Carbapenem-Resistant Acinetobacter baumannii Infection in Children From a Third-Level Hospital in Mexico: Clinical Characteristics and Molecular Epidemiology.

Background: Acinetobacter baumannii has emerged as a threat to public health due to the high prevalence of multidrug-resistant isolates. Information regarding the clinical and molecular characterization of carbapenem-resistant A. baumannii (CRAB) infections in children is scarce. Our study aimed to describe the clinical and molecular characteristics of CRAB infections in children from a third-level center in Mexico.

Methods: Consecutive cases of CRAB infections were documented during 2017-2022. Clinical and demographic data were collected from clinical records. Mass spectrometry was used for the identification of the isolates. The identification of A. baumannii strains was confirmed by conducting a polymerase chain reaction (PCR) assay targeting the gyrB sequence. In addition, the carbapenemase-encoding resistance genes were detected by PCR.

Results: Twenty-one cases of CRAB infections were documented: 76% female and 62% were neonates. The median hospital length of stay at the time of positive culture was 37 days (interquartile range, 13-54). Sixty-four percent of the isolates were recovered from bronchial secretions. A co-resistance rate greater than 60% was observed for most groups of antibiotics. All carbapenem-resistant isolates carried blaOXA-24 genes. BlaIMP genes were detected in half of the cases, with all strains co-harboring blaOXA-24 genes.

Conclusions: The present study demonstrated a high proportion of CRAB infections in the neonatal population, a high prevalence of co-resistance to antibiotics, and a high rate of isolates carrying blaOXA-24 and blaIMP genes. CRAB is a significant concern due to the mortality rate and the lack of therapeutic alternatives; implementing infection prevention and control programs is urgent to stop the spread of carbapenem-resistant A. baumannii.