[Skip to Content]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address 34.226.244.70. Please contact the publisher to request reinstatement.
[Skip to Content Landing]
Other Articles
October 1, 1938

A MICROSCOPIC PRECIPITIN TEST FOR TYPING PNEUMOCOCCI

Author Affiliations

Baltimore

From the Department of Pathology and Bacteriology, Johns Hopkins University.

JAMA. 1938;111(14):1285-1286. doi:10.1001/jama.1938.72790400002008a
Abstract

The rapid typing of pneumococci is becoming increasingly important with the development of therapeutic serums for the various types. The Neufeld method is admirably suited when the organisms are present in sputum, but difficulties are encountered when typing is attempted from cultures. The macroscopic agglutination of cultures requires the use of pipets and test tubes, and the quantity of serum required represents considerable expense. We have employed a microscopic precipitin technic by which the pneumococci can be typed from cultures quickly and with a very small amount of immune serum. The technic proposed by Brown1 for grouping the hemolytic streptococci has been adapted for this purpose.

PREPARATION OF THE ANTIGEN  Cultures of pneumococci from blood, spinal fluid or other sources taken during life or at autopsy may be grown in meat infusion broth containing a few drops of serum or ascitic fluid2 incubated at 37 C. for from

×