The significance of pleuropneumonia-like or L organisms in non-gonococcal urethritis, Reiter's disease, and abacterial pyuria.

The first member ofthe group ofpleuropneumonia organisms was isolated by Nocard and Roux in 1898 from cases ofcontagious pleuropneumonia of cattle, a disease in which the essential pathological lesions are gross pulmonary cedema, pleural exudate, and arthritis. A similar organism was found by Bridre and Donatien (1923, 1925) in sheep and goats suffering from agalactia, a syndrome which includes mastitis, arthritis, keratitis, and vesiculo-pustular skin lesions. Since 1935, when Klienberger isolated another strain from cultures of rats infected with Streptobacillus moniliformis, a number of organisms of the same group, usually referred to as pleuropneumonia-like or "L" organisms, have been described as causing arthritis, abscesses, pneumonia;