Gastro L-M Flashcards
What is Lactose intolerance?
Inability to metabolise lactose due to lactase deficiency.
What is the background of Lactose intolerance?
Congenital is extremely rare, primary in 5% of children.
Congenital: AR condition
Primary: natural non persistence of enzymes after birth, mainly in Asian population.
Secondary: damage to brush border following gastroenteritis.
NOT the same thing as CMPA. Disaccharide enxymes normally at brush border, break down lactose into glucose and galactose. 50% activity required for effective metabolism.
What history and exam findings would you see in Lactose intolerance?
Gi Hx: loose stools, frothy and explosive, bloating, cramping, flatus. II: ask about gastroenteritis recently.
Congenital: infantile diahrrea and failure to thrive.
Primary: GI symptoms increase with age due to progressive loss. Wide variety in amount of lactose expressed.
What investigations would you use for Lactose intolerance?
Hydrogen breath test: detects H2 in breath 3-6 hours after ingestion of lactose.
Stools for reducing substances: acidic as have undigested sugars.
Jejunal biopsy: rarely needed, differentiate from coeliac.
What is the management of Lactose intolerance?
Lactose is only in mammalian milk. Congenital require lifelong absolute abstinence from milk. Beware of Ca supplementation in replacement products.
Primary: low lactose diet can be tolerated.
SecondaryL complete avoidance for 4-6w to allow mucosal regeneration
What are the complications and prognosis of Lactose intolerance?
Malabsorption, failure to thrive, Ca deficiency if on different milk for Tx.
Congenital is a lifelong condition. Primary is variable depending on level of residual lactase. Secondary is transient.
What is Liver disease, Chronic?
Chronic disease of hepatic cells, leading to decrease in overall liver function.
What is the background of Liver disease, Chronic?
FHx, Hx of infection. HBV: 5% infected in world. The younger the infection the higher the rates to chronic conversion. HCV infection in 1% worldwide, cirrhosis interval 10-15y. AI hepatitis 0.1/100k. Wilsons 1/30k.
Aetiology:
Chronic active hepatitis:
· AI disease of parenchyma (AIH) or biliary tree (PSC) (-> inflammatory infiltrate with hepatocellular necrosis)
· Viral: HBV, HCV. (-> death of hepatocytes at interface between parenchyma and CT, with lymphocyte infiltration)
· DrugsL NSAID, Abx, AEDs, paracetamol.
Wilsons disease: hepatolenticular degeneration due to Cu deposits in brain, liver, kidney and cornea. (-> AR gene 13 mutation with low serum ceruloplasmin/ defective bile excretion of Cu).
Cystic fibrosis.
What history and exam findings would you see in Liver disease, Chronic?
Acute or insidious presentation
General fever, malaise, failure to thrive, loss of fat and muscle bulk.
GI: distended abdomen, scrotal swelling, dilated abdominal vein (portal HTN)
AI hepatitis: skin rash, lupus, arthritis, AIHA. Nephritis.
Wilson: KF ring >7y, neuro features >12y parkinonian.
What investigations would you use for Liver disease, Chronic?
HBV/HCV serology and surface antigen screen
AI hepatitis anti SMA Ab, IgG levels (IgG >20mg/l), ANA in PSC, liver/kidney microsomal antibodies.
Wilson disease: gene 13 mutaiton, low serum ceruloplasmin/copper. High urinary copper and hepatic copper.
What is the management of Liver disease, Chronic?
HBV: immunize at risk, support, aIFN.
HCV: aIFN.
AI hepatitis 90% respond to prednisolone/AZA
Wilson: Penicillamine (reduces hepatic/CNS copper), Zn (reduces Cu absorption), pyroxidone (prevents peripheral neuropathy) ? think of transplant
What are the complications and prognosis of Liver disease, Chronic?
End stage liver disease, coagulation and electrolyte disturbances.
Depends on underlying pathology. Px improved with adequate tx of underlying condition. AI has best prognosis.
What is Hepatitis, Acute?
