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Intestinal microsporidiosis is an opportunistic parasitological infection affecting mainly immunocompromised patients, particularly those infected with HIV.The purpose of this study was to analyse the epidemiological and clinical characteristics of intestinal microsporidiosis and the treatments available for it.This retrospective study examined records collected over a 13-year period (from January 1995 through December 2007). It included 572 immunocompromised patients (279 HIV-infected patients and 293 without HIV infection) with symptoms suggesting intestinal microsporidiosis. All were tested systematically for microsporidia spores by modified (Weber's) Trichrome staining.Fourteen patients (10 men, 4 women) were diagnosed with intestinal microsporidiosis, for a prevalence of 2.4% overall, 3.6% in HIV-infected patients and 1.4% in those without HIV infection. Intestinal microsporidiosis affected 10 HIV-infected patients, 70% of whom had a CD4 count100 cells/mm3. Their mean age was 30+/-15 years (range: 15 months to 48 years). The average age of HIV-infected patients (36 years) was significantly higher than of those without HIV infection (15 years). Thirteen patients had symptoms, most frequently diarrhea (11 cases), sometimes associated with dehydration (5 cases). Eight patients (57%) received only symptomatic treatment, and 4 (28.6%) received albendazole. No treatment was recommended in 2 cases (14.3%). Clinical course was marked by improvement in 6 cases, death in 5, and persistence of asymptomatic carriage in one. Two patients were lost to follow-up.Intestinal microsporidiosis is a parasitological disease that mainly affects AIDS patients with CD4 counts100 cells/mm3. Its diagnosis requires special techniques. Its symptomatology is dominated by chronic diarrhea that can cause dehydration. Effective treatment requires identification of the species.

Intestinal microsporidiosis is recognised as an important cause of opportunistic parasitosis in immunocompromised patients, especially HIV-infected patients. Enterocytozoon bieneusi is the common causal agent. The diagnosis of intestinal microsporidiosis has usually based on microscopic detection of the spores of microsporidia species in stool samples, requires additional staining techniques as Modified Weber's trichrome stain. However, the detection of the spores can be difficult and species determination, which is important for defining the appropriate treatment, is impossible. Polymerase chain reaction (PCR)-based methods have been successfully used for detection of microsporidian infections. They are more sensitive and are able to identify microsporidia species. The purpose of this study is to identify E. bieneusi to adapt treatment and assess the true prevalence of the intestinal microsporidiosis due to this species in compromised patients in Tunisia.One hundred and eighteen stools from immunocompromised patients, with a symptomatology in favour of the intestinal microsporidiosis, were analysed using light microscopy after staining with Modified Weber's trichrome stain and PCR.Only four were positive by Modified Weber's trichrome stain whereas eleven stools were positive by PCR, giving a prevalence of 20% in HIV-infected patients and 5,35% in human immunodeficiency virus-negative patients.This study confirms the usefulness of PCR in the diagnosis of the intestinal microsporidiosis due to E. bieneusi. Indeed, PCR has greater sensitivity than Modified Weber's trichrome stain and can identify the species of microsporidia in order to adapt the treatment.

Intestinal microsporidiosis are among the most frequent opportunistic diseases in immunocompromised subjects. This study aimed to evaluate the contribution of PCR for a better detection and species identification of microsporidia in stool specimens of HIV-infected patients.Stool samples obtained from 119 HIV-infected Tunisian subjects were screened for intestinal microsporidiosis by light microscopy using Weber's modified Trichrome stain and by a PCR method using universal primers V1/PMP2 which amplified a common fragment of the small subunit rRNA gene of microsporidia. The obtained PCR products were then sequenced using an ABI PRISM 377 DNA sequencer.The results showed a better sensitivity of PCR in the detection of microsporidia with an infection rate of 14.3% significantly higher than that of 6.7% obtained by light microscopy (p=0.03). As previously described, intestinal microsporidiosis was associated with low CD4 cell counts; 23.9% infection rate in patients having CD4 cell count under 200/mm(3) against 5.6% in patients with higher CD4 cell count (p=0.008). The sequencing of 15 out of the 17 positive PCR products has confirmed in all cases the species identified based on the PCR fragment size i.e., 250pb for Enterocytozoon bieneusi (seven cases) and about 270pb for Encephalitozoon intestinalis (nine cases); one case revealed a double infection.PCR proved to be more effective than classical Trichrome stain for the diagnosis of intestinal microsporidiosis. Moreover, the ability of PCR to identify the species involved could also be useful for cases management.

