- The document discusses the interpretation of endoscopic biopsies, including technical aspects, common findings, and pitfalls. It covers biopsies of the esophagus, stomach, and small intestine. - Key points include descriptions of normal histology, as well as abnormalities seen in conditions like esophagitis, gastritis, celiac disease, infections, and more. Specific features of various diseases are outlined at both low and high power. - Accurate biopsy interpretation requires correlation of histological findings with clinical information and endoscopic features. Multiple biopsy samples are often needed to make a definitive diagnosis.

1. Interpretation of the endoscopic
biopsy
GUIDED BY- Brig Vibha Dutta, SM
Presented by Maj Ganesh Parajuli

2. OVERVIEW
•
•
•
•
•
Introduction
Technical aspects
Interpretation
Pitfalls
Conclusion

3. Introduction
• Endoscopy : Examination of
internal body cavities using a
specialized medical instrument
called an endoscope

4. Introduction (contd….)
• Fibrooptic endoscopy and biopsy
– diagnostic procedure in investigation GI disorder
• The first gastroscope:
George Wolf in 1911
• Semiflexible gastroscope:
1930
• Harold designed fibroscope:
early 1950
• Newer technologies: chromoendoscopy, capsule endoscopy
endoscopic ultrasound

5. General features of GI biopsy
interpretation
• GI tract: limited repertoire of response to host injuries
• Diagnoses requires correlation with clinical information
• Normal biopsies may be obtained from symptomatic patients
• Inflammatory cells are a normal constituent of lamina propia

6. Overview comments on the
GI tract
4 layers of tissue surround the
lumen of the GIT
Mucosa
 epithelium – protective, absorbtive & secretory
lamina propria – thin loose CT
 muscularis mucosa – slim double layer of
smooth muscle
Submucosa
Muscularis propria
Skeletal muscle at beginning
& smooth muscle at the end
(inner circular; outer longitudinal
layer) from lower esophagus to
rectum
Serosa
(viseral peritoneum)

7. The major uses of mucosal
biopsy includes:
i.
Diagnosis : either specific or in the form of an injury pattern
or stage
ii. Determination of the extent or severity of lesions
iii. Monitoring of the clinical course of disease states with
particular reference to effects of therapy
iv. Detection of complication

8. Assessing any biopsy from GI tract
Clinical pathological correlation is essential for diagnosisThe following clinical data should be provided :
1. Age, race and sex of the patient
2. Sign and symptoms, site of biopsy, endoscopic and
radiological finding
3. History of taking drugs or alcohol
4. Medical and surgical history

9. Technical aspects
• The grasp biopsy specimens obtained at flexible endoscopy
typically consists only of the mucosa
Regions with thicker mucosa contain only superficial portion
• Suction or aspiration-type biopsy more fruitful when a larger
sample or more exact location is required
• Choice of fixative is usually not critical though Bouin’s may
interfere with staining of the granules of Paneth cells
• Multiple sections to improve the chance of detecting any
focal or subtle changes

10. • For routine analysis at least 3 levels of biopsy specimen, each
with 5 or more sections
• When focal lesion not obtained, additional levels should be
require
• Cytologic preparations useful diagnostic adjunct

11. Ideal Mucosal Biopsy
•
At least 3 pieces of full thickness mucosa
3 mm in length
• Mucosal fragments well oriented at time of embedding
crypt:villous ratio can accurately evaluated

12. Abnormal esophageal Mucosal Biopsy
Abnormal esophageal
mucosa
Non neoplastic
Infections
ViralHerpes simplex
CMV
FungalCandida
Others
Corrosive
- lye
Reflux
Neoplastic
Benign
Squamous papilloma
Malignant
Squamous cell carcinoma
Adenocarcinoma

13. Esophagitis
The 4 most common types of esophagitis:
1. Pill esophagitis
– Spectrum of injury by the ingestion of drugs
– Common site anatomical narrowing
– Ulcer ,granulation tissue ,polarizable foreign material and
multinucleted gaint cells
2. Infectious:
– HSV, CMV (BMT, solid organ transplant)
– Candidal (HIV, thrush associated)
Yeast and pseudohypae seen in necroinflammatory
background

14. 3. Eosinonophilic esophagitis: frequently seen in childern
Endoscopic finding –stricture , rings corrugation,furrows and
granularity
Mucosal edema ,basal cell hyperplasia with eosinophil
infiltration of sq mucosa >20 eosinophil per high
field

