A new method of study in vitro of the therapeutic effectiveness of the oxyquinoline drugs, Anayodin, Chiniofon, Diodoquin, and Vioform on Endamoeba histolytica has been attempted.
This was done by inoculating human serum-egg infusion media with known quantities of Endamocba histolytica and accompanying bacteria and determining the amount of growth at 48 hours. The first media contained serum obtained from the patient before taking the drug, the second contained serum of known iodine concentration obtained after 7 days treatment with the drug, and the third contained serum from a non-amoebic, non-treated control.
The sera from 15 patients taking Diodoquin, 11 patients taking Vioform, 2 taking Chiniofon, and 1 taking Anayodin were studied.
Serial dilutions were made of both Diodoquin and Vioform containing sera and the amount of growth at 48 hours determined.
The oxyquinoline drugs in the human sera appear to inhibit the growth of Endamoeba histolytica in vitro in inverse proportion to the iodine concentration. The concentration necessary to cause disappearance from the media of all amoebae at 48 hours apparently lies between 250 and 300 gammas.
Seven patients on Diodoquin for 7 days showed stool iodine concentrations approximately 250 times the serum concentrations of iodine. Fourteen patients on Vioform for 7 days showed stool iodine concentrations approximately 175 times the serum concentrations of iodine. Three patients on Chiniofon and Anayodin showed stool concentrations of approximately 425 to 700 times the serum concentrations. Control of all tendency to diarrhea enhances the absorption in man of the oxyquinoline drugs, Anayodin, Chiniofon, Diodoquin, and Vioform.
Assistant Clinical Professor of Medicine (Rush) University of Illinois Medical School, Chicago, Illinois.