Mediastinal tuberculous lymphadenitis: MR imaging appearance with clinicopathologic correlation

Area of Science:

• Radiology
• Infectious Diseases
• Pathology

Background:

• Mediastinal lymphadenitis can be caused by tuberculosis, presenting diagnostic challenges.
• Accurate imaging is crucial for diagnosing tuberculous lymphadenitis and guiding treatment.

Purpose of the Study:

• To define the MR imaging characteristics of mediastinal tuberculous lymphadenitis.
• To correlate MR findings with clinical and pathological data.

Main Methods:

• Retrospective analysis of MR images from 23 patients with confirmed mediastinal tuberculous lymphadenitis.
• Evaluation of node homogeneity, signal intensity, and contrast enhancement.
• Correlation of imaging patterns with clinical symptoms and pathological findings in a subset of patients.

Main Results:

• Three distinct MR imaging patterns were identified in 113 affected lymph nodes.
• Pattern 1 (homogeneous, hyperintense, uniform enhancement) associated with minimal symptoms and granulomas.
• Pattern 2 (inhomogeneous, peripheral enhancement, T2 hyperintensity) common in symptomatic patients, linked to caseation necrosis.
• Pattern 3 (hypointense, no enhancement) seen in asymptomatic patients, corresponding to fibrocalcified nodes.

Conclusions:

• The most frequent MR imaging pattern of mediastinal tuberculous lymphadenitis involves inhomogeneous nodes with T2 hyperintensity and peripheral enhancement.
• This pattern is typically observed in severely symptomatic individuals and reflects caseation necrosis within the tuberculous nodes.