Acute failure of hepatic cells to maintain normal function.
What is the background of Hepatitis, Acute?
Aetiology
Damage to hepatocytes caused by:
· InfectionL acute HepA/HepB, EBV
· DrugsL paracetamol, isoniazid, halothane, Amanita phalloides.
· Reye syndrome aspirin in patients<14y, associated with acute non inflammatory encephalopathy associated with liver damage (especially if with varicella). Shows microvescicular infiltration of the liver on pathology.
Epidemiology
Uncommon in children, EBV in adolescents.
What history and exam findings would you see in Hepatitis, Acute?
General: jaundice, encephalopathy, coagulopathy, hypoglycaemia, other electrolyte disturbances.
Encephalopathy: drowsy, alternating irritability and drowsiness. Older may have hx of aggression and being difficult.
What investigations would you use for Hepatitis, Acute?
Blood: high BR, deranged clotting, high LFT, high NH4, glucose check
ABG: may have metabolic acidosis or alkalosis
Viral serology: hep EBV
CT.MRI brain to exclude encephalopathy
What is the management of Hepatitis, Acute?
Tx complications, including:
· Hypoglycaemia: dextrose infusion
· Sepsis: IV BSAbx
· Coagulaton defects: FFP and H2 blockers/PPI to prevent gastric bleed. Vit K to be avoided unless necessary.
· Verebral odema: Hyperosmolar therapy
· Liver transplant with worsening clinical and biochemical profile.
What are the complications and prognosis of Hepatitis, Acute?
Cerebral odema, haemorrage from gastritis, sepsis, pancreatitis
High mortality though uncommon. Poor signs include shrinking in size, rising BR with falling transaminases, coagulation defects, progression to encephalopathy and coma. Patients in coma have 70% morality if no transplant.
What is Malrotation of the intestine?
Failure of normal embryological rotation of the SI around the SMA during development, predisposing to obstruction, volvulus and ischaemia.
What is the background of Malrotation of the intestine?
1/500, Common PM finding.
Normal rotation around SMA in three stages – Stage I herniation, Stage II return to abdomen with 270 counterclockwise rotation, stage III fixation.
Non rotation: midgut only rotates 180
Incomplete rotation: duodenal loop lacks 90 and caecocolic loop 180 of normal 270 rotation.
What history and exam findings would you see in Malrotation of the intestine?
Acute modgut volvulusL presents <1y, SO bilious vomiting, abdominal distension, severe pain.
Chroning midgut volvulus: recurrent abdo pain, malabsorption, Between episodes, normal.
Acute DD obstruction presents with forceful vomiting, abdominal distension, gastric waves, Compression or kinking of duodenum by Ladd bands.
Chronic DD obstruction Presents in infancy with bilious vomiting, intermittent abdominal pain.
Acute obstruction tachycardia, distension, tinkling bowel sounds.
Infarction/necrosisL shock (high HR, pallor, high CRT, low responsiveness( pyrexia and acute peritonitis signs.
What investigations would you use for Malrotation of the intestine?
Bloods: high WCC, low Hb if bleeding, UW, Acidosis with high lactate can be present if vessel obstruction present.
AXR: Variable appearance with dilated loops of bowel or gasless abdominal field.
UGI contrast: if patient stable, preformed on all infants with bilious vomiting. Corkscrew appearance with volvulus or DJ flexure to the right of midline with malrotations (normal is on the left)
What is the management of Malrotation of the intestine?
Preoperative: correct fluid and electrolyte imbalance, BSAbx, NG tube insertion, ?UGI if stable.
Ladd procedure: reduction of volvulus, division of mesenteric bands, placement of small bowel on right and large bowel on left, and appendicectomy. Transverse supraumbilical incision.
What are the complications and prognosis of Malrotation of the intestine?
Strangulaiton and necrosis, perforation, peritonitis, septic shock. Loss of small bowel leading to SBS.
Good with prompt surgical management. Pgx dependson bowel preservation extent.
