Differential Analysis Of Crohn’s Disease And Intestinal Tuberculosis

Background: Crohn’s disease(CD)is a chronic non-specific granulomatous disease commonly found in developed countries.In recent years,the incidence rate in China has increased year by year.Intestinal tuberculosis(ITB)is an infectious disease specifically caused by Mycobacterium tuberculosis invading the intestine,it’s rare in developed countries,but one of the most common extrapulmonary tuberculosis diseases in China.The clinical manifestations of the two diseases are extremely similar,and both diseases lack specific diagnostic indicators,which make the identification of the two diseases extremely difficult.How to improve the diagnostic accuracy of these two diseases is a difficult problem to be solved in clinical practice.Objective: To provide evidence of differentiating CD and ITB by learning the characteristics of the clinical symptom,laboratory examination,imaging,colonoscopy and biopsy pathology.Methods:From January in 2015 to July in 2018,the cases of CD or ITB diagnosed in the Department of Gastroenterology,Tongji Hospital affiliated to Tongji Medical College,Huazhong University of Science and Technology were analyzed retrospectively.Results: 1.General: There were 72 patients with CD,48 males(66.67%)and 24 females(33.33%)with an average age of 30.82±14.30 years old,the youngest was 8 years old and the oldest was 70 years old.There were 41 patients with ITB,23 males(56.10%)and 18 females(43.90%)with an average age of 36.49±14.69 years old,the youngest was 16 years old and the oldest was 67 years old.In both groups most of them were young and middle-aged men.There was no significant difference in gender between the two groups(P>0.05),but the patients in CD group were younger than who in ITB group(P<0.05).2.Clinical manifestations and complications: Both CD and ITB patients had abdominal pain,weight loss,and changes in stool characteristics.Abdominal pain,diarrhea,hematochezia,perianal lesions,and fistula sinus were more common in CD;abdominal distension,and lung lesions were more common in ITB(P<0.05).Ascites in ITB was more common than in CD,and exudative ascites was the main(P<0.05).The specificity of abdominal pain was low,but as mentioned above,other statistically significant indicators had high specificity.There were no significant differences in fever,night sweats,weight loss,changes in stool characteristics,parenteral performance,history of abdominal surgery,intestinal obstruction,and intestinal perforation(P>0.05).3.Laboratory: hemoglobin decreased and fecal occult blood positive were more common in CD;T-SPOT.TB and PPD test positive were more common in ITB(P<0.05),the specificity of hemoglobin was low,but the others were high,and T-SPOT.TB also had high sensitivity.There were no significant differences in the erythrocyte sedimentation rate,high-sensitivity C-reactive protein and albumin(P>0.05).The positive rates of p-ANCA in both groups were 0%,and the anti-Saccharomyces cerevisiae antibody(ASCA)in CD was only 4.88%.4.CTE: The lesions of CD and ITB were mostly located in the small intestine and the right colon,and the main manifestation was thickening bowel wall.Lesions in the descending colon、sigmoid colon or rectum,and multi-segment lesions were more common in CD(P<0.05),and the differences of the remaining indicators were not significant(P>0.05).Mesangial vascular enlargement was seen in two patients in CD(3.03%)and one patient in ITB(2.56%).Two of the ITB patients had ring-reinforced lymph nodules(5.13%),and one patient had calcified nodules(2.56%).5.Colonoscopy features: Most CD and ITB patients had irregular ulcers which were mainly in right colon,specially in the terminal ileum or ileocecal valve.Ulcers involving the transverse colon,descending colon,sigmoid colon,rectum,segmental changes,longitudinal ulcers and aphthous ulcers were more common in CD;ring ulcers were more common in ITB(P<0.05).The specificity of the above indicators were high.The sensitivity of the cobblestone signs was low,but the specificity was high.6.Histopathological features: CD and ITB were mainly performed as inflammation.The positive rates of granuloma in CD and ITB were 35.29% and 33.33%,respectively(P>0.05).The positive rates of caseous granuloma in ITB was 10.26%(P<0.05),and that of the acid-fast staining was 21.43%(P>0.05),the granulation tissue was more common in CD(P<0.05),the specificity of the above indications were high.No fissurelike ulcers were seen in both groups.In CD and ITB,there were two cases detected by MTB PCR,both were negative in CD,but positive in ITB.There were two cases detected by Gene Xpert MTB in ITB,and both were positive.Conclusions: 1.In positive indicators for the diagnosis of CD,diarrhea,hematochezia,perianal lesions,fistula sinus,fecal occult blood positive,involving the transverse colon,descending colon,sigmoid colon,rectum,segmental changes,longitudinal ulcers,aphthous ulcers,granulation tissue have high specificity.In addition,although the sensitivity of the cobblestone sign is very low,the specificity is high,which is also an important reference for the identification of CD and ITB.2.In positive indicators for the diagnosis of ITB,abdominal distension,ascites,lung lesions,PPD test,ring ulcers and caseous granuloma have high specificity,T-SPOT.TB has high sensitivity and specificity.In addition,although the acid-fast staining has low sensitivity,the specificity and positive predictive value are 100%,which plays an important role in diagnosing ITB.