HIV and intestinal parasite co-infections among a Chinese population: an immunological profile.

BACKGROUND: Parasite infections often result in a switch of the human body's predominant immune reaction from T-helper 1 (Th1)-type to Th2-type. Hence, parasite infections are widely expected to accelerate the progression of human immunodeficiency virus (HIV) infections to acquired immunodeficiency syndrome (AIDS). In the People's Republic of China, both parasitic diseases and AIDS are epidemic in certain rural areas, and co-infections are relatively common. However, no population-based studies have yet investigated the frequency of HIV and parasite co-infections, and its effects on immune responses. We studied (1) the immune status of an HIV-infected population, and (2) the effect of co-infection of HIV and intestinal parasites on selected parameters of the human immune system. METHODS: A total of 309 HIV-infected individuals were recruited and compared to an age-matched and sex-matched control group of 315 local HIV-negative individuals. Questionnaires were administered to all participants to obtain information on sociodemographic characteristics, sanitation habits, family income, and recent clinical manifestations. Two consecutive stool samples and 10 ml samples of venous blood were also collected from each individual for the diagnosis of parasite infections and quantitative measurements of selected cytokines and CD4+ T-lymphocytes, respectively. RESULTS: During the study period, 79 HIV-infected individuals were not under highly active antiretroviral therapy (HAART) and were thus included in our analysis; the prevalence of intestinal helminth infections was 6.3% and that of protozoa was 22.8%. The most common protozoan infections were Blastocystis hominis (B. hominis) (13.9%) and Cryptosporidium spp. (10.1%). The prevalence of Cryptosporidium spp. in HIV-infected individuals was significantly higher than that in HIV negative individuals (P < 0.05). Compared to the non-co-infected population, no significant difference was found for any of the measured immunological indicators (P > 0.05). However, the following trends were observed: IFN-γ levels were lower, but the IL-4 level was higher, in the population co-infected with HIV and helminths. In the population co-infected with HIV and B. hominis, the IL-2 level was higher. The population co-infected with HIV and Cryptosporidium spp. had markedly lower CD4+ T-lymphocyte counts. CONCLUSION: According to the immunologic profile, co-infection with helminths is disadvantageous to HIV-infected individuals. It was associated with a shift in the Th1/Th2 balance in the same direction as that caused by the virus itself, which might indicate an acceleration of the progress from an HIV infection to AIDS. Co-infection with Cryptosporidium spp. was not associated with a significant change in immune factors but co-infection with Cryptosporidium spp. was associated with a reduced level of CD4 + T-lymphocytes, confirming the opportunistic nature of such infections. Co-infection with B. hominis, on the other hand, was associated with an antagonistic shift in the immunological profile compared to an HIV infection.

Value of 3.0 T diffusion-weighted imaging in discriminating thecoma and fibrothecoma from other adnexal solid masses.

BACKGROUND: To investigate the value of diffusion-weighted imaging (DWI) at 3.0 T (3T), and especially the apparent diffusion coefficient (ADC), in discriminating ovarian thecoma from other adnexal solid masses. METHODS: Eighteen thecomas or fibrothecomas, 14 ligamentous leiomyomas, and 24 other ovarian solid tumors underwent prospective DWI magnetic resonance imaging (MRI) in addition to routine MRI on a 3T MRI machine. The baseline characteristics, components, and conventional MRI and DWI-MRI signals for the thecomas were recorded. The ADC values (ADCs) were measured for each group and compared. RESULTS: The thecomas often appeared as homogeneous isointensity (17/18) on T1-weighted images (T1WI; 11/18) or T2WI (11/18) on DWI-MRI, with minor (9/18) or mild (6/18) enhancement. The mean ADC value for thecoma (1.20 ± 0.45 × 10-3 mm2/s) was almost equal to that of the other solid ovarian masses (1.26 ± 0.51 × 10-3 mm2/s), but lower than that for leiomyoma (1.48 ± 0.42 × 10-3 mm2/s), although not significantly so. There was a significant difference (p = 0.043) in the ADCs of the benign ovarian solid masses (1.16 ± 0.47 × 10-3 mm2/s) and leiomyomas (1.48 ± 0.42 × 10-3 mm2/s). CONCLUSIONS: There is no significant difference in ADC between thecoma and other adnexal solid masses, but the ADCs of thecomas are lower than those of leiomyomas.

Co-infection of HIV and intestinal parasites in rural area of China.

