Bacteriology of Blood and Joints in Chronic Infectious Arthritis.

Abstract

During the past 2 years, we have been making a bacteriological study of patients suffering from chronic deforming arthritis, giving special attention to cultures of the blood and joints. The technique employed for blood cultures is as follows: 20 cc. of blood are taken aseptically from the arm with a Luer syringe, placed in 2 sterile culture tubes, allowed to clot, and put in the icebox overnight. In the morning the tubes are centrifuged, and the serum drawn off with a sterile pipette. Care is taken to remove all the serum. The clot is then broken up in the original tube with a sterile glass tube, diameter 1/4 inch, drawn up in the same tube, and transferred to a 3 oz. bottle containing 50 cc. broth (beef-heart infusion broth, 0.5% saline, 1% peptone, pH 7.6). The two bottles are then put in the incubator at 37° and left there unopened for 5 days. At the end of this time, 2 tubes, each containing 8 cc. of a 1.5% beef-infusion-broth-agar, are melted, partially cooled, and 0.5 cc. of whole rabbit's blood added to each tube. Each tube is then seeded with a loopful of broth culture and the contents poured into a petri dish. The plates are allowed to incubate for 24 to 48 hours. Pourplate cultures are repeated at 3 day intervals for 4 weeks unless the colonies appear sooner. All contaminated cultures are discarded. In the 56 cases studied of chronic infectious arthritis with swelling, 47 presented one or more characteristic fusiform fingers, while the remaining 9 had one or more swollen joints in various parts of the body. Of the 56 cases, 38 or 68% showed an atypical Streptococcus in the circulating blood. In the 14 cases studied of chronic infectious arthritis without swelling, 7, or 50%, were positive. 43 controls without exception yielded negative results. These controls included 16 cases of chronic degenerative arthritis, 6 rheumatic heart disease, 1 gonococcal arthritis, 1 gout, 13 patients having various other infections without joint symptoms, and 5 normal healthy individuals.