Critical Evaluation of Critical Evaluation of colonoscopic biopsies in colonoscopic biopsies in

Crohn’s DiseaseCrohn’s Disease

Najib Haboubi MB Ch B ,D Path, FRCPathProfessor of Health Science, Liver and

Gastrointestinal and Pathology, Universities of John Moors, Liverpool and Salford, Manchester.

Crohn, Ginzburg and Crohn, Ginzburg and Oppenhiemer 1932 JAMAOppenhiemer 1932 JAMA

‘A disease of the terminal ileum, affecting mainly young adults and characterised by……

Things have changedThings have changed

Young and old All GIT ( mostly small and large intestine)

Distinction between UC and Distinction between UC and CDCD

From a single mucosal biopsy.

Not easy!

CD Classical featuresCD Classical features

Focality Rectal sparingGranulomas.Transmural inflammation

DistalDistal UCUC is mostly is mostly

accompanied by inflammatory accompanied by inflammatory lesions of the lesions of the caecumcaecum

Geboes et al Gastroenterology 1987

Patchy Patchy CoecalCoecal Inflammation Inflammation

Associated with Associated with DistalDistal UCUC: : A Prospective Endoscopic A Prospective Endoscopic

StudyStudy D’Haens,Geboes,Peeters,Baert,Ectors, Rutgeerts. Am.J.Gasroenterol. 1997

Patchiness of mucosal Patchiness of mucosal inflammation in treated inflammation in treated

UCUC

Bernstein , Shanahan , Anton , Weinstein.

Gastrointestinal Endoscopy. 1995.

Ulcerative ColitisUlcerative Colitis

Patterns of Involvement in Colorectal Biopsies and Changes With Time.

Celina Kleer and Henry Appelman

Am.J.Surg.Path.

Material and MethodMaterial and Method

41 patients with proven chronic UC.

Sequential sets of colonic biopsies.

ResultsResultsHistologically normal

appearing mucosal biopsies do occur in established cases of CUC.

This finding is enhanced with treatment with 5 ASA.

Summary Summary In In CUCCUC

Mucosa can revert to normal with or without treatment.

Skip lesions and rectal sparing .

Classical featuresClassical features

Multi focality and Rectal sparing

Granulomas. Transmural inflammation

GranulomasGranulomas

25-90% of cases (site, specimen type,no. of slides). Seen more in early disease. Younger age group Increase yield as we travel throughout the colon. Usually related to active inflammation and

ulceration/disputed! May indicate aggressive disease (Heresbach et al Gut

2005) Specific to CD only in the setting of IBD and when they

are Sarcoid type.

Non Infective Granulomas Non Infective Granulomas

Pericryptal position can be seen in UC Diversion colitis. Diverticular disease. Sarcoidosis Chronic granulomatous disease of childhood Foreign body Pericryptal in infective colitis. Vasculitis

Infective GranulomasInfective Granulomas

TBFungal infection.Viral infection.

UCUC

Classic ViewsNever patchy No granuloma

Current viewsCan be .Pericryptal

granuloma

In practiceIn practice

The distinction between UC and CD is not always easy .

Even in the hands of the experts?

How could pathologists How could pathologists improve the initial diagnosis of improve the initial diagnosis of

colitis? colitis?

Bentley et al J Clin Path 2002,55;955-960

AimAim

1. Determine the effect of a single versus multiple biopsies on the accuracy of diagnosis.

2. Study the accuracy and reproducibility of different criteria used in the diagnosis of multiple biopsies by the experts and the non experts pathologists.

MethodsMethods

13 experts and 12 non experts examined 60 well followed up cases of CD and UC , totally blinded and in 2 rounds.

Diagnoses were made initially on rectal then full colonoscopic biopsies.

