Abstract:
In tuberculosis, cellular immunity is considered to be responsible for the eradication of infection in animal models, the balance between Th l-type cytokines, especially interferon gamma (IFN-y), and Th2-type cytokines, primarily interleukin (IL-4), seems crucial for these effects. Reports on Th l-type and Th2-type cytokines in human tuberculosis are conflicting. The ThllTh2 cytokines balance is crucial determinant of pathology in both HIV-Aids and tuberculosis patients because protective immunity in TB depends on a cellular host response, with an important role for CD4 T- helper cells.
Study objectives
To determine ThllTh2 shift in HIV-I infected MTB patients under AMPATH program in MTRH.
Methodology: This was a cross-sectional study where 21 HIV -1 infected patients with MTB attending the MTRH AMP ATH clinic consecutively over a period of three months and newly diagnosed with pulmonary tuberculosis and who were eligible for the study gave informed consent. CD4 ICD8 counts were determined using TriTEST CD3 FITCICD4 PE/CD45 PerCP test. IFN-y and IL-4 Cytokines level were analyzed using BDTM Cytometric Bead Array and viral loads determined using COBAS TaqMan HIV-I Test kit. Results: In patients with CD4 counts <200 cells/ul the plasma levels of IFN-y (median 19.8pg/ml) were significantly lower than that measured in patients with CD4 counts> 200 cells/ul (median 29.8pg/ml). IL-4 levels in patients with < 200 cells IJlI were (median 48pg/ml) higher than those with CD4 >200 cells/ul (median36.6pg/ml). Patients with CD4< 200 cells/ul, had a statistically significant correlation between IL-4 and Viral load(r=0.812, p=0.004). Patients with CD4=>200 cells/ul, had a statistically significant correlation between IL-4 and viral load (r=0.802 p=0.004). There was a significant correlation between IFN- y and HIV viral loads (r=0.792, p=0.004) and between IFN- y and IL-4 (r=0.679, p=0.022) were significant
Conclusion: There is a reduction in the levels of IFN y in HIV infected patients who are smear positive for MTB and CD4 counts below 200 cells/ul compared to those with CD4 above 200 cells/pi while the levels of IL-4 are higher in patients with <200 cells/ul than those with CD4 >200 cells/ul.