Ketogenic Diet Therapy (KDT) and Nutritional Status in a Glut 1 Deficiency Syndrome (G1DS) Chilean Cohort

Background: GLUT1DS is an early onset childhood epileptic encephalopathy caused by impaired glucose transport across the blood brain barrier with subsequent brain energy failure symptoms, primarily seizures, cognitive impairment, and movement disorders. Since its initial description in 1991, the number of affected individuals has increased with age specific symptoms across lifespan. KDT has been proven as an effective treatment that should be initiated as early as possible, providing the developing brain with alternative metabolic fuel (ketones). Objective: Describe anthropometric and biochemical status of patients with GLUT1DS on KDT. Methods: Medical records of all patients on our GLUT1DS follow-up program were reviewed. Patients were appointed for anthropometric and biochemical evaluation. Lipid profile, serum ferritin and 25OHvitD was obtained. Insufficient D vitamin status was defined with levels between 20-30ng/ml and deficiency with levels below 20ng/ml. In children 5y, BMIz-score was used. Height adequacy was evaluated with height for age (HFA)z-score. Results: 20 patients (11 male), with a median age of 7.9y who had been on KDT for a median of 2.7y (range 3m-21y) were evaluated. All of them with adequate supplementation. In 9 subjects, KDT was initiated within the first 7d since diagnosis; 9 were started within 1m and only 2 were started at 3m since diagnosis due to family issues. After KDT initiation, all patients responded with >50% reduction of seizure activity, 12 of them becoming seizure-free. However, accurate diagnosis was delayed a median of 3y since the first seizure episode (range 15d-13y). Ratio of KDT was between 2-2.7:1 in 11 subjects; 3 were following a MAD diet, 3 had a ratio of 1.5:1 and 2 had a ratio >3:1. Ketone levels (BOHB) were between 0,5-2 mmol/lt in MAD diet users, and between 2-3.9 mmol/lt in the rest of subjects. Six patients were classified with normal weight, 8 with overweight, 3 with obesity and 2 underweight. Two patients had short stature (z-score: -2.65 /-2,4). All subjects had normal iron deposits. Three subjects had insufficient vitamin D levels and 3 had deficiency status. 4 patients had elevated LDLc (range 116-130 mg/dl), 3 had low HDLc (34-38 mg/dl) and 4 had elevated triglycerides (137-165 mg/dl). Conclusions: KDT is an effective nutritional medical therapy for GLUT1DS which renders a good seizure control with limited impact on mi