behet 's disease ( bd ) is a chronic , multisystemic , relapsing inflammatory disorder , characterized by recurrent oral ulcers , genital ulcers , uveitis , and skin lesions .
it also attacks other systems involving the musculoskeletal system , blood vessels , nervous system , and gastrointestinal tract .
bd is predominantly found in eastern mediterranean countries and the eastern rim of asia , including china .
when bd patients have predominantly gastrointestinal symptoms and show gastrointestinal lesions with certain objective measures , the disease is defined as intestinal bd .
the prevalence of intestinal bd varies from 0% to 60% of all bd patients with geographic and ethnic differences .
the ileocecal region is the most commonly involved region , and abdominal pain , diarrhea , and gastrointestinal bleeding are common symptoms .
crohn 's disease ( cd ) is a relapsing and transmural inflammatory disease which can affect the entire gastrointestinal tract .
typical presentations include the presence of longitudinal ulcers with a cobblestone appearance , skip lesions , and the development of complications such as strictures and fistulas .
cd also has extraintestinal manifestations , such as oral ulcers , arthralgia , erythema nodosum , and autoimmune hepatic diseases .
both diseases commonly have a young age of onset , nonspecific gastrointestinal symptoms , similar extraintestinal manifestations , and chronic , waxing , and waning course .
there are only a few comparative studies regarding the differential diagnosis , which were conducted in korean patients , and no comparative study has been done in chinese patients .
we carried out this retrospective study to elucidate the clinical and colonoscopic features in chinese patients with intestinal bd or cd , and to identify valuable strategies for the differential diagnosis .
from january 1983 to january 2010 , 50 intestinal bd patients and 219 cd patients were hospitalized in peking union medical college hospital , a tertiary academic hospital , in beijing , china . among them , patients ( 35 intestinal bd patients and 106 cd patients ) who had ulcerative lesions in the terminal ileum or colon under colonoscopy and had no history of gastrointestinal operation except appendectomy were enrolled in this study .
patients diagnosed with ulcerative colitis , celiac disease , intestinal tuberculosis , malignancy , or other recognized causes of intestinal inflammation were excluded .
behet 's disease was diagnosed based on the criteria from the bd research committee of japan in 1987 .
briefly , the criteria include four major features ( recurrent oral aphthous ulcers , eye lesions , genital lesions , and skin lesions including erythema nodosum , subcutaneous thrombophlebitis , acne - like lesions , and cutaneous hypersensitivity ) and five minor features ( arthritis , gastrointestinal lesions characterized by ileocecal ulcers , epididymitis , vascular lesions , and lesions of the central nervous system ) . diagnosis of complete type bd requires all four major features .
the incomplete type needs three major features , or two major plus two minor features , or typical ocular symptoms plus one major or two minor features .
the suspected type needs two major features , or one major plus two minor features . when patients with bd had predominantly gastrointestinal symptoms with endoscopic , histologic , and/or radiographic evidence of gastrointestinal lesions , they were diagnosed as intestinal bd . in this study , 3 ( 8.6% ) , 26 ( 74.3% ) , and 6 ( 17.1% ) patients were diagnosed as complete , incomplete , and suspected bd , respectively .
morphological features include : ( 1 ) discontinuous and asymmetrical mucosal involvement ; ( 2 ) deep mucosal longitudinal ulcers ; ( 3 ) transmural inflammation ; ( 4 ) a rigid intestinal wall ; and ( 5 ) presence of an enterocutaneous or entero - enteric fistula and/or chronic perianal disease .
pathological features include : ( 1 ) normal mucus content in the goblet cells of the inflamed region ; ( 2 ) lymphocyte aggregation in the mucosa and submucosa ; ( 3 ) noncaseating granulomas ; ( 4 ) longitudinal ulcers ; and ( 5 ) transmural inflammation . for definite diagnosis of cd ,
the following criteria were used : the presence of at least three different histologic features ; or the presence of noncaseating granulomas on histology with at least one other feature ; or the resolution of symptoms and morphologic features after 312 months treatment .
