Experimental induction of strongyloides autoinfection

Laboratory studies on the Jamaican strain of human Strongyloides employed the mongrel puppy as a model for the exploration of aspects of host Strongyloid relationships. Autoinfection was experimentally attempted by obstruction of the gut in various ways. The results indicated that a model for autoinfection was successfully elicited in the puppy. Under defined conditions, prednisone therapy and a protein-restricted diet failed to induce autoinfection. By contrast, chemically induced constipation, vincristine therapy, arterial occlusion and ileal ligation evoked autoinfection, luminal rhabditiform larvae having metamorphosed to filariform larvae and disseminated to the Auerbach plexus, the wall of the gut generally, the lung and the lymph node. A hypothesis is tentatively advanced to explain the etiology of autoinvasion (AU)

Hyperinfection syndrome with Strongyloides stercoralis in malignant lymphoma

Hyperinfection with Strongyloides stercoralis occurred in three patients with malignant lymphoma. The probable cause was alteration of the immune responses either as a result of the malignant lymphoma or by the treatment given. Though thiabendazole (Mintezol) has produced reasonable results in the treatment of the hyperinfection syndrome, preliminary data suggest that the new broad-spectrum antihelmintic levamisole (Ketrax) is more effective. All patients who live or have lived in an area where strongyloidiasis is endemic should be investigated to detect the presence of the nematode before and during treatment with drugs with immunosuppressive properties. In view of the high mortality with S. stercoralis hyperinfection, vigorous therapy should be instituted before the use of immunosuppressive drugs (Summary)

Laboratory and field studies on the Jamaican strain of human Strongyloides

Laboratory and field studies were done on the Jamaican strain of human Strongyloides. In the laboratory, optimal conditions for propagations of the free-living cycle were investigated. The mongrel puppy was employed as a model for the exploration of various aspects of host-strongyloid relationships. The histological reaction to normal skin to penetrating larvae, and of sensitised skin to larvae, excretory-secretory ("ES") and somatic ("S") antigen, was determined. Enzymatic activities of falariform larvae were assayed in vitro. Several factors predisposing to autoinfection were examined. The anthelmintic activity of levamisole and thiabendazole was compared. In the field, a follow-up study was done and pilot surveys for prevalence were conducted throughout Jamaica in areas contrasting in climatic and physiographic features. The results indicated that optimal conditions for propagation of the heterogonic cycle existed at a temperature range of 26§C to 30§C, a pH range of 7.5 to 8.0, and a stool consistency equal to that of a very thick paste. The reaction of normal skin to invading larvae was essentially a non-specific, acute inflammatory response; with sensitised skin, there was significant degranulation of mast cells in the presence of larvae, "ES" and "S" antigen. Collagenase, galatinase, fibrinase, lipase and hyaluronidase activity of falariform larvae were demonstrated. Autoinfection was experimentally induced by constipation, by vincristine therapy, by ileal ligation and by simulation of ileal volvulus. A general hypothesis was advanced to explain the etiology of autoinfection. Levamisole possessed statistically significantly greater anthelmintic activity than thiabendazole against Strongyloides in vitro, but not in vivo in puppies. It was unable to eradicate the parasite completely from the stools of five out of six infected patients. Preliminary data suggest that the chronicity of strongyloidiasis in Jamaican patients is due to internal autoinfection rather than external reinfection. The low prevalence of the infection in the general population is very low (30 out of 1,555 persons positive, or 1.9 percent)(AU)

Hyperinfection with strongyloides stercoralis - abstract

A combination of the history, clinical signs and the presence of a high proportion of the invasive filariform larvae, is sufficiently diagnostic of Strongyloides stercoralis hyperinfection. Early recognition and effective treatment of this condition can avoid the occasionally associated mortality. The clinical, laboratory, radiological and histological aspects of 23 patients with the condition seen at the University Hospital of the West Indies and not previously reported, are presented. The course of hyperinfection was found to be predominantly a chronic one, in which the prevalence of abdominal pain, weight-loss, vomiting and hypoalbuminaemia was greater than 90 percent but was acute and fulminating in 3 cases. The overall mortality was 35 percent. Radiological abnormalities were maximal in the duodenum and jejunum, mucosal cedema, dilation and reverse peristalsis being commonest. Treatment with conventional drugs did not uniformly cause complete eradication of the organism, but in vitro, in vivo and clinical comparisons indicate that a new drug Levamisole is significantly more effective than Thaibendozole against strongyloides stercoralis (AU)

Clinical gonorrhea in the female: laboratory findings

This paper is very timely in its relationship to the current epidemic of gonorrhea in this country and as reported by the western nations. It emphasizes the difficulty in establishing the diagnosis of gonorrhea in women and girls without using cultures from the cervix and rectum. The new media soon available to the practising profession will be a boon in this regard. Mixed infections or infestations have been proven in instances of vaginitis. The smear is of little value alone. This study does not touch upon the high percentage of women infected with gonorrhea who are asymptomatic. (AU)