Dilemma of diagnosing thoracic sarcoidosis in tuberculosis-endemic regions: An imaging-based approach. Part 2

Abstract

The second part of the review discusses the role of different existing imaging modalities in the evaluation of thoracic sarcoidosis, including chest radiograph, computed tomography, magnetic resonance imaging, endobronchial ultrasound, and positron emission tomography. While summarizing the advantages and pitfalls of each imaging modality, the authors propose imaging recommendations and an algorithm to be followed in the evaluation of clinically suspected case of sarcoidosis in tuberculosis-endemic regions.

Seeds in the Lungs: A Pseudo-Miliary Pattern of Sarcoidosis

“…A majority of miliary sarcoidosis cases were shown to have a subtle peri-lymphatic pattern thus, coining the term “pseudo-miliary” [ 2 , 6 ]. In our case, there was a predominant peri-lymphatic and subpleural pattern of the nodules, which may be suggestive of a pseudo-miliary pattern.…”

Imaging of Pulmonary Sarcoidosis—A Review

“…Enlargement of mediastinal and hilar lymph nodes is a hallmark of sarcoidosis, reported on CT in up to 84-97% of cases [38][39][40][41], and most commonly involving stations 4R, 7, 11L and 11R [40]; the classical Garland's triad of bilateral hilar and right paratracheal nodal enlargement will be known to most readers [42]. Not surprisingly, the distribution and extent of nodal enlargement are best evaluated on CT [43].…”

“…On the whole, symmetrical hilar nodal enlargement most often points to a diagnosis of sarcoidosis and away from lymphoma, other malignancies and tuberculosis (TB); in TB, calcification is more often unilateral and along predictable lymphatic drainage pathways [44]. Necrosis of lymph nodes is recognised in sarcoidosis but should prompt a search for an alternative aetiology, such as TB [39]. Nodal calcification, present in 44-53% of patients, also tends to be bilateral and may have a focal pattern (as opposed to complete, asymmetrical nodal calcification which is more commonly observed in TB) [41,44]; so-called 'egg-shell' calcification is also reported [45].…”

Thoracic sarcoidosis versus tuberculosis: Need for a multi-disciplinary approach

“…We read with great interest the article titled “Dilemma of diagnosing thoracic sarcoidosis in tuberculosis endemic regions: An imaging based approach” by Bhalla et al . [ 1 ] in the October-December 2017 issue of the Indian Journal of Radiology and Imaging (Volume 27, Issue 4). The article focused and succeeded in projecting in great detail the nuances of differentiating between sarcoidosis and its close mimic tuberculosis (TB).…”