Pediatric urolithiasis in Armenia: a study of 198 patients observed from 1991 to 1999

To study prospectively the risk factors and etiology of urolithiasis in all stone patients aged <15 years admitted from 1991 to 1999 to the Arabkir ho spital in Yerevan. Stones were obtained by surgery (64%), extracorporeal sh ockwave lithotripsy (ESWL) (7%) or cystoscopic extraction (4%); 25% passed spontaneously. All were examined by infrared spectroscopy, and spot urines were analyzed chemically. 198 patients, 180 (68% males) with renal stones a nd 18 (83% males) with primary bladder stones, were studied. Calcium oxalat e (CaOx) was the predominant constituent in 62% of the kidney stones, follo wed by struvite (17%), calcium phosphate (7%), uric acid (7%), ammonium aci d urate (5%), and cystine (2%). Bladder stones contained CaOx in 72%, uric acid in 22% and ammonium acid urate in 6% of patients. Etiology was obvious ly metabolic in 5% and possibly metabolic in 26%. Twenty percent of stones were infectious, and 19% were endemic (9% bladder and 10% kidney stones); 4 % were secondary to urinary stasis with malformation but no infection. Etio logy in 26% remained unknown. Stone composition and metabolic etiology are similar to that in central Europe and North America. In contrast, infectiou s calculi and particularly endemic stones are still common, although becomi ng less so now. Urolithiasis in Armenia thus reflects the transition from a rural to an urban society.