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
Where is S.aureus found
Cold and cured meats- caused by staphylococcal enterotoxins A and B
Vibrio cholera
Profuse rice water diarrhoea
Severe dehydration resulting in weight loss
Not common amongst travellers
Differences between Secretory and Osmotic diarrhoea
Secretory- ion transport defect, not relieved by fasting, small osmotic gap. Caused by bile toxins, enterotoxins, laxatives, neuroendocrine, tumours, medications, allergies
Osmotic- Malabsorption, will stop after fasting, large osmotic gap. Caused by laxatives (osmotic), non-absorbed food, congenital/acquired defects
Osmotic laxative
Lactulose
Domperidone
Increases motility without purgation
Muscles of the anterolateral wall
(1) Flat muscles – three flat muscles (external oblique, internal oblique and transversalis abdominis muscles), situated laterally on either side of the abdomen.
(2) Vertical muscles – two vertical muscles (rectus abdominis and pyramidalis), situated near the mid-line of the body.
Difference between direct and indirect hernias
Direct inguinal hernias occur medial to the inferior epigastric vessels when abdominal contents herniate through a weak spot in the fascia of the posterior wall of the inguinal canal, which is formed by the transversalis fascia.
Indirect inguinal hernias occur when abdominal contents protrude through the deep inguinal ring, lateral to the inferior epigastric vessels; this may be caused by failure of embryonic closure of the processus vaginalis.
The percentage of GI cases in the under 5 caused by a viral cause
60%
The main agent that causes Gastroenteritis
Norovirus- a single stranded RNA virus
Infliximab
A monoclonal antibody directed against tumour necrosis factor alpha. Treats psoriasis, UC and Crohns
Aminosalicyate
Consists of the sulphonamide sulfapyridine linked to 5-aminosalicylic acid, the latter forms the active moiety when released in the colon
Paraumbilical hernias
More common in adults (especially women) than children. Associated with obesity and weak abdominal muscles
Divarication of the abdominal wall
Not considered a hernia. Occurs when the rectus abdominus muscle becomes separated from the midline. The linea alba / aponeurosis becomes stretched but there is no hole. Not surgically treated
Blood supply to the transverse colon
The transverse colon receives its blood supply from both superior and inferior mesenteric arteries. The proximal two thirds (lying towards the right colic flexure) are supplied by the middle colic artery, which is a branch of the superior mesenteric artery. The distal third (lying towards the left colic flexure) is supplied by the left colic artery, which is a branch of the inferior mesenteric artery.
Types of Granulocytes
Eosinophil, Neutrophil, Basophil, Mast cell
3 causes of increased vascular permeability
1) Direct cell damage
2) Endothelial cell retraction
3) Leukocyte mediated endothelial injury
Sentinel cells
Mast cells, Macrophages and Dendritic cells
What’s the side effects for adrenoreceptor antagonists
1) Tremor
2) Tachycardia
3) Cardiac dysrhythmias
Nerve supply to the sublingual and submandibular duct
Parasympathetically by the Chorda tympani branch of the facial nerve (CNVII)
Nerve supply to the parotid gland
Parasympathetically supplied by the Glossopharyngeal nerve
What can cause a pleural effusion
Hypervolemia, decreased fluid protein, haemothorax, infection and inflammation
Types of inflammation
1) Serous inflammation- skin blisters due to burns
2) Catarrhal inflammation- Allergic rhinitis
3) Fibrinous inflammation- fibrinous pericarditis
4) Haemorrhagic inflammation- acute pancreatitis
5) Suppurative/Purulent- abscess due to pyrogenic bacteria
