Urolithiasis in an African population.

Eighty-one cases of urinary tract calculi in Nigerians seen at the University of Nigeria Teaching Hospital, Enugu, Nigeria, over a period of five years are reviewed. A relative incidence of 13 per 100,000 was established. At the time of presentation, 36 stones were found in the bladder, 21 in the kidneys, 20 in the ureters, one in the prostate and 3 in the urethra. Five patients had calculi at multiple sites. There was a male to female ratio of 5 : 1. Forty-one per cent of the calculi occurred in the 31-40 year age group, and 14.8% of cases were found in children. Over 80% of the calculi were secondary to obstruction, infection and immobilization. Only 15% were idiopathic. Urinary tract stone disease is rare in the Negroid race, as confirmed by this study on Nigerians. Avenues for further studies are suggested.