15. 4.Reflux disease
• GERD the costliest GI disorder & the most common physician
diagnosis GI disorder in outpatient clinic visit
• GERD caused by reflux of gastric contents into esophagus
Reflux of gastric acid and pepsin
• Reflux of alkaline bile & pancreatic secretion moving from
duodenum
stomach
esophagus recognized as a
contributing factor to esophageal injury in GERD

16. • ‘Reflux esophagitis ‘ an example of ‘itis ‘ lack prominent
component of inflammation
• The pathology reflects injury to sq epithelium followed by
attempts of the epithelium to regenerate
• Mild features of cellular injuryballoon cells
vascular lakes, mild inflammation and scattered eosinophils

17. REFLUX/GERD

18. Fairly reproducible criteria established by Fiocca et al as
abnormal and associated with clinical reflux –
i. Thickened basal layer(>15%) or 5 to 6 layers
ii. Increased papillary length (>50%) of the squamous thickness
iii. Intraepithelial eosinophil ,neutrophil (>1to 2 cells /40x field)
iv. Intraepithelial mononuclear cells.(>10/40x field)
v. Dilated /widened inter cellular spaces(which may appear as
bubbles or ladders.

19. BARRETT’S ESOPHAGUS
• Defined as intestinal metaplasia of a normally SQUAMOUS
esophageal mucosa.
• The presence of GOBLET CELLS in the esophageal mucosa is
DIAGNOSTIC.
• SINGLE most common RISK FACTOR for esophageal
adenocarcinoma
• 10% of GERD patients get it
• “BREACHED” G-E junction

20. BARRETT’S ESOPHAGUS

22. Gastritis
• No widely accepted classification of gastritis
• Updated Sydney System
Published in 1997
• Attempted to combine topographical, morphological and
etiological information
• Largely unused bec of inadequate sampling & clinical
information ,poor endoscopic & histologic correlation and
ethic and geographic variation of the disease
Operative Link for Gastritis Assessment (OLGA) staging system:
Based on extent and severity of atrophic gastritis and provide
relevant clinical information regarding the gastric cancer risk.
However, atrophic gastritis is a difficult histopathological
diagnosis of which the interobserver agreement is low.

23. H pylori associated gastritis
• Helicobacter pylori (H pylori) common bacterium that is present in
millions of people worldwide
• found in mucous lining of stomach. It is known to be responsible for
60% to 80% of gastric ulcers and 70% to 90% of duodenal ulcers
• The recognition of an association between this bacterium and
peptic ulcer disease by Barry Marshall and John R. Warren, in
1983, and they were awarded the Nobel prize in 2005
• Another varient called H. heilmannii (less than 1% isolates)
• Like H pylori it produces antral predominant gastritis ,less sev, than
H. pylori gastritis

24. • Histologically shows organisms within the surface mucus
layer and foveolar epithelium
• Abundant, lymphoplasmacytic , chronic inflammation of
lamina propria
• Presence of lymphoid follicles (MALT) almost always
indicative of infection

25. A simplified pathology report of gastritis
include the following parameters:
a. Type of mucosa
b. Grade of lymphoplasmacytic infiltration (4 M)
c.
Presence or absence of active inflammation with degree of
activity(if present)
d. Extent of intestional metaplasia or atrophy(if present)
e. Presence or absence of H pylori microorganism

26. Normal histology
• Finger-like villi
• C:V ratio (assessed where 4
well-oriented crypts and villi
are seen)
• Normal C:V ratio 1:3 or
more
• C:V ratio lower in children
and elderly
• C:V ratio usually uniform in
a biopsy

27. Evaluation of small intestinal mucosal
biopsy
Low power
• adequacy of biopsy
• crypt villous architecture
• degree of inflammation
High power
• Specific features in lumen, epithelium and lamina
propria

28. Indications for biopsy:
• Evaluation for patients with malabsorption
• Investigation for patients with iron deficiency anemia,
diarrhoea particularly in whom infections is suspected with
AIDS
• Diagnosis of neoplasia
• Confirmation of ulceration induced by NSAID or in cases of
bleeding from unknown site.

