Superadded Bacterial Infections in COVID–19 Patients, Antimicrobial Susceptibility and Association with Serological Markers

ABSTRACT

Objective: To determine the frequency and antimicrobial susceptibility pattern of pathogens responsible for superadded bacterial infection in COVID-19 patients and correlate the association of these infections with serological markers. Study Design: Cross-sectional study. Place and Duration of study Department of Pathology, Combined Military Hospital, Multan Pakistan, from Jan to Dec 2021. Methodology: A total of 290 patients having positive RT-PCR for SARS CoV-2 were included. All samples were processed per Clinical Laboratory Standard Institute (CLSI) protocols. API 20E and API 20NE were used for the identification of Gram-negative rods. Antimicrobial susceptibility testing was performed by the modified Kirby Bauer disc diffusion method. Serological markers, including C-reactive protein (CRP), total leucocyte count (TLC) and serum Ferritin, were determined and compared for significance in positive and negative culture cases. Results: A total of 75 patients had positive bacterial cultures. Among these, 42(56%) were blood culture, 26(35 %) were respiratory culture and 7(9%) were urine culture. Commonly isolated organisms were Acinetobacter baumannii, Klebsiella pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa, i.e., 23(31%), 20(27%), 13(17%), and 12(16%) respectively. CRP, TLC and S. ferritin were markedly raised in superadded bacterial infection compared to patients with COVID-19 infection only. Conclusion: The frequency of superadded bacterial infections in COVID-19 patients is high. The pathogens isolated in these cases were multidrug-resistant, reflecting mostly hospital-acquired flora. The association of serological markers in depicting superadded infection is statistically significant and may be used to screen for superadded bacterial infection in COVID-19 patients. © 2023, Army Medical College. All rights reserved.