Using the commercial antigen now available and the method described above, the complement fixation test appears to be of diagnostic value in hepatic amebiasis. A positive test is of considerable significance although negative results may occur in clinically proven cases. The complement fixation test as performed was of no value in the diagnosis of intestinal amebiasis; the sera of only 2.4 per cent of persons harboring E. histolytica in their stools gave a positive reaction. This may be an advantage, however, for the common occurrence of intestinal amebiasis does not confuse the diagnosis of amebic hepatitis by a positive complement fixation test.
Sera from patients with the following diseases gave negative amebiasis complement fixation tests: malaria, visceral leishmaniasis, Echinococcus cyst of the liver, infectious hepatitis, cirrhosis of the liver, carcinoma of the liver, cholecystitis, infectious mononucleosis, intestinal carcinoma, rickettsialpox, sprue, syphilis, ascariasis, and trichiniasis. Sera from single patients with clonorchiasis, malaria, chromoblastomycosis, and proctitis-sigmoiditis gave false positive reactions which in general were weak.
School of Public Health, Columbia University, 600 West 168th St., New York 32, N. Y.