TB prognosis can be affected by numerous factors: coexistent HIV/AIDS, age, chronic comorbidity (for instance, diabetes mellitus, silicosis or cancer), exposure to immunocompromising drugs, smoking, drug and/or alcohol abuse, malnutrition and MDR/XDR-TB status. More scientific evidence is needed in order to understand the role of social determinants on the outcome of disease.
The majority of untreated patients with pulmonary disease die within 1.5 years of developing the first symptoms. The 10-year case fatality rate for untreated HIV-negative sputum smear-positive patients is 53–86% (with an average of 70%); in sputum smear-negative individuals, the rate is 20%. The average duration of the disease from the first symptoms to cure or death, is about 3 years. Unfortunately, failure and death rates are high in MDR- and XDR-TB – the treatment success rate is often less than 50%.