Anaemia in patients with HIV-associated tuberculosis in South Africa: predictive/prognostic value, aetiologies and treatment

Tuberculosis remains the leading cause of death among people living with HIV in sub-Saharan Africa and worldwide. The clinical presentation in such patients is often so non-specific that much tuberculosis remains unsuspected, undiagnosed and is therefore untreated prior to death. Anaemia is one of the most common complications of both HIV and tuberculosis, and is associated with substantial morbidity and mortality. Haemoglobin levels may be a useful biomarker in patients with HIV-associated tuberculosis and anaemia may have predictive value that is under-utilized as an important entry point into the tuberculosis diagnostic algorithm.
This thesis found that moderate or severe anaemia was highly predictive of both prevalent and incident tuberculosis among ambulatory outpatients as well as hospitalised in-patients in South Africa and was also a very strong independent predictor of mortality. Therefore, in high tuberculosis incidence areas in sub-Saharan Africa, all HIV-infected patients with moderate or severe anaemia should be suspected of having tuberculosis and be microbiologically tested for tuberculosis using rapid diagnostic assays regardless of symptomatology. Because anaemia of chronic disease, a process driven by elevated hepcidin levels, is the most common mechanism underlying anaemia in these patients, the majority can be expected to have resolution of anaemia with antiretroviral therapy and anti-tuberculosis therapy alone. The impact of such screening and treatment strategies on HIV-associated tuberculosis in sub-Saharan is not yet known and must be evaluated in future research.