Iron redistribution a risk factor for TB in HIV infection

The clinical and nutritional management of HIV and tuberculosis co-infection may be improved by better understanding and managing iron-related tuberculosis risk factors, according to a recent study.

Joann M. McDermid, an assistant professor of global health and nutrition at Cornell University, and her team studied multiple host iron status biomarkers in 1,139 adult participants in a study conducted in the Gambia. Since iron influences the pathogenesis of TB, the researchers attempted to determine how host iron status measured at HIV diagnosis and how genotypes related to host iron metabolism were connected with incident TB, BioMedCentral reports.

The authors of the study found that iron status biomarkers such as hemoglobin, plasma transferrin and ferritin were significantly associated with TB after an adjustment was made for TB susceptibility factors.

The team concluded that evidence of host iron redistribution at HIV diagnoses was associated with incident TB and that genetic influences on iron homeostasis could also be involved. When low hemoglobin was considered in combination with other iron status biomarkers, the findings pointed to a mechanism whereby iron redistribution and anemia are likely due to bacteria and/or viral processes and the host's infection immune response.

McDermid and her team suggested that iron supplementation may not be safe or efficacious under the circumstances of TB and HIV co-infection, BioMedCentral reports.

Additional research into iron-related TB risk factors could improve disease outcome, particularly in areas where food malnutrition and insecurity co-exist, according to the authors.

The study was published on Tuesday in BMC Infectious Diseases.