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FRACP Exam > Gastroenterology > Flashcards

Gastroenterology Flashcards

1
Q

Absorption small bowel

A
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2
Q

Achalasia

A

incidence: 1.6/100,000

pathophysiology:

  • lack of peristalsis of lower 1/3 oesophagus/relaxation LES
  • LES only opens when pressure of accumulated food in oesophagus>LES tone

causes:

  • autoimmune, malignancy, Chagas disease (parasites)

clinical:

  • dysphagia, reflux, weight loss, nocturnal cough

diagnosis: barium swallow, manometry

management: medications (nitrates/CCB), botox, dilatation, myotomy

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3
Q

Acid/Base diarrhoea

A

volume: up to 6L loss per day

fluid: electrolyte poor except for HCO3

pathophysiology:

  • renin released secondary to hypovolaemia
  • increased renal Na absorption and H/K secretion (H>K)
  • loss of Na poor fluid with increased Na reabsorption

investigations

  • metabolic acidaemia
  • hypernatraemia/hyperosmolality
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4
Q

Acid/Base vomiting

A

electrolytes: high HCl/K

pathophysiology:

  • renin, increased NA reabsorption limited by hypokalaemia/alkalaemia

investigations:

  • metabolic alkalosis, hypernatraemia, hypokalaemia
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5
Q

Albumin

A

synthesis: in liver at twice basal rate

half-life: 3 weeks

2/3 stored: extravascular/extracellular

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6
Q

Alkaline Phosphatase (ALP)

A

production: liver, bile duct, kidney, bone

increase: biliary obstruction, liver disease, bone disease, hyperPTH, adolescence

decrease: hypophosphatasia, anaemia, fulminant Wilson’s disease

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7
Q

Allergic proctocolitis

A

timing: day 1 to 3 months

symptoms: streaks blood/mucous in stool with occassional diarrhoea

investigations: increased WCC/eosinophils in stool, nodular lymphoid hyperplasia (25%)

cause: hypersensitivity to cow’s milk, less commonly soy sensitivity

treatment: protein hydrolysate formulas (neocate)

prognosis: usually resolves within 1 year

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8
Q

Alpha 1 Antitrypsin deficiency

A

Defective production alpha 1 antitrypsin

>100 alleles AAT

Deficient: Z allele most common type

SERPINA 1 gene

AAT is an antiprotease: protects against proteases from neutrophils

Excessive abnormal protein destroys cells in lung/liver/skin

Lung: elastase not inhibited, destruction elastin, emphysema

  • lung symptoms >20years

Liver: AAT form accumulates in hepatocyte ER causing injury

  • presents in childhood: neonatal cholestasus, hepatomegally with increased aminotransferases, liver disease, bleeding

Cirrhosis and liver failure in 15%

Leading cause of liver transplantation in neonates

Investigations: serum level<35% normal

Management:

  • IV infusion, transplant
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9
Q

Alanine Transaminase

A

location: high concentration in liver, small in muscle

  • more specific to muscle than AST but longer half life
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10
Q

Antacids

A

drugs/side effects:

- aluminium hydroxide: constipations, low Ph and seizures

  • magnesium hydroxide: diarrhoea, hypotonia, coma
  • calcium carbonate: chelate other drugs
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11
Q

Antidiarrheals

A

Bile acid sequestrants

- drugs: cholestyramine

  • use: diarrhoea caused bile excess bile secretion

Bismuth subsalicylate

  • drug: peptobismul

Opiod receptor agonists

  • drug: loperamide
  • mechanism: enteric nerves, epithelial cells, muscles causing decreased GI secretion/absorption

(low CNS penetration)

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12
Q

Antiemetics

A

drugs:

  • serotonin antagonists: ondansetron
  • dopamine antagonists: prochlorperazine

mechanism: centrally acting

side effects: constipation

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13
Q

Aspartate Aminotransferase (AST)

A

High conc in liver, heart, SM, kidney, pancreas, lung, WBC, RBC

Shorter half life

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14
Q

Autoimmune hepatitis

A

Type 1: classic

  • ANA and/or ASMA; ASMA thought to be reflective of more specific anti-actin Ab
  • women in all age groups

