The identification of risk factors and outcomes of cerebrospinal fluid shunt infections caused by carbapenem-resistant gram-negative bacteria in children: a retrospective cohort

OBJECTIVE Cerebrospinal fluid (CSF) shunt infections caused by gram-negative bacteria are difficult to treat given the limited treatment options and the emergence of carbapenem-resistant (CR) strains. This study aimed to evaluate the demographic and clinical characteristics of children with CSF shunt and external ventricular drain (EVD) infections caused by gram-negative bacteria, to identify the risk factors for acquiring CR CSF shunt infections, and to report on the clinical outcomes of these infections. METHODS A retrospective cohort study was designed to evaluate pediatric patients with CSF shunt and EVD infections caused by gram-negative bacteria between January 2013 and February 2023. RESULTS A total of 64 episodes in 50 patients were evaluated. There were 45 (70.3%) CSF shunt infections and 19 (29.7%) EVD infections. The median (range) ages were 1.4 years (9 months-17.5 years) for CSF shunt infection patients and 4.2 years (1 month-17 years) for EVD infection patients. The most common isolated gram-negative bacteria species in CSF shunt infections were Pseudomonas spp. (12, 26.7%), followed by Escherichia coli (11, 24.4%), Klebsiella pneumoniae (9, 20%), and Enterobacter cloacae (5, 11.1%). In EVD infections, the most common isolated gram-negative bacteria species were Acinetobacter spp. (6, 31.6%), followed by Pseudomonas spp. (4, 21.1%) and E. coli (3, 15.8%). The carbapenem resistance rate was 26.3% (n = 5) in EVD infections and 26.2% (n = 11) in CSF shunt infections. When risk factors for carbapenem resistance were evaluated for CSF shunt infections, prior carbapenem treatment and a prolonged hospital stay > 7 days were risk factors for the CR group (p = 0.032 and p = 0.042, respectively). In definitive treatment, colistin was statistically more commonly used in the CR group (p = 0.049). When outcomes were evaluated, the 30-day mortality rate (18.2% vs 0%) was higher in the CR group, without a significant difference (p = 0.064). CONCLUSIONS A prolonged hospital stay > 7 days and prior carbapenem exposure within 30 days were associated with CR shunt infections caused by gram-negative bacteria.