data were collected including demographics ( gender , age and disease duration ) , clinical manifestations ( disease distribution , gastrointestinal symptoms , extraintestinal manifestations , and gastrointestinal complications ) , and colonoscopic findings . the disease distribution was determined by endoscopic and radiologic examinations .
gastrointestinal complications included perforation , fistulae , intestinal obstruction and massive gastrointestinal hemorrhage which were associated with hemodynamic instability , acute anemia , and/or the need for blood transfusion .
colonoscopic features included the ulcer distribution ( focal involvement , segmental involvement ) , the number of ulcers in a local segment ( 1 , or  2 ) , ulcer type ( longitudinal ulcer , circumferential ulcer , aphthous ulcer or irregular ulcer ) , cobblestone appearance , pseudo - polyps , and stricture .
focal involvement was defined as one local area with ulcerative lesions or two adjacent areas involved by continuous ulcerative lesions .
a circumferential ulcer was defined as a round or transverse , deep and well - demarcated ulcer .
an aphthous ulcer was defined as a small ( < 1 cm ) , punched out , raised or a flat lesion with a white center [ figure 1a  c ] .
the cobblestone appearance was defined as a mucosal pattern with raised nodules , resembling the paving of the  roman  road .
pseudo - polyps are defined as polypoid lesions which are usually small and isolated or multiple and scattered , though they can sometimes be giant in size .
all images of colonoscopic examinations were reviewed by an expert endoscopist who was blinded from other information .
histologic features of biopsy specimens , which were paraffin - embedded and stained with hematoxylin and eosin , were evaluated for the presence of epithelioid granulomas and the appearance of vasculitis .
( a ) a longitudinal ulcer in a patient with crohn 's disease ( cd ) .
( b ) a circumferential ulcer in a patient with intestinal behet 's disease . ( c ) an aphthous ulcer in a patient with cd .
differences in quantitative data between the two groups were examined statistically through univariate analysis using an independent t - test and chi - squared test for continuous and categorical variables , respectively .
p values were two - tailed , and the significance level was set at p < 0.05 . for multivariate logistic regression analysis , predictors with a p < 0.3 were entered to select independent discriminating predictors .
receiver operating characteristic ( roc ) curves were constructed to evaluate the discriminating ability of predictors .
statistical analyses were performed using statistical package for the social sciences ( spss ) 19.0 statistical software ( spss inc .
from january 1983 to january 2010 , 50 intestinal bd patients and 219 cd patients were hospitalized in peking union medical college hospital , a tertiary academic hospital , in beijing , china . among them , patients ( 35 intestinal bd patients and 106 cd patients ) who had ulcerative lesions in the terminal ileum or colon under colonoscopy and had no history of gastrointestinal operation except appendectomy were enrolled in this study .
patients diagnosed with ulcerative colitis , celiac disease , intestinal tuberculosis , malignancy , or other recognized causes of intestinal inflammation were excluded .
behet 's disease was diagnosed based on the criteria from the bd research committee of japan in 1987 . briefly , the criteria include four major features ( recurrent oral aphthous ulcers , eye lesions , genital lesions , and skin lesions including erythema nodosum , subcutaneous thrombophlebitis , acne - like lesions , and cutaneous hypersensitivity ) and five minor features ( arthritis , gastrointestinal lesions characterized by ileocecal ulcers , epididymitis , vascular lesions , and lesions of the central nervous system ) .
the incomplete type needs three major features , or two major plus two minor features , or typical ocular symptoms plus one major or two minor features .
the suspected type needs two major features , or one major plus two minor features . when patients with bd had predominantly gastrointestinal symptoms with endoscopic , histologic , and/or radiographic evidence of gastrointestinal lesions , they were diagnosed as intestinal bd . in this study , 3 ( 8.6% ) , 26 ( 74.3% ) , and 6 ( 17.1% ) patients were diagnosed as complete , incomplete , and suspected bd , respectively .
