Thrombocytosis as a predictor of serious bacterial infection

Abstract

Fever is one of the most common conditions requiring the attention of the pediatrician. The evaluation of an infant with febrile illness and no obvious focus of infection is a challenging task and can be expensive, timeconsuming and invasive. The general condition of the infant can be deceptive and does not assist reliably in clinical differentiation of a low risk versus high risk bacterial infection(1). This is compounded by the fact that no single laboratory test has been shown to identify infants with serious bacterial infection (SBI). Laboratory markers which have been used to predict SBI include raised white blood cell (WBC) counts, C-reactive protein (CRP), procalcitonin (PCT) and even interleukin-6 levels(2). WBC count, though easily available and used widely as a predictor of SBI, by itself, does not compare well with relatively more recent markers like CRP and PCT.