THE AMOEBAE 



141 



Cultivation : E. histolytica was first 

 cultivated by Boeck and Drbohlav (1925). 

 Their medium was composed essentially 

 of a coagulated egg slant overlaid with 

 Locke's solution containing serum. Var- 

 ious modifications of this medium are 

 still in use. Cleveland and Collier (1930) 

 used a liver infusion agar slant overlaid 

 with serum and physiological salt solution. 

 Balamuth (1946) introduced an all-liquid 

 egg infusion-liver extract medium. 



Treatment : Amoebiasis can be 

 treated with a number of drugs (cf . Bala- 

 muth and Thompson, 1955). The old stand- 

 ard drug, emetine, is not used as much as 

 formerly because of its toxicity. Other 

 drugs from which one can choose include 

 (1) the arsanilic acid derivatives, carbar- 

 sone, glycobiarsol (bismuth glycoarsani- 

 late, Milibis) and thiocarbarsone; (2) the 

 iodoquinoline derivatives, diodohydroxy- 

 quin (Diodoquin), chiniofon (Yatren) and 

 iodochlorhydroxyquin (Vioform); (3) the 

 antimalarial drug, chloroquine; and 

 (4) the antibiotics, erythromycin, fuma- 

 gillin, tetracycline, chlortetracycline and 

 oxytetracycline. 



The particular drug selected depends 

 in part on the type of amoebic infection 

 involved. For acute or subacute dysen- 

 tery, erythromycin, oxytetracycline or 

 chlortetracycline may be used. Erythro- 

 mycin is administered to man by mouth at 

 the rate of 15 mg/kg daily in divided doses 

 for 14 days. The usual human course of 

 treatment with oxytetracycline or chlor- 

 tetracycline is 0. 5 g 4 times a day by 

 mouth for 10 days. 



For chronic cases or to eradicate in- 

 testinal infections, one of the arsanilic 

 acid or iodoquinoline derivatives may be 

 used. The usual adult human course of 

 treatment with carbarsone is 0. 25 g 2 or 

 3 times a day by mouth for 10 days. That 

 with glycobiarsol is 0. 5 g 3 times a day by 

 mouth for 8 days. That with chiniofon is 

 1. g 3 times a day by mouth for 7 days. 

 That with diodohydroxyquin is 0. 65 g 3 

 times a day by mouth for 20 days. 



For amoebic hepatitis or liver ab- 

 scesses, chloroquine is used. A loading 

 dose of 1 g chloi'oquine phosphate (0.6 g 

 base) by mouth on each of 2 successive 

 days followed by 0. 5 g daily for 2 to 3 

 weeks is the recommended adult human 

 course of treatment. 



Diodohydroxyquin has also been rec- 

 ommended as a prophylactic drug for use 

 by travellers in ai-eas of high endemicity. 



While relatively little work has been 

 done on the treatment of amoebiasis in 

 domestic animals, the same drugs are in 

 general effective in them. Benson, Frem- 

 ming and Young (1955) found that for chim- 

 panzees the most successful drugs were 

 carbarsone (0.25 g twice daily for 10 

 days) and fumagillin (20 to 30 mg twice 

 daily for 10 days) administered in fruit or 

 fruit juice. They also frequently gave a 

 course of emetine hydrochloride (1 mg/kg 

 body weight up to a maximum of 60 mg, 

 injected intramuscularly daily for a max- 

 imum of 6 days) prior to carbarsone or 

 fumagillin therapy (see also Fremming 

 et al. , 1955). Herman and Schroeder 

 (1939) successfully treated amoebic diar- 

 rhea in a 21 -lb. orang-utan with carbar- 

 sone. They gave 2 courses of treatment 

 11 days apart, each course consisting of 

 0. 05 g carbarsone in milk or a slice of 

 banana 3 times a day for a week. 



Prevention and Control : Infection 

 with amoebae can be prevented by sanita- 

 tion. Water supply systems should be 

 built without cross connections to sewage 

 systems. Water which may be polluted 

 should be boiled or filtered thru sand, 

 since ordinary chlorination does not kill 

 the cysts. Food handlers should wash 

 their hands thoroughly after using the toi- 

 let. Vegetables grown on polluted ground 

 should be cooked, or, if they are to be 

 eaten raw, should be scalded or soaked in 

 vinegar containing 5% acetic acid for 15 

 minutes at 30° C or in vinegar containing 

 2. 5% acetic acid for 5 minutes at 45° C 

 (Beaver and Deschamps, 1949). Diodohy- 

 droxyquin may also be used prophylactically. 



