Virological efficacy and immunological recovery among Ethiopian HIV-1 infected adults and children

Abstract

Background: Introduction of antiretroviral therapy (ART) in sub-Saharan Africa was a hot debate due to many concerns about adherence, logistics and resistance. Currently, it has been significantly scaled up. However as the WHO clinico-immunological approaches for initiation and monitoring of ART in the region lacks viral load determination and drug resistance monitoring, HIV infected adults and children may be at risk for "unrecognized" virologic failure and the subsequent development of antiretroviral drug resistance. This study evaluates the virological efficacy and immunological recovery of HIV/AIDS patients under ART.

Methods: Consecutive HIV-1 infected adults (N = 100) and children (N = 100) who have been receiving ART for up to 6 years at Gondar University Hospital, Ethiopia were enrolled following the WHO protocol for assessment of acquired drug resistance. Magnitude of viral suppression, genotypic drug resistance mutations and patterns of CD4+ T cell recovery were determined using standard virological and immunological methods.

Results: Virological suppression (HIV RNA < 40 copies/ml) was observed in 82 and 87% of adults and children on a median time of 24 months on ART, respectively. Mutation K103N conferring resistance to non nucleoside reverse transcriptase inhibitors and thymidine analogue mutations (M41L, L210W) were found only in one adult and child patient, respectively. Median CD4+ T cell count has increased from baseline 124 to 266 (IQR: 203-306) and 345 (IQR: 17-1435) to 998 (IQR: 678-2205) cells/mm3 in adults and children respectively after 12 months of ART. Nevertheless, small but significant number of clinically asymptomatic adults (16%) and children (13%) had low level viraemia (HIV-1 RNA 41-1000 copies/ml).

Conclusions: Majority of both adults (82%) and children (87%) who received ART showed high viral suppression and immunological recovery. This indicates that despite limited resources in the setting virological efficacy can be sustained for a substantial length of time and also enhance immunological recovery irrespective of age. However, the presence of drug resistance mutations and low level viraemia among clinically asymptomatic patients highlights the need for virological monitoring.

Figure 1

CD4⁺ T cell count over a period of 48 months. Trend in CD4⁺ T cell recovery among HIV/AIDS adult patients over a period of 48 months on ART. The straight line in the graph is the trend line showing the increase of CD4⁺ T cells at a steady rate over 48 months on ART. The R-squared value is 0.9125 shows a good fit of the line to the data. The equation (Y = 31.35X + 153.65) on the graph is the regression analysis that extends a trend line in a chart beyond the actual data to predict future values.

Figure 2

Mean CD4⁺ T cell recovery in different strata during ART. The mean CD4⁺ T cell recovery of adult patients with low baseline CD4⁺ T cell strata (< 50 cells/mm³) and higher CD4⁺ T (200–349 cells/mm³⁾ at the initiation of ART over a period of 48 months on ART.