Incidences of opportunistic infections of the epididymus and the testicule have already been reported in patients suffering from AIDS for over 10 years. Here we have reported the first description of microsporadic orchiepididymitis diagnosed at the university hospital (CHU) of Nice in 2005. We look at the epidemiology, the physiology and the treatment of this extremely rare infection.

Determine the prevalence of intestinal parasitosis between January 1, 1997 and December 31, 1999 in the microbiology laboratory of the Fort de France University Hospital.Retrospective study of the results of 4684 parasitological examinations of stools performed in 2704 patients between January 1, 1997 and December 31, 1999 in this laboratory.This survey showed the high prevalence of anguillulosis, found in 51.69% of infested patients and in 4.56% of the population studied, the ever high prevalence of non or scarcely pathogenic amoebas (Endolimax nanus, Dientamoeba fragilis, Entamoeba coli) found in 27.19% of infested patients and 1.88% of the population studied, together with that of hookworms (12.80% of infested patients and 1.13% of the population), and the persistence of lambliasis. This study also revealed the presence of cryptosporidies (7 cases) and microsporidies (4 cases) in the patients infected by the human immunodeficiency virus.These results confirm the trend of the past twenty Years and the results of surveys initiated by the national statistics board (INSERM) in 1978, 1988 and 1995-1995, with the regression of bilharziosis and the persistence of anguillulosis and hookworms.The improvement in living conditions and hygiene, the combined efforts of the health care workers and Authorities in Martinique over the past 30 Years in the fight against parasites have led to a great reduction in the prevalence of classical intestinal parasitosis. However, new parasites associated with HIV infection have appeared.

The immunodepression, related or not to AIDS, induces the emergence of opportunistic parasitosis and mycosis. Our objective is to analyze these pathogenic agents, their clinical expression and gravity in immunocompromised individuals. Our retrospective 9 years study reported parasitic and fungic infections complicating immunodepression. Among 31 HIV infected patients, we diagnosed the following parasitosis: Cryptosporidium (7 cases), Isospora belli (2 cases) and Enterocytozoon bieneusi (1 case). Pulmonary pneumocystosis was diagnosed in 6 cases, cerebral toxoplasmosis in 6 cases and meningo-cerebral cryptococcosis in 1 case. The systemic candidasis was diagnosed in 13 leukaemic patients. The intestinal anguilluliasis was found in 5 patients treated with corticoïds for long periods. A case of Kala azar was observed in a 83 years man treated with corticoïds. A disseminated aspergillosis occurred in a child with a Chediack Higashi syndrome. A gingivo-labial fusariosis was diagnosed in a leukaemic patient. This emergency of the new parasitic and fungal agents requires a better understanding of these affections in order to improve their early diagnosis and treatments.

OPPORTUNISTIC PARASITES: Microsporidia are primitive eukaryotic parasites widespread in a large range of animal species. These opportunistic parasites can cause infections in humans, mainly in immunocompromised patients.Four microsporidian species are important in human pathology, Enterocytozoon bieneusi, Encephalitozoon intestinalis, Encephalitozoon cuniculi and Encephalitozoon hellem.A difficult task, laboratory diagnosis is based on direct microscope visualization of the parasite. Special stains not used in routine practice are required for identifying spores.Species differentiation, achieved with the polymerase chain reaction technique, is necessary to select the appropriate treatment. Treatment of the most common microsporidiosis (caused by Enterocytozoon bieneusi) with fumagillin is currently under assessment in an ANRS clinical trial.

