ABSTRACT
Objective To evaluate the value of T-cell spot of tuberculosis test (T-spot.TB) in differential diagnosis of Crohn's disease and intestinal tuberculosis.Methods From May 2010 to October 2010,in Xijing hospital,Fourth Military Medical University,the peripheral blood samples of 126 patients were collected and peripheral blood mononuclear cells were isolated with density gradient centrifugation.T-spot.TB was conducted according to the kit instructions.The clinical diagnosis of Crohn's disease and intestinal tuberculosis was according to clinical manifestations, imaging,endoscopy,pathology,laboratory tests and on empirical anti-TB treatment response.The sensitivity and specificity of T-spot.TB in diagnosis of Crohn's disease and intestinal tuberculosis was analyzed.Results Fifteen patients were diagnosed as Crohn's disease (11.9％,15/126),14 patients were intestinal tuberculosis (11.1％,14/126) and 40 patients were extraintestinal tuberculosis (31.7％,40/126).The positive rate of T- spot.TB in Crohn's disease,intestinal tuberculosis,extra-intestinal tuberculosis and other diseases was 1/15,12/14,70％ (28/40) and 0％ (0/57),respectively.Thedifference between the groups was statistically significant (P =0.00).There was statistically significant difference of T-spot.TB positive rate between Crohn's disease and intestinal tuberculosis (x2 =70.58,P=0.00).The sensitivity and specificity of T- spot.TB in Crohn's disease detection was 93.3％(14/15) and 87.5％(14/16),in intestinal tuberculosis was 85.7％(12/14) and 93.3％ (14/15).The negatively predictive value of Crohn's disease was higher [87.5％ (14/16)] than that of intestinal tuberculosis [12.5％ (2/16)].Conclusion T-spot.TB is helpful for differential diagnosis of Crohn's disease and intestinal tuberculosis.