BACKGROUND: Intestinal parasite infections (IPIs) are among the most significant causes of illness and disease of socially and economically disadvantaged populations in developing countries, including rural areas of the People's Republic of China. With the spread of the human immunodeficiency virus (HIV) among rural Chinese populations, there is ample scope for co-infections and there have been increasing fears about their effects. However, hardly any relevant epidemiological studies have been carried out in the country. The aim of the present survey was to assess the IPI infection status among a representative sample of HIV-positive Chinese in rural Anhui province, and compare the findings with those from a cohort of non-infected individuals. METHODS: A case control study was carried out in a rural village of Fuyang, Anhui province, China. Stool samples of all participants were examined for the presence of intestinal parasites. Blood examination was performed for the HIV infection detection and anemia test. A questionnaire was administered to all study participants. RESULTS: A total of 302 HIV positive and 303 HIV negative individuals provided one stool sample for examination. The overall IPI prevalence of intestinal helminth infections among HIV positives was 4.3% (13/302) while it was 5.6% (17/303) among HIV negatives, a non-significant difference. The prevalence of protozoa infections among HIV positives was 23.2% while the rate was 25.8% among HIV negatives. The species-specific prevalences among HIV positives were as follows: 3.6% for hookworm, 0.7% for Trichuris trichiura, zero for Ascaris lumbricoides, 0.3% for Clonorchis sinensis, 1.3% for Giardia intestinalis, 16.2% for Blastocystis hominis, 1.7% for Entamoeba spp. and 8.3% for Cryptosporidium spp.. Cryptosporidium spp. infections were significantly more prevalent among HIV positives (8.3%) compared to the HIV negative group (3.0%; P < 0.05). Among people infected with HIV, Cryptosporidium spp. was significantly more prevalent among males (12.6%) than females (4.4%; P < 0.05). According to multivariate logistic regression, the factors significantly associated with parasite infections of the people who were HIV positive included sex (male: OR = 6.70, 95% CI: 2.030, 22.114), younger age (less than 42 years old: OR = 4.148, 95% CI: 1.348, 12.761), and poor personal hygiene habits (OR = 0.324, 95% CI: 0.105, 0.994). CONCLUSIONS: HIV positive individuals are more susceptible to co-infections with Cryptosporidium spp. than HIV negative people, particularly younger males with poor personal hygiene habits, indicating a need for targeted hygiene promotion, IPI surveillance and treatment.

[The current status of schistosomiasis epidemics in China].

OBJECTIVE: To analyze the change of tendency on schistosomiasis epidemics in China in the last 5 years. METHODS: Data on schistosomiasis epidemics in the history and particularly in the last 5 years were collected. Tendency and the re-emerging status after 1998 were analyzed. RESULTS: Data in 2003 showed that in 42%, 40% and 53% of the provinces, counties and townships with epidemics, the transmission of the disease has been interrupted or controlled. The number of estimated patients of schistosomiasis and areas with snails were also reduced by 92.74% and 73.56%, in 2003. The annual estimated number of chronic cases was around 800 000 and 31 321.5 hectare of snail infested areas were newly identified in recent 5 years. Among 20 national villages under longitudinal surveillance, 30%, 70% and 35% of the villages were presented a tendency of increase in the rates of human infection, bovine infection and Oncomelania snails infection, respectively. A total of 38 counties from 7 provinces have re-emerged in schistosomiasis transmission after those counties having reached criteria of transmission under control or interrupted. In 6 non-endemic counties, snails were presented, and 16 marshlands in Xan river were found with appearance of acute cases of schistosomiasis. More snail infested areas were found in Shanghai, Zhejiang, and Fujian. Both snail infested areas and newly infected cases were occurred in urban areas along the Yangtze River. CONCLUSION: The tendency of increase was presented in focal areas along the Yangtze River, due to changes of environmental, ecological, societal and economic status, as well as on the forces of control.

[Establishment of minimum medical geographic information systems database in China].

OBJECTIVE: To establish a minimum medical geographic information systems (GIS) database as a spatial decision supporting system (SDSS), and to use the database into public health practice in China. METHODS: Spatial data collected from different sources were standardized as decimal degree format, including: (1) satellite images covering areas of China; (2) digital maps of China in vector files; (3) diseases database and relevant models. RESULTS: Necessary satellite images for the database have been collected from NOAA AVHRR, Landsat TM, etc., including the normalized difference vegetation index (NDVI) images from AVHRR, earth surface temperature images from AVHRR, GTOPO30 DEM images from USGS and landuse images from USGS. The digital vector files for GIS analysis were collected including political (county, provinces, country) boundaries file, environmental (drainage, land cover, soil type) vector file, population data and climate data; Data on diseases mainly generated from survey or case reporting. Relevant models on transmission of Schistosoma japonicum and Plasmodium vivax, and models of Oncomelania hupensis and Anophores sinansis were developed, and the relevant environmental factors related to incidence of cancers were mapped, to test and verify those database. CONCLUSION: The database unified the data from different sources for users. Minimum medical data included in the database could be used in the practice of public health. It is expected that this database be used in a wider range.