ULCERATIVE LESIONS OF INTESTINE

Dr. Roopa UrsAssistant professor

Histology of duodenum

Histology of jejunum

Histology of ileum

Payer’s patches

Electron microscopy- villi

Colonic mucosa

What are the ulcerative lesions?• Duodenal Ulcer• Amoebic ulcer• Typhoid ulcer• Tuberculous ulcer• Bacillary dysentry

• Viral-CMV-AIDS

• IBD-Ulcerative colitis-Crohns disease

• Carcinoma

• OthersGVHD- Graft Verses Host DiseaseHyperplastic tuberculosisBehcet’s syndrome

Duodenal Peptic Ulcers • Young men

• Causes- H.pylori Stress, spicy food NSAID- aspirin Cigarette smoking Heavy drinking Chemotherapy/Radiation therapy • Symptoms- Burning sensation, bloating, hunger,

• Pathogenesis Alteration in the balance b/w acid production

and mucosal defence barrier resulting in damage to the lining epithelium.

GROSS

Chronic duodenal ulcer

Proximal duodenum few centimeters of pyloric valve n involve anterior duodenal valveSolitary<0.3cmShallow0.6cm- deeper ulcersRound, oval, sharply punched out defectMucosal margin may overhang the base slightlyBase is smooth and clean as a result of peptic digestion of exudateBlood vessels+

MICROSCOPY

• Active ulcers the base may have thin layer of fibrinoid debris underlaid by neutrophilic inflammatory infiltrate.

• Beneath this active granulation tissue infiltrated with mononuclear leucocyte and a fibrous or collagenous scar forms the ulcer base

• Vessel wall thickened, occasionally thrombosed • Scarring – entire thickness, pucker surrounding

mucosa

MICROSCOPY

Low-power cross-section view of a duodenal ulcer crater with an acute inflammatory exudate in the base

Complications

Bleeding

Perforation

Cancer

AMOEBIC ULCER• Amoebiasis is caused by Entamoeba histolytica (ameba)• Dysentery-causing protozoan parasite spread by fecal-

oral transmission.

• Pathogenesis. -E. histolytica cysts, which have a chitin wall and four nuclei, are the infectious form because they are resistant to gastric acid.

-Cysts release trophozoites, the ameboid forms, which reproduce under anaerobic conditions without harming the host.

Morphology of amoebic ulcer

• Cecum and ascending colon, followed by the sigmoid colon, rectum, and appendix.

Discrete areas of ulceration covered by exudate, with normal intervening mucosa

• MICROSCOPY- Ulcer shows inflammatory infiltrates and granulation tissues.

• Trophozoites of amoebae can mimic the appearance of macrophages because of their comparable size and large number of vacuoles.

• Amoebic ulcer-fan out laterally to create a flask-shaped ulcer with a narrow neck and broad base.

• Erythrophagocytosis.

• Special stains: - PAS- positive. - Iron Hematoxylin -positive.

Entamoeba histolytica

COMPLICATIONS:

• Parasites may penetrate splanchnic vessels and embolize to the liver to produce amoebic liver abcesses.

• Amebic liver abscesses, which can exceed 10 cm in diameter, have a scant inflammatory reaction at their margins and a shaggy fibrin lining.

• Amebae may also spread via the bloodstream into the kidneys and brain.

SALMONELLOSIS- Typhoid ulcer

Causative agent- S. typhimureum.S. paratyphi.

• PATHOGENESIS:Salmonella possess virulence genes that encode a type III secretion system capable of transferring bacterial proteins into enterocytes.

The transferred proteins activate host cell Rho GTPases, bacterial uptake that allow bacterial growth within phagosomes.

In addition, flagellin, the core protein of bacterial flagellae, activates TLR5 on host cells and increases the local inflammatory response

GROSS• Usually affects ileum and colon.

• It present as longitudinal ulcer over the peyers patches.

Typhoid ulcer

MICROSCOPY

- Neutrophils accumulate within the superficial LP & macrophages containing bacteria, RBCs, nuclear debris mix with lymphocytes n plasma cells in LP.

