IgA deficiency and neutropenia

That the anuria was apparently painless yet due to bilateral obstruction of the ureters by calculi is noteworthy. Herring,4 in a study of 10 000 urinary calculi, found only 89 to contain cystine, of which about 700,, were composed of pure cystine, as in our case. Thus urinary tract calculi may be due to cystinuria even in a young child. Cystinuria5 is a recessive or incompletely recessive genetic abnormality. Urinary concentrations of cystine, lysine, arginine, ornithine, and cystine-homocysteine are raised. Cystine, the least soluble of the urinary amino-acids, tends to precipitate when present in excessive concentrations. Cystine stones, however, occur only in some cystinuric patients, who may develop them presumably either in utero or during infancy, but the precise reasons for their formation are uncertain. Predisposing causes such as infection or anatomical abnormalities of the urinary tract are unusual. Most medical treatments aim at reducing the concentration of urinary cystine. Penicillamine or a "high fluid intake" may cause dissolution of cystine calculi, but the immunological abnormalities induced by penicillamine, hypertension, heart failure, electrolyte disturbances due to fluid and alkali excess, and impaired renal function are important considerations in management. Our aim in this patient is to prevent further stone formation and avoid electrolyte imbalance. We are reluctant to use penicillamine because of its side effects.