29. Abnormal Small Intestinal Mucosal Biopsy
Abnormal small intestinal
mucosa
Nonspecific changes
Specific changes
Celiac disease
Tropical sprue
Bacterial overgrowth
Epithelial
Cow’s milk allergy
Chronic renal failure
B12, folate, iron, zinc def
Autoimmune enteropathy
Infections
Others
Drugs
Viral
Parasitic
Bacterial
Lumen
parasites
Lamina propria
Infections
Lymphocytic
Viral
Abetalipoprot.
Parasitic
Microvillous inc Fungal
GVHD
AIDS enteropathyl
Inflammatory
lBD
Granulomatous
Collagenous
Eosinophilic
Immunodeficiency
Autoimmune enterop
Metabolic
Amyloidosis
Storage
disorders
Neoplasms
Benign polyps
Adenocarcinomas
Endocrine
Lymphomas
GISTs
Waldenstrom’s

30. Spectrum of Nonspecific inflammatory changes
in the small intestinal mucosa
Architecture
• Crypt hyperplasia
• Crypt hyperplasia with villous atrophy
• Villous atrophy with crypt hypoplasia (rare)
• Branching, broadening and fusion of villi (mild cases)
Epithelium
• Epithelial damage: flattening, nuclear irregularity, loss of polarity,
vacuolization, basophilia
• Increased intraepithelial lymphocytes
• Increased apoptosis
• Macrocytosis of epithelial cells
Lamina propria
• Chronic inflammation
• Acute inflammation

31. Varying degrees of change
mild
mod
sev

32. Celiac disease
Macroscopic features
• On endoscopy the mucosa appear flattened and scalloped if
there is significant villous atrophy
Microscopic features
• Microscopic changes most severe in duodenum and decrease
in severity distally
• 4 small intestinal biopsies are required for absolute diagnostic
confidence (Pais et el, Gastroint Endosc 2008);
• May be patchy
• Changes decrease with gluten withdrawal and recur when
gluten is re-introduced

33. Celiac disease : Spectrum of changes
Marsh’s diagnostic criteria
•
0 – preinfiltrative: Dermatitis herpetiformis; no mucosal change
•
I More than 40 intraepithelial lymphocytes per 100 epithelial cells –
infiltrative
•
II. Crypt hyperplasia with increased intraepithelial lymphocytes –
infiltrative type 2
•
•
•
•
III. Crypt hyperplasia with increased intraepithelial lymphocytes and
villous atrophy
IIIa Mild villous atrophy
IIIb Moderate villous atrophy
IIIc Severe villous atrophy
•
IV Crypt hypoplasia with villous atrophy

35. Tropical sprue
• Chronic malabsorptive syndrome seen in residents and
visitors to tropical countries
• Etiology related to chronic infections and bacterial
overgrowth
• Entire small intestine from duodenum to terminal ileum may
be involved
• Villous atrophy, crypt hyperplasia, inflammation and
increased IELs
• Often responds to broad spectrum antibiotics like tetracycline

36. Cow’s milk protein allergy
• Temporary condition affecting young infants presented with
malabsorption & dehydration requiring parenteral nutrition
•
Bloody diarrrhoea, vomiting, abdominal pain, weight loss
• Small intestional mucosal changes similar to celiac disease
but lesser extent
• Intraepithelial eosinophils & peripheral eosinophil are more
noted with cow’s milk

37. Nutritional deficiences
Vitamin B12, protein, iron and zinc deficiency
Structural abnormalities of intestional mucosa
associated with malsorption
• B12: villous blunting, macrocytosis, decreased mitoses
• Protein deficiency
• Zinc deficiency

38. AIDS enteropathy
•
Individuals infected with HIV with chronic diarrhoea have
opportunistic infections or diffuse small intestional mucosal
alterations in the absence of pathogens
• Duodenal biopsies may shows crypt hyperplasia and partial
villous atrophy, increased intraepithelial lymphocytes and
infiltration of the lamina propria by plasma cells and
lymphocytes
• Crypts shows evidence of increase apoptotic activity

39. Specific changes in Small intestinal
biopsies
Lumen

40. Giardia Lamblia

42. Infections
Giardiasis
•
Most common parasitic infection
•
Presence of trophozoites in fecal and duodenal biopsy specimen confirm
giardia infection
•
Duodenum (more than 80%) followed by jejunum and ileum, rarely the
stomach and colon
•
The mucosa is normal shows minimal changes in majority of cases with
mild villous atrophy, crypt hyperplasia , loss of normal brush border
shorting of villous epithelium and increase intraepithelial lymphocytes
•
The parasite found in lumen close to the surface of villous epithelium

