Diagnostic value of transbronchial needle aspiration cytology in sarcoidosis

Sarcoidosis is a systemic granulomatous inflammation that occurs as a result of disturbed immune regulation in individuals exposed to certain environmental agents. Although tissue sampling is considered the "gold standard" for the diagnosis of sarcoidosis, a medically treated disease, minimally invasive diagnostic methods are preferred instead of surgical tissue sampling. Transbronchial needle aspiration has been reported as an effective diagnostic method.

In this study, transbronchial needle aspiration cytology samples were assessed from 38 patients where sarcoidosis was suspected clinically and radiologically. The existence of epithelioid histiocytes and/or giant cells that formed granulomas was used as a cytological diagnostic criterion for chronic granulomatous inflammation. The presence of lymphocytes and/or germinal center cells, and of histiocytes in lymph nodes was regarded as adequate sampling criteria.

A total of 31 out of the 38 patients were diagnosed as sarcoidosis with clinical, radiological and microbiological findings, after chronic granulomatous inflammation was considered by cytologic assessment. Cytologic diagnosis was achieved in: 4 of 7 patients with sampling from a single lymph node region, 25 of 28 patients with sampling from two different lymph node regions and 2 of 3 patients with sampling from three different lymph node regions. Two of the 7 patients who could not be diagnosed cytologically underwent a transbronchial parenchyma biopsy and the rest were diagnosed histologically from mediastinoscopic lymph node sampling.

We would like to emphasize that transbronchial needle aspiration is a successful diagnostic method. We highlighted the adequacy criteria of cytological sampling and the encountered cytological findings of chronic granulomatous inflammation.