Prevalence and risk factors associated with infections linked to carbapenemase-producing Acinetobacter species circulating in the city of Yaoundé, Cameroon

Abstract

Objectives

Carbapenems are critical antibiotics used against multidrug-resistant infections, yet resistance is increasing, especially among Gram-negative bacteria like Acinetobacter species. In Cameroon, while Acinetobacter baumannii is well studied, little is known about other species such as Acinetobacter pittii, Acinetobacter nosocomialis, and Acinetobacter calcoaceticus. This study assessed the prevalence of carbapenemase-producing Acinetobacter and associated risk factors in Yaoundé hospitals.

Methods

A 6-month prospective cross-sectional study (April-September 2024) was conducted using 531 clinical samples from four health facilities. Strains were identified via morphologic, biochemical, and API 20 NE® tests. Antibiotic susceptibility was assessed using disc diffusion, and carbapenemases were characterized phenotypically.

Results

Of the samples, 4.9% yielded Acinetobacter, with A. baumannii being most common (80.8%), followed by A. calcoaceticus (11.5%) and Acinetobacter anitratus (7.7%). A. baumannii showed high antibiotic resistance, especially to beta-lactams, with 85.71% producing carbapenemases (83.33% class B and 16.67% class A). Significant risk factors included hospitalization, current antibiotic therapy, recent antibiotic use, and age group 38-47 years.

Conclusions

These findings highlight an urgent need for better surveillance, stricter antibiotic stewardship, and enhanced infection control strategies to limit the spread of resistant Acinetobacter infections in Yaoundé’s health care settings.