morphological features include : ( 1 ) discontinuous and asymmetrical mucosal involvement ; ( 2 ) deep mucosal longitudinal ulcers ; ( 3 ) transmural inflammation ; ( 4 ) a rigid intestinal wall ; and ( 5 ) presence of an enterocutaneous or entero - enteric fistula and/or chronic perianal disease .
pathological features include : ( 1 ) normal mucus content in the goblet cells of the inflamed region ; ( 2 ) lymphocyte aggregation in the mucosa and submucosa ; ( 3 ) noncaseating granulomas ; ( 4 ) longitudinal ulcers ; and ( 5 ) transmural inflammation . for definite diagnosis of cd , the following criteria were used : the presence of at least three different histologic features ; or the presence of noncaseating granulomas on histology with at least one other feature ; or the resolution of symptoms and morphologic features after 312 months treatment .
data were collected including demographics ( gender , age and disease duration ) , clinical manifestations ( disease distribution , gastrointestinal symptoms , extraintestinal manifestations , and gastrointestinal complications ) , and colonoscopic findings . the disease distribution was determined by endoscopic and radiologic examinations .
gastrointestinal complications included perforation , fistulae , intestinal obstruction and massive gastrointestinal hemorrhage which were associated with hemodynamic instability , acute anemia , and/or the need for blood transfusion .
colonoscopic features included the ulcer distribution ( focal involvement , segmental involvement ) , the number of ulcers in a local segment ( 1 , or  2 ) , ulcer type ( longitudinal ulcer , circumferential ulcer , aphthous ulcer or irregular ulcer ) , cobblestone appearance , pseudo - polyps , and stricture .
focal involvement was defined as one local area with ulcerative lesions or two adjacent areas involved by continuous ulcerative lesions .
a circumferential ulcer was defined as a round or transverse , deep and well - demarcated ulcer .
an aphthous ulcer was defined as a small ( < 1 cm ) , punched out , raised or a flat lesion with a white center [ figure 1a  c ] .
the cobblestone appearance was defined as a mucosal pattern with raised nodules , resembling the paving of the  roman  road .
pseudo - polyps are defined as polypoid lesions which are usually small and isolated or multiple and scattered , though they can sometimes be giant in size .
all images of colonoscopic examinations were reviewed by an expert endoscopist who was blinded from other information .
histologic features of biopsy specimens , which were paraffin - embedded and stained with hematoxylin and eosin , were evaluated for the presence of epithelioid granulomas and the appearance of vasculitis .
( a ) a longitudinal ulcer in a patient with crohn 's disease ( cd ) .
( b ) a circumferential ulcer in a patient with intestinal behet 's disease . ( c )
differences in quantitative data between the two groups were examined statistically through univariate analysis using an independent t - test and chi - squared test for continuous and categorical variables , respectively .
p values were two - tailed , and the significance level was set at p < 0.05 . for multivariate logistic regression analysis , predictors with a p < 0.3 were entered to select independent discriminating predictors .
receiver operating characteristic ( roc ) curves were constructed to evaluate the discriminating ability of predictors .
statistical analyses were performed using statistical package for the social sciences ( spss ) 19.0 statistical software ( spss inc . , chicago , il , usa ) .
table 1 shows the differences in demographics and clinical features between intestinal bd patients and cd patients . there were a higher prevalence of females and a slightly earlier onset in intestinal bd patients compared to cd patients ( p = 0.010 and 0.136 , respectively ) .
there was no significant difference in the duration from the onset of gastrointestinal symptoms to diagnosis between two groups ( p = 0.738 ) .
comparison of the demographic and clinical manifestations between intestinal bd and cd bd : behet s disease ; cd : crohn s disease ; sd : standard deviation .
although the involvement of both the ileum and colon was most common in both intestinal bd patients ( 91.4% ) and cd patients ( 82.1% ) , there was still a significant difference in the disease distribution between two groups ( p = 0.005 ) .
