Determining eligibility for antiretroviral therapy in resource-limited settings using total lymphocyte counts, hemoglobin and body mass index.

BACKGROUND

CD4+ T lymphocyte (CD4) cell count testing is the standard method for determining eligibility for antiretroviral therapy (ART), but is not widely available in sub-Saharan Africa. Total lymphocyte counts (TLCs) have not proven sufficiently accurate in identifying subjects with low CD4 counts. We developed clinical algorithms using TLCs, hemoglobin (Hb), and body mass index (BMI) to identify patients who require ART.

METHODS

We conducted a cross-sectional study of HIV-infected adults in Uganda, who presented for assessment for ART-eligibility with WHO clinical stages I, II or III. Two by two tables were constructed to examine TLC thresholds, which maximized sensitivity for CD4 cell counts <or= 200 cells microL, while minimizing the number offered ART with counts > 350 cells microL. Hb and BMI values were then examined to try to improve model performance.

RESULTS

1787 subjects were available for analysis. Median CD4 cell counts and TLCs, were 239 cells/microL and 1830 cells/microL, respectively. Offering ART to all subjects with a TLCs <or= 2250 cells/microL produced a sensitivity of 0.88 and a false positive ratio of 0.21. Algorithms that treated all patients with a TLC <2000 cells/microL, excluded all patients with a TLC >3000 cells/microL, and used Hb and/or BMI values to determine eligibility for those with TLC values between 2000 and 3000 cells/microL, marginally improved accuracy.

CONCLUSION

TLCs appear useful in predicting who would be eligible for ART based on CD4 cell count criteria. Hb and BMI values may be useful in prioritizing patients for ART, but did not improve model accuracy.