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Small bowel. Anatomy. Small bowel 75 % of the total length of GI Length: 260 cm by living persons 5 – 7 m post mortem Parts: jejunum 2/5 length ileum 3/5 length . Anatomy. Wall of small intestine: 1. Serous layer 2. Muscular layer smooth muscle
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Anatomy Small bowel75 % of the total length ofGI Length: 260 cm by living persons 5 – 7 m post mortem Parts:jejunum 2/5 length ileum 3/5 length
Anatomy Wall of small intestine: 1. Serous layer 2. Muscular layer smooth muscle 3. Submucosa fibroelastic tissue, blood and lymphatic vessels 4. Mucosa
Microanatomy Wall of small intestine: Circular plices - Kerkring-i enlarge 3 x the surface of mucosa Villi intestinales enlarge 10 x enlarge 3 x the surface of mucosa Microvilli enlarge 30 x surface of mucosa total enlargement 900 x !! Epithelium - enterocytes - absorb cell - goblet cells – mucin production
Anatomy Blood supply: a.mesenterica superior a. pancreaticoduodenalis inferior - pancreas duodenum aa. jejunales – one arcades- jejunum aa. ileae – 2-4 arcades - ileum a. ileocolica – colon ascendens and caecum a. colica dextra – colon ascendens a. colica media – colon transversum
Physiology digestion: 1. Intraluminal phase: chymus is mixed with enzymes from enterocytes, pancreas, bile, stomach 2. Absorb phase : in the wall of bowel absorbtion of nutrients, water, minerals, vitamins 3. Transport phase
Physiology Motility: 1. Peristaltic Circular contractions in distal direction fr.= 10/min., transit time in small bowel is 1- 6 hr. • Segmental contractions: to mix the content
Mesentery - functions 1. mechanical support for bowel 2. blood supply 3. lymphatic drainage of nutrients 4. immunological barrier
Physiology Functional disorder 1. : Maldigestion – intraluminal disorder lack of bile, stomach acid, or pancreatic intestinal juice Malabsorbtion – disorder in the phase of absorbtion or transport
Physiology Other functional disorders 2. : Diarrhea ( osmotic, infection, ) Blind sac sy ( stasis of enteral content in a blind sac, what leads to bacterial contamination and deconjugation a of bile acids - diarrhea) Short bowel sy ( after extent resections, leads to depletion of water, minerals, nutrients, vitamins) requires parenteral nutrition
Diagnostics specific enteroclysis- „small bowel enema“ study enteroscopy - double balloon - push - on table - capsule
Non specific Laboratory X-ray Ultrasound CT MRI Gastroscopy Colonoscopy AG, scintigraphy- bleeding
Meckel´s diverticulum remnant of omphaloenteteric duct, which did not obliterate Pathology : 1-2%, situated on the antimesenterial site of bowel Clinical presentation : inflammation, bleeding, torsion, ileocaecal invagination Dg: not easy Therapy : resection of diverticulum
Mesenterial cysts Pathology :on the mesenterial site of bowel, Symptoms : chronic pain, palpable mass, can be signs of compression Dg : X-ray, ultrasound, CT, MRI Therapy : resection of bowel and mesentery
Crohn´s disease- IBD Granulomatous inflammation, which extends diffusely through the entire thickness of the bowel wall Can affect whole GI, but most commonly in small and large bowel ( skip lesions) Etiology: not known Pathology: a/acute inflammation b/chronic inflammation c/ complications
Clinical features Acute- pain, diarrhea, fever Chronic- malabsorbtion, extraintestinal Complications: obstruction, fistulas, bleeding, perforation, perianal MC Dg :History, examination, barium enema, endoscopy (cobblestone surface), ultrasound, CT, biopsy Ulcerative colitis
Crohn´s disease Thickened wall by inflammatory oedema Crohn´s disease Fissured ulcers
Treatment Dietary : without fiber, avoiding malabsorbtion, elementary diet. 2. Parenteral nutrition: 3. Drugs - 5-ASA ( sulphasalazine) - steroids- parenteral, p.o, topical - azathioprin ( IMURAN ) - Metronidazol 0,5- 1,5 - monoclonal antibodies anti TNF alfa (Remicade)