there was an increased tendency for intestinal bd patients to have involvement of the upper gastrointestinal tract ( 17.1% ) compared to cd patients ( 5.7% ) ( p = 0.073 ) .
the most frequent gastrointestinal symptom of both diseases was abdominal pain ( p = 0.517 ) .
massive gastrointestinal hemorrhage and fever were more frequent in intestinal bd patients ( p = 0.022 and 0.048 , respectively ) , while diarrhea , intestinal obstruction , and perianal lesions including perianal abscesses , fistula , and/or anal fissure were more common in cd patients ( p = 0.002 , 0.010 , and 0.027 , respectively ) .
intestinal bd , as a multisystemic disease , involved more extraintestinal symptoms compared to cd ( p = 0.001 ) . for example , genital ulcers and skin lesions were very common in intestinal bd patients , while they were rare in cd patients ( p < 0.001 ) . furthermore
based on multivariate logistic regression analysis of demographics and clinical features , diarrhea and extraintestinal manifestations were found to be two independent discriminating predictors ( p = 0.048 and 0.008 , respectively ) .
based on colonoscopy , there were significant differences in the ulcer distribution ( p < 0.001 ) , ulcer size ( p = 0.017 ) , ulcer type ( p < 0.001 ) , and ulcer number ( p = 0.014 ) in a local area between the two groups [ table 2 ] .
focal involvement , ileocecal valve deformity , solitary ulcer , large ulcers ( ulcer size > 2 cm ) , and circumferential ulcers were more common in intestinal bd patients ( p = 0.003 , 0.003 , 0.014 , 0.013 , and 0.003 , respectively ) , while segmental involvement , longitudinal ulcers , a cobblestone or nodular appearance , and pseudo - polyps were more common in cd patients ( p = 0.003 , 0.008 , 0.023 , and 0.002 , respectively ) .
there was no significant difference in the frequency of aphthous ulcers between the two groups ( p = 0.679 ) .
comparison of the colonoscopic features between intestinal intestinal bd and cd ( n ( % ) ) * ileocecal region represents terminal ileum and/or cecum .
bd : behet s disease ; cd : crohn s disease . according to multivariate logistic regression analysis of colonoscopic features ,
the ulcer distribution , ulcer size , ulcer type and pseudo - polyps were independent discriminating predictors ( p = 0.006 , 0.021 , 0.002 , and 0.041 , respectively ) .
the histology of mucosa biopsies in 11.4% cd patients revealed noncaseating epithelioid granulomas . neither the appearance of vasculitis nor granulomas was found in the mucosa biopsies of intestinal bd patients .
no dysplasia or cancer was found in the mucosa biopsies of any patient . among the independent discriminating predictors ,
seven predictors were selected for evaluation of their discriminating ability by using the roc analysis [ table 3 ] .
for the diagnosis of intestinal bd , genital ulcers and skin lesions had a higher area under the roc curve ( auc ) ( 0.900 and 0.853 , respectively ) with high specificity ( 94.3% and 93.4% , respectively ) .
circumferential ulcers had a high specificity ( 92.5% ) , but very low sensitivity ( 28.9% ) .
the classification algorithm composed of seven predictors had the highest auc of 0.987 , and high sensitivity ( 94.3% ) and specificity ( 97.2% ) .
discriminating potential of independent factors for the diagnosis of intestinal bd * the sensitivity and specificity were obtained with the conventional cut - off value of 0.5 .
auc : area under the receiver operator characteristic curve ; bd : behet s disease .
table 1 shows the differences in demographics and clinical features between intestinal bd patients and cd patients . there were a higher prevalence of females and a slightly earlier onset in intestinal bd patients compared to cd patients ( p = 0.010 and 0.136 , respectively ) .
there was no significant difference in the duration from the onset of gastrointestinal symptoms to diagnosis between two groups ( p = 0.738 ) .
