Kids’ recurrent stone risk may rise with family history

History taking in a child who presents with a first episode of nephrolithiasis should include determination of whether there are affected family members, because pediatric patients with a positive family history appear to be at risk for recurrent stones, according to research reported at the AUA annual meeting in Orlando, FL.

Editor's note: This article has been updated since its original publication to include additional study data and commentary from the author/presenter.

Orlando, FL-History taking in a child who presents with a first episode of nephrolithiasis should include determination of whether there are affected family members, because pediatric patients with a positive family history appear to be at risk for recurrent stones, according to research reported at the AUA annual meeting in Orlando, FL.

Necole M. Streeper, MD, and colleagues evaluated the characteristics of patients seen in their pediatric stone clinic at the University of Wisconsin, Madison between 2007 and 2013. Patients were selected for the retrospective study if they had calcium-based nephrolithiasis and a positive, parent-reported family history of stone disease.

A total of 30 sequentially identified patients met the inclusion criteria. Mean number of stone episodes per child was 1.3, the average number of surgical interventions per child was 0.67, and one-third of the children were being treated with medication to prevent stone recurrence.

Review of the clinical features of the patients in the study and findings from 24-hour urine evaluation (27 patients) revealed a non-genetic etiology for stone disease in three patients (renal tubular acidosis in one patient and treatment with topiramate [Topamax] in two), while almost two-thirds of the cohort had more than one metabolic risk factor for nephrolithiasis.

High prevalence of treatment in cohort

“The high prevalence of pharmacologic treatment for stone prevention in this cohort was noteworthy as was the proportion of patients with more than one risk factor, highlighting the importance of obtaining a 24-hour urine in these patients,” said Dr. Streeper, endourology fellow at the University of Wisconsin, who worked on the study with Stephen Y. Nakada, MD, and Kristina Penniston, PhD.

“Based on these features, we believe that children with a positive family history of stone disease might particularly benefit from referral to a stone clinic that provides multidisciplinary care in order to establish a comprehensive and targeted management plan aimed at preventing future episodes,” Dr. Streeper added.

The patients included in the study had an average age of about 12 years, and the majority were female (60%). The children were normal weight on average based on mean body mass index (21.5 kg/m²); only five (16.7%) were obese.

Continue to the next page for more.

Low volume, hypocitraturia among risk factors

The most common risk factors identified in the urine analyses were low volume (59.3%), hypocitraturia (44.4%), and hypercalciuria (37.0%). Other abnormalities found were hyperoxaluria (14.8%), hypernatriuria (11.1%), and hyperuricosuria (7.4%).

Information on family history showed the prevalence rates for first-degree and second-degree family history were identical (53.3%). Among children with a first-degree family history, it was more common for a father to be affected than a mother (15% vs. 9%).

“The fact that the positive family history in these patients involved second-degree relatives as often as first-degree relatives suggests there is a genetic component in addition to environmental factors contributing to their risk for stone disease,” Dr. Streeper said.UT