[The etiological factors in pyelonephritis occurring against a background of nephrolithiasis].

656 urine and 78 blood samples were examined immunomicrobiologically. No bacterial growth was recorded in 43.8% of urine samples. Opportunistic bacteria were represented by Enterobacteriaceae, nonfermenting gram-negative bacteria with predominance of E. coli, P. mirabilis, P. aeruginosa isolated both in monocultures and in associations in conventional diagnostic titers (1g 5 CFU/ml). Throughout 40 days of the hospital stay microflora continuously changed, but until the discharge the infection persisted. The study of the immunological aspect of anti-infection resistance showed that most of the examinees (73%) at admission with pyelonephritis exacerbation have deficient cellular and humoral defense.