Type 2:

  • Ab to liver/kidney microsomes (ALKM-1) and/or to liver cytosol antigen (ALC-1)
  • disease of girls and young women

Symptoms

  • asymptomatic to fulminant hepatic failure
  • many present with cirrhosis: nausea, abdo pain, itching
  • associated arthritis
  • associated autoimmune disease

Diagnosis: elevated transaminases>bilirubin/ALP, elevated globulins + IgG (80%)

Histology: chronic necroinflammatory disorder

Management: corticosteroids, azathioprine, 6-MP, transplant

Prognosis: SMA/ANA more severe disease

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15
Q

Biotin

A

Deficiency: dermatitis, seborrhoea, anorexia

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16
Q

Biliary atresia

A

1: 10,000
cause: progressive postnatal obliteration of entire extrahepatic biliary tree at or above porta hepatis
symptoms: jaundice, pale stool

Ultrasound: lack of gallbladder, heterogenous large liver

Management: Kasai procedure (hepatoportoenterostomy) less than 8 weeks

  • if flow not establishes 1st months: progessive obliteration/cirrhosis

Complications: portal hypertension

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17
Q

Campylobacteriosis

A

definition: gram negative rod bacteria flagella

source: contaminated food

timing:

  • onset diarrhoea 2 to 5 days after infection
  • symptoms lasting 8 days

clinical:

  • inflammatory bloody diarrhoea, cramps, fever, pain

pathogenesis:

  • infect jejunum, ileum, colon
  • produce toxin inhibits immune system
  • adherence and invasion
  • taken up by cytoplasmia vacuole
  • assoc guillaine barre syndrome

treatment:

  • macrolide (azithromycin)
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18
Q

Campylobacter jejuni

A

Fimbriae attached and invade intestinal epithelium

Bacterial surface proteins (PEB1, CadF) help to colonize and invade cells

Causes acute mucosal inflammation with edema, cellular infiltration lamina propria, crypt abscess formation

Similiar to salmonella/shigella

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19
Q

Carbohydrate absorption

A
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20
Q

Carbohydrate digestion

A

All carbs require hydrolysis to monosaccharides before absorption

Glucose and galactose are transported by Na-dependent active transport

Fructose is transported by Na-independent facilitated diffusion

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21
Q

Caroli disease

A

1:1000,000

autosomal dominant assoc ARPKD

segmental dilation intrahepatic bile ducts

symptoms: fever, abdominal pain, hepatomegally

Pathophysiology: stagnation of bile, biliary sludge, intraductal lithiasis

Imaging: demonstrates bile duct ectasia

increased risk cholangiocarcinoma

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22
Q

Causes of pancreatic insufficiency

A
  1. CF
  2. Schwachman-Diamond
  3. Starvation
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23
Q

Celiac disease autoantibodies

A

Sensitivity/Specificity

Tissue transglutaminase 90-100/95-100

Anti-endomysial Ab 93-100/98-100

Antigliadin Ab Ig A 52-100/72-100

Antigliadin Ab Ig G 83-100/47-94

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24
Q

Cholestasis

A

Conjugated hyperbilirubinaemia always pathological

  • prolonged elevated conj bili>14days and pale stools, dark urine
  • term: neonatal hep/biliary atresia (70-80%)
  • preterm: TPN/sepsis

Intrahepatic:

  • hepatocyte injury: metabolic, viral
  • bile duct injury: intrahepatic bile duct paucity

Extrahepatic:

  • biliary atresia
  • choledochal cyst
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25
Q

Chronic liver failure

A

symptoms: scleral icterus, palmar erythema, clubbing, wasting, portal HTN, cholestasis, hypotonia

management:

  • liver transplant: 86% long term survival
  • medications: immunosuppression, antibacterial, antifungal, antiviral, antiHTN, supplements, bile drainage
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26
Q

