1/11. Persistent damage to enterocytozoon bieneusi, with persistent symptomatic relief, after combined furazolidone and albendazole in AIDS patients.AIM: To investigate morphological changes in enterocytozoon bieneusi and the duration of symptomatic relief after combination treatment with furazolidone and albendazole in AIDS patients. methods: Four severely immunocompromised AIDS patients with symptomatic E bieneusi infection of the gut received an 18 day course of combined furazolidone and albendazole (500 800 mg daily). All patients were monitored for parasite shedding in stool by light microscopy at the end of treatment and monthly during follow up. At the end of treatment, duodenal biopsy specimens obtained from three patients were studied by transmission electron microscopy by two pathologists blind to the patients' treatment or clinical outcome. Duodenal biopsy specimens obtained from one of the patients two months after completion of treatment were also studied electronmicroscopically. RESULTS: All patients had long lasting symptomatic relief, with a major decrease--or transient absence--of spore shedding in stools from completion of treatment. After treatment, changes in faecal spores were persistently found by light microscopy in all cases, and there was evidence of both a substantial decrease in the parasite load and ultrastructural damage in the parasite in all biopsy specimens. The treatment was well tolerated, and no patient had clinical or parasitological relapse during follow up (up to 15 months). CONCLUSIONS: The long lasting symptomatic relief observed in all four treated patients correlated with the persistent decrease in parasite load both in tissue and in stool, and with the morphological changes observed in the life cycle of the protozoan. These data suggest that combined treatment with furazolidone and albendazole is active against E bieneusi and may result in lasting remission even in severely immunocompromised patients.- - - - - - - - - - ranking = 1keywords = cycle (Clic here for more details about this article) |
2/11. A case report of a hymenolepis diminuta infection in a child in St James Parish, jamaica.Hymenolepsis diminuta is a tapeworm which is an intestinal parasite of rats and mice. Rarely, through accidental ingestion of an infected arthropod, man can become the definitive host. This report documents, for the first time, that such infections occur in jamaica, west indies. The life cycle of the parasite and its treatment are also discussed.- - - - - - - - - - ranking = 1keywords = cycle (Clic here for more details about this article) |
3/11. dientamoeba fragilis: a bowel pathogen?Although many patients infected with dientamoeba fragilis suffer gastrointestinal symptoms, controversy still surrounds the pathogenic role of this intestinal protozoan. We describe three patients infected with D fragilis who had gastrointestinal symptoms. In the first patient symptoms resolved with therapy before the protozoan was eradicated from the stool, however in the second, symptoms persisted unabated despite clearing of the organism. In the third patient, symptoms resolution was associated with effective treatment. We discuss the life cycle, diagnosis and treatment of this organism and its role as a pathogen.- - - - - - - - - - ranking = 1keywords = cycle (Clic here for more details about this article) |
4/11. Overwhelming strongyloidiasis: an unappreciated opportunistic infection.strongyloides stercoralis is an intestinal nematode which infects a large portion of the world's population. Individuals with infection confined to the intestinal tract are often asymptomatic but may have abdominal pain, weight loss, diarrhea, and other nonspecific complaints. Enhanced proliferation of the parasite in compromised hosts causes an augmentation of the normal life-cycle. Resultant massive invasion of the gastrointestinal tract and lungs is termed the hyperinfection syndrome. If the worm burden is excessive, parasitic invasion of other tissues occurs and is termed disseminated strongyloidiasis. A variety of underlying conditions appear to predispose to severe infections. These are primarily diseases characterized by immunodeficiency due to defective T-lymphocyte function (Table 1). Individuals with less severe disorders become compromised hosts because of therapeutic regimens consisting of corticosteroids or other immunosuppressive medication. The debilitation of chronic illness or malnutrition also predisposes to systemic stronglyloidiasis. The diagnosis of strongyloidiasis can be readily made by microscopic examination of concentrates of upper small bowel fluid, stool, or sputum. Important clues suggesting this infection include unexplained gram-negative bacillary bacteremia in a compromised host who may have vague abdominal complaints, an ileus pattern on X-ray, and pulmonary infiltrates. eosinophilia is helpful, if present, but should not be relied upon to exclude the diagnosis. The treatment of systemic infection due to strongyloides stercoralis with either thiabensazole 25 mg/kg orally twice daily is satisfactory if the diagnosis is made early. Because of several unusual features of this illness in compromised hosts, the standard recommendation for 2 days of therapy should be abandoned in such patients. Immunodeficiency, corticosteroids, and bowel ileus reduce drug efficacy. Thus a longer treatment period of at leuch as blind loops or diverticula necessitate longer treatment. Stool specimens and upper small bowel aspirates should be monitored regularly and treatment continued several days beyond the last evidence of the parasite. In particularly difficult situations where either worm eradication is impossible or reinfection is probable, short monthly courses of antihelminthic therapy seem to be effective in averting recurrent systemic illness. Finally, prevention of hyperinfection or dissemination due to strongyloides stercoralis can be accomplished by screening immunocompromised hosts with stool and upper small bowel aspirate examinations. These would be especially important prior to initiating chemotherapy, or before giving immunosuppressive medications or corticosteroids to patients with nonneoplastic conditions such as systemic lupus erythematosus, nephrotic syndrome, or renal allografts.- - - - - - - - - - ranking = 1keywords = cycle (Clic here for more details about this article) |
