The incidence of non-pulmonary tuberculosis (TB), which cannot be detected by the traditional test, is on the rise among patients in an advanced stage of HIV infection.

“Several symptoms of non-pulmonary TB — like rapid weight loss and fever — are also symptomatic of AIDS. So, there is a risk of TB remaining undetected and untreated in HIV patients,” said Milan Chhetri, consultant physician of medicine at Apollo Gleneagles Hospitals.

A recent survey by the Calcutta School of Tropical Medicine has revealed that the number of HIV patients suffering from the “hidden”, non-pulmonary TB has jumped from 15 per cent to 28 per cent in the past year.

According to a doctor at the institute, more than 50 per cent of HIV-infected people die of TB.

“Conventional TB is detected by a simple sputum test. The patient is required to collect sputum while he coughs vigorously. But in non-conventional TB, the sputum test may give a negative report, as the lungs are not affected at all. This type of TB targets other organs of the body,” pointed out Chhetri.

The test for non-pulmonary TB is quite expensive. “There is an advanced test, called polymerase chain reaction, for detecting non-pulmonary TB. It is very effective but costly,” he added.

The anti-retroviral therapy, administered to an HIV patient, should not be initiated without treating TB first, as it may engender a chain of physical complications.