Chronic pancreatitis

A

30-40% risk DM

May not have raised enzymes

Causes: obstructive, genetic (cationic trypsinogen gene defect SPINK1)

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27
Q

Clostridium Difficile

A

Gram positive rod

Toxin A (enterotoxin): act on intestinal mucosa

Toxin B (cytotoxin): increases vasc permeability

  • both cause cell death

Increased infection 2nd/3rd generation cephalosporin

Diagnosis C-difficile or toxin in stool

Culture doesn’t differentiate toxin producing from non toxin producing

Sigmoidoscopy: nodules/plaques

Treatment vancomycin or metronidazole

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28
Q

Coeliac disease

A

1:100 F:M, 2:1. Caucasians mainly.

Usually presents 10-40yr

High risk groups: 10% 1st degree relative risk, T21 (16% affected), T1DM (2-5%), IgA deficiency (10%), Turner’s, William’s, Autoimmune thyroiditis (2-5%)

Genetics:: MHC short arm ch6 – gene cluster of HLA class II. HLA-DQ2 and/or DQ8 found in 99% of ppl w coeliac (40% in the general population)

Pathophysiology: gluten to gliadin, enters cell via injury, deaminated gliadin picked up HLA FQ2 + DQ8, T cell activation, B cell activation, inflammatory cascade, produce antigliadin/endomysium/tTG

Biopsy: villous atrophy

Tx: gluten free diet, resolution of symptoms weeks to months

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29
Q

Colonic duplication

A

tubular or spherical structures firmly attached to intestine with common blood supply

associations: anomalies of urinary/genital anomaly
presentation: volvulus, intussusception at lead point
symptoms: abdominal pain, mass, GI bleeding

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30
Q

Congenital chloride diarrhoea

A

genetic: AR mutation SLC26A3

cause: defective chloride/bicarb transport mechanism distal ileum/colon

clinical: severe watery diarrhoea at birth

investigations: hypokalaemia, hypochloremia, alkalosis, stool Cl>Na

management: IVF

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31
Q

Cow’s milk protein allergy

A

Immune mediated igE or non IgE response

Most common allergy in young child (2% <4yrs)

3rd most common cause of anaphylaxis

Onset days- weeks after introduction cow’s milk

IgE mediated: mild anaphylaxis minutes to 2 hrs

Mixed IgE/nonIgE: atopic eczema, allergic eosinophilic gastroenteritis

NonIgE: delayed >2hrs

GI allergy is NonIgE

Most develop tolerance

Diagnosis: Food challenge or Cow’s mild specific IgE RAST

Treatment: soy formula (10-20% soy allergy also), extensively hydrolysed, AA formula

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32
Q

Crigler-Najjar

A

Type 1: AR severe

  • absent UGT
  • jaundice d2-3
  • phototherapy for life

Type 2: AD milder

  • UGT levels low but detectable
  • responds to phenobarbitone
  • late onset childhood/adulthood
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33
Q

Crohn’s disease

A

7/100,000 peak 8-14yrs M:F 1:1

Relapsing remitting

Site: any part GIT

  • favors terminal ileum
  • 35% involves ileum alone
  • 45% involves ileum and colon
  • 20% involves colon alone (preference for right side)
    • Colonic involvement right-sided*
    • Rectosigmoid often spared*
    • Upper GIT more commonly involved in kids >adults*
  • skip lesions

Histology:

  • transmural, non caseating granulomas, goblet cells present, islands normal tissue

Smoking:

  • twice as common in smokers

Symptoms: malaise, fever, anorexia, nausea, vomiting, weight loss, bleeding rate exept with colitis

Examination: RIF mass, fever, clubbing, abdo tenderness, anorectal disease, perianal disease (25%), oro-facial granulmoatosis, apthous ulcers

Diagnosis:

  • pANCA (20%) – if +ve, more likely to have UC like distribution
  • ASCA (40-80%): ASCA assoc with more severe disease, fistulising disease
  • Anti-OmpC : potential marker of IBD (50%)
  • CBir1 – other antimicrobial antibody

