Beyond echoes: Interpreting the septated appearance of lymph nodes in sarcoidosis with endobronchial ultrasound.

AIM: To differentiate between various diagnoses of TB, sarcoidosis, and malignancy by looking at echoic features of mediastinal lymph nodes during endobronchial ultrasound (EBUS).

METHOD: 126 patients underwent EBUS, and 208 mediastinal lymph nodes were sampled. EBUS images were reviewed by 3 different individuals blinded to the final diagnosis. Features such as size, shape, margins, echogenicity (heterogeneous or homogeneous), coagulation necrosis sign, and other notable features were observed and compared.

RESULT: Out of 208 lymph nodes, 60/208 (28.8 %) nodes had a diagnosis of TB, 62/208 (29.8 %) had sarcoidosis, 30/208 (14.4 %) had malignancy, and 56/208 (26.9 %) were reactive nodes. A distinct septated appearance was noted in 54.9 % (34/62) of lymph nodes in sarcoidosis, while none of the TB lymph nodes had such a feature. Heterogeneous echogenicity was seen in tubercular nodes (46.7 %) compared to sarcoidosis lymph nodes (32.2 %). Coagulation necrosis sign was seen prominently in TB (63.3 %, 38/60) and in only 4 of 62 lymph nodes with sarcoidosis. Granular appearance was noted in 45.2 % (28/62) of sarcoidosis cases, whereas only 10 % (6/60) of TB nodes showed this feature.

CONCLUSION

The septated appearance of lymph nodes on EBUS can be helpful to predict sarcoidosis, while heterogeneous echotexture and coagulation necrosis in the lymph nodes on EBUS are suggestive of TB.