Quantitative and Qualitative Determination of Biofilm Formation Pattern in Multidrug Resistance Acinetobacter baumannii in Correlation with COVID-19 and Respiratory Infected Patients

Abstract

Respiratory tract infection (RTI) is one of the triggering factors that cause severe and life-threatening health problems. Acinetobacter baumannii frequently causes nosocomial infections, especially in intensive care units (ICUs). Multidrug-resistant (MDR) A. baumannii encodes multiple virulence factors that contribute to chronic diseases, as well as antibiotic resistance; among them is the capacity to colonize and produce Biofilm on biotic and abiotic surfaces that is the primary source of worry in hospital environments. The study assessed the role of antibiotic resistance and biofilm formation patterns caused by MDR A. baumannii between isolates from COVID-19 and respiratory-infected patients in Baghdad Medical City hospitals and Teaching laboratories. This study included isolating and identifying A. baumannii from the sputum samples of respiratory tract-infected patients. (some of them infected with COVID-19) . Diagnosis of isolates was done by conventional cultural, microscopical and biochemical methods and confirmed by API 20E and VITEK2 system. Investigation of the susceptibility profile of the isolates against 18 types of antibiotics was tested, and the determination of A. baumannii biofilm formation was recorded by qualitative and quantitative methods. Results showed that 36 bacterial isolates were identified as A. baumannii. Most isolates were resistant to antibiotics, including all penicillins and cephalosporins (including inhibitor combinations), fluoroquinolones and aminoglycosides, followed by carbapenems antibiotics. In contrast, all isolates were susceptible to colistin (94.4%), followed by minocycline (36.1%), and the proportions of MDR, XDR, and PDR were 19.4%, 77.8 %, and 2.8 %, respectively. All isolates of A. baumannii showed biofilm formation (100%) by Quantitative method(MTP) and 91.6%. By the qualitative approach, we can conclude that there were no significant changes in biofilm values after 48 hours between groups with and without COVID-19 infection. However, there was a significant difference in adherence levels of bacteria between COVID-19 groups, with a higher proportion of solid adherence in the COVID-19 group compared to moderate adherence in the COVID-19-free group patients. Keywords: Acinetobacter baumannii, Antibiotic Susceptibility, Biofilm formation patterns, COVID-19 and respiratory infected patients.