Experience with urinary calculus disease in Nigerians as seen at the Lagos University Teaching Hospital.

The rarity of urinary calculus disease in this community was established by reviewing the cases seen in the Lagos University Teaching Hospital over an eleven year period and also by reviewing autopsy records of 5,022 patients. In the clinical review 45 stones were recorded in a period during which 636,735 Nigerian patients were seen in the clinics putting the incidence of stones in the urinary tract as 7 in 100,000. At the time the patients were seen, sixteen stones were located in the kidneys nine stones in the ureters, twenty two stones in the bladder and four in the urethra. Three patients had stones in multiple sites. In only nine patients (20%) were the stones idiopathic while the rest could be blamed on various forms of obstructive uropathy, stasis, infection or metabolic disorders. This contrasts sharply with stones in caucasians in which about 66% are idiopathic. Children and females were rarely affected by urinary stones. In the autopsy review, only two adult were found to have stones out of a total of 5,022 bodies. Although urinary calculi may be silent and remain undiagnosed, this low autopsy incidence indicates that stones are not just being missed in the clinics but that it is uncommon in this community.