43. Specific changes in Small intestinal
biopsies
Epithelium

44. Lymphocytic enteritis

45. Increased intraepithelial lymphocytes
•
•
•
Definition:
> 30 or 40/100 villous epithelial
cells
Or more than 5 per 20 villous tip
epithelial cells
•
Should be diffuse
•
Counting should not be done
over a lymphoid follicle
Causes
• Infections
• H.pylori infection
• Tropical sprue
• Celiac sprue
• Refractory sprue
• Protein intolerance
• NSAIDs
• Bacterial overgrowth
• IBD
• Lymphocytic enteritis
• AIDS, hypogammaglobulinemia
• Collagen vascular disease

46. Acute GVHD
Endoscopic findings
• Normal mucosa, erythema, ulcers and sloughing
Histologic features
• Single cell apoptosis in crypts
• Villous blunting
• Loss of crypts
• D/D: CMV infection; chemoradiation-induced damage

48. Chronic GVHD

49. Epithelial infections
Viral – nonspecific changes except CMV
Bacterial – Enteropathogenic E.coli may form colonies on the
brush border
Parasitic • Microspora – genera Encephalitozoon, Enterocytozoon
• Isospora
• Cryptosporidium
• Cyclospora

50. Cryptosporidiosis
• Cryptosporodium parvum protozoan, highly infectious with
waterborne ,person to person
• Immunocompetent pts acute ,self limiting diarrhoea while
immunocompromised pts including AIDs chronic watery
dairrhoea
• Distribution worldwide ,endemic in developing countries,
found in >50%of AIDS

51. Cryptosporidiosis

52. Microsporidiasis
Widespread obligate intracellular parasite
Opportunistic infection in immunosuppressed organ transplant patents
and those with AIDS
The infection includes :
Enterocytozoon bieneusi &
Encephalitozoon intestinalis
Histological features :
In small bowel both causes a partial villous atrophy ,mild crypt hyperplasia
with short blunt villi and mild increase in lymphocytes ,plasma cells &
eosinophil in the lamina propria

53. Microsporidiosis
Entercytozoon bieneusi
Encephalitozoon
intestinalis

54. Specific changes in Small intestinal
biopsies
Lamina propria

55. Specific changes in the lamina propria
Infections
Vascular
IBD
Others
•
•
•
•
•
Parasitic: Isospora
Viral: CMV
Bacterial: TB, MAI, Whipple’s, yersinia
Fungal: Histoplasma, cryptococcus
Crohn’s
Allergic
•
•
Eosinophilic enteritis
Lymphocytic/collagenous enteritis
Immune
•
Immunodeficiency syndromes
•
•
•
•
•
•
Radiation enteritis
Vasculitis
Ischemia
Portal hypertension
Amyloidosis
Lymphoma

56. CMV
Macroscopic
• Patchy erythema, edema, aphthous and deep penetrating ulcers
Microscopic
• Usually endothelial cells and other stromal cells deep in the base of ulcers
and other sites; rarely epithelial
•
less inflammation in immunocompromised individuals
•
Atypical inclusions: smudged nuclei
Other diagnostic tests: immunohistochemistry and PCR

57. Histoplasmosis
• Macroscopic:
• Nodular or ulcerating lesions in ileum
• Microscopic:
• Granulomas
• Fungal bodies in the cytoplasm of histiocytes; small oval yeast
forms with buds at the pointed ends

58. Mycobacterium Avium Complex
•
Commonly affects small intestine (duodenum most frequent) and colon of
immunocompromised individuals (AIDS with CD4 counts <60/mm 3
•
On endoscopy: coarse granularity, edema, erythema, yellowish streaks or
ulcers
•
•
On histology –
immunocompetent individuals show necrotizing (up to 30%, small foci) or
nonnecrotizing granulomatous inflammation;
immunodeficient individuals : diffuse infiltrates of histiocytes with foamy
or granular cytoplasm and minimal other inflammatory cells
Regional lymph nodes enlarged with similar cells
•
•
•
AFB and PAS positive (fibrillary appearance versus granular appearance of
Whipple’s)
•
EM: intact bacteria

59. • Mycobacterium
Avium Complex
• Ziehl Neelsen

60. Eosinophilic enteritis
•
Often associated with peripheral eosinophilia (75%) and allergic disorders
•
Eosinophilia may be confined to the mucosa or involve the muscle coat or
serosa
•
May present with hemorrhage, chronic diarrhea, abdominal pain,
malabsorption, protein losing enteropathy, obstruction or ascites
•
D/D: parasitic infections, vaculitis, Crohn’s disease, Gluten sensitivity,
lymphomas, inflammatory fibroid polyp, magnesium, vitamin E or
selenium deficiency

