Cryptosporidiosis ; diagnosis ; etiology ; Humans ; Prognosis

Cryptosporidium, a coccidian parasite first described by Tyzzer (1907) from a laboratory mouse, has become an important human enteric pathogen causing overwhelming diarrhea especially in immunocompromised patients such as AIDS. This parasite has been reported from over 20 countries and is recognized as a cosmopolitan species. In Korea, however, there has been no report on human as well as animal cryptosporidiosis. This study was performed so as to verify the presence of Cryptosporidium in Korea by activating the parasite from laboratory mice by immunosuppression. Total 65 conventionally-bred ICR mice including a control (5 mice) and 3 experimental groups (20 each) were used for this study. Group I was immunosuppressed with prednisolone injection (1 mg IM, every other day) for 7 weeks. Group II (prednisolone injection and tetracycline administration) and Group III (prednisolone injection and trimethoprim-sulfamethoxazole administration) were prepared to observe the effect of antibacterial agents on the activation of cryptosporidiosis. In fecal examinations of mice Cryptosporidium oocysts (4-6 microns in size) were detected from 1 week after the start of immunosuppression and the mice began to die. In H-E stained tissue sections of the lower jejunum, numerous very small (2-4 microns), dense, ovoid or spherical, slightly basophilic bodies were seen attached on the free border of mucosal epithelial cells. In scanning and transmission electron microscopic observations, these organisms were identified as various developmental stages of Cryptosporidium. The species is considered to be C. parvum.(ABSTRACT TRUNCATED AT 250 WORDS)
Cryptosporidiosis-etiology ; Cryptosporidiosis-immunology ; Cryptosporidium-growth-and-development ; English-Abstract ; Immune-Tolerance ; Intestinal-Diseases,-Parasitic-etiology ; Intestinal-Diseases,-Parasitic-immunology ; Mice- ; Mice,-Inbred-ICR ; *Cryptosporidiosis-parasitology ; *Cryptosporidium-pathogenicity ; *Immunosuppression- ; *Intestinal-Diseases,-Parasitic-parasitology

OBJECTIVETo investigate the infection of Cryptosporidium and its epidemiological characteristics in AIDS patients of Southern China.

METHODSStool samples colleted from AIDS confirmed patients. The samples were detected for oocyst of Cryptosporidium by acid fast bacteria stain and indirect fluorescent antibody stain respectively, CD4 count was detected by Flow Cytometry.

RESULTS212 samples of fresh stool obtained from the AIDS patients who live in Guangdong and Yunnan province. The total infection rate of Cryptosporidium in AIDS patients was 4.25% (9/212), the infectious rate of oocyst in the group of 50- 59-years-old was significantly higher than those in 30-39 (P < 0.01); the infectious rate of oocyst in patients with antiretroviral therapy (ART) was also significantly lower (P = 0.0000); we found the patients coinfected with Cryptosporidium with CD4 count all below 100 cells/microl. However, there were no any difference between the infectious rate to the patient's gender, areas and stool shape.

CONCLUSIONAIDS patients infected by Cryptosporidium are not rare in southern China, and the infectious rate was lower than western country. Patients received ART could decrease the infectious rate of Cryptosporidium, Cryptosporidium always happen in patient whose CD4 count was very low (< 100 cells/microl).

AIDS-Related Opportunistic Infections ; parasitology ; Acquired Immunodeficiency Syndrome ; complications ; parasitology ; Animals ; Antigens, Protozoan ; CD4 Lymphocyte Count ; China ; Cryptosporidiosis ; diagnosis ; etiology ; immunology ; parasitology ; Cryptosporidium ; chemistry ; isolation & purification ; Feces ; parasitology ; Flow Cytometry ; HIV Infections ; parasitology ; Humans ; Oocysts ; Staining and Labeling