Contribution of a heparin-binding haemagglutinin interferon-gamma release assay to the detection of Mycobacterium tuberculosis infection in HIV-infected patients: comparison with the tuberculin skin test and the QuantiFERON®-TB Gold In-tube

Table 3 Effect of HIV on PPD and HBHA induced IFN-γ levels

	IFN-γ conc. in response to PPD-stimulation			IFN-γ conc. in response to HBHA-stimulation
	n	p	r	n	p	r
CD4⁺ T-cell count	43	0.1499	0.2261	42	0.9029	⁻0.0192
CD4⁺ %	42	0.0034	0.4473	41	0.5827	0.0873
CD4⁺/CD8⁺ ratio	43	<0.0001	0.8586	42	0.4265	0.1245
Viral load	41	0.5777	⁻0.0896	41	0.4643	⁻0.1175

Pearson correlation was used to measure the association between PPD- or HBHA-induced IFN-γ responses and four different predictor variables associated with HIV-infection severity: absolute CD4⁺ T-cell counts, CD4⁺ percentages (%), CD4⁺/CD8⁺ ratios and viral loads. Significant p values are in bold type (p < 0.05). conc = concentration; n = number of tests; r = pearson's product moment coefficient.

ISSN: 1471-2334