PD422 - IMMUNE-MODULATORY NUTRIENTS AS HOST-DIRECTED ADJUNCT THERAPY IN PULMONARY TUBERCULOSIS: A SYSTEMATIC REVIEW AND META-ANALYSIS

PD422

IMMUNE-MODULATORY NUTRIENTS AS HOST-DIRECTED ADJUNCT THERAPY IN PULMONARY TUBERCULOSIS: A SYSTEMATIC REVIEW AND META-ANALYSIS

S. King¹, L. Malan¹, L. Zandberg¹, R. C. Dolman-Macleod ¹, J. Visagie², F. A. E. Hayford³, A. Nienaber^1,*

¹Centre of Excellence for Nutrition, ²Statistics, North-West University, Potchefstroom, South Africa, ³Department of Dietetics, University of Ghana, Accra, Ghana

Rationale: Pulmonary tuberculosis (PTB) is characterised by a chronic inflammatory and hyperactive immune response contributing to lung damage and poor treatment outcomes. This systematic review and meta-analysis aimed to determine the effect of immunonutrients on clinical outcomes when used as adjunct host-directed therapy (HDT) in adults with drug-sensitive PTB.

Methods: This systematic review included randomised controlled trials (RCTs) from Scopus, Web of Science, Cochrane Library, and PubMed; inception-March 2024. Studies of single immunonutrients as adjunct therapy to standard TB treatment in adults with PTB were included. Outcomes included sputum smear/culture conversion, time to conversion, inflammatory markers, mortality, and TB score. Two authors independently screened studies and extracted data; the risk of bias was assessed using RoB 2, and the certainty of evidence was graded using GRADEpro. Meta-analyses were done using R statistical software.

Results: Forty-four studies were included (43 RCTs, 1 quasi-experimental). Arginine supplementation improved sputum smear conversion at eight weeks and reduced CRP. Vitamin C improved smear conversion at eight weeks. Vitamin D reduced TB score at eight weeks, CRP at six weeks, and IFN-γ at 12 weeks, but showed no consistent effect on smear conversion, culture conversion, or mortality. Vitamin A, zinc and their combination showed no significant effects. No eligible trials were identified for vitamin E, selenium, omega-3, nucleotides, iron or glutamine. Certainty of evidence was low to very low.

Conclusion: Arginine, vitamin C, and vitamin D may improve selected clinical outcomes in PTB, including smear conversion, TB score and inflammatory markers (CRP/IFN-γ). Current evidence is inconsistent and limited but suggests a possible supportive role for immune-modulating nutrients in PTB patients. Larger, well-designed trials are needed. 

Disclosure of Interest: None declared