IMMUNOGLOBULIN SUBCLASS DEFICIENCY AND AL TERED EXPRESSION OF MONOCYTE LPS-RECEPTOR CD14 IN RENAL GRAFT RECIPIENTS - ASSOCIATION WITH CHRONIC URINARY-TRACT INFECTION

To elucidate possible immunological factors responsible for the outbre ak of urinary tract infections (UTI) IgG-subclass concentrations were assessed by ELISA in serum specimens from 26 renal transplant recipien ts (22 women, 4 men) suffering from chronic recurrent UTI. 20/26 patie nts received ciclosporin A and prednisolone as immunosuppressive agent s. Urological diseases facilitating UTI were excluded. 76 healthy subj ects and 11 graft recipients with an uncomplicated course served as co ntrols. The most frequent uropathogens cultured from urine specimens o f NTX-pts. with UTI were E. coli, staphylococci, enterococci, and stre ptococci. In general, transplant patients (without UTI) revealed a dec rease of all IgG subclasses compared to the controls (p < 0,01). Immun oglobulin-subclass serumconcentrations of IgG1 and IgG2 were further r educed in the group of UTI-patients (p < 0,05). In addition, quantitat ive cytoflowmetric analyses of blood monocytes disclosed that the expr ession of the monocyte endotoxin receptor CD14 was significantly decre ased in renal transplant patients, thus indicating that not only humor al bur also cellular factors may contribute to UTI in immunocompromise d patients.