Efficacy of L-Carnitine on 24-Hour Urine Metabolites in Patients with a History of Recurrent Stone Formation

Kidney stones are one of the most common health problems in developed countries. A significant number of these populations experience recurrent stone formation with pain, urinary tract infection, or decreased parenchyma and renal function.

Accordingly, the aim of this study was to evaluate the effect of L-carnitine on 24-hour urine metabolites in patients with a history of recurrent stone formation.

This study was conducted on patients with recurrent stone formation. After the study samples were selected, they were provided with the necessary information about the study and their medical status. Demographic data and 24-hour urine indicators (including calcium, oxalate, uric acid, and citrate) were recorded before treatment. Patients were followed up for two weeks with no drug treatment and a regular food diet. At the end of the two weeks, 24-hour urine samples were collected and evaluated for calcium, oxalate, uric acid, and citrate. Patients were then treated with L-carnitine for eight weeks, with a dose of 1 gr daily. At the end of the eighth week, 24-hour urine samples were collected and evaluated for calcium, oxalate, uric acid, and citrate. Finally, the data obtained from this study were statistically analyzed.

34 individuals with a mean age of 39.5 ± 11.8 years participated in the study.11 patients (32.3%) were female, and 23 patients (67.7%) were male. The mean weight of the patients was 69.7 ± 10.6 kg of the mean size of the renal stones before and after treatment was 3.8 ± 3.1 and 3.6 ± 3.2 mm, respectively (P = 0.92). Moreover, the mean levels of uric acid, oxalate, citrate, and calcium before treatment were 748.3 ± 368.8, 28.9 ± 15.0, 945.5 ± 751.3, and 172.2 ± 116.1, respectively. The mean values of these urinary metabolites after treatment were 482.0 ± 266.7, 23.0 ± 13.1, 837.6 ± 609.9, and 134.8 ± 103.0, in the same order. A statistically significant decrease in the levels of uric acid, oxalate, and citrate is thus observed (P ≤ 0.05). Although calcium levels decreased after treatment, this reduction was not statistically significant (P = 0.08).

Treatment with L-carnitine, although did not result in a smaller size of the stones, decreased the urinary metabolite levels. This reduction may be effective in reducing the recurrence of stone formation.