Author's Reply.

Sir,

We agree with the pertinent remarks of the authors and appreciate their interest in our article. Differentiating tuberculosis from sarcoidosis with absolute certainty is difficult because of overlapping clinical and radiological features.[1] In such cases, tissue sampling is usually done; nevertheless, this distinction may not be achieved in all cases despite sampling. Even with the addition of microbiological investigations, the diagnostic yield is at best around 60%.[2345]

The purpose of this review article was to highlight the imaging similarities and differentiating features between the two entities with only a brief description of clinical and laboratory correlates. We did mention in the imaging-based algorithm proposed in our article about the use of microbiological test—CBNAAT (Gene Xpert) in initial sputum evaluation which is a part of RNTCP guidelines for assessment of tuberculosis.[6] In general, the investigation is routinely performed on any specimen obtained in a suspected case of tuberculosis, for example, bronchoalveolar lavage/fine needle aspiration/biopsy specimens. However, discussion of the implications of it being positive or negative in correlation with the pathological presence or absence of non-caseating granulomas is beyond the range of an imaging-based discussion on sarcoidosis/tuberculosis. Microbiological and pathological evaluation of this spectrum of granulomatous diseases is a complex topic in itself and requires a thorough search and analysis of the literature. Hence, inclusion of the same is beyond the purview and intent of the current article.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.