Cryptosporidium and Microsporidian play an important part in the diarrhoeic pathology of the immunocompromised patients. The study of 35 cases of cryptosporidiosis and 4 cases of intestinal microsporidiosis diagnosed in the parasitology laboratory of Rabta hospital of Tunis shows that cryptosporidiosis prevalence is 17.24% for AIDS patients, 3.45% for immunocompromised patients VIH (-), and microsporidiosis prevalence is 5.7% for patients with acquired immunodeficiency syndrome. Common points for these two parasitosis are: Clinical syndromes dominated by an acute diarrhea A diagnosis based on specific techniques showing the significance of the clinical orientation. Lack of an effective specific therapy.

An HIV-positive patient developed disseminated Enterocytozoon bieneusi infection. The parasite was identified in stool, duodenal biopsy, nasal discharge, and sputum specimens using transmission electron microscopy. Albendazole therapy failed to improve the symptoms or eradicate the parasite. The patient survived for nine months after the diagnosis of E. bieneusi infection.

Diarrhea due to infection with Microsporidium (M) or Cryptosporidium (C) raises significant therapeutic challenges in HIV-infected patients. The usefulness of protease inhibitor therapy was evaluated in 20 HIV-positive patients with positive tests for M and/or C. There were 17 men and three women with a mean age of 42.5 years (range, 26-64 years). Two patients had category B disease and 18 category C disease according to the 1993 CDC classification scheme (CD4 count before therapy, 72/mm3; mean viral burden, 4.6 log). Seventeen patients had chronic diarrhea (due to M in 12 cases and to C in five), and the remaining three patients were asymptomatic M carriers. Clinical symptoms resolved after addition to the antiretroviral regimen of indinavir (n = 17) or saquinavir (n = 3). Mean weight gain was 10.5 kg. Karnofsky's index improved. Twelve patients, including one of the three who were asymptomatic at baseline, had negative follow-up stool cultures. The mean CD4 count increase was 125/mm3, and the mean viral burden decrease was 1.285 log. These data suggest that protease inhibitors may be capable of eradicating M and/or C infection refractory to other treatments. The reason for this effect may involve partial restoration of immune function due to inhibition of HIV replication.

The diagnosis of microsporidiosis by staining stools is known to be fast and cheap. To obtain a specific and sensitive result, two colorimetric methods must be used: staining by the fluorochrome Uvitex 2 B (VAN GOOL) and trichrome. Among the four staining methods of trichrome currently studied, the WEBER coloration could be considered as the most efficient. The density of microsporidia spores could be semi-quantitatively evaluated, because their distribution is homogeneous.

We studied 66 cases of intestinal mycosis and parasitosis in patients infected with the human immunodeficiency virus with chronic diarrhea. All subjects were from the Yaounde urban area and were followed between February and December 1996. They were recruited from 3 hospitals in the center of Yaounde and were aged between 2 and 52 years. There was weight loss in 80.3% and severe dehydration in 72.3% of cases. Feces consisted mostly of watery stools similar to those of cholera patients (50% of cases) and loose stools (43.9% of cases). Parasitic agents were detected in 31.8% and fungal agents in 80.5% of cases. The opportunistic Protozoans detected included Cryptosporidium parvum (15.8%), microsporidia (8.8%) and Isospora belli (3.5%). Six cases of helminthiasis were also identified. Candida albicans was the most common opportunistic mycosis agent (39.1%). Other fungal species detected included Geotrichum candidum, Candida pseudotropicalis and Trichosporon sp. but all of these were less common.

A study was conducted between 1993 and 1996 in Bamako to determine the rate of occurrence of microsporidia in 88 patients. Most (80%) had chronic diarrhea associated with weight loss and 87.5% were HIV-positive. Intestinal microsporidia were detected in 32% of the patients infected with HIV-1, HIV-2, or coinfected with both strains. Microsporidiosis was also diagnosed in three of the eleven HIV-negative individuals (27%). Microsporidiosis was confirmed by electron microscopy in 6 HIV-positive patients and 1 HIV-negative individual. Enterocytozoon bieneusi was detected in each case. These results suggest that microsporidia are common pathogens in HIV-positive patients in Bamako. Cases of microsporidiosis have been reported for the first time in HIV-2-infected patients. The proportion of women microsporidiosis patients is higher in Mali than in industrialized countries. The presence of microsporidia in HIV-negative patients suggests that these parasites may be an underestimated cause of enteritis in developing countries.

