Gut Dysbiosis in Tuberculosis Patients with Malnutrition: A Literature Review

Tuberculosis (TB) remains an international health burden with high morbidity and mortality, especially in low- and middle-income countries. Weight loss and malnutrition often coexist with TB and are linked to poor prognosis. Literature review based on TB, malnutrition, changes of gut microbiota, gut–lung axis, and the role of microbiota metabolite. Gut dysbiosis modulates the immune system through gut–lung axis, with its primary mediators, namely short-chain fatty acids (SCFAs), regulating immune system homeostasis. TB and anti-TB drugs decrease gut microbiota diversity, leading to dysbiosis that worsens immune regulation and thus lowers host immunity to Mycobacterium tuberculosis . TB patients with malnutrition are closely associated with gut dysbiosis through immunological mechanisms and the gut–lung axis, with SCFAs as crucial mediators. This literature review aims to explain the role of gut dysbiosis in malnourished TB patients and highlight pathophysiological implications and intervention approaches.