WHO Criteria Poorly Predict Antiretroviral Treatment Failure

Viral-load monitoring is the gold standard for determining antiretroviral treatment failure, but many countries lack the resources to perform such monitoring. Consequently, they rely on the WHO criteria for treatment failure, which involve CD4-cell counts and clinical disease progression. To determine how well these criteria perform, investigators studied 319 HIV-infected individuals in South Africa during their first year of antiretroviral therapy. All patients had viral-load, CD4-cell–count, and clinical data available at 12 months.

Thirty-three patients met virologic criteria for treatment failure: 19 (6.0%) had definite failure (viral load >10,000 copies/mL at 12 months), and 14 (4.4%) had probable failure (viral load >1000 copies/mL at …