The prevalence and drug sensitivity of tuberculosis among patients dying in hospital in South Africa

A large, systematic postmortem study carried out in South Africa by Ted Cohen and colleagues has revealed that 94% of deceased patients were HIV infected and 50% had culture-positive tuberculosis at the time of death. These data, which reveal that the toll of tuberculosis in young people (age 20-45) in KwaZulu-Natal is higher than we previously thought, are published this week in the open access medical journal PLoS Medicine.

Every year, nearly 10 million people develop tuberculosis—a contagious bacterial infection that affects the lungs and other parts of the body—and nearly two million people die from the disease. Tuberculosis is caused by Mycobacterium tuberculosis. People who are infected with HIV, the virus that causes AIDS, are particularly susceptible to tuberculosis because of their weakened immune system.

Postmortem studies which assess contributory causes of death in patients admitted to hospital in an area where mortality from TB and TB/HIV is extremely high are infrequently done, but provide key data that can enable optimization of HIV and TB treatment programs.

The researchers determined the prevalence and drug sensitivity of tuberculosis among patients dying in a public hospital in KwaZulu-Natal, South Africa. The authors found that the majority of the deceased, who at the time of death were receiving tuberculosis treatment, were infected with M. tuberculosis strains that were fully susceptible to antibiotics. This suggests that the diagnosis of tuberculosis was made too late to alter the fatal course of the infection.

These findings suggest that improving the early diagnosis of tuberculosis, for example, routine screening for tuberculosis among HIV-positive patients, and speedier initiation of treatment for both tuberculosis and HIV could reduce the global death toll from tuberculosis.