Infezioni delle vie urinarie: dalla diagnosi alla terapia

Urinary tract infections (UTIs) are a common occurrence in the paediatric population and are often paucisymptomatic in children under two years of age. A definitive diagnosis is obtained through urine culture, which should be collected using invasive methods or midstream urine. Intravenous (IV) therapy is indicated for infants under two months of age, in cases of complicated UTIs, or when there is a suspicion of poor therapeutic adherence. The effectiveness of oral antibiotic therapy (OS) has not shown to be inferior to that of IV therapy in other cases. Two large studies have shown that the effectiveness of a 5-day antibiotic therapy is not inferior to a 10-day one. The addition of corticosteroids, although it is safe, does not show solid evidence regarding its benefit and remains at the clinician's discretion. After a first episode of UTI, a renal ultrasound should always be performed to rule out underlying conditions such as vesicoureteral reflux or renal hypodysplasia. Other diagnostic investigations, such as voiding cystourethrography and renal scintigraphy with MAG3 or DMSA, should be performed only as a second step if specific abnormalities are detected on ultrasound or if there are specific clinical findings. UTIs rarely result in renal scarring, which is more often associated with congenital conditions. Moreover, unilateral renal scars are very rarely correlated with a decline in renal function. The usefulness of antibiotic prophylaxis in VUR (vesicoureteral reflux) has been questioned by numerous studies, which have demonstrated its limited effectiveness in reducing the recurrence of UTIs and its ineffectiveness in preventing renal scars, both in children with low-grade and high-grade VUR.