Characteristics of infant urolithiasis: A single center experience in western Turkey

Urolithiasis (UL) in infancy has different incidence, etiology, presentation and course compared to UL in childhood and in adults. We evaluated the clinical, radiological, metabolic factors and course of infant UL in western Turkey.

Medical records of the infants between 1 and 12 months of age with a diagnosis of UL were reviewed retrospectively for gender, gestational age, age at diagnosis, presenting symptoms, past medical history, parental consanguinity, family history of UL, urinary tract abnormalities, urinary tract infections, localization-size-number of stones, course of stones, treatment modality of UL (medical vs surgical) and follow up duration. Patients were grouped as those who did not require surgical intervention (Group 1) and those who underwent any kind of stone surgery (Group 2). Both groups were compared for the study parameters.

There were 80 infants (48 males) with a mean age of 6.0 ± 2.9 months at diagnosis. Mean follow-up duration was 29.7 ± 23.1 months. Two thirds of the patients presented with symptoms/signs not directly related to urinary system. Predisposing factors included metabolic abnormalities in 24 (30%) patients and urinary tract malformations in 9 (11%) patients. Group 1 (n = 58) and Group 2 (n = 22) were not different with respect to the study parameters except for the larger stone size and higher rate of hyperuricosuria in Group 2. Stone size of 4.5 mm has a 72.7% sensitivity and 74.1% specificity for predicting surgical intervention. Infants treated medically and those followed by hydration only did not differ for regression rate of stones and for requirement for surgical intervention. However, metabolic abnormalities were significantly higher in medically treated infants.

Every infant with urolithiasis should be evaluated for risk factors. Modification of such predisposing factors when possible may mitigate the notably high recurrence rate of UL in children. Increased awareness of infant UL may allow for earlier detection, improved evaluation and follow up, and may thereby decrease the morbidity of the disease.