comparison of the demographic and clinical manifestations between intestinal bd and cd bd : behet s disease ; cd : crohn s disease ; sd : standard deviation .
although the involvement of both the ileum and colon was most common in both intestinal bd patients ( 91.4% ) and cd patients ( 82.1% ) , there was still a significant difference in the disease distribution between two groups ( p = 0.005 ) .
there was an increased tendency for intestinal bd patients to have involvement of the upper gastrointestinal tract ( 17.1% ) compared to cd patients ( 5.7% ) ( p = 0.073 ) .
the most frequent gastrointestinal symptom of both diseases was abdominal pain ( p = 0.517 ) .
massive gastrointestinal hemorrhage and fever were more frequent in intestinal bd patients ( p = 0.022 and 0.048 , respectively ) , while diarrhea , intestinal obstruction , and perianal lesions including perianal abscesses , fistula , and/or anal fissure were more common in cd patients ( p = 0.002 , 0.010 , and 0.027 , respectively ) .
intestinal bd , as a multisystemic disease , involved more extraintestinal symptoms compared to cd ( p = 0.001 ) . for example , genital ulcers and skin lesions were very common in intestinal bd patients , while they were rare in cd patients ( p < 0.001 ) . furthermore
based on multivariate logistic regression analysis of demographics and clinical features , diarrhea and extraintestinal manifestations were found to be two independent discriminating predictors ( p = 0.048 and 0.008 , respectively ) .
based on colonoscopy , there were significant differences in the ulcer distribution ( p < 0.001 ) , ulcer size ( p = 0.017 ) , ulcer type ( p < 0.001 ) , and ulcer number ( p = 0.014 ) in a local area between the two groups [ table 2 ] .
focal involvement , ileocecal valve deformity , solitary ulcer , large ulcers ( ulcer size > 2 cm ) , and circumferential ulcers were more common in intestinal bd patients ( p = 0.003 , 0.003 , 0.014 , 0.013 , and 0.003 , respectively ) , while segmental involvement , longitudinal ulcers , a cobblestone or nodular appearance , and pseudo - polyps were more common in cd patients ( p = 0.003 , 0.008 , 0.023 , and 0.002 , respectively ) .
there was no significant difference in the frequency of aphthous ulcers between the two groups ( p = 0.679 ) .
comparison of the colonoscopic features between intestinal intestinal bd and cd ( n ( % ) ) * ileocecal region represents terminal ileum and/or cecum .
according to multivariate logistic regression analysis of colonoscopic features , the ulcer distribution , ulcer size , ulcer type and pseudo - polyps were independent discriminating predictors ( p = 0.006 , 0.021 , 0.002 , and 0.041 , respectively ) .
the histology of mucosa biopsies in 11.4% cd patients revealed noncaseating epithelioid granulomas . neither the appearance of vasculitis nor granulomas was found in the mucosa biopsies of intestinal bd patients .
among the independent discriminating predictors , seven predictors were selected for evaluation of their discriminating ability by using the roc analysis [ table 3 ] . for the diagnosis of intestinal bd , genital ulcers and skin lesions had a higher area under the roc curve ( auc ) ( 0.900 and 0.853 , respectively ) with high specificity ( 94.3% and 93.4% , respectively ) .
circumferential ulcers had a high specificity ( 92.5% ) , but very low sensitivity ( 28.9% ) .
the classification algorithm composed of seven predictors had the highest auc of 0.987 , and high sensitivity ( 94.3% ) and specificity ( 97.2% ) .
discriminating potential of independent factors for the diagnosis of intestinal bd * the sensitivity and specificity were obtained with the conventional cut - off value of 0.5 .
auc : area under the receiver operator characteristic curve ; bd : behet s disease .
the differential diagnosis of intestinal bd and cd is challenging due to their similarities in mucocutaneous and gastrointestinal manifestations .
both diseases have variable epidemiological and clinical manifestations among different ethnicities . as the first comparative study in chinese intestinal bd and cd patients , this study revealed that diarrhea , extraintestinal systemic manifestations , and certain colonoscopic features including ulcer distribution , ulcer type , ulcer size , and pseudo - polyps were independent discriminating predictors .
consistent with other studies , this study showed the following similarities between two diseases : ( 1 ) both diseases had a young age of onset ( 2040 years ) and long disease duration from symptom onset to diagnosis .
