January 1977

Detection of Endotoxin in Cerebrospinal and Joint Fluids by Limulus Assay

Author Affiliations

From the Division of Infectious Diseases, Department of Medicine, George Washington University Medical Center, Washington, DC (Drs Tuazon and Sheagren), Department of Pediatrics, DC General Hospital, Washington, DC (Dr Perez), and Laboratory of Clinical Investigation, National Institute of Allergy and Infectious Diseases (Dr Elin).

Arch Intern Med. 1977;137(1):55-56. doi:10.1001/archinte.1977.03630130039010

Cerebrospinal fluid (CSF) and joint fluid from 81 patients were studied for the presence of endotoxin using the limulus assay. All fluids that grew Gram-negative organisms had a positive limulus test. However, one sample of CSF and one of joint fluid, both very purulent, that contained Gram-positive organisms also gave positive limulus assays. All culturally negative fluids had a negative limulus assay. Thus, a positive limulus assay with CSF or joint fluid is indicative of bacterial infection probably caused by Gram-negative organisms and can be an extremely useful diagnostic adjunct.

(Arch Intern Med 137:55-56, 1977)