Broad spectrum antibiotics in newborns increase multi-drug resistant infections.

Our objective was to determine if broad spectrum antibiotics (BSA) are associated with multi-resistant bacterial (MRB) infections in neonatal patients. We conducted a case-control study with two groups of patients: those with and without a MRB infection. We included 43 cases and 43 controls. MRB strains were: 21 S. maltophila (49%), 11 ESBL-producing Enterobacteriae (25%), 8 P. aeruginosa (19%) and 3 MRSA (7%). Odds ratio (OR) for MRB after seven days of carbapenems was 4.25 (95% confidence interval (CI) 1.4-17.4) and OR for MRB after seven days of third generation cephalosporin was 8 (95% CI 1.1-34.9). BSA longer than seven days, increases MRB infections 22.5 times in patients with bronchopulmonary dysplasia (BPD). Our data show a clear association between the use of BSA and the development of MRB infections, especially in BPD. Although we cannot state this is a causal relationship, we can recommend avoiding prolonged treatment with these antibiotics in preterm babies at risk of BPD.