( 2 ) the ileocecal region was the most commonly involved site , and multiple gastrointestinal tract sites could be involved .
( 3 ) abdominal pain was the most common gastrointestinal symptom , and severe complications including perforation , fistulae , and massive gastrointestinal bleeding were not rare in either disease .
( 4 ) both diseases could have extraintestinal systemic manifestations such as recurrent oral ulcers , musculoskeletal lesions , and skin lesions . beyond the similarities ,
intestinal bd patients were more likely to be female while cd patients were more likely to be male .
more upper gastrointestinal tract involvement occurred in intestinal bd patients while more perianal lesions occurred in cd patients .
gastrointestinal bleeding , especially massive hemorrhage , and fever were more common in intestinal bd , while diarrhea and intestinal obstruction were more common in cd .
extraintestinal systemic manifestations were the most powerful discriminating factors between two diseases , especially genital ulcers and skin lesions
. the diagnostic value of endoscopic features for both diseases has always been promising . in 2009 , kim et al .
compared the colonoscopic findings between 115 intestinal bd patients and 135 cd patients , and found that ulcer shape , ulcer distribution , ulcer number , absence of aphthous lesions , and a cobblestone appearance were independent discriminating predictors .
our study confirmed that there were significant differences with respect to these five predictors except the presence of aphthous lesions .
we also found that ulcer size and pseudo - polyps were two additional independent discriminating predictors . in the korean study , aphthous lesions occurred in 74.7% of cd patients , and in 11.3% of intestinal bd patients , while aphthous ulcers were rare in the intestinal bd and cd patients from our study .
aphthous ulcers may be the earliest lesions which then become larger and deeper following the disease progression .
all patients in our cohort were hospitalized due to advanced and complicated illness , so these early stage aphthous ulcers might have been missed .
korman et al . found that the prevalence of aphthous ulcers in bd patients was 83.3% based on enteroclysis , which is contrary to the results of the former study and our findings based on colonoscopy .
kim et al . also developed a simple decision tree by classification and regression tree analysis which was based on the ulcer shape and distribution .
this was validated in the korean cohort and proved to have high sensitivity ( 94.3% ) and specificity ( 90.0% ) . however , when this same decision tree was applied to our cohort , the sensitivity for the diagnosis of intestinal bd was 85.7% , while the specificity was only 60.3% .
the difference in the diagnostic accuracy of the decision tree may be due to these factors : ( 1 ) different definitions of ulcer type . in our study
, we defined a circumferential ulcer as a deep round ulcer with a discrete margin , but in the korean study round ulcers were only defined by shape .
the prevalence of focal involvement in cd patients was only 23.1% in the korean study , while it was 47.2% in our study .
as mentioned above , the patients in our cohort had advanced disease , which could be indicated by the high incidence of operation ( 58% ) over the course of their follow - ups . ( 3 ) in our study , circumferential ulcers and longitudinal ulcers were both present in 5 patients , which made it difficult to categorize them according to the decision tree . until now
, no worldwide consensus has been established for the diagnosis of intestinal bd . in 2009 , kim et al . developed a novel set of diagnostic criteria for intestinal bd and validated it in korean patients with ileocolonic ulcers .
