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Isospora belli, a coccidian parasite usually causes a self limiting illness of acute onset with fever, diarrhoea and colicky pain in a normal host. In immunocompromised patients human isosporiasis becomes chronic. We report a case of a malnourished 9 year old female child who presented with complaints of loose stools, nausea, vomiting and weight loss for the past three months. Stool examination revealed immature oocysts of Isospora belli. The patient was successfully treated with TMP-SMX.

We describe the first case of isosporiasis in a liver transplant patient. Watery diarrhea due to Isospora belli was observed in a woman who had undergone liver transplantation 8 months prior. She was successfully treated with trimethoprim-sulfamethoxazole. This parasite should be taken into consideration as an opportunistic infection in transplant patients who need increased hygienic awareness.

A 12-year old boy was presented as a case report. He had been diagnosed with isosporiasis during a field study, conducted in a village of Manisa province, during an investigation of the incidence of intestinal parasites.

A highly sensitive diagnostic method is of great importance for detection of I. suis (Isospora suis). In the present study KSFV (combined sedimentation-flotation method) using different flotation solutions (NaCl, ZnSO4, NaCl-sucrose) was investigated regarding sensitivity, costs and expenditure of human labour in comparison to FV (flotation method) using NaCl-sucrose solution and to AM (autofluorescence microscopy). Ninety faecal samples were examined. Using AM, oocysts were detected in 83.3% of the samples. In cases of KSFV and FV, respectively, 41.1% to 53.3% of samples were tested positive. The quantity of detected oocysts was markedly higher in AM than in KSFV or FV. Therefore AM is the most sensitive of the comprised methods. The expenditure of labour is lowest in AM, time exposure is lower in FV than in KSFV. For performance of AM a fluorescence microscope is required contrary to KSFV and FV.

To assess the prevalence of intestinal parasites in a cohort of human immunodeficiency virus (HIV)-infected adults in Cameroon, a cross-sectional study was conducted. Detection of parasites was performed in 181 stool samples from 154 HIV-infected patients with a mean CD4 cell count of 238 cells/mm(3). Only 35 patients (22%) were receiving antiretroviral therapy at the time of stool sampling, and 46 (29%) had diarrhea. Opportunistic protozoa were found in 15 patients (9.7%), 8 of whom (53%) had diarrhea. Enterocytozoon bieneusi was found in eight patients, C. parvum in six patients, and Isospora belli in three patients. All E. bieneusi isolates tested belonged to the same genotype. The prevalence of opportunistic protozoa among patients with CD4 cell counts less than 50/mm(3) was 32%.

Isospora belli infection is frequent in immunosuppressed patients and can cause wasting diarrhea. We present the first isosporiosis case in a renal transplant recipient from Turkey. The 25-year old male patient who had had a renal transplantation due to renal failure and had received immunosuppressive therapy presented at the hospital complaining of weakness, nausea, vomiting and diarrhea that had lasted for 15 days. Isospora belli oocysts were detected in stool samples by direct microscopy, modified Ziehl-Neelsen staining methods and autofluorescence technique. Oocysts in the stool samples were also sporulated in 2.5% potassium dichromate and the sporulated oocysts were seen microscopically. The patient was treated with co-trimoxazole (trimethoprim 160 mg, sulphamethoxazole 800 mg) every 12 hours for seven days, with elimination of the symptoms at this time. After this, Isospora belli oocysts were no longer seen in stool samples.

The authors describe a case of severe debilitating diarrhea due to isosporiasis in a two year old child, a known case of systemic vasculitis receiving prolonged corticosteroids therapy, an association rarely reported previously. It was refractory to treatment with dihydrofolate reductase inhibitor combined with sulfonamide such as cotrimoxazole to which isosporiasis usually responds well and is being described here for clinical interest and uniqueness of its presentation and laboratory findings.

This report describes a case of granulomatous endometritis caused by coccidiosis in an immunologically uncompromised 63 year old patient. The glandular epithelium of the endometrium contained numerous intracytoplasmic cysts, corresponding to periodic acid Schiff positive and methenamine silver negative sporoblasts. The endometrial glands revealed reactive phenomena, such as eosinophilic and squamous glandular metaplasia and intraluminal desquamation. Non-necrotising epithelioid granulomata, lacking the presence of parasites, were present in the stroma. Although not detected in the stool examination, the organisms were probably Isospora belli. There was no evidence of other foci of the disease. Coccidiosis should be differentiated from the more commonly occurring coccidiomycosis.

This report describes the presence of Isospora belli unizoic cysts in mesenteric lymph nodes and of gametocytes in the gallbladder epitelium of a 26 year-old Brazilian male patient with Acquired Immune Deficiency Syndrome. This patient had received treatment for several times with sulfamethoxazole-trimethoprim. It is discussed the significance of I. belli tissue cysts as possible foci of resistance of the parasite and their association with the infection relapse even post-treatment with anticoccidian medication.

