The role of nutritional supplementation in TBM treatment and rehabilitation: a narrative review of mechanisms, evidence, and clinical practice

Tuberculous meningitis (TBM) is the most severe form of tuberculosis, with high mortality and a high burden of neurological and cognitive sequelae. Malnutrition is highly prevalent among patients with TBM, affects both adults and children, and is associated with worse outcomes, yet it remains under-addressed in routine care and clinical guidelines. This narrative review synthesizes the mechanisms, evidence, and clinical practice of nutritional support in TBM. We performed a structured literature search of PubMed/MEDLINE, Embase, the Cochrane Library, and Web of Science, together with the Chinese databases CNKI, Wanfang, and SinoMed, from inception to 31 August 2025, using combinations of terms for TBM, nutrition, malnutrition, micronutrients, and nutritional support. Eligible studies were screened by two reviewers, and evidence was appraised with a hierarchical grading framework and GRADE-derived certainty ratings, with explicit labeling of TBM-specific versus indirect evidence. Mechanistically, TBM produces a hypermetabolic, catabolic state with negative nitrogen balance, gastrointestinal dysfunction, and impaired nutrient absorption, while malnutrition compromises barrier integrity, cell-mediated immunity, and antioxidant defenses. Vitamins D and A, zinc, selenium, and adequate protein and energy intake are mechanistically linked to immune and neurological recovery, but the TBM-specific evidence consists mainly of observational cohorts, case–control studies, and a single case report; randomized controlled trials are absent, and several claims are extrapolated from pulmonary TB, general critical care, or other infections. Nutrition also interacts with anti-tuberculosis drug absorption and adverse effects, and support must be individualized in children and HIV-co-infected patients. Assessment should combine clinical, anthropometric, and biochemical indicators, and the enteral route should be preferred, with parenteral nutrition reserved for enteral failure. We conclude that nutrition should be integrated as a core component of TBM care; clinical benefit claims should be regarded as preliminary until high-quality TBM-specific trials are available. We propose a practical framework for screening, assessment, and individualized support across the treatment and rehabilitation continuum.