Randomized Placebo-Controlled Trial of Topical Mupirocin to Reduce Staphylococcus aureus Colonization in Infants in the Neonatal Intensive Care Unit

To evaluate the efficacy of topical mupirocin in reducing Staphylococcus aureus colonization in infants in the neonatal intensive care unit (NICU).A prospective double-blind randomized controlled trial of mupirocin vs placebo in S aureus-colonized infants was conducted in a tertiary care NICU between October 2016 and December 2019. Weekly universal active surveillance with polymerase chain reaction screening identified colonized infants. Colonized infants received a 5-day course of mupirocin (mupirocin group) or petroleum jelly (control group). Repeat courses were given for additional positive screens.A total of 216 infants were enrolled; 205 were included in data analyses. Primary decolonization was more successful for mupirocin-treated infants (86 of 104 [83%]) than for controls (20 of 101; 20%) (P .001). Although recurrent S aureus colonization occurred frequently (59 of 81 [73%] mupirocin-treated and 26 of 33 [79%] controls), subsequent decolonization remained more successful for mupirocin-treated infants than for controls (38 of 49 [78%] vs 2 of 21 [10%]; P .001). Subgroup analyses of infants of ≤30 weeks' gestational age yielded similar results; decolonization occurred more often in mupirocin-treated infants compared with control infants (63 of 76 [83%] vs 13 of 74 [18%]; P .001). Bacterial sterile site infections tended to be less frequent in mupirocin-treated infants compared with controls (2 of 104 [2%] vs 8 of 101 [8%]; P = .057). No invasive S aureus infections occurred in mupirocin-treated infants, but 50% of infections in controls were from S aureus, and 1 resulted in death.Universal active surveillance and targeted treatment with topical mupirocin is a successful decolonization strategy for NICU infants and may prevent S aureus infection. However, S aureus colonization frequently recurs, necessitating repeat treatment.Clinicaltrials.gov: NCT02967432.