Nephrolithiasis associated with the ketogenic diet.
OBJECTIVE
The ketogenic diet has been used for treating seizure disorders for more than 70 years. Nephrolithiasis is a known complication of this diet with a reported stone rate as high as 10% but there is sparse literature detailing the nature and treatment of these stones. We report on 4 children with nephrolithiasis on this diet.


METHODS
We describe stone treatment and analysis as well as metabolic and urine abnormalities in 4 children with nephrolithiasis on the ketogenic diet who presented to our institution.


RESULTS
All patients were treated with shock wave lithotripsy, fluid liberalization and oral citrate. One child was ultimately withdrawn from the diet due to persistent stone formation. Analysis revealed 3 calcium and 1 ammonium urate stones. Three patients had hypercalciuria, 2 elevated urinary uric acid and 1 hypocitruria. Serum studies revealed acidosis in 3 cases.


CONCLUSIONS
The ketogenic diet induces several metabolic abnormalities that increase the propensity for stone formation. Urologists should be aware of this potential complication. Fluid liberalization and bicitrate are recommended as prophylaxis.
Kielb
S
S
Section of Urology, Department of Surgery, University of Michigan Medical Center, Ann Arbor, Michigan, USA.
Koo
H P
HP
Bloom
D A
DA
Faerber
G J
GJ
D002118:Calcium / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D004041:Dietary Fats / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007223:Infant; D007657:Ketone Bodies / Q000378:metabolism*; D007669:Kidney Calculi / Q000737:chemistry / Q000209:etiology*; D008297:Male; D012640:Seizures / Q000178:diet therapy
D004041:Dietary Fats; D007657:Ketone Bodies; D002118:Calcium