the criteria have two aspects : extraintestinal systemic manifestations and  typical ulcers  upon colonoscopy , defined as < 5 deep ulcers with an oval shape , discrete borders and locations in the ileocecal area . in their cohort ,
86.2% intestinal bd patients had  typical ulcers ,  compared to only 1.5% of nonintestinal bd patients . using the criteria , the overall sensitivity was 98.6% , the specificity was 83% , and the accuracy was 91.1% . according to the criteria , 35 intestinal bd patients in our study would be classified as definite intestinal bd ( 30 ) or suspected intestinal bd ( 5 ) , while 106 cd patients would be classified as probable intestinal bd ( 2 ) , suspected intestinal bd ( 33 ) , or nonintestinal bd ( 71 ) .
thus , when we apply these criteria for the differential diagnosis of patients with ileocecal ulcers , the suspected intestinal bd patients should be carefully examined by regular check - ups .
first , since this study was a retrospective cohort study in a single center , and all patients enrolled were hospitalized , there was definite selection bias .
intestinal bd is still rare , and only patients with ulcerative lesions based on colonoscopy and without any history of operation on the gastrointestinal tract except appendectomy were enrolled in the study , which also contributed to the selection biases .
third , intestinal bd and cd patients were most often diagnosed and treated by rheumatologists and gastroenterologists , respectively . due to their different perspectives , some valuable information might have been missed .
for example , a gastroenterologist might have paid more attention to the gastrointestinal manifestations and ignored extraintestinal manifestations . further large prospective multi - center or population - based studies
are needed to explore the differential markers between these two diseases and develop a worldwide consensus on the diagnosis of intestinal bd .
extraintestinal systemic manifestations and some colonoscopic features including focal involvement , large ulcers , and circumferential ulcers favored the diagnosis of intestinal bd . on the contrary , diarrhea and the endoscopic features , longitudinal ulcers , and pseudo - polyps favored the diagnosis of cd .
 background : the distinction between intestinal behet 's disease ( bd ) and crohn 's disease ( cd ) is always challenging due to many overlapping clinical features . 
 we conducted a retrospective study to reveal valuable strategies for the differential diagnosis between intestinal bd and cd in chinese patients based on their clinical and colonoscopic features.methods:thirty-five intestinal bd patients and 106 cd patients hospitalized from january 1983 to january 2010 , who had ulcerative lesions in the terminal ileum or colon under colonoscopy and no history of gastrointestinal operation except appendectomy before admission , were enrolled . 
 univariate and multivariate logistic regression analyses were conducted to find discriminating predictors among demographic data , clinical manifestations , and colonoscopic findings.results:based on univariate analysis , massive gastrointestinal hemorrhage , fever , and extraintestinal systemic manifestations were more common in intestinal bd patients ( p = 0.022 , 0.048 and 0.001 , respectively ) , while diarrhea , intestinal obstruction , and perianal lesions were more common in cd patients ( p = 0.002 , 0.010 , and 0.027 respectively ) . based on colonoscopy , focal involvement , ileocecal valve deformity , solitary ulcers , large ulcers ( ulcer size > 2 cm ) , and circumferential ulcers were more common in intestinal bd patients ( p = 0.003 , 0.003 , 0.014 , 0,013 , and 0.003 , respectively ) , while segmental involvement , longitudinal ulcers , a cobblestone or nodular appearance , and pseudo - polyps were more common in cd patients ( p = 0.003 , 0.008 , 0.023 , and 0.002 , respectively ) . based on multivariate logistic regression analysis , diarrhea , extraintestinal manifestations , ulcer distribution , size , and type , and pseudo - polyps were independent discriminating predictors between the two groups ( p = 0.048 , 0.008 , 0.006 , 0.021 , 0.002 , and 0.041 , respectively ) . the discriminating algorithm composed of the above independent predictors had the highest area under the curve of 0.987 for distinguishing between the two diseases.conclusions:extraintestinal systemic manifestations and the characteristic colonoscopic features , such as ulcer distribution , size and type , helped to distinguish intestinal bd from cd . 
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Patients
Diagnostic criteria
Clinical and colonoscopic features
Statistical analysis
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Demographics and clinical features
Colonoscopic features
The discriminating potential of independent predictors
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