Lacto-phenol cotton blue (LPCB) was found to be a useful stain for detection of Cyclospora and Isospora oocysts in direct wet mounts of stool. LPCB stained these parasites blue, and differentiated their internal structures clearly, thereby facilitating detection and accurate identification of these parasites. However, the LPCB staining was not found useful in the identification of Cryptosporidium. The LPCB wet mount is recommended for use in the laboratories where acid-fast staining is not performed routinely, such as in a peripheral laboratory or in a rural health centre in the developing countries.

The clinical, laboratory and therapeutic data of patients with diarrhea in Human immunodeficiency virus (HIV) antibody positive, immunocompromised and immunocompetent individuals were studied especially to look for prevalence of intestinal coccidiosis. During a study period of one decade, Isospora belli were identified in the stool samples of seven children with diarrhea. Diarrhea persisted for a little longer period in HIV-seropositive children compared to sero-negatives but the clinical picture did not differ significantly in either HIV infected or HIV uninfected individuals.

Parasites from swine faeces were examined for autofluorescence. Oocysts of Eimeria polita, E. scabra and Isospora suis, cysts of Balantidium coli and eggs of Oesophagostomum dentatum, Strongyloides ransomi and Trichuris suis (but not those of Ascaris suum) emitted light after excitation with UV light. I. suis oocyst counts in McMaster chambers utilising autofluorescence were compared to those from conventional bright field microscopy. Similarly, faecal smears containing I. suis were examined using the same techniques. Autofluorescence was superior to bright field microscopy in detecting oocysts after flotation and was highly significantly more sensitive when direct smears were examined.

Isospora belli, a coccidian parasite in humans, has been described as causing chronic diarrhea and acalculous cholecystitis in patients with the acquired immunodeficiency syndrome (AIDS). Diagnosis can be made at the tissue level in the epithelium of the small bowel and by fecal examination. Disseminated extraintestinal forms are uncommon. We studied 118 adult patients with AIDS and chronic diarrhea using stool analysis and endoscopy with duodenal biopsy specimen collection. These samples were processed by routine histology and transmission electron microscopy. Isosporosis was diagnosed in 8 cases. In 2 of them, unizoite tissue cysts were present in the lamina propria, with negative results in stool materials. The cysts were located within a large parasitophorous vacuole. There were no structural means of differentiating the species level of Isospora based on morphology using light or electron microscopy. We believe further work should be done to determine if unizoite tissue cysts are part of the cycle of I belli or of other species of Isospora that could be pathogenic in immunocompromised hosts.

Isospora suis and Eimeria are frequent coccidian parasites of pigs. The unsporulated oocysts of Eimeria species and of I. suis are difficult to differentiate. Therefore, a species-specific PCR was developed. PCR products were amplified from Eimeria polita, Eimeria porci, and Eimeria scabra using primers from the conserved 18S rRNA regions and were subsequently sequenced. Based on variable sequence regions, primers were constructed for the differentiation of the three Eimeria species and I. suis. Using a combination of PCRs detecting one or two species, all four coccidian species were detected (theoretical lower detection level: DNA content of 250 oocysts of each Eimeria species or 25 oocysts of Isospora in 1microl) and differentiated. The PCR-based differentiation of the above mentioned species provides a useful alternative to microscopy.

The aim of the present study was to use small-subunit (SSU)-rRNA sequences of Isospora belli to design specific primer pairs and a hybridization probe for the detection of Isospora belli in human samples by PCR and Southern blot hybridization. PCR amplification with the primer pairs produced correct DNA fragments with target DNA from samples of Isospora belli-infected patients and from cloned SSU-rRNA of Isospora belli. The nature of the PCR products was confirmed by Southern blot hybridization. No amplification was seen with template DNA extracted from other parasites. Although Isospora belli infections can be easily diagnosed using light microscopy, molecular-based techniques may prove useful as an additional diagnostic tool.

Objective: Fluorescent stains with Uvitex 2B or other fluorochromes are widely used today, especially for the diagnosis of microsporidian infections in human immunodeficiency virus (HIV)-infected patients. Our objective was to ascertain whether the fluorescent stain with Uvitex 2B is also able to detect Isospora belli in stool samples and duodenal/bile juice of HIV-infected patients., Design: Case study., Setting: University hospital of the University of Cologne, Germany., Patients: Two HIV-infected patients with chronic diarrhea who had intestinal infections with I. belli., Methods: Stool was concentrated by a modified water-ether sedimentation method, and duodenal/bile juice was concentrated by centrifugation. Wet-mount preparations were examined by phase-contrast and bright-field microscopy, and smears were stained with a modified acid-fast stain and a fluorescent stain with Uvitex 2B., Results: Using the fluorescent stain with Uvitex 2B, the oocysts of I. belli stained bright white/blue fluorescent and showed a structure similar to that of the oocysts in acidfast stains., Conclusions: Staining with Uvitex 2B is a suitable method for the diagnosis of I. belli infections. This technique can be used for the diagnosis of three important gastrointestinal parasites (viz, microsporidia, cryptosporidia, and I. belli) responsible for diarrhea in HIV-infected patients.