Seroprevalence of IgG Anti-Toxoplasma Antibodies in HIV positve adult Zambians attending the Antiretroviral -therapy clinic at the University Teaching Hospital
Toxoplasma gondii is an intracellular protozoan parasite, and causes zoonotic infection. It is estimated that more than one billion people world wide are affected by the parasite. Toxoplasma encephalitis has become one of the most frequent opportunistic infection in HIV infected patients. The diagnosis of toxoplasmosis is complicated and involves the use of multiple serological and radiological investigations in combination with the clinical signs and symptoms of the patient. Toxoplasmosis thus poses a serious diagnostic challenge even for health facilities with advanced diagnostic equipment. In resource-poor settings such as Zambia the diagnosis of toxoplasmosis is based mostly on clinical presentation only requiring the clinician to have a high index of suspicion for toxoplasmosis. Despite the importance of this condition, the seroprevalence of toxoplasmosis among HIV positive Zambians had not previously been fully investigated. Objective is to determine the seroprevalence and factors associated with IgG anti-toxoplasma antibodies among HIV positive adult Zambians attending the ART clinic at the UTH. A Prospective cross-sectional hospital-based study was carried out on 156 HIV positive adult Zambians (18 years and above) attending ART clinic at UTH. 3mls of sera from 156 HIV positive persons attending the ART clinic at UTH were analysed for the presence of IgG anti-toxop/asma antibodies using commercial ELISA assays (Genesis Diagnostic Toxoplasma IgG Enzyme Immunoassay, Cambridgeshire, UK and Biotec Toxoplasma IgG Enzyme Immunoassay, Sulffolk, U.K). A questionnaire was used to collect data on sex, age, HIV status, CD4 count, residential area, education level, occupation and work, food habits and socioeconomic variables. The prevalence of IgG anti-toxoplasma antibodies was 17.9%. Females constituted 55% of the population. The chi-square test showed a statistically significant association between IgG anti-toxoplasma serostatus and blood transfusion (p= 0.0152). This result was upheld with multiple logistic regression (OR=0.307, confidence interval 0.114-0.826). There was also a statistically significant association between age and IgG anti-toxoplasma seropositivity (p=0.0374). However, this result did not hold under multiple logistic regression. The seroprevalence of IgG anti-toxoplasma antibodies among Adult HIV positive patients at UTH is much higher than previously reported. A large proportion of HIV positive patients attending the ART clinic at UTH and are at risk of toxoplasmosis may not be receiving co-trimoxazole prophylaxis. There was a significant association between blood transfusion and IgG serostatus shown in this study. This suggests that screening of donor blood for toxoplasmosis may be important.
Opportunistic Infection in HIV infected persons-Zambia