Intestin grêle: pathologies Flashcards
(30 cards)
What is Gee-Herter’s Disease?
Infantile form of celiac disease
What was described in 1936?
- Willem Karel Dicke
- Orphanage: stéatorrhée, delayed growth, malnutrition, edema (hypoalbuminemia), anemia (deficit in iron and folate), polyneuropathy (B12, vit. E), osteomalacia (Ca, vit. D)
What is stéatorrhée?
quantité anormalement élevée des graisses (lipides) dans les selles
How was celiac’s discovered?
WILLIAM K. DICKE
Experimentation in children with removing wheat from diet and replacing it with rice… symptoms go away when wheat is replaced… discovered association between Sx and eating wheat
What is the typical presentation of celiac’s in adult and children?
Chronic diarrhea > 3 months, steatorrhea, flatulence due to malabsorption, weight loss, delayed growth, fatigue, edema
Physical examination: dermatite herpétiforme
Labs: anemia (deficient in B12, folate, and iron), hypoalbuminaemia (problem with absorbing not liver)
What is dermatite herpétiforme?
intensely itchy, chronic papulovesicular eruptions, usually distributed symmetrically on extensor surfaces (buttocks, back of neck, scalp, elbows, knees, back, hairline, groin, or face)
What causes celiac?
Gluten and its derivatives (gliadine, glutenine) are not digested/absorbed properly
- Gliadine is absorbed and degraded by tissue transglutaminase (enterocytes)
What is the pathophysiology of celiac’s?
Patients with HLA DQ2, DQ8
- Auto immune rxn to degradation products of gliadine which leads to the formation of anti-gliadine antibodies and anti-transglutaminase antibodies
- Intolerance to gluten (gliadine)
What is the prevalence of celiac’s disease?
Currently increasing in pop. due to better testing (0.05% —> 1% of population)
How is celiac’s dx?
S/S: anemia, diarrhea, malnutrition
Blood test: test for anti-transglutaminase + IgA serum /anti-DGP (not done in clinic)
Biopsy: duodenal biopsy (villosity atrophy)… redo after gluten is eliminated —> restored villosities
What does celiac’s look like… histologically?
Atrophy of villosities w/ aug. in immune cells (T-cells)
No “bordure en brosse” —> cells constantly multiplying and being replaced so no time for BenB to form
How is celiac’s treated?
Diet w/o gluten: villosity (seigle, avoine, blé, orge) —> (rye, oats, wheat, barley)
What’s ok?: rice, corn, soya
Take vitamins to replenish deficit due to diarrhea until replenished
What is non-celiac gluten intolerance?
Not really known… but diet w/o gluten improves symptoms
What are some complications of celiac’s?
Increased risk for neoplasms… (not really sure anymore):
- Lymphoma due to inc. T-cell presence
-
Cancer épidermoïde de l’oesophage
- people with untreated celiac disease have a higher risk, but this risk decreases with time after diagnosis, probably due to the adoption of a gluten-free diet, which seems to have a protective role against development of malignancy in people with celiac diseas
- Adenocarcinoma of the small intestine… ??? not really sure but used to think it was due to increased multiplication/regeneration of cells —> inc. chances of mutations
Other: ulcerations, perforation, stricture (abnormal narrowing of passage)
Are tumours in the small intestine common?
NO… quite rare (benign and malignant)
What are the different kinds of tumours that can be found in the small intestine? BENIGN VS MALIGNANT (9)
What are the 4 most frequent malignant tumours in the small intestine?
Adenocarcinoma (1/2)
Carcinoid tumours (1/4)
Lymphoma (15%)
Sarcomas (including GIST) (10%)
What are some clinical manifestations of intestinal tumours (small)? (7)
Douleurs abdominales crampiformes
Perte de poids
Distension abdominale (tympanique)… bloque à l’ilion terminale
Obstruction intestinale: sténose ou invagivation grêle-grêle
Fatigue et dyspnée: anémie
Hémorragie aiguë
Masse abdominale (not palpable)
What is invagination grêle-grêle?
Intussusception: serious condition in which part of the intestine slides into an adjacent part of the intestine due to peristalsis
How is cancer of the small intestine diagnosed?
Gastroscopy + colonoscopy —> N/A
Transit de grêle (contraste ingéré: image fluoroscopy)
Tomodensitométrie (contraste ingéré: image fixe)
Entéro-tomodensitométrie (contraste infusé dans le duodénum par tube)
Endoscopie du grêle: peu disponible
Capsule endoscopique: $$ (vidéocapsule)
How is cancer in the small intestines treated?
Benign: surgery
Malignant:
- Surgery
- Radiotherapy and chemo not used much
- Adenocarcinoma (most frequent) —> bad prognostic (5 year survival rate of 25%)
What are carcinoid tumours?
- Originate from neuroendocrine cells (Cellules G —> gastrinoma)
- 0.5% of all tumours
- Everyone in the GI tract —> lungs, stomach, pancreas, small intestine, and colon)
- Ileum is most frequent
- Capacity to secrete bioactive amines (vasopaptides)
- Portal vein drainage: vasopeptides degraded by the liver
- Degradation products: 5-HIAA (inactive) —> excreted in urine
What are some symptoms of carcinoid tumours?
Asymptomatic
Incomfort/abdominal pain/vague symptomatic
Obstruction: tumour, invagination, mesenteric reactional fibrosis
Anemia/bleeding (acute)
Syndrome carcinoïde (only in 10% of cases)
What is syndrome carcinoïde?
Tumeur carcinoïde du grêle —> cause syndrome seulement si métastase(s) hépatique(s)
Ou si tumeur carcinoïde primaire est extra-digestive (lungs, ovaries —> systemic drainage)
What causes syndrome carcinoïde?
Secretion of bioactive products by tumour: serotonin acts on smooth muscle to cause diarrhea, colic, and malabsorption. Histamine and bradykinin, through their vasodilator effects, cause flushing.
