Intestine

Question 1

Small intestine: Circular folds of the mucosa and submucosa which increase the surface area of the and decrease the velocity of he movement of the luminal contents

Answer 1

Plicae circulares

Question 2

Small intestine: Finger-like protrusions of the lamina propria covered by tightly packed absorptive cells

Answer 2

villi

Question 3

Small intestine: Structural modifications to the apical cell membrane of epithelial cells, increasing the available surface area for absorption

Answer 3

Microvilli

Question 4

Small intestine: Invaginations of the epithelium into the lamina propria

Answer 4

Crypts of Lieberkuhn

Question 5

Small intestine: Secrete mucus to protect lumen from stomach acid and traumatic damage

Answer 5

Goblet cells

Question 6

Small intestine: Hormone releasing cells within gut epithelium

Answer 6

Endocrine cells

Question 7

Small intestine: Pyramid shaped cells found at the base of small intestinal crypts. Produces products that are important in protecting the intestinal epithelium against microbes

Answer 7

Paneth cells

Question 8

Small intestine: Branched tubuloalveolar glands with mucous-secreting acina located primarily in the duodenal submucosa. Secretes a bicarbonate rich fluid which neutralises acidic chyme

Answer 8

Brunner’s glands

Question 9

Small intestine: Aggregation of plasma cells, lymphocytes, mast cells, leucocytes and fibroblasts found throughout the small intestine

Answer 9

Lymphoid tissue(known as Peyer’s patches in terminal ilium)

Question 10

Large intestine: The mucosa is devoid of villi, instead it is rich in ………… which are similar to those in the small intestine except for the absence of Paneth cells and a larger amount of ……………

Answer 10

Crypts and Goblet cells

Question 11

Congenital disorder which presents soon after birth. Diagnosed on the basis of persistent vomiting of bile-containing fluid and failure to pass meconium. Most commonly found in the duodenum or small intestine and rarely in the colon

Answer 11

Atresia(complete occlusion) and stenosis(incomplete obstruction)

Question 12

An obstruction caused by twisting of the stomach or intestine

Answer 12

Volvulus

Question 13

Outpouching of the ileum on approximately 60 to 100cm from the ileocaecal valve. Caused by the incomplete regression of the vitelline duct.

Answer 13

Meckel’s diverticulum

Question 14

An instance of the inversion of one portion of the intestine within another

Answer 14

Intussusception

Question 15

Intestinal aganglionosis results from a failure of neuroblasts to migrate from the vagus into the developing gut. Under normal circumstances parasympathetic tone is modulated within the ganglia by sympathetic innervation. With the absence of myenteric ganglia the parasympathetic supply is left unchecked leading to spasm of the circular muscle and intestinal obstruction

Answer 15

Hirschsprung’s disease

Question 16

Chronic inflammation resulting from sensitivity to gluten components in cereals. Damage to he surface enterocites of the small intestine severely reduces their absorptive capacity. Causes vilous atrophy, crypt hyperplasia and intraepithelial lymphocytosis in duodenal or jejunal biopsy. Results in malabsorption, weight loss and iron-deficiency anaemia

Answer 16

Coeliac disease

Question 17

Progressive malabsorption syndrome seen in patients who live/have lived in the tropics. Thought to be secondary to bacterial contamination of the small bowel. Histologically resembles coeliac disease. Unlike coeliac disease, symptoms do no improve upon removal of gluten. Prognosis is very good as long as the correct diagnosis is made, usually treated with tetracycline and folate for 6 months

Answer 17

Tropical sprue

Question 18

Gram-positive bacillus which is non-invasive but produces a toxin which is responsible for enteritis. Some patients taking a broad spectrum antibiotic develop diarrhoea resulting from the overgrowth of this commensal bacterium

Answer 18

Colostridium difficile enteritis

Question 19

Many drugs affect the GI tract but due to their widespread use ………. are the most important. Longer term use can lead to small bowel ulceratiuon and strictures. Occasionally ulceration can occur in caecum and proximal colon

Answer 19

Non-steroidal anti-inflammatory drugs (NSAIDs)