CSF Hypo-Inflammation Drives Mortality in HIV-Associated Tuberculous Meningitis

Area of Science:

• Neuroscience
• Immunology
• Infectious Diseases

Background:

• Tuberculous meningitis (TBM) poses a significant mortality risk, especially in individuals with HIV.
• Corticosteroid therapy improves outcomes in HIV-negative TBM but not in those with HIV.
• Understanding immune responses in HIV-associated TBM is crucial for improving patient survival.

Purpose of the Study:

• To investigate the association between local immune dynamics in cerebrospinal fluid (CSF) and mortality in adults with HIV-associated TBM.
• To identify specific immune mediators that predict outcomes in this patient population.

Main Methods:

• Measured baseline CSF immune signaling mediators in 149 adults with HIV and TBM in Uganda.
• Patients received standard antimycobacterial and corticosteroid therapy.
• Correlated immune mediator concentrations with 90-day mortality.

Main Results:

• Non-survivors exhibited more severe TBM and lower blood CD4 T cell counts.
• Mortality was strongly associated with CSF hypo-inflammation.
• Higher CSF interferon-gamma (IFN-γ) levels correlated with lower mortality; low IFN-γ increased death risk.
• Intermediate CSF interleukin-13 levels were associated with reduced mortality.
• The highest mortality was observed in patients with both CD4 depletion and low CSF IFN-γ.

Conclusions:

• Mortality in HIV-associated TBM treated with dexamethasone is linked to reduced CSF inflammation.
• Current steroid therapy may not be sufficient for all patients.
• Personalized immunotherapy strategies targeting specific immune responses are needed to improve outcomes in HIV-TBM.