High prevalence of Microsporidium infection in HIV-infected patients.

Sixty-four patients infected with human immunodeficiency virus (HIV) participated in a study to determine opportunistic enteric pathogens and compare them with the patients' clinical status. The most frequently found pathogens were microsporidium (81.2%), Cryptosporidium parvum (20.3%), Candida albicans (12.5%) and Blastocystis hominis (10.9%). Less frequently found pathogens were Giardia intestinalis (6.2%), Cyclospora (4.7%), Opishorchis viverrini ova (3.1%), Strongyloides stercoralis larvae (3.1%) and hookworm ova (1.6%). The presence of enteric pathogens was not significantly associated with sex, length of HIV seropositivity and diarrheal symptoms. A high prevalence of microsporidium, based on microscopic examination, was found in Thai HIV-infected patients. This confirms the importance of microsporidium in HIV-infected/AIDS patients and the necessity for stool evaluation in all HIV-infected patients.

Early detection and identification of amphizoic amoebae from nasal exudates of a symptomatic case.

A man visited the Out Patient Department of the hospital for Tropical Diseases in February 2004 with low grade fever and severe headache for a week. He had the history of diving in a natural pond 2-3 days before the onset of the disease. A thick bloody mucous was observed from the nasal discharge. Fresh microscopic observation of the exudates in 0.85% sodium chloride revealed numerous active amoeba trophozoites. Two groups of the trophozoites were observed The first group was 10 micro sized amoeba with active directional movement by lobopodia and the second group was 15-30 micro sized amoeba with active multiprogressive movement by filopodia. Few flagellate forms were observed after exflagellation in distilled water and some polygonal cysts were also found. Giemsa' stain was used to differentiate the amoeba trophozoites from the leukocytes. It was concluded that this patient was infected by both Naegleria spp. and Acanthamoeba spp. This is the first report of double infection of free-living amoeba in a symptomatic and non-fatal patient.

Pathologic study of acute toxoplasmosis in experimental animals.

We studied the pathology of acute toxoplasmosis in experimental mice inoculated with RH strain tachyzoites of Toxoplasma gondii. All died from severe disseminated toxoplasmosis involving the liver, spleen and pancreas. Pathological features of acute toxoplasmosis in susceptible mice could be regarded as an excellent model for acute reactivation of Toxoplasma in the immunosuppressed host.

Rapid Wright's stain for the detection of imported Leishmania tropica.

Leishmania tropica (cutaneous leishmaniasis) can be detected easily, rapidly, and conveniently by the examination of a skin ulcer smear that is stained with a modified method of Wright staining of blood (ie that used for routine hematological examinations).

Necropsy in HIV-infected patients.

Human immunodeficiency virus (HIV)infection is usually followed by opportunistic infections, especially in the full-blown acquired immunodeficiency syndrome (AIDS). This study details the histopathological changes of different organs in relation to HIV infection, with particular emphasis on the opportunistic infections. Various organs from seventeen HIV-infected patients were collected by necropsy and analyzed for histopathological changes. The major histopathological changes included cytomegalovirus infection, cryptococcosis, penicilliosis, bacterial pneumonia, cryptosporidiosis, pneumocystosis, candidiasis, tuberculosis, granulomatosis of unknown etiology, early cirrhosis and chronic active hepatitis. General organ changes from seventeen cases of HIV-infected patients were described and discussed.