Proctitis associated with chlamydial infection in a koala.

Abstract

To describe proctitis associated with chlamydial infection in a koala. A pathological study. A free living, male koala aged 17 years. Rectum was examined histologically and chlamydial organisms visualised using Giminez' stain and an immunoperoxidase staining method using an anti-Chlamydia lipopolysaccharide (genus specific) antibody. An aged koala presented for euthanasia was found to have asymptomatic chronic proctitis, cystitis, prostatitis, urethritis and conjunctivitis associated with chlamydial infection. Inflammation was severe in the terminal rectum and extended into the proximal common vestibule. Chlamydial organisms were visualised in the rectal surface epithelium using Giminez' stain and an immunoperoxidase staining method. Organisms were also detected in the epithelium of the bladder, prostate and urethra. Possible modes of transmission for the rectal infection are direct sexual transmission or ascending infection by organisms shed from the urogenital tract into the common vestibule. Previously unreported chlamydial proctitis in the koala may represent a potential reservoir of infection for other koalas.