Mediastinal tuberculous lymphadenitis in adults: constrast-enhanced CT features and pathologic findings

Abstract

Objective The purpose of this study was to evaluate the constrast-enhanced CT features and pathologic findings of mediastinal tuberculous lymphadenitis in adults. Methods 39 patients with 180 lymph nodes diagnosed as mediastinal tuberculous lymphadenitis by operation, mediastinoscopy and biopsy were evaluated on enhanced CT scan, including 20 men and 19 women. The median age of the patients was 26 years(range from 16-67 years). Results Five post-contrast patterns of enhancement were found: (1) inhomogeneous enhancement(28.3%,51 nodes); (2) peripheral rim enhancement(26.1%, 47 nodes); (3) homogeneous enhancement(25.0%, 45 nodes); (4)nonenhancement( 14.4%, 26 nodes); (5) separate enhancement(6.11%, 11 nodes); CT-pathologic correlation demonstrated that patterns of enhancement of mediastinal tuberculous lymphadenitis were correlated with distribution of granulation tissue and caseous areas. 28 patients(71.8%) had a combination of enhancement patterns. 11 patients(28.2%) had a single enhancement pattern. Conclusion Constrast-enhanced CT appearance of mediastinal tuberculous lymphadenitis for diameter of 1.0-2.0 cm was homogeneous enhancement, nonenhancement, inhomogeneous enhancement and peripheral rim enhancement; for diameter of ≥2.0 cm was inhomogeneous enhancement, peripheral rim enhancement, homogeneous enhancement and nonenhancement. Peripheral rim enhancement or separate enhancement can suggest a diagnosis of tuberculosis.