Questions Flashcards
Digesting Maltotriose and Maltose
Enzyme- Maltase
Products- Glucose
Digesting Lactose
Enzyme- Lactose
Products- Glucose and Galactose
Digesting Sucrose, Maltotriose and Maltose
Enzyme- Sucrase
Products- Fructose and Glucose
Digesting α-limit dextrins, (Sucrose), Maltose & Maltotriose
Enzyme= Sucrase-isomaltase Products= Glucose and Fructose
Products of colonic fermentation
Digestion of carbohydrates by bacterial enzymes (to varying degrees) produces short-chain fatty acids, H2 & CH4.
Lactase deficiency
Lactose intolerance (diarrhoea, cramps, flatulence). Increased breath H2 due to bacterial digestion.
Glucose-galactose malabsorption
Defective intestinal SGLT1.
Osmotic diarrhoea.
Increased breath H2 due to bacterial digestion.
Sucrose-Isomaltose deficiency
Branched starch (alpha-limit dextrins) not digested fully to glucose.
Osmotic diarrhoea.
Increased breath H2 due to bacterial digestion.
Trypsin deficiency
Trypsin deficiency - marked protein malabsorption.
Severe diarrhoea, failure to thrive, hypoproteinaemia & resulting oedema.
Enterokinase deficiency
Presents as trypsin deficiency
Hartnups disease
Autosomal-recessive
Defective neutral amino acid transport; System B (apical membrane).
Neutral aminoaciduria- neutral amino acid are absorbed by alternative amino acid transporters or in the di/peptide form but less are reabsorbed by the kidney, thus lost in the urine
Increase protein in diet to overcome any potential deficiencies, e.g. tryptophan
Cystinuria
Autosomal-recessive.
Defective system B0,+ or b0,+ (apical membrane).
Increased urinary excretion of cystine (stones for if urine is neutral or acidic, precipitates out) & cationic amino acids.
No nutritional imbalance as absorption in di/tripeptide form compensates for defective amino acid uptake. However cationic amino acids and cystine liberated in the body are not reabsorbed by the kidney
Lystinuric protein intolerance
1) Autosomal-recessive.
2) Defective cationic amino transport, System y+L, (basolateral membrane).
3) Cationic aminoaciduria. Vomitting, diarrhoea and coma when fed protein.
4) Arginine & ornithine deficiency- restricted urea cycle (hyperammonaemia).
5) Lysine deficiency - skeletal & immunological abnormalities.
6) Restrict protein in diet. Supplement with citrulline (neutral) to increase urea cycle function as it can enable sufficient urea cycle function for adequate protein absorption to live.
Nucleic acid absorption
1) Digestion in the Gut lumen- Pancreatic DNAse and RNAse
2) Absorption in small intestines- Nucleotides and Nucleosides. Na+ coupled and accumulative transport (N1, N2). Facilitative transport
3) Semi-essential- supplemented in formula milk
Differences between the jejenum and Ileum
Jejenum- left upper quadrant, thick wall, longer vasa recta, few arcades, less fat in mesentery
Ileum- lower right quadrant, thin wall, shorter vasa recta, many arcades, more fat in mesentery, Peyers patch
Where does the rectum begin
S3- rectosigmoid junction
Blood supply to the rectum
Superior rectal artery- branch of IMA
Middle rectal artery- branch of internal iliac
Inferior rectal artery- branch of internal pudenal artery from the internal iliac
Femoral hernias
Herniation of the abdominal contents through the femoral canal. Occurs below the inguinal ligament at the top of the thigh. Goes through the femoral ring.
Risk of- incarceration, obstruction, strangulation
Contents of the femoral triangle
Femoral nerve, femoral artery, femoral vein. Y-fronts and femoral canal (containing lymphatic vessels and nerves
Identifying direct hernias
Reduce hernia, palpate the deep inguinal ring and ask the patient to cough, if it reappears then its a direct hernia
Direct inguinal hernia
1) The peritoneum enters the inguinal canal via a weakness in Hesselbachs triangle and will proceed to the superficial inguinal ring.
2) Occurs medially to the epigastric vessels
Hesslebachs triangle
Rectus abdominis muscle- medial border
Inferior epigastric vessels- lateral border
Poupart’s ligament (inguinal ligament)
Indirect inguinal hernia
1) More common than direct
2) Peritoneum enters the inguinal canal via the deep inguinal ring and proceeds down the inguinal canal to the superficial ring and reaches the scrotum
3) Lateral to the epigastric vessels
4) Can lead to a big herniations of the peritoneal contents such as the bowel down into the scrotum
Identifying an indirect inguinal hernia
Reduce the hernia, palpate the deep inguinal ring and ask the patient to cough. The hernia will remain reduced