Immunocompromised patients, notably those with cell mediated immunity deficiency, are at risk for severe and life-threatening parasitic infections. Severity and frequency of Pneumocystis carinii pneumonia have led to systematically initiate prophylaxis for high-risk patients such as patients with HIV infection, hemopathy or renal transplants. Cotrimoxazole has shown the best efficacy both in primary and secondary prophylaxis. Side effects, notably skin rash, constitute the major limiting factor of cotrimoxazole therapy. However, its efficacy in preventing cerebral toxoplasmosis and to a lesser extent bacterial infections, makes cotrimoxazole the drug of choice for HIV-positive patients in this direction. Aerosolized pentamidine is probably the best alternative considering its similar results in primary prophylaxis for patients with a CD4 countor = 100/mm3. Dapsone, associated with pyrimethamine for toxoplasmosis prevention, and atovaquone represent other possible alternatives. Such a prevention is absolutely necessary for HIV patients with a previous history of pneumocystosis or with less than 200 CD4/mm3. Moreover, children with SCID or acute leukemia as well as patients with renal or heart-lung transplantation would benefit from pneumocystosis prophylaxis. The frequency of relapses of visceral leishmaniasis also justifies a secondary prophylaxis. Because of its efficacy on P. carinii, intravenous pentamidine could be considered the drug of choice. However preliminary studies have indicated the value of liposomal amphotericin B (1 mg/kg twice a month) in this setting. Finally, cryptosporidiosis and microsporidiosis would benefit from secondary prophylaxis. However, since first line therapy is not well established, further studies are needed to precisely determine which drug could be of value.

Detection of microsporidia belongs to the usual coprologic and urine detection of parasites from HIV seropositive patients. To improve the identification of microsporidial spores, several stains have been used. Trichrome Blue stain has been evaluated in this study. We first compared Trichrome Blue stain to Weber's trichrome for the detection of microsporidia in smears of stools received from HIV seropositive patients. No difference of sensibility has been demonstrated between the two stains, and Uvitex 2B used on the same samples has confirmed these results. Then, Trichrome Blue stain has been used for the detection of microsporidial spores in other specimens (40 samples of nasal mucus, conjonctival samples, duodenal biopsy and urine), also Giemsa and Uvitex 2B. The advantage of Trichrome Blue stain is its ready-to-use presentation, and faster realisation at higher temperature. Trichrome Blue stain is interesting as a confirmation technique or for laboratories which do not have fluorescent microscopy equipment.

To determine the epidemiologic, clinical and aetiologic features of chronic diarrhoea in patients with human immunodeficiency virus (HIV) infection.Between January 1992 and April 1993, all HIV positive patients with chronic diarrhoea were enrolled in a prospective study. There were 46 patients in the study group including 33 (22 homosexuals) in stage C according to the 1993 Centers for Disease Control classification.Thirty-four pathogenic agents were isolated in 26 of the patients (57%). Enterocytozoon bieneusi was the most frequently found pathogen (11 patients, 24%) followed by Cryptosporidium sp (8 patients). Enterocytozoon bieneusi was found in association with other pathogens in 7 patients. All patients with microsporidiosis were in stage C (p = 0.04) and had a longer duration of diarrhoea (19.6 vs 9.8 weeks, p = 0.03), greater weight loss (9.6 vs 2.1 kg, p = 0.0003) and a lower Karnofsky index (48% vs 67%, p = 0.01). Prophylaxy with dapsone or pyrimethamine during the 3 months prior to inclusion had been more frequent (p = 0.04 and p = 0.05 respectively) in patients without microsporidiosis.Microsporidiosis should be suspected as a probable cause of chronic diarrhoea in HIV positive patients with a CD4 count100/mm3. Multiple infections may be a factor leading to treatment failure. Microsporidiosis seems to be linked to homosexual intercourse.

