Abstracts

Rationale: It is known that urinary stones may occur in epilepsy patients treated with topiramate (TPM). Urinary stones also found in a proportion of pediatric patients when asymptomatic cases are included. It is also known that urinary stones can occur in severely disabled children with or without epilepsy. In this study, we hypothesized that severely disabled children treated with TPM would have urinary stones at a higher rate, and we evaluated urinary stones radiologically in severely disabled epileptic children treated with TPM. Methods:  We reviewed the medical records of severely disabled, epileptic and bed-ridden children showing severe mental delay, who were treated with TPM. The patients underwent ultrasonography (US) or computed tomography (CT), to assess for the presence of for urinary stones, at Hiroshima University Hospital from January 2016 to May 2017. Subjects with and without clinical symptoms were included. Results:  Eight patients (five males, three females; age range: 4–13 years) were enrolled. Dose and treatment duration of TPM varied from 80 to 260 mg, and from 1 to 6 years, respectively. Urinary stones were found in five patients. They were detected by US in four cases and by CT in one. Macrohematuria was observed in two cases. Apparent metabolic acidosis was found in two cases among the five patients with urinary stones. Conclusions: Severely disabled children often also suffer from intractable epilepsy, against which TPM can be an effective drug. Some effect of TPM on epilepsy was seen in our cohort, but the management of adverse drug effects is also important. Although the dose of TPM and presence of metabolic acidosis did not necessarily affect urinary stone formation in our study, it is presumed that the risk of urinary stones may be increased in severely disabled children treated with TPM. Thus, we need to keep in mind the possibility of urinary stones when treating such patients. Funding: No funding.