Steroids, vitamin D, and TB IRIS in South Africans starting ART
Treating tuberculosis with corticosteroids before antiretroviral therapy (ART) in HIV-positive South Africans lowered levels of several inflammatory markers, while severe vitamin D deficiency was associated with higher inflammatory marker levels regardless of whether TB immune reconstitution inflammatory syndrome (IRIS) developed.
Researchers in Cape Town planned this study to analyze the
impact of vitamin D status and adjunctive corticosteroid
therapy for TB in HIV-positive patients starting ART. The
study included 39 people in whom TB IRIS developed after they
began ART and 42 people without TB IRIS. Overall, of 21 of 81
patients (26%) received corticosteroids before ART for severe
TB. Researchers measured vitamin D and cytokine/chemokine
levels when ART began and 2 weeks later.
Levels of 8 inflammatory markers were significantly lower in
people who took corticosteroids: interferon γ, IP-10,
tumor necrosis factor (TNF), interleukin (IL)-6, IL-8, IL-10,
IL-12p40, and IL-18 (P ≤ 0.02). But corticosteroid
use did not affect chances of TB IRIS, which developed a
median of 12 days after ART began.
Among people with TB IRIS not taking corticosteroids, IL-6,
IL-8, IL-12p40, IL-18, IP-10, and TNF rose significantly
during 2 weeks of ART (P ≤ 0.04).
Vitamin D deficiency, defined as total 25(OH)D below 75
nmol/L, affected 72 people (89%) before ART began. Vitamin D
deficiency when ART began or 2 weeks after ART began did not
affect chances that TB IRIS would develop. However, among
people not taking corticosteroids, median 25(OH)D fell
significantly during 2 weeks of ART (P = 0.004).
Severe vitamin D deficiency, defined as total 25(OH)D below 25
nmol/L, was associated with higher pre-ART TNF, IL-6, and IL-8
regardless of whether TB IRIS developed.
The researchers conclude that corticosteroid therapy modifies
the inflammatory profile of HIV-positive people in whom TB
IRIS develops. They propose that “the association
between severe vitamin D deficiency and elevated
proinflammatory cytokines supports a study of vitamin D
supplementation in HIV-TB co-infected patients starting
ART.”
Source: Anali
Conesa-Botella, Graeme Meintjes, Anna K. Coussens, Helen van
der Plas, Rene Goliath, Charlotte Schutz, Rodrigo
Moreno-Reyes, Meera Mehta, Adrian R. Martineau, Robert J.
Wilkinson, Robert Colebunders, Katalin A. Wilkinson.
Corticosteroid therapy, vitamin D status, and inflammatory
cytokine profile in the HIV-tuberculosis immune reconstitution
inflammatory syndrome.
Clinical Infectious Diseases. 2012; 55: 1004-1011.
For the study abstract
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