Risk factors for bacterial infections in patients with moderate to severe COVID-19: A case control study

Abstract

ObjectiveBacterial infections are known to complicate respiratory viral infections and are associated with adverse outcomes in COVID-19 patients. A case control study was conducted to determine risk factors for bacterial infections where cases were defined as moderate to severe/critical COVID-19 patients with bacterial infection and those without were included as controls. Logistic regression analysis was performed.ResultsOut of a total of 50 cases and 50 controls, greater proportion of cases had severe or critical disease at presentation as compared to control i.e 80% vs 30% (p<0.001). Hospital acquired pneumonia (72%) and Gram negative organisms (82%) were predominant. Overall antibiotic utilization was 82% and was 64% in patients who had no evidence of bacterial infection. The median length of stay was significantly longer among cases compared to controls (12.5 versus 7.5 days) (p=0.001). The overall mortality was 30%, with comparatively higher proportion of deaths among cases (42% versus 18%) (p=0.009). Severe or critical COVID-19 at presentation (AOR: 4.42 times; 95% CI; 1.63-11.9) and use of steroids (AOR: 4.60; 95% CI 1.24-17.05) were independently associated with risk of bacterial infections. These findings have implications for antibiotic stewardship as antibiotics can be reserved for those at higher risk for bacterial superinfections.

Coronavirus disease 2019 (COVID-19): Secondary bacterial infections and the impact on antimicrobial resistance during the COVID-19 pandemic

“…In several studies, mortality rates were significantly higher in COVID-19 patients with bacterial coinfections or secondary bacterial infections compared with those without. 12,14,15,19,24,35,[37][38][39] Notably, in one study, high 14-day mortality rates (54.8%) and 30-day mortality rates (66.7%) were reported among 42 hospitalized patients with COVID-19 and S. aureus bacteremia. 25 In a second study of 1,705 patients with COVID-19, mortality rates were significantly higher in patients with CA bacterial infections compared to those without (47.5% vs 18.0%; P < .001).…”

“…14,23 Specifically, in a case-control study of 50 COVID-19 patients with bacterial infections, 56% had HA bacterial pneumonia versus 16% with CA pneumonia. 24 The higher rates of HA infections may be linked to ICU admission, ventilator-associated infections, and prolonged hospital stay. 16 Indeed, a single-center study of hospitalized patients with COVID-19 in the United States reported that ICU stay and mechanical ventilation were independent predictors of HA infection in patients hospitalized with COVID-19.…”

“…21 In several studies the rates of HA and/or ventilator-associated pneumonia (VAP) infection were >50% (Table 3). 12,[24][25][26] Although we specifically looked at bacterial infections, a few studies reported rates both for bacterial and fungal infections together. 21,[27][28][29][30] Rates reported in hospitalized patients with COVID-19 varied from 3.6% up to 42.2% (Tables 2-3).…”

“…1). 22,24,26,27,[32][33][34] Notably, only 2 additional microorganisms were observed to only cause CA infection: Enterobacter cloacae (2 cases among 5 patients with bacterial respiratory infections) 18 and Proteus mirabilis (18 (8%) of 221 cultures from 183 patients with COVID-19 and CA infections). 21 Each was reported in 1 study.…”

“…Along with increased mortality, other noteworthy trends among COVID-19 patients with bacterial coinfection or secondary bacterial infection included prolonged length of hospital stay, 14,15,21,24,40 more frequent ICU admission, 13,15,19,21,24,40 and use of invasive mechanical ventilation. 21,24,28,38,40,[42][43][44][45] In a study of 100 COVID-19 patients, patients severely or critically ill at the time of admission were 4.4 times more likely to develop a bacterial infection, 24 and those with bacterial infections were more likely to be admitted to the ICU compared with patients without bacterial infections (56% vs 18%; P < .001). 24 Similarly, patients with CA bacterial pneumonia (CABP) were more likely to be admitted to the ICU compared with patients without coinfections (33% vs 16%; P < .01).…”