Urinary tract infection (UTI) in childhood is a common problem, which is frequently dismissed as trivial because most children with UTI have a good outcome. However, UTI is an important cause of acute illness in children and causes a considerable burden of ill health on children and families. In addition, UTI may be a marker of an underlying urinary tract abnormality. UTI in a few may cause significant long-term morbidity, renal scarring, hypertension, and renal impairment that may not present until adult life. Predicting which children will go on to have long-term sequelae remains a challenge.The risk of renal scarring is greatest in infants, the very group in whom diagnosis is often overlooked or delayed because clinical features are non-specific. Delay in treatment is associated with an increased risk of scarring in susceptible children. Thus accurate and rapid diagnosis of UTI is essential and requires a very high index of suspicion particularly in the youngest.The role of vesicoureteric reflux in acquired scarring is not fully understood though there is clearly an association, possibly because it is a risk factor for acute pyelonephritis. Scarring when it occurs is in the areas affected by acute pyelonephritis. Higher grades of reflux are associated with a worse outcome.Management and investigation of children with UTI consumes considerable healthcare resources. Limited understanding of the natural history and basic pathophysiology, variations in strategy with time and setting, and lack of evidence on long-term outcomes have resulted in considerable uncertainty. Some propose a minimal approach doing little investigation unless there is clear evidence for it; others favour an approach of continuation of current practice based on clinical experience until further evidence evolves. Some of the themes behind these controversies are explored.
The presence of vesicoureteric reflux does not identify a population at risk for renal scarring following a first urinary tract infection