Treatment: steroids, 5-ASA, thiopurines (azathiopurines, 6-MP), infliximab

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34
Q

Cryptosporidiosis

A

definition: parasitic protozoan cryptosporidium

source: transmitted as microbial cysts via faecal-oral route

timing: may be acute or chronic

  • symptoms 5-10 days after infection and last up to 2 weeks

clinical:

  • significant watery diarrhoea, fever, abdominal pain, jaundice, reactive arthritis
  • can spread to biliary tract causing cholestasis

pathogenesis: (adherence/inflammation)

  • parasite attaches duodenal brush border damaging it
  • malabsorption and osmotic diarrhoea
  • enveloped membrane and become intracellular
  • excreted as oocytes

detection: microscopy, staining, Ab detection

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35
Q

Cryptosporidium

A
  • Implicated as cause of persistent diarrhoea in developing world
  • Transmission through infected animals; person-person; contaminated water
  • Incubation 2-14 days
  • Assocated with profuse, watery, nonbloody diarrhoea +/- vomiting, abdo pain, nausea, anorexia, myalgia, weakness, headache, fever
  • Malabsorption, weight loss, malnutrition in severe cases
  • Usually self limiting in immunocompetent patients, although diarrhoea may persist for several weeks (oocyst shedding may persist many weeks after symptoms resolve)
  • Rx: nitazoxanide
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36
Q

Cyclic vomiting

A
  • = at least 5 attacks, or a minimum of 3 attacks in 6 months
  • Severe episodes, well between, each episode similar
  • Early morning
  • Positive FHx of cyclical vomiting OR migraine
  • Chronic sinusitis – only infective correlation
  • Metabolic
  • Consider malrotation
    • Rx: anti-migraine
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37
Q

Cystic Fibrosis (gastric issues)

A

clinical: early abdo/bowel distension, vomiting, rectal mucus plugging

complications: meconium ileus (15%), 50% associated volvulus, jejunoileal atresia, bowel perforation, meconium peritonitis

AXR: distended/thickened loops of intestine

  • meconium with swallowed air: ground glass sign
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38
Q

Dermatitis herpetiformis

A

Most common skin condition associated coeliac disease

Extensor surfaces and trunk

Itchy

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39
Q

Diagnosis Coeliac disease

A

Biopsy to confirm anyone with positive serology or high risk CD

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40
Q

Dubin Johnson Syndrome

A

incidence: AR, rare except in sephardic jews

genetics: ABCC2 gene

pathophysiology: increased conjugate bilirubin due to impaired excretion of bilirubin glucuronidase

clinical: mild conjugated hyperbilirubinaemia

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41
Q

Duodenal atresia

A

epidemiology: 1/10,000, 50% prems, 50% chromosomal abnormalities (33% T21)
cause: failired re-canalisation of duodenal lumen due to persistence of replicating epithelial cells
pathophysiology: thin membrane occluding lumen, fibrous cord between, gap between 2 segments, web
associated: CHD (30%), malrotations (20%), annular pancreas (30%), renal (15%), TOF (10%)
clinical: bilious vomiting w/o distension 1st day life, hx polyhydramnios

AXR: double bubble

treatment: drip and tuck, surgical correction
prognosis: 90% survival

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42
Q

Enterohaemorrhagic ecoli

A

definition: gram negative rod

source: food (raw beef), milk

timing: onset 1-8 days lasting 5-10 days

clinical: severe bloody diarrhoea, pain, vomiting

  • sometime renal failure causing HUS (10%) (<5yrs) in which RBCs destroyed causing anaemia/thrombocytopaenia and kidney failure

pathogenesis:

  • strains of ecoli with shigella like toxin
  • A/B subunits allow attachment/uptake/apoptosis

diagnosis: Ecoli O157:H7 requires special media to grow

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43
Q

Energy content foods

A

protein: 4kcal/g (15% intake)

carbohydrate: 4kcal/g (50% intake)

fat: 10kcal/g (30-50% intake)

