topiramate and Nephrolithiasis

Topiramate is an approved drug to treat seizures, but its indications have been extended to other diseases of the nervous system and as an adjuvant to chronic pain. We present four cases of topiramate-induced nephrolithiasis from 2006-2012 in women whose treatment was prescribed for pain control and as a mood stabilizer at doses of 250-300 mg/day. In two cases, the lithiasis was caused by calcium phosphate (patite) and in the other two cases by oxalate and calcium phosphate. The most common metabolic alteration was an alkaline pH, followed by hypocitraturia. The drug was discontinued in two patient; it was reduced in one and was maintained in the fourth. An increase in fluid and potassium citrate intake was prescribed. In patients starting treatment with topiramate, an adequate control and prevention of nephrolithiasis should be performed due to the risk of mixed tubular acidosis and hypocitraturia. to the risk of mixed tubular acidosis and hypocitraturia.

Topics: Adult; Aged; Analgesics; Calcium Oxalate; Calcium Phosphates; Chronic Pain; Citric Acid; Female; Fructose; Humans; Hypercalciuria; Kidney Calculi; Middle Aged; Nephrolithiasis; Personality Disorders; Potassium Citrate; Psychotropic Drugs; Topiramate

Topiramate is a neuromodulatory agent increasingly prescribed for a number of neurological and non-neurological indications. Topiramate-treated patients are at risk for nephrolithiasis due to hypocitraturia and high urine pH. However, the prevalence of symptomatic stone disease in TPM users is generally perceived to be low. This study was undertaken to assess in topiramate-treated patients the prevalence of symptomatic nephrolithiasis (by history) and of asymptomatic nephrolithiasis by computed tomography (CT) scan. Topiramate users were identified from a database of patients with neurological disorders at a single university hospital. Among 75 topiramate-treated adult patients with a median daily dose of 300 mg and median treatment duration of 48 months, the prevalence of symptomatic nephrolithiasis was 10.7%. In a subset of topiramate-treated patients and no history of symptomatic stone disease, the prevalence of asymptomatic nephrolithiasis detected by CT scan was 20%. The prevalence of symptomatic nephrolithiasis with long-term topiramate use is higher than reported in short-term studies. Furthermore, clinical prevalence is underestimated due to asymptomatic nephrolithiasis.

Topics: Adult; Female; Fructose; Humans; Male; Middle Aged; Nephrolithiasis; Neuroprotective Agents; Prevalence; Prospective Studies; Retrospective Studies; Topiramate