Clinical Study On Differential Diagnosis Of Crohn’s Disease And Intestinal Tuberculosis

Background: Crohn’s disease(CD)and Intestinal tuberculosis(ITB)are easily misdiagnosed,due to their very similar disease clinical characteristics.The differential diagnosis of these two diseases has always been a difficulty faced by clinicians.In recent years,with the increasing incidence of CD in China,where is also the epidemic area of tuberculosis,the difficulty of differential diagnosis has been further improved.It is very necessary to find a fast and accurate differential diagnosis method.Objective: To explore the clinical manifestations,laboratory examinations,endoscopic findings,histopathology,and imaging characteristics of CD and ITB by meta-analysis and retrospective analysis,and provide evidence for the differential diagnosis.Method: 1.A systematic literature search was conducted in PUBMED,EMBASE,CBM,CNKI,VIP and WANFANG for literatures related to the differential diagnosis of CD and ITB from inception until January 2020.QUADAS-2 tool was used to evaluate the risk of bias,and Review Manager 5.3 and STATA 12.1 software were used for data processing.Mete analysis was performed on each variable included and sensitivity analysis was carried out on the variables with significant heterogeneity(I2 > 50%).2.The clinical manifestations,laboratory tests,endoscopic findings,histopathology and radiological features of 52 patients with CD and 80 patients with ITB,who were diagnosed in the second affiliated hospital of Lanzhou University from June 2015 to November 2019,were retrospectively analyzed.Result: 1.Twenty four studies,including 1648 patients with CD and 1078 patients with ITB,involving 75 variables were included in the study.If the final combined effect value OR of each variable >1,and the lower bound of 95% CI also >1,the variables were thought to be favored CD,which included male gender,history of appendectomy,diarrhea,hematochezia,perianal disease,fistula,extraintestinal manifestations;positive fecal occult blood,p-ANCA,ANCA or elevated CRP in laboratory tests;endoscopic findings of longitudinal ulcers,mucosal bridge,cobblestone appearance,aphthous ulcer,luminal stricture,ileocecal stenosis,and involvement of terminal ileum,transverse colon,rectum,or anal canal;and radiologic findings of asymmetrical wall thickening,mesenteric fibrous adipose hyperplasia,comb sign,phlegmon,abscesses,fistulas,and lumen stenosis.To thecontrary,If the final combined effect value OR of each variable <1,and the upper bound of 95% CI also <1,the variables were thought to be favored ITB,which included fever,night sweats,ascites,endoscopic findings of transverse or annular ulcers,rat-bite ulcer,patulous ileocecal valve,scarring,and involvement of the Ileocecal valve or ascending colon;pathological findings of granuloma formation,caseous granuloma or positive TB-PCR;and radiologic findings of lung involvement,patulous ileocecal valve,ascites,peritoneal lymph node calcification or necrosis.2.In the retrospective analysis,there were 52 patients in the CD group,including32 males(61.5%)and 20 females(38.5%),with an average age of 34.21±13.79years;and 80 patients in the ITB group,including 43 males(53.8%)and 37 females(46.2%),with an average age of 39.05 ± 16.61 years.There was no significant difference in sex composition ratio and age between the two groups(P>0.05).The proportion of minority patients in ITB group was significantly higher than that in CD group(P < 0.05).The proportion of minority patients in ITB group was significantly higher than that in CD group(P < 0.05).The clinical manifestations,laboratory examination,endoscopy,histopathology and imaging characteristics of the two groups were compared and analyzed,and variables with statistical differences between the two groups were selected(P < 0.05).Favorable variables for diagnosing CD included abdominal pain,history of appendectomy or any other intestinal operation,fistula or sinus tract,perianal disease;involvement of small intestine;endoscopic findings of longitudinal ulcer,deep and large ulcer,cobblestone appearance;pathological findings of lymphocyte aggregation;imaging characteristics of asymmetric thickening wall,intestinal wall strengthening effect,lumen stenosis,comb sign,and segmental involvement.Favorable variables for diagnosing ITB included night sweats,history of tuberculosis;elevated CRP or positive T-SPOT in laboratory tests;endoscopic findings of transverse or annular ulcers or superficial ulceration;pathological findings of caseous granuloma,caseous necrosis or positive TB-PCR for tissue specimens;imaging characteristics of lung involvement,symmetrical thickening wall,retroperitoneal lymph node enlargement,ascites or diffuse thickening of membrane.Conclusion: 1.There have few specific indexes in clinical manifestations and laboratory examinations for differential diagnosis of CD and ITB.Endoscopy,histopathology,CTE or MRE are still the main methods for differential diagnosis.2.Variables including appendectomy or other intestinal surgery history of perianal lesions,blood stool,perianal lesions,sinus tract or fistula formation,or parenteral manifestations are highly suggestive for the diagnosis of CD,but with low sensitivity.Deep and large ulcer,segmental involvement and cobblestone appearance are typical endoscopic presentations of CD.Pathological findings of lymphoid aggregates is suggestive to the diagnosis of CD.Asymmetric thickening of intestinal wall,leaping lesions,mesenteric fiber fat hyperplasia and comb sign in CTE/MRE have high specificity for diagnosis.3.Most of the ITB patients had history of tuberculosis,with clinical manifestations of night sweats,fever or ascites.T-SPOT has high specificity for diagnosis of ITB.The main involvements of lesions are ileocecal region and the rightcolon.Transverse or annular ulcers,rat-bite ulcer and patulous ileocecal valve are typical endoscopic presentations of ITB.Definitive diagnosis of ITB can be made with pathological features of aseoid granuloma or necrosis,tissue PCR test positive.Imaging features including pulmonary involvement,abdominal effusion,calcification or necrosis of abdominal lymph nodes,and peritoneal thickening are suggestive for the diagnosis of ITB.4.By the influence of multiple factors,such as the incidence of patients,the severity of disease,the experience of doctors in diagnosis and treatment,and the degree of disease cognition,may lead to differences in the results of different studies.