Pleural Infections: Antimicrobial Susceptibility Patterns of Bacterial Isolates and Associated Factors in Suspected Hospitalized Patients at Arba Minch General Hospital, Southern Ethiopia

Pleural infection remains a clinical problem with high morbidity and mortality all over the world. Antimicrobial options are uncertain due to the lack of understanding of the bacteriology of pleural infection. Thus, the goal of this study was to determine bacteriological profiles, antimicrobial susceptibility patterns, and factors associated with pleural infection.

An institution-based cross-sectional study was undertaken in Arba Minch General Hospital from 1^st January to 30^th November 2020. Socio-demographic, clinical, and behavioral data were collected using a pre-tested, structured questionnaire. Adducted amounts of pleural fluid samples were collected aseptically with sterile test tubes. Standard procedures were utilized for bacterial identification, and antimicrobial susceptibility testing was done using Kirby–Disk Bauer's diffusion method. Version 25 of the Statistical Package for the Social Sciences (SPSS) was used to analyze the data. The p-value of 0.05 was considered statistically significant.

A total of 152 hospitalized patients were enrolled in this study. The overall magnitude of bacterial pleural infection was 27.6%. The predominant bacteria isolated were Staphylococcus aureus with 34.9%, followed by Escherichia coli with 11.6%. Multidrug-resistant (MDR) isolates account for around 48.8% of all isolates, with Gram-positive bacterial isolates accounting for 71.4%. Methicillin-resistant was found in 26.7% and 33.3% of isolated Staphylococcus aureus (MRSA) and coagulase-negative staphylococci (CoNS), respectively. One isolate of Enterococcus spp. was found to be vancomycin-resistant. All isolated Streptococcus pneumoniae and Streptococcus pyogenes were susceptible to penicillin, erythromycin, cotrimoxazole, and vancomycin. Likewise, isolated Pseudomonas aeruginosa was susceptible to piperacillin. The pleural infection showed a statistically significant association with age group less than or equal to 25 years old (p<0.001), hospital admission for more than seven days (p<0.007), chest tube drainage (p<0.021), previous history of pneumonia (p<0.029) and habit of alcohol drinking (p<0.029).

The overall rate of culture-confirmed pleural infection was high, and a considerable percentage of bacteria isolates showed increased resistant to routinely used antibiotics, indicating that more attention is needed to follow the spread and emergence of drug-resistant bacterial agents.