Background and Aims A syndrome of persistent coagulase-negative staphylococcal (CoNS) bacteraemia has recently been recognised in neonatal intensive care unit (NICU) patients. The aim of our study was to describe the clinical profile of neonates with persistent CoNS bacteraemia and to determine the molecular patterns of isolates associated with this syndrome.

Materials and Methods The medical notes of neonates with CoNS bacteraemia, admitted in our NICU during 2006, were reviewed. Demographic (gender, gestational age, birth weight) and clinical characteristics (temperature instability, respiratory deterioration, bradycardia, feeding intolerance) as well as risk factors for sepsis (mechanical ventilation, central catheters, parenteral nutrition) were recorded. Slime production was investigated by the Christensen method, the presence of ica operon by PCR and clones were identified by pulsed-field gel electrophoresis. Persistent CoNS bacteraemia was defined as more than three consecutive positive blood cultures, at least 48 h apart.

Results A total of 15 cases of persistent and 17 of non-persistent CoNS bacteraemia were identified. The incidence of thrombocytopenia was higher in neonates with persistent compared with those with non-persistent CoNS bacteraemia (86.7% vs 29.4%; p<0.001). The incidence of predominant clones and the presence of ica operon were similar between the two groups. Logistic regression analysis revealed biofilm production as the only significant factor associated with persistent CoNS bacteraemia (p = 0.001).

Conclusions Persistent CoNS septicaemia was associated with thrombocytopenia. Clinical profile and CoNS molecular characteristics such as clonality and presence of ica operon did not differ between the persistent and non-persistent groups. However, strains producing biofilm were associated with persistent CoNS bacteraemia.