Tuberculosis as an Underlying Etiological Factor for Other Human Respiratory Diseases

Tuberculosis (TB) does not occur in isolation from other human illnesses. There are multiple examples where TB combines with one of more comorbidities to amplify its prevalence. Noncommunicable diseases such as diabetes, or lifestyle behaviors including smoking and alcohol misuse, place people at a greater risk of presenting with active TB. But the epidemiological associations between TB and other human conditions are not confined to increasing susceptibility to TB disease. TB, in itself, is an underlying risk factor for the development of downstream respiratory illnesses later in life. This indicates that injury to the host resulted from an episode of TB persists beyond successful eradication of Mycobacterium tuberculosis infection by antimicrobial drug therapy. In this chapter, the specific role of TB in promoting other lung diseases is examined. In particular, TB during childhood increases the risk of development of progressive and poorly reversible airway diseases that include bronchiectasis and chronic obstructive pulmonary disease. It is apparent from the literature that prevention of TB disease offers a potential pathway for reducing the global burden of downstream chronic lung diseases.