Immunological and bacteriological studies in chronic pyelonephritis associated with kidney stones

Histological and immunofluorescent techniques, urine, stone and renal fragment culture, demonstration of bacteria with fluorescent specific antisera in the renal tissue and determination of circulating antiGBM and antiTBM antibodies in the serum, were studied on the renal biopsies of 46 patients with chronic pyelonephritis (CPN) associated to kidney stones. Results show that the bacteria are often present in renal tissue of CPN with negative urine culture. The presence of C3 and C4 in some cases, and C3 and C3PA in others, at the tubular level associated with bacteria, suggest that the activation of the C system may be through the classic way, i.e., through the bacteriological immune complexes, or the alternate pathway, i.e., through the bacteria or their products. In conclusion, the evolution of the CPN may be related to the activation of the C system and the coagulation mechanism, as shown by frequent fibrinogen deposits.