Some Incidental Observations on the Possibility of a Virus as Part Causal Factor in Rheumatism.

THE following observations, though inconclusive, are recorded because they seem to have some relevance to the question of a virus as part causal factor in rheumatism. I. A case of multiple arthritis of some duration, with deformities and X-ray rarefaction (sedimentation rate unknown), developed a very acute exacerbation in one knee-joint. Fluid from this joint was sent to the author for examination. Films showed a number of polymorphonuclear leucocytes and some lymphocytes, but no organisms. Culture on a large selection of media, aerobically and anaerobically, showed no infection even after prolonged incubation. A portion of the fluid was injected intraperitoneally into a guinea-pig. This pig remained apparently well for three months, when it died quite suddenly. Post-mortem showed an extremely distended pericardium. No other lesion was observed. The fluid from the pericardium was dealt with in three ways: (a) It was injected direct into the peritoneum of another pig; (b) it was planted into broth containing chopped-up portions of the dead pig's spleen; (c) it was planted on to a blood-plate, and the colony growing on the plate was subcultured into broth. 0-2 c.c. of tenfold serial dilutions of (b), the first spleen-broth culture, and 02 c.c. of similar dilutions of (c), the broth sub-culture from the blood-plate, were injected into pigs. The following results were observed: 1. Pig injected with (a), the direct pericardial fluid, remained apparently well for two months, and then died suddenly as from acute heart failure, with P.M. appearance similar to the original pig. 2. Pigs inoculated with the spleen-broth culture died as follows: with the strong dilutions, they died of septicsemia within three days with no gross sign of pericarditis; with the weak dilutions they remained perfectly well for two to three months, and then died suddenly in the manner of the first pig with similar P.M. appearances. 15