Lack of elevated pre-ART elastase-ANCA levels in patients developing TB-IRIS.

Area of Science:

• Immunology
• Infectious Diseases
• Clinical Medicine

Background:

• Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is a complication in HIV-TB co-infected patients on antiretroviral therapy (ART).
• Neutrophil activation is implicated in TB-IRIS, and anti-neutrophil cytoplasmic antibodies (ANCAs) are markers of neutrophil activation.
• ANCAs may be altered in TB and HIV infections, necessitating investigation in TB-IRIS.

Purpose of the Study:

• To investigate plasma levels of seven ANCAs in patients with HIV-TB co-infection who developed TB-IRIS.
• To compare ANCA levels between TB-IRIS patients, HIV+TB+ controls, HIV+TB- controls, and HIV-TB- controls at various time points during ART.

Main Methods:

• Retrospective study comparing 17 TB-IRIS patients with 17 HIV+TB+ controls, 17 HIV+TB- controls, and 10 HIV-TB- controls.
• Plasma samples collected before ART, and at 3 and 9 months of ART.
• ELISA used to measure levels of 7 ANCAs: anti-PR3, anti-MPO, anti-BPI, anti-elastase, anti-cathepsin, anti-lysozyme, and anti-lactoferrin.

Main Results:

• Pre-ART anti-elastase levels were lower in TB-IRIS patients and HIV+TB- controls compared to HIV+TB+ controls.
• TB-IRIS patients showed a significant decrease in anti-PR3, anti-lysozyme, and anti-lactoferrin levels during ART.
• HIV+TB+ controls exhibited a significant decrease in anti-MPO, anti-lysozyme, and anti-elastase levels during ART.

Conclusions:

• Lower pre-ART anti-elastase levels in TB-IRIS patients, compared to HIV+TB+ controls, may indicate a reduced immune capacity and a specific role for anti-elastase or elastase in TB-IRIS.
• Further research into neutrophil activation dynamics in HIV-TB is needed to understand early TB-IRIS mechanisms.