World Tuberculosis Day 2022: How Serious is Tuberculous Bacilli And How it Affects Lungs And Other Multiple Parts of The Body

TB is a disease caused by the tuberculous bacilli. The disease mainly affects the lungs (pulmonary TB), but the germ can travel to other parts of the body (extrapulmonary TB) and sometimes multiple parts of the body (military or disseminated TB).

Diabetes is a chronic (long-lasting) disease that damages the body’s ability to convert food into energy. In diabetes, either the insulin is not produced properly or it is not utilized properly. TB is a disease caused by the tuberculous bacilli. The disease mainly affects the lungs (pulmonary TB), but the germ can travel to other parts of the body (extrapulmonary TB) and sometimes multiple parts of the body (military or disseminated TB).

The first report of the association between diabetes mellitus (DM) and tuberculosis (TB) was reported by Avicenna (980-1027AD) over 1000 years back. Diabetes prevalence has an impact on tuberculosis (TB) incidence and TB mortality. It’s linked to a two- to three-fold increased risk of tuberculosis, a two-fold increased risk of death during TB treatment, a four-fold increased risk of TB relapse after treatment, and a two-fold increased risk of multidrug-resistant TB (MDR-TB). TB doubles the risk of diabetes mellitus. Diabetes may be associated with 15% of all tuberculosis cases worldwide.

Once the patient is infected with TB bacilli, there are 4 possible outcomes:

• Immediate clearance of bacilli
• Latent infection (LTBI)
• The onset of active disease (primary disease)
• Reactivation of disease many years later.

Patients with latent TB infection and diabetes are more likely to develop active TB disease than someone without diabetes.

DM favours the growth, viability, and propagation of tubercle bacilli and reduces resistance to infection and repair capacity. There is a higher prevalence of diabetes, as well as impaired glucose tolerance, in patients with tuberculosis. Impaired glucose tolerance is a significant risk factor for developing DM. A part of the hyperglycemia associated with tuberculosis can be attributable to the extreme stress associated with the infection itself.

DM in patients with TB should be managed aggressively. Optimal glycaemic control results in a better outcome; therefore intense efforts should be made to achieve such control. It is imperative to initiate insulin therapy from the very beginning Insulin requirements are high, to begin with, but fall after a few weeks as the infection is controlled.

Anti-tubercular like rifampicin and isoniazid can interact with diabetic medications, leading to fluctuations in blood glucose levels.

Both diseases are linked and need to be treated together to ensure a good outcome. WHO has outlined Activities within the Collaborative framework for care and control of TB and diabetes.

(Authored article by Dr Sneha Kothari, the Consultant Endocrinologist at Global Hospital Parel, Mumbai)