- Mucosal shedding create oval longitudinal ulcers

- Blunting of villi- Mucosal congestion and edema

CLINICAL FEATURES

Anorexia, abdominal pain, bloating, nausea, vomiting, and bloody diarrhea.

Blood cultures are positive in >90% of affected individuals during the febrile phase.

In chronic phase- Rose spots, small erythematous maculopapular lesions, are seen on the chest and abdomen.

• Extra-intestinal complications including encephalopathy, meningitis, seizures, endocarditis, myocarditis, pneumonia, cholecystitis and Salmonella osteomyelitis.

TUBERCULAR ULCER• Causative agent- Mycobacterium tuberculosis

• Mostly affects the ileum or ileocaecal junction

• May or may not be associated with TB elsewhere

• Intestinal tuberculosis contracted by the drinking of contaminated milk.

• In countries where milk is pasteurized, intestinal TB is caused by the swallowing of coughed-up infective material in patients with advanced pulmonary disease

MORPHOLOGY OF TUBERCULAR ULCER

GROSS-Transverse ulcer in the direction of lymphatics

-muliple and circumferential

- Ulcer leads to fibrosis which cause stenosis and obstruction

MICROSCOPY

• CASEATING GRANULOMA- Shows central caseous necrosis

surrounded by granuloma- Granuloma composed of epitheloid

cells, langhans giant cells and lymphocytes.- AFB/ ZN Stain positivity.

TB- microscopy

BACILLARY DYSENTRY- Clostridium toxin

• It affects colon

• CAP LESION- Small yellow white plaque like lesions

• PSUEDOMEMBRANE FORMATION- fibrino purulent necrotic debris

GROSS

MICROSCOPY

Epithelium- denuded

Superficial LP- dense neutrophilic infiltrate, occasional fibrin thrombi within capillaries

Damaged crypts are distended by mucopurulent exudate forming Mushroom/ Volcano fibrinous exudates.

BACILLARY DYSENTRY- Campylobacter jejuni

• It affects jejunum to ileum.

• Muiltiple superficial ulcer over the mucosa

• Microscopy -Cryptitis -Crypt abscess

-Congestion-Ulceration

BACILLARY DYSENTRY- Campylobacter jejuni

Crypt abscess

ULCERATIVE COLITIS• It is a inflammatory bowel disease.

• It usually affects the rectosigmoid junction.

• Gross:- Irregular multiple ulcer-Multiple pseudopolyp-Continuos lesion with retrograde

progression

UC- Inflammatory polyp

• Microscopy :-Mucosal edema and hyperemia.-Crypt distortion-Crypt abscess-Mucosal depletion

UC- crypt abscess

CROHN’S DISEASE• It is another inflammatory bowel disease.

• Affects ileum and proximal colon.

• Gross:-Long serpentine linear ulcer.-Cobblestone appearance.-Skip lesions.-Fissure and fistula.

• Microscopy shows non-caseating granuloma.

CROHNS DISEASE- Non caseating granuloma

CROHNS DISEASE ULCERATIVE COLITIS

CARCINOMATOUS ULCER• Commonly affects the rectosigmoid area and

affects any part of colon.

• Gross:- Single, firm, everted, large cauliflower

shaped ulcer.

• Microscopy:-Shows malignant glands infiltrating to

deep muscle area.

Carcinoma- gross

Carcinoma- microscopy

GRAFT VERSUS HOST DISEASE• Usually occurs after bone marrow

transplantation and rarely occurs following blood transfusion

• Symptoms include fever, skin rash, hepatitis, bone marrow suppression and the outcome is fatal.

• Pre-transfusion irradiation of all blood components containing lymphocytes will prevent GVHD

GVHD-Graft Verses Host Disease• Any where in gastrointestinal tract.

• Features :-Crypt abscesses.-Inflammatory polyp.-Fibrosis.-Chronic inflammation.

BEHCET’S SYNDROME• Affects large bowel.

• Shows multiple ulcers of various sizes, shape and depth.

• Microscopy shows lymphocytic vasculitis of submucosal veins.