The efficacy of the interferon-γ release assay for diagnosing cervical tuberculous lymphadenitis: A prospective controlled study.

OBJECTIVES/HYPOTHESIS: The whole-blood interferon (IFN)-γ release assay (IGRA) has been studied mainly for diagnosing latent tuberculosis (TB). We prospectively evaluated its diagnostic usefulness in patients with suspected cervical TB lymphadenitis.

STUDY

DESIGN

Prospective cohort study.

METHODS

An IGRA was performed in subjects with suspected TB lymphadenitis. To evaluate the diagnostic performance of the IGRA, we calculated the sensitivity and specificity of culture, radiologic imaging, polymerase chain reaction testing, fine needle aspiration, and excisional biopsy.

RESULT: Of the 271 adult patients with suspected TB lymphadenitis, 42 were diagnosed with the disease. The overall sensitivity and specificity of the IGRA were 78.8% and 95.5%, respectively. When the cutoff value of IFN-γ was set to 0.26 IU/mL, it met the inclusion criteria for suspicious TB lymphadenitis, with sensitivity and specificity of 83.3% and 95.1%, respectively.

CONCLUSIONS

The IGRA is useful in diagnosing TB lymphadenitis, with high sensitivity and specificity.

LEVEL OF EVIDENCE: 4.