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Microsporidiosis is a recently identified opportunistic infection in patients with AIDS. Microsporidie usually induce chronic diarrhoeas, cachexia, and cholangitis. Disseminated infection with pulmonary or renal involvement and sinusitis has also been described. Rarely, conjunctivitis can occur. Diagnosis now relies on direct identification of microsporidial spores in faeces. Treatment remains essentially symptomatic, although cure can be obtained in some cases.

Microsporidia are worldwide ubiquitous intracellular protozoan parasites infecting most major groups of the animal kingdom. In humans, microsporidiosis has recently emerged as a significant cause of morbidity in immunocompromised patients, and particularly in patients with acquired immunodeficiency syndrome (AIDS). Parasites of the genus Encephalitozoon cause keratoconjunctivitis and disseminated infections. In 15 to 30% of patients with advanced stage AIDS, Enterocytozoon bieneusi is the causative agent of major chronic diarrhoea. Clinical manifestations include numerous (2 to 8) and abundant, irregular liquid or semi-liquid stools without evidence of intestinal haemorrhage. Impaired absorption is aggravated by food intake causing the patients to restrain from eating and subsequent weight loss is progressive and irreversible. The diarrhoea becomes permanent and leads to dehydration ad malnutrition. Spontaneous remissions have been observed but are always of short duration. Microsporidiosis has also been found in ocular localizations in patients with AIDS; these keratopathies may be due to Encephalitozoon cuniculi, the only known species in mammals but E. hellem, a morphologically identical but antigenically different species has been identified. Other visceral localizations have been observed. Diagnosis of microsporidiosis relies on the demonstration of spores and/or intracellular parasites in stools, urine or tissue biopsies. The responsible agent can generally be identified by light microscopy, but differentiation between species still requires electron microscopy. New light and fluorescent microscopic techniques have been proposed for easier recognition of spores in various pathological samples. Immunodiagnostic techniques are limited due to the lack of correlation between antibodies detection and clinical manifestations. Although the parasite can be identified and although its cycle has been carefully studied, no prophylactic action can be taken because the mode of transmission remains largely unknown. Many treatment protocols have been tried but none have been found to be effective. Very little pharmacological data has been accumulated. Microsporidiosis is, and will remain, a major opportunistic infectious disease causing uncontrollable debilitating malnutrition in AIDS patients unless an effective treatment can be found, a major challenge for medical science.

Microsporidia were infrequent in man until 1985. A new species, Enterocytozoon bieneusi, responsible for diarrhea, was described in AIDS patients in 1985. Little is known about the parasite; its diagnosis is difficult, and its incidence certainly underestimated. This work summarizes current knowledge on microsporidia (parasitology, clinical features, diagnosis and drug therapy).

The cytologic findings of duodenal smears in diarrheic HIV-positive patients were compared with results of histologic and ultrastructural studies. This study included 50 diarrheic patients undergoing upper gastrointestinal endoscopy. Duodenal biopsies were taken with touch preparations. Smears were stained with Giemsa and then with Ziehl-Neelsen or the PAS method. The biopsy specimens were then processed in a standard fashion for histologic and electron microscopy examination. Cytologic findings included 8 cases of intestinal microsporidiosis, 4 cases of cryptosporidiosis, and 3 cases of atypical mycobacteriosis. Histologic and ultrastructural studies confirmed these diagnoses and showed 8 cases of CMV enteritis, of which 4 were associated with other enteric pathogens. Duodenal cytology complements endoscopic biopsy in the work-up of diarrhea in AIDS patients and may provide a rapid diagnosis especially in the case of intestinal protozoonosis or atypical intestinal mycobacteriosis.

Light and electron microscopy studies of digestive tract biopsy specimens from AIDS patients are very useful for the detection of opportunistic pathogens which may be located in: the lumen (bacteria, Candida albicans, Giardia lamblia), enterocyte brush border (Cryptosporidium sp), enterocyte cytoplasm (Enterocytozoon bieneusi), enterocyte nuclei (cytomegalovirus), or cytoplasm of lamina propria macrophages (Mycobacterium avium intracellulare). These studies may also be useful to detect combinations of morbid conditions and to evaluate the effectiveness (if any) of therapeutic agents.

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