5/11. cryptosporidiosis of the human small intestine: a light and electron microscopic study.Intestinal infection by the coccidian parasite cryptosporidium is a well-recognized condition in immunocompromised hosts and in some normal persons. The authors studied a patient with acquired immunodeficiency syndrome and cryptosporidiosis of the small intestine. The parasite inhabits the microvillous brush border of the intestinal epithelium and must be carefully sought on light microscopic examination of intestinal biopsy specimens. Characteristic life cycle stages are observed on electron microscopy. The absence of significant light microscopic alterations of the villous architecture in this patient's biopsy specimen and in other cases suggests that other factors, such as toxin elaboration by cryptosporidia or other organisms, may be involved in the pathogenesis of diarrhea. Abnormal aggregation of lysosomes at the apices of intestinal epithelial cells may reflect ineffective host phagocytic mechanisms.- - - - - - - - - - ranking = 1keywords = cycle (Clic here for more details about this article) |
6/11. strongyloidiasis in immunosuppressed hosts. Presentation as massive lower gastrointestinal bleeding.Two cases of massive lower gastrointestinal hemorrhage in immunosuppressed patients were due to complicated infestation with strongyloides stercoralis. The very high mortality of disseminated strongyloidiasis may in part be attributed to delays in diagnosis and treatment resulting from the complex life cycle of this nematode. Successful therapy in the cases presented consisted of reduction of corticosteroid dosage, use of thiabendazole in excess of that recommended for uncomplicated infestation, parenterally administered nutrition, multiple transfusion of blood products, and vigorous supportive management. Emphasis is given to proper categorization of patients and measures designed to prevent, detect, and treat hyperinfection in patients in whom immunosuppression is anticipated.- - - - - - - - - - ranking = 1keywords = cycle (Clic here for more details about this article) |
7/11. Intractable diarrhea of infancy due to intestinal coccidiosis.Intestinal coccidiosis in a 6-mo-old infant terminated fatally after 30 wk of continuous total parenteral nutrition, and proved refractory to treatment with antibiotics, hydrocortisone, and antimetabolic agents. Intestinal biopsies obtained at laparotomy revealed flattened mucosa infiltrated with coccidia at various stages of the parasites' life cycle. The course was characterized by severe diarrhea due to a cholera-like hypersecretion of intraluminal fluid. This case suggests that intestinal coccidiosis may be included among the small number of conditions responsible for authentic "intractable diarrhea of infancy."- - - - - - - - - - ranking = 1keywords = cycle (Clic here for more details about this article) |
8/11. Intestinal microsporidiosis in patients with acquired immunodeficiency syndrome--report of three more German cases.Intestinal microsporidiosis with enterocytozoon bieneusi was diagnosed in three of 18 hiv-infected patients with chronic diarrhoea. In two cases all known stages of the life cycle of E. bieneusi (merogonial plasmodia, sporogonial plasmodia, sporoblasts, spores) were found in duodenal biopsies by electron microscopical examination, whereas in the third case only merogonial and sporogonial stages were seen. spores were also visible by light microscopy in semithin sections. Two patients were treated with albendazole (2 x 400 mg/day for 4 weeks) but showed no response. These findings underline the concept of the worldwide distribution of this parasite and verify that it is also frequent in germany.- - - - - - - - - - ranking = 1keywords = cycle (Clic here for more details about this article) |
9/11. light and electron microscopic identification of cyclospora species in the small intestine. Evidence of the presence of asexual life cycle in human host.This is the first case of cyclosporiasis in which the parasite was clearly demonstrated in a duodenal biopsy by light microscopy. Electron microscopy identified the stages of sporozoite, trophozoite, schizont, and merozoite. Although only asexual forms were identified in our case, the sexual cycle must have taken place in the human host, because oocysts were detected in stools of the patients. Therefore, it appears that cyclospora species require only a single host to complete its entire life cycle. Despite the heavy infection, only enterocytes were invaded. The lamina propria and submucosa were not involved. The morphology of cyclospora in the intestine is similar to that of isospora, but differs from that of cryptosporidium. The morphology of the oocyst of cyclospora resembles that of cryptosporidium, but differs from that of isospora. Thus, a combined study of both stool and intestinal biopsy should readily distinguish cyclospora from cryptosporidium and isospora.- - - - - - - - - - ranking = 6keywords = cycle (Clic here for more details about this article) |
10/11. encephalitozoon (Septata) intestinalis: cytologic, histologic, and electron microscopic features of a systemic intestinal pathogen.encephalitozoon (Septata) intestinalis affects AIDS patients with CD4 counts <100/microL, causing intestinal and disseminated disease. It must be distinguished from the more common intestinal microsporidian, enterocytozoon bieneusi, and from other microsporidia of extraintestinal tissues, such as encephalitozoon hellem and E cuniculi, because clinical manifestations and treatment differ. In this report, the authors describe the diagnostic features of E intestinalis and illustrate all stages of its life cycle as exemplified by a case studied in detail. spores can be detected by light microscopy in feces, urine, or nasal secretions, but not identified to species. A presumptive tissue diagnosis of E intestinalis can be made if 20 to 50 organisms 1.2-2.5 microm in diameter are seen within vacuoles in enterocytes. The diagnosis is substantiated if organisms also are present in stromal cells. On electron microscopy, the septate parasitophorous vacuole is pathognomonic. E bieneusi occurs only in intestinal and biliary epithelial cells, and never within a vacuole. E hellem and E cuniculi, which are not intestinal pathogens, may cause systemic infection but develop in a nonseptate vacuole.- - - - - - - - - - ranking = 1keywords = cycle (Clic here for more details about this article) |
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