A retrospective study (2001-2017) of acute and chronic morbidity and mortality associated with Staphylococcus aureus bacteraemia in a tertiary neonatal intensive care unit

Abstract

Background: Staphylococcus aureus bacteraemia (SAB) in NICU patients can cause significant morbidity and mortality.

Aims: To review early and late neonatal SAB with regard to risk factors, treatment, acute complications and long-term outcomes.

Methods: A retrospective study of laboratory confirmed SAB over a 16-year period (November 2001-January 2017) in a tertiary neonatal unit in Ireland.

Findings: A total of 74 neonates (MSSA n = 72, MRSA n = 2) were identified; 8.1% (n = 6) early sepsis, 91.8% (n = 68) late sepsis. Low birth weight neonates (born weighing less than 2500 g) 80% (n = 59). Median age to bacteraemia 11 days post-delivery (range = 0-100 days); median onset early sepsis 1.5 days versus late sepsis 12 days. Complications of SAB; cellulitis n = 17, pneumonia n = 12, necrotising enterocolitis n = 7, thromobophlebitis n = 5, skin abscess formation n = 4, osteomyelitis n = 3, endocarditis n = 1. Late SAB mortality 6.4% (n = 3).

Conclusions: Preterm and low birth weight infants were at highest risk of SAB. Only a small proportion of affected children had long-term clinical sequelae on follow-up. The high rate of recurrence and breakthrough bacteraemia suggests that early implementation of a targeted anti-staphylococcal antimicrobial regimen may be of particular benefit.

Keywords: Neonatal intensive care unit; Outcomes; Staphylococcus aureus bloodstream infection.