[The clinical application of videomediastinoscopy combined with the examination of CD(4)/CD(8) in the diagnosis of mediastinal tuberculosis and sarcoidosis].

OBJECTIVE

To evaluate the role of videomediastinoscopy combined with the examination of CD(4)/CD(8) in the diagnosis of tuberculosis and sarcoidosis of the mediastinum.

METHODS

The clinical records of 90 patients who underwent videomediastinoscopy from February 2003 to September 2005 were retrospectively reviewed. The expression of CD(4)/CD(8) was studied using immunohistochemical method in the tissues from 57 cases with a diagnosis of tuberculosis or sarcoidosis and noncaseating granuloma without classical "sarcoid" pathology obtained by videomediastinoscopy.

RESULTS

Sarcoidosis was diagnosed in 37 patients, tuberculosis in 14 patients, lymphoma in 15 patients, nodal metastasis in 18 patients, noncaseating granuloma without classical "sarcoid" in 6 patients. The diagnostic accuracy was 93.3% (84/90). The expression of CD(4) and CD(8) in sarcoidosis was (65 +/- 13)% and (9.4 +/- 2.6)%, respectively. While the expression of CD(4) and CD(8) in tuberculosis was (41 +/- 11)% and (11.8 +/- 3.4)%, respectively. The rate of CD(4)/CD(8) in sarcoidosis was higher than that in tuberculosis (7.3 +/- 1.8 and 3.6 +/- 1.1, respectively, t = 1.883, P = 0.000). The accuracy, specificity and sensitivity for diagnosis of sarcoidosis was 90.2%, 85.7% and 91.9%, respectively, if the cutoff value of CD(4)/CD(8) was 5. No complication or mortality was reported.

CONCLUSION

Videomediastinoscopy is an effective procedure for the diagnosis of mediastinal diseases. The examination of CD(4)/CD(8) adds more information to the differentiation of tuberculosis from sarcoidosis.