Circulating cytokines in pulmonary tuberculosis according to HIV status and dietary iron content.
OBJECTIVE
To evaluate human immunodeficiency virus (HIV) serology, dietary iron and serum concentrations of markers of T-helper type (Th) 1 and Th-2 immune pathways in the setting of tuberculosis (TB).


METHODS
A total of 49 patients with pulmonary TB in rural Zimbabwe, 32 of whom were HIV-positive, were evaluated at presentation and over 10 weeks of anti-tuberculosis treatment.


RESULTS
Interleukin (IL) 12 and neopterin, Th-1 markers, were both elevated at presentation in 92% of the subjects. In contrast, only 23% had elevation of the Th-2 marker, IL-4. Neopterin and IL-6 concentrations decreased over 10 weeks of treatment (P <or= 0.005), but IL-12 and NO(2)/NO(3) increased (P <or= 0.012). IL-12 and neopterin concentrations were higher in HIV-positive subjects compared to HIV-negative subjects (P < 0.0001), while IL-4 concentrations were lower (P = 0.001). Patients were classified as having high vs. normal dietary iron based on the consumption of iron-rich traditional beer. IL-12 and NO(2)/NO(3) concentrations were lower with high dietary iron (P <or= 0.002). HIV-positive individuals with high dietary iron had lower neopterin concentrations compared to HIV-positive individuals with low dietary iron (P < 0.0001).


CONCLUSIONS
Increased iron in pulmonary TB may lead to attenuation of the Th-1 immune response, especially with HIV seropositivity. Iron status may be an important but under-evaluated risk factor in the course of TB and HIV infection.
Center for Sickle Cell Disease and Department of Medicine, Howard University, Washington, DC 20060, USA. vgordeuk@howard.edu
V R
VR
Gordeuk
V M
VM
Moyo
M
M
Nouraie
I T
IT
Gangaidzo
N L
NL
Murphree
Z A R
ZA
Gomo
J R
JR
Boelaert
G
G
Weiss
D000328:Adult; D000995:Antitubercular Agents / Q000627:therapeutic use; D016207:Cytokines / Q000276:immunology; D005260:Female; D006679:HIV Seropositivity / Q000150:complications*; D006801:Humans; D019266:Iron, Dietary / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D012307:Risk Factors; D018417:Th1 Cells / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*; D014397:Tuberculosis, Pulmonary / Q000188:drug therapy / Q000209:etiology / Q000276:immunology*; D055815:Young Adult; D015030:Zimbabwe
D000995:Antitubercular Agents; D016207:Cytokines; D019266:Iron, Dietary; D009566:Nitrates; D009573:Nitrites