Prognostic Value of the Precipitin Test in Meningococcus Meningitis

The occurrence of soluble specific substance of N. intracellularis in the spinal fluid in cases of meningococcus meningitis has been demonstrated by the precipitin reaction, but there is no record of an effort to correlate this reaction with the clin-ical severity or with the outcome of specific treat-ment of the disease in man. A review of reports of investigations carried out on the precipitin test is given by Rake (1); subsequently Maegraith (2) published additional data. An epidemic of meningococcus meningitis in Baltimore1 provided an opportunity for study of the spinal fluid in 69 cases. Antimeningococcus serum was administered intrathecally at least once in 24 hours until 2 negative cultures were ob-tained. Where there was an obvious invasion of the blood stream, serum was also used intra-venously. In an effort to evaluate the severity of each case, the following determinations were made on the first spinal fluid withdrawn from each pa-tient after admission to the hospital and before serum had been given: the spinal fluid cell count, sugar content, degree of phagocytosis and a rough estimation of the number of organisms present. The precipitin test was used in an attempt to esti-mate its value in rapid typing of the organisms. Early in the study, it became apparent that the intensity of the precipitin reaction was of prog-nostic value. It is with this specific problem that the present report will deal. The technique used for the precipitin test was that of the ring test carried out in tubes of small diameter in which centrifuged spinal fluid is care-fully layered on type specific precipitin sera (1). A rough quantitative estimation of the amount of specific soluble substance by the quantity of pre-'The author wishes to express appreciation and in-debtedness to Dr. Huntington Williams, Dr.