“The cytokine profiles of the inflammatory response in chronic granulomatous encephalitis caused by Mycobacterium tuberculosis do not influence the patient's clinical presentation"

Abstract

Introduction

Central nervous system tuberculosis (CNS-TB) is the most lethal form of tuberculosis, characterized by severe clinical manifestations and distinctive histopathological changes. Although several cytokines are implicated in the immune response to Mycobacterium tuberculosis, their relationship with disease severity and histological alterations remains unclear. This study aimed to evaluate the associations between cytokine expression, histopathological changes, and clinical features in patients with CNS-TB.

Methods

We conducted a retrospective, observational, cross-sectional, descriptive study of 25 biopsies that fulfilled criteria for CNS-TB at the National Institute of Neurology and Neurosurgery “Manuel Velasco Suárez.” Cases were classified according to the Suzaan Marais criteria. Immunohistochemistry was performed to assess IL-1β, IL-4, IL-10, IL-17, IL-23, TNF-α, and IFN-γ expression in meningeal and parenchymal tissues.

Results

Strong expression of IL-1β, IL-17, IL-23, and TNF-α was observed in glial cells, vascular endothelial cells, and macrophages, particularly within inflammatory and vascular lesions.

Conclusions

Although no direct correlation was found between cytokine expression and clinical severity, the findings support a predominant pro-inflammatory response mediated by IL-1β, IL-17, IL-23, and TNF-α, associated with tissue and vascular damage. The elevated cytokine expression in foam cells suggests a potential role in local immune regulation in CNS-TB.