Search for mycoplasma in rheumatoid arthritis.

Since the infectious rat polyarthritis strain belonging to mycoplasma (previously named PPLO) was isolated by Findlay, Mackenzie, Mac Callum, and Klieneberger (1939), several attempts have been made to study their possible role in arthritis in man. Most of the results have been discouraging (Sabin and Johnson, 1940; Barnett, Balduzzi, Vaughan, and Morgan, 1966), but a few positive findings were published in the early literature (Swift and Brown, 1939; Dienes, Ropes, Smith, Madoff, and Bauer, 1948; Butas, 1957; Kuzell and Mankle, 1960). In the 1960s, both Jonsson (1961) and Arai, Ishikawa, and Hotta (1964) isolated mycoplasma directly on cell-free media from patients with polyarthritis, but made no attempt to distinguish them from L-phase organisms. Bartholomew and Himes (1964) and Bartholomew (1965) obtained his isolations of mycoplasma from rheumatoid arthritis, lupus erythematosus, and Reiter's syndrome after preliminary passage in tissue cultures. Highton, Caughey, Berkley, and Middleston (1966) isolated mycoplasma in a case of rheumatoid arthritis with a later increasing rheumatoid factor titre and progressive disease. Fahlberg, Moor, Redmond, and Brewer (1966) obtained mycoplasma from synovial tissues or fluids in 22 of 24 patients with rheumatoid arthritis. Williams (1968) found a mycoplasma serologically related to Mycoplasmafermentans in 40 per cent. of ninety synovial fluids from cases of active rheumatoid arthritis. His control series consisted of 26 cases, mainly of osteoarthrosis. From this group five mycoplasmas were isloated, one isolate being related to M. fermentans. In order to separate mycoplasma from other materials present in the specimen, Williams (1968) used a sucrose density gradient. Using cell-free media, we obtained in 1964 two strains related to Mycoplasma hominis type 2 (at present named Mycoplasma arthritidis) from one synovium and one joint fluid from two patients with definite Waaler-Rose-positive rheumatoid arthritis. A third strain was isolated from a scalene lymph node from a patient with an 8-year history of collagen disease who 3 years later developed a fatal myeloid leukaemia. A few patients with rheumatoid arthritis possessed antibodies against one of the strains isolated (Jansson and Wager, 1965, 1967). Further studies are reported in this paper.