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44
Q

Enterotoxigenic E.coli

A

Colonises and adheres to enterocytes small bowel via surface pili

Hypersecretion of fluids/electrolytes

2 toxins: heat labile enterotoxin (LT) or heat stable enterotoxin (similiar structure to cholera toxin)

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45
Q

Enterotoxigenic ecoli

A
  • leading cause of bacterial diarrhoea developed countries

source: water/food contaminated faeces

timing: incubation 1-3 days, duration 3-7 days

clinical: watery diarrhoea, cramps, vomiting, fever

pathogenesis:

  • enterotoxins LT/ST presence produces more severe diarrhoea
  • B subunit attaches/A enters causing secretion Cl/H2O

diagnosis: stool culture

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46
Q

Eosinophilic oesophagitis

A

Mixed IgE/nonIgE food protein allergy

Boys>girls, caucasian

Causes: genetic, environment, Tcell

Clinical, dysphagia, abdo pain, vomiting, food impaction, GORD, diarrhoea

Associated atopy

Diagnosis: biopsy (mucosal inflammation, eosinophilic infiltrates/microabscesses/furrowing)

Treatment: elimination diet (milk most common trigger), steroids, topical

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47
Q

Extensively hydrolysed (neocate, MCT peptide)

A

eg neocate, MCT peptide

  • Amino acids, coconut/vegetable oils (combo of MCT>LCT), carb = glucose
  • Very high osmolarity
  • Indications: SBS, pancreatitis, severe multiple food protein allergy
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48
Q

Extrahepatic Biliary Atresia

A

1:10,000

inflammation of the bile ducts leading to progressive obliteration of extrahepatic biliary tract

Symptoms: jaundice, hepatosplenomegally, acholic stool

US: absence of gall bladder

Assessment: hepatobiliary scintigraphy

Treatment: Kansai procedure

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49
Q

Familial Adenomatous Polyposis

FAP

A

genetics: AD variant tumour suppressor gene APC (adenomatous polyposis coli)

incidence: 1/10,000

clinical: multiple colorectal adenomatous polyps (>100)

  • GI bleeding, abdominal pain, diarrhoea

diagnosis: suspected if >10 colorectal adenomas and then genetic testing

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50
Q

Fat digestion

A

dietary fat: triglycerides (3 fatty acid molecules + glycerol backbone)

digestion:

  • lipase in stomach emulsifies lipid droplets
  • pancreatic lipase/colipase/esterase/phospholipase hydrolyse TG in duodenum to 2 FA + monoglycerides
  • products of lipolysis are insoluble (require bile salts)
  • bile salts (micelles) solubilise FA by incorporating them into their structure

absorption:

  • in cell monoglycerides + FA re-esterified to TG (in phospholipid/cholesterol/protein to form chylomicrons) which go into the lymphatics
  • MC TG are water soluble don’t need micelles; they are unchanged FFA in the portal venous system
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51
Q

Folate

(vitamin B9)

A

source: liver, kidney, yeast, green vegetables, nuts

amount: 50microg/day, lasts 3-4 months

absorption: duodenum/jejunum

decreased absorption: methotrexate, trimethoprim, OCP, phenytoin, phenobarbiton

cells: enters cell via specific receptor

- folic acid to dihydrofolate reductase to tetrahydrofolate FH4

causes of deficiency:

  • congenital folate malabsorption (AR, onset 3 months)
  • congenital DHF reductase deficiency (onset infancy)

clinical: anaemia, glossitis, jaundice, bleeding, infections, NO NEURO SX

diagnosis: macrocytic anaemia, normal B12, low folate/methylmalonic acid, increased homocysteine

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52
Q

Food Allergy Syndrome

A
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53
Q

Hereditary fructose intolerance

A

incidence: rare AR

definition: IEM with absence enzyme aldolase B

clinical: vomiting, hypoglycemia, jaundice, hemorrhage, hepatomegaly, hyperuricemia and potentially kidney failure after introduction of fruit into diet

diagnosis: DNA screening, fructose challenge

treatment: avoid fructose

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54
Q

Gamma-glutamyl Transpeptidase

A

Biliary tree and hepatocytes

Raised in obstruction (with ALP)

