To assess cellulitis in the neonatal intensive care unit (NICU) setting and identify risk factors for its disease severity and whether cellulitis influences length of stay (LOS).

In this retrospective study, patients with cellulitis were identified using the electronic health record while admitted to the NICU at Massachusetts General for Children from January 2007 to December 2020. Demographic and clinical data were extracted from patient records. Two multivariable logistic regression models were constructed to assess for independent predictors for increased LOS (≥30 days) and complicated cellulitis in the hospital.

Eighty-four patients met the study criteria; 46.4% were older than 14 days at the time of diagnosis of cellulitis, 61.9% were non-White, and 83.3% were born prematurely; 48.8% had complicated cellulitis as defined by overlying hardware (41.7%), sepsis (7.1%), requirement for broadened antibiotic coverage (7.1%), bacteremia (4.8%), and/or abscess (3.6%). The mean hospital LOS was 58.5 ± 36.1 days SD, with 72.6% having a LOS greater than 30 days. Independent predictors of increased LOS were extreme prematurity (<28 weeks’ gestation) (OR: 14.7, P = .03), non-White race (OR: 5.7, P = .03), and complicated cellulitis (OR: 6.4, P = .03). No significant predictors of complicated cellulitis were identified.

This study identifies complicated cellulitis in the NICU as an independent predictor of increased hospital LOS in neonates. Implementation of strategies to mitigate the development of cellulitis may decrease LOS among this high-risk population.