61. Eosinophilic Enteritis

62. (I) IBD
• CROHN DISEASE (granulomatous colitis)
• ULCERATIVE COLITIS

63. (I) IBD
• COMMON FEATURES
– IDIOPATHIC
– DEVELOPED COUNTRIES
– COLONIC INFLAMMATION
– SIMILAR Rx
– BOTH have CANCER RISK

64. (I) IBD DIFFERENCES
• CROHN (CD)
–
–
–
–
–
–
–
–
–
TRANSMURAL, THICK WALL
NOT LIMITED to COLON
GRANULOMAS
FISTULAE COMMON
TERMINAL ILEUM OFTEN
SKIP AREAS
“CRYPT” ABSCESSES NOT COMMON
NO PSEUDOPOLYPS
MALABSORPTION
• ULCERATIVE (UC)
–
–
–
–
–
–
–
–
–
MUCOSAL, THICK MUCOSA
LIMITED to COLON
NO GRANULOMAS
FISTULAE RARE
TERMINAL ILEUM NEVER
NO SKIP AREAS
“CRYPT” ABSCESSES COMMON
PSEUDOPOLYPS
NO MALABSORPTION

65. Intestinal TB versus Crohn’s disease
Tuberculosis:
Granulomas
• Caseation
• Confluent granulomas
• Lymphoid cuff
• Granulomas larger than 400 micrometer
• 5 or more granulomas in biopsies from
one segment
• Granulomas located in the submucosa or
in granulation tissue: often with
palisaded histiocytes
• Granulomas in the ileocecal region
•
Nonspecific inflammatory changes in the
same and adjacent segments to those
with granulomatous iflammation
•
Disproportionate submucosal
inflammation
Crohn’s disease:
Granulomas
• Small (<200 micrometer)
• Discrete
• Very few / single
• Poorly organised
• Commonly located in the mucosa
• Granulomas in the rectosigmoid
• “microgranulomas”: aggregates of
histiocytes
•
Nonspecific inflammation more diffusely
distributed and not restricted to the
same segments or those adjacent to the
sites of granulomatous iflammation
•
Crypt-centric inflammation: pericryptal
granulomas and focally enhanced colitis

66. Crohn’s disease
•
•
•
•
•
Segmental, patchy and focal involvement
Distorted crypt villous architecture, Villous atrophy
Significant chronic inflammation
Increased intraepithelial lymphocytes, cryptitis, ulceration
Granulomas, microgranulomas

67. Amyloidosis
• G.I. involvement occurs in 85 to 100% cases of
systemic amyloidosis
• Commonly causes ulceration, bleeding; motility
disorders, stasis and malabsorption
• Macroscopy: fine granularity, erosions, friability,
thickening of folds

69. Take home message
 Interpretation & evaluation of GI biopsy specimen requires
clinicopathological correlation
 Good orientation of the biopsy specimen essential for
accurate histopathological assessment.
 A well-oriented biopsy specimen should have at least 4-5
consecutive elongated ,well distended villi from the base of
the tip
 The evaluation of the villous: crypt ratio, the count and
distribution of the intraepithelial lymphocytes(IELs) as well as
the evaluation of the enterocytes in the tip is critical
 Infections can be accompanied by subtle changes in the
architecture and minimal inflammation

70. References
• Biopsy Interpretation of the Gastro intestional tract mucosa ,
Elizabeth A. Montigomery & Lysandra voltaggia .2nd Edition
• Mucosal biopsy of the Gastrointestional tract,Whitehead 2nd
edition
• Morson and Dowson’s Gastrointestional Pathology,David W
Day 4th edition
• Robbins and Cortan Pathologic Basis of Disease 8th edition
• Sternberg’s Diagnostic Surgical Pathology, Stancy E.Mills 5th
editon
• Wheater’s Functional Histology, Barbara Young , Alan,James
5th edition

71. • Pathology illustrated, Robin Reid, Foina, Elaime. 7th
edition
• S serra, P A Jane. An approach to duodenal biopsies J
Clin Pathol2006;
• Harvey Goldman, Donald. Mucosal biopsy of the
esophagus ,stomach, and proximal duodenum
Human pathology
• Netter’s illustrated Human Pathology, Gerhard, L.M.
Buja.1st edition