Diagnosing CDDiagnosing CD

Experts Rectal 24% Full colonoscopy 64%

Non experts Rectal 12% Full colonoscopy 60%

Diagnosing UCDiagnosing UC

Experts Rectal 64% Full colonoscopy 74%

Non experts Rectal 62% Full colonoscopy 72%

ConclusionConclusion

Full colonoscopic series are more accurate in diagnosing CD and UC

No difference between the experts and the non experts in blinded biopsies

Trafford / Manchester Trafford / Manchester approachapproach

CD is by and large a clinicopathological diagnosis.

A preliminary working pattern based report with a differential diagnosis .

The final diagnosis is made in the CPC when all the data become available.

The mutual responsibility of the clinician and the pathologist

Thanks for the invitationThanks for the invitation

Number Number

Classically UCClassically UC

A mucosal disease.The histology does not come back

to normal.In Distal disease it is Never patchy

(continuous).

UCUCMucosal. May extend into the

submucosa in acute cases and ulceration.

This is not Transmural inflammation.

Is time a good Is time a good healer?healer?

UCUC

Mucosal.

Never patchy Never come back to

normal.

May extend into the submucosa.

Yes it could .Yes it could.

Diagnostic DifficultiesDiagnostic Difficulties

There is no specific histological feature that distinguishes CUC from many other colitides.

The diagnosis has to be a team responsibility .

SystemSystemPattern based provisional report

with a working differential diagnosis.

The final diagnosis is in the CPC.No place for Non Specific Colitis

Causes of DifficultyCauses of Difficulty

1.Limited morphological response of the colonic mucosa to various injuries.

2.Incomplete morphological expression of IBD.

3. Overlap of some features.4. Clinical and histological mimicry of

IBD.

Colitis with no Colitis with no distinguishing distinguishing

histological histological featuresfeatures

Despite the legitimate Despite the legitimate pressure we cannot tell pressure we cannot tell

the differencethe difference

DilemmaDilemma

Absence of a histological parameter that is invariably present in one disease and invariably absent from the other.

ResultsResults

Infective GranulomasInfective Granulomas

Campylobacter colitis.Salmonella colitis.TBYersinia

Vienna ClassificationVienna Classification

InflammatoryStricturing , non penetrating ( stenosing)Fistulating( penetrating)

Size is not every thingSize is not every thing

Accurate reportingAccurate reporting

Full clinical storey

Classical featuresClassical features

Sarcoid type granulomas.FocalDiscontinuous.Rectal sparing.

Patchiness of mucosal Patchiness of mucosal inflammation in treated inflammation in treated

UCUC

Bernstein , Shanahan , Anton , Weinstein.

Gastrointestinal Endoscopy. 1995.

ConclusionConclusion

In patients with treated UC, the finding of rectal sparing or patchiness should not necessarily indicate a change in the diagnosis to CD.

Ulcerative ColitisUlcerative Colitis

Patterns of Involvement in Colorectal Biopsies and Changes With Time.

Celina Kleer and Henry Appelman

Am.J.Surg.Path.

Material and MethodMaterial and Method

41 patients with proven chronic UC.

Sequential sets of colonic biopsies.

ResultsResultsHistologically normal

appearing mucosal biopsies do occur in established cases of Chronic UC.

This finding is enhanced with treatment with 5 ASA.

SummarySummary

Skip lesions do occur in CUC.Mucosa can revert to normal

with or without treatment.

Granuloma specific to CDGranuloma specific to CD

Well formedIsolatedAway from areas of inflammation.Basally or submucosally situated

Frequency and significance of Frequency and significance of granulomas in a cohort of granulomas in a cohort of

incidence cases of CDincidence cases of CD

Heresbach et al Gut 2005;54: 215222

AimAim

Evaluate epitheloid granulomas occurence in incident CD.

Association between epitheloid granuloma and outcome of CD

M&MM&M

188 cases of endoscopic (upper and lower) and surgical (intestinal or colonic) procedures.

Follow up for at least 5 years.

ResultsResults

Epitheloid granulomas are associated with higher rate of surgical resections.