RISK FACTORS FOR UROLITHIASIS IN CHILDREN ON THE KETOGENIC DIET

Abstract

SUMMARY AND CONCLUSION T his prospective study was conducted on 20 patients with age ranging from 12-60 months (mean age 31± 8.67 months) diagnosed with symptomatic drug- resistant epilepsy. They were recruited from the Pediatric Neurology Outpatient Clinic, Children's Hospital Ain Shams University during the period from November 2012 till May 2013.the aim of this study was to clarify the risk factors for development of renal stones in drug –resistant Egyptian epileptic children on the ketogenic diet. All subjects underwent full history taking, clinical examination and laboratory investigation routine urine analysis, quantitative assessment of urine (urine calcium after overnight fasting, urine calcium to creatinine ratio) basally at 3 and 6 months. Frequency and severity of seizures assessed by Chalfont severity score were recorded. Following the start of the diet, all patients were hospitalized for 3 days to assure tolerance to the ketogenic diet and ketosis response. Also regular out patients visits were done every two weeks for 6 month, during which The patients ketones in urine was monitored, Seizure frequency and severity were recorded, toleration to the diet, any complications as nausea, vomiting, bowel disturbance, loin tenderness, dysuria and gross hematuria were recorded and managed, parents were instructed to observe the urine for hematuria. Our study results could be summarized as follow: • The demographic characteristics of our patients, the mean age of our patients was 31±8.67 months (range 12 -48 months), for the two patients who developed renal stones one patients was 26 months and the other was 36 months so from our results younger age at diet initiation was no longer a risk factor for renal stone formation. Sex of the patients for non stone former, 11(6%) of cases were males and 7(39%) of cases were females; while for the stone cases 1(50%) was male and 1(50%) was female. So patients gender not a risk factor for renal stones. • Family history of renal stones, for non stone former no family history of renal stones in 16(89%) of cases and 2(11%) had family history of renal stones; while for the stone former cases2(10%) there was no family history for renal stones in 1(50%) patients and 1(50%) had family history of renal stones. • Concerning the use of medications that may increase the risk of stone formation (topiramate and zonisamide), our two patients with renal stones have no history of usage of these medications. • The etiology of epilepsy, 4 patients (20%) was post anoxic, 6patients (30%) was post infectious, 3 patients (15%) was tuberous sclerosis and 7 patients (35%) was of unknown etiology. • Type of epilepsy 8 patients (40%) had generalized epilepsy, 9 patients (45%) had focal epilepsy and 3 patients (15%) had infantile spasm. • About 17 patients (85%) reported very good tolerance to the ketogenic diet some GIT symptoms as nausea and vomiting occurred in 2 of non –stone former patients (10%). Also 3 patients (15%) suffered from constipation. • Throughout the study, after 3 months; Loin pain was detected in 2(11%) of non - stone former cases, dysuria was detected in 1(6%) of non- stone formers and haematria was not detected in stone and non-stone former cases. After 6 months for non-stone former 2(11%) of patients suffered from loin tenderness and 1(6%) of patients suffered from dysuria, while for stone cases loin tenderness was detected in 1(50%) of two patients, 2(100%) of cases presented with dysuria and gross hematuria was reported in 1(50%) of cases. • The anthropometric measurements of our patients throughout the study showed that no significant change in mean Z score of weight of our patients occurred at 3 or 6 months. Regarding the length or height, there was a non significant increase in height from basal line when compared to mean height values at 6mns in both group. • Laboratory investigations, urine pH and urine specific gravity showed no difference between patients with stones and non- stone former patients after 3 months and also after 6 months. Hematuria was detected in two patients (100%) of stone former after 6 months which is the time of diagnosis of renal stones. Urine calcium after overnight fasting when comparing stone formers with non stone formers upon enrollment and after 3 months the results was normal in both groups while after 6 months, the results of urine calcium were within the normal reference range (< 0.16mg/ 100mLGF) in non stone formers and were elevated in stone cases. Regarding urine calcium to creatinine ratio when comparing stone formers with non stone formers upon enrollment and after 3 months was normal in both groups while after 6 months, the results of urine calcium to cretinine ratio were within the normal reference range in non stone formers and were elevated in stone cases.