ABSTRACT
Aim and background: The COVID-19 pandemic has raised significant concerns over secondary infections because of the widespread use of steroids, immunomodulators, and empiric antimicrobials as part of the recommended treatment protocol. Various studies have shown that COVID-19 infection by itself predisposes to secondary infections. During the 2nd wave of the COVID-19 pandemic, there has been an unprecedented epidemic of secondary invasive fungal infections. This study analyses the prevalence, details, and outcomes of secondary infections in critical COVID-19 patients admitted to a tertiary intensive care unit (ICU) in India. Materials and methods: Retrospective study of secondary infections in ICU patients between April and June 2021. Demographic data, details of immunomodulator therapy, secondary bacterial and fungal infections, antimicrobial susceptibility data, and clinical outcomes of these patients were analyzed. Results: 71/238 (29.83%) ICU patients developed secondary bacterial and fungal infections. The mortality in patients with secondary infections was significantly higher [80.28% (p < 0.05)], compared to overall ICU mortality of 51.68%. In patients with secondary infections, 67.6% were referred from other hospitals after receiving initial treatment and 64.79% had received various immunomodulator therapies. Patients on prolonged mechanical ventilation (>7 days) and indwelling central venous (>7 days) and urinary catheters (>7.5 days) had higher secondary infection rates and higher mortality. There was positive significant growth in 80 respiratory samples, 34 blood samples, and 17 urine samples. Gram-negative bacteria were isolated in 85.91% and 32.39% had fungal isolates. Klebsiella pneumoniae followed by Acinetobacter baumannii were the predominant bacteria and Candida spp followed by Mucormycosis were the predominant fungal pathogens. Multi-drug resistant (MDR) infections were common among the isolates (70.59%). 49.3% of secondary infection patients had polymicrobial infections including fungal infections with higher mortality of 83%. Conclusion: There is a significantly high incidence of secondary MDR bacterial and fungal infection including Mucormycosis in critically ill COVID-19 patients, with an adverse impact on mortality. Risk factors included the use of steroids, immunomodulators, severe COVID-19 infection, empiric broad-spectrum antibiotics, invasive ventilation, and central venous and urinary catheterization, and prolonged ICU stay.