoles; however, accurate and fast identification of etiological agents may enhance management of the infection. We present the first phylogenetic study on clinical Fusarium spp. from Iran.