Impact of L-carnitine supplementation on gastric emptying and bowel function in pediatric ketogenic diet therapy: a clinical trial

Ketogenic diet (KD) is an excess fat, enough protein, and minimal carbohydrate diet. The high fat content in KD lowers the oesophageal sphincter tone, slows gastric emptying, and decreases intestinal transit time. The primary aim of the current clinical trial was to study the effect of L-carnitine supplementation on gastric emptying in children with drug resistant epilepsy (DRE) on KD. Assessment of the protective effect of L-carnitine on bowel function and habits in those patients was a secondary aim. The current study recruited 30 patients aged 12 months to 18 years newly diagnosed with DRE assigned to start KD who were following up at the Pediatric Clinical Nutrition and Neurology Outpatient Clinics or were admitted due to DRE at the Pediatric Neurology Inpatient Department, Children's Hospital, Ain Shams University (Egypt). Participants were assigned randomly into 2 arms; arm I: received KD with L-carnitine supplementation, arm II: received KD only. Patients were assessed at baseline and after 3 months of starting KD, the assessments of children included: 24-hour dietary recall, Chalfont Seizures Severity Scale, gastrointestinal symptoms score and Bristol stool chart, frequency of defecation per week, anthropometric measurements assessment, fasting serum lipid profile and measurement of the antral length by ultrasound. There was significant increase in antral length in the patients who received KD with L-carnitine supplementation compared to the non-supplemented group. The antral length showed a significant negative correlation with GI symptoms score in all cases and the L-carnitine supplemented group. It also showed a significant positive correlation with Bristol stool score in all patients and a significant positive correlation with stool frequency in the L-carnitine supplemented group only. L-carnitine supplementation to children with DRE on KD has a significant role in improving gastric motility and it increases the frequency of defecation. Further studies are recommended to explore additional benefits, meanwhile it is prudent to advise L-carnitine supplementation for such patients.