Incidence and Control of Amebiasis and other Intestinal Protozoan Infections in a Memphis Hospital

Abstract

Summary An incidence of amebiasis (E. histolytica) of 17 per cent among patients and personnel in a metropolitan hospital would suggest that this infection is more common than suspected fifteen years ago. The occurrence of trophozoites in more than half of the infected individuals, and a history of or symptoms of diarrhea or dysentery in more than one-third of the 42 cases of amebiasis, provide evidence of clinical significance. The greatest number of cases was among the housewife, food handler, and family groups. Many of the persons found infected were living in crowded dwellings in sections of the city where sanitary facilities were not always adequate. Memphis, and its surrounding areas, would appear to rank with other sections of the United States having a high incidence of amebiasis and similar community health problems. The need for adequate laboratory diagnostic facilities and personnel familiar with Heidenhain's iron-hematoxylin staining technic was apparent. The incidence of other protozoa was: Dientameba fragilis, 2.0 per cent; Giardia lamblia, 10.6 per cent; Endameba coli, 21.5 per cent; and Endolimax nana, 20.7 per cent among 246 people examined three or more times. There was a total of 2,061 stool specimens examined from 479 persons. All were inhabitants of the mid-south with the single exception of an ex-service-man. Thioarsenites (C.C. No. 914 and No. 1037), the dithiocarboxymethyl and dithiocarboxyphenyl derivatives of carbarsone oxide (C.C. No. 606) (carbamidophenylarsenous oxide), which had shown in vitro and in vivo activities, in previous laboratory tests, superior to those of currently-used amebacides, were employed in 40 patients. Except for nausea and/or vomiting after initial doses of 100 to 200 mgm. in tablet form, no other untoward effects were noted, except transient diarrhea in one. Salol coating of tablets controlled gastric distress when marked (5 of 6 persons). Others continued their medication without difficulty. Laboratory tests of blood, urine, stool and function tests of the liver and kidneys, as well as electrocardiographic tracings did not show evidence of systemic toxicity. Total dose levels ranged from 3.0 to 7.2 gm. given orally over 7 to 24 days. In four cases of dysentery, rectal application was also given of from 3.0 to 6.0 gm. (Drug No. 1037) over six days. Return of leukocyte counts to average range and significant elevations in hemoglobin levels occurred. An average of 12 stool specimens was examined during the four months' follow-up. The majority of patients having diarrhea or dysentery were cleared of their symptoms. All but two of 40 patients treated were cleared of their amebas. Fourteen individuals having giardiasis were given chloroquine, 2.2 mgm. per kilo orally, for seven days, with clearance of the flagellate in only three cases. There were five persons with pathogenic amebas who were not given the thioarsenites, and twelve others harboring giardia, who, without therapy, continued to show parasites during the follow-up period.