Risk factors for development of urinary tract infection in children with nephrolithiasis.

Abstract

Nephrolithiasis is one of the causes of urinary tract infection (UTI). In this study, we investigated risk factors for UTI in children with nephrolithiasis. The data from the patients with nephrolithiasis were evaluated in this retrospective follow-up study. Patients with a history of UTI before admission and congenital anomaly of kidney or urinary tract were excluded. The patients were divided into two groups: patients with UTI (recurrent UTI and single UTI) and patients without UTI. A total of 599 patients were included in this study. UTI occurred in 181 (30.2%) patients. There was a positive association between the size of stone and UTI (odds ratio (OR): 1.355, P = 0.007). Receiver operating characteristic curve analysis showed that the cut-off value of the size of stone for UTI was 5.3 mm, with a sensitivity of 74.9% and a specificity of 66.1% (area under the curve: 0.572 ± 0.028, P = 0.013). The presence of a metabolic risk factor and age at diagnosis under 2 years were significantly associated with both UTI and recurrence of UTI (OR: 2.272, P = 0.021, OR: 1.809, P = 0.028, respectively, for metabolic risk factor; OR: 1.212, P = 0.041, OR: 1.122, P = 0.046, respectively, for age at diagnosis under 2 years). Hypercalciuria was significantly associated with the recurrence of UTI (OR: 1.854, P = 0.017). The age at diagnosis, the presence of a metabolic risk factor and size of stone are significant risk factors for UTI in children with nephrolithiasis. The patients with idiopathic hypercalciuria, metabolic risk factor and age at diagnosis under 2 years have increased risk of recurrence of UTI.