Inducible enzyme

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55
Q

Gastric acid secretion

A

INCREASE gastric acid secretion:

  • Histamine (via H2 receptors)→↑cAMP
  • Acetylcholine (via M3 muscarinic receptors)→ ↑ intracellular free Ca2+
  • Gastrin (via enterochromaffin-like cells)→ ↑ histamine release

DECREASE acid secretion:

  • PGE2 (decreased intracellular Ca+)
  • ? sympathetic drive, intestinal peptides eg. CCK, secretin
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56
Q

Gastric rugal hypertrophy

A

aka Menetrier’s disease

definition: hyperplasia of gastric pits and superficial epithelium causing large mucosal folds of stomach

(Replacement normal gastric glands and parietal cells by hyperplastic mucus secreting cells)

pathophysiology:

  • increased permeability results in hypochlorhydria/protein loss

clinical: epigastric pain, vomiting, upper GI bleeding

causes: childhood form associated CMV

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57
Q

Gastrin

A

Released by G cells in stomach, duodenum, pancreas

Stimulates secretion HCl by parietal cells of the stomach/aids in gastric motility

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58
Q

GERD

A

GERD is physiological

40% infants vomit once per day

Resolution 50% by 6m, 75% 1yr, 95% 18m

Gastric acidity increased in first 4 months

Cause: transient LES relaxations

Anatomical issues: hiatus hernia, defective crural/diaphragmatic musculature, intermittent intestinal obstruction

Functional: achalasia, increased intrabdominal pressure, theophylline

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59
Q

GI anatomy

A
  • Foregut = from pharynx to upper ½ of duodenum (including liver, gallbladder and pancreas)
  • Midgut = distal ½ of duodenum to proximal 2/3 of transverse colon
  • Hindgut = distal 1/3 of transverse colon to rectum
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60
Q

GI blood supply

A
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61
Q

Giardia Lambia

A

Definition: protozoan parasite

Incidence: most common intestinal paracyte

Tranismission:

  • faecal oral transmission via water/food disease

Pathophysiology:

  • ingest cysts (10-100), each ingested cyst then makes 2 trophozoites
  • trophozoites colonize the lumen of the duodenum, and proximal jejunum, where they attach to brush border and multiply in a binary fission
  • cause villous atrophy

Incubation: 1-2 weeks

Clinical:

  • diarrhoea, malaise, foul smelling/fatty stool, abdominal pain. bloating, vomiting, fever
  • NO blood/mucous/WCC in stool
  • symptoms last up to 2 weeks and may become chronic
  • varying degrees of malabsorption occur – sugars, fats and fat soluble vitamins
  • may become chronic in 50% of patients waxing/waning for months

Diagnosis:

  • stool microscopy (90% diagnosed 3 stool specimens)
62
Q

Gilbert’s Disease

A

2-5% (30% carriers)

autosomal recessive

decrease UDPGT activity (30-40%)

asymptomatic unconjugated SBR in illness/stress/fasting

normalises with phenobarbitone

increases with nicotinic acid

decreased clearance free FA

63
Q

Crigler-Najjar

A

autosomal recessive

cause: deficiency bilirubin UGT (uridine diphosphate glucuronosyl transferase)

Investigations: normal LFTs/liver histology

Types:

type 1- AR, high risk kernicterus, lifelong phototherapy/liver transplant

type 2-AD, may require PT, phenobarbitone activates some enzymes

64
Q

Gilbert’s syndrome

A

chromosome 2 repeat in TATA box

incidence: 7% M>F
cause: mild bilirubin UGT deficiency
symptoms: jaundice
tx: no treatment, normal lifespan

65
Q

Glucose-galactose malabsorption

CGGM

A

incidence: 1/500,000

definition: AR mutation sodium/glucose co-transporter (SGLT-1)

clinical: early osmotic diarrhea, dehydration, acidosis

diagnosis:

  • reducing substances in stools
  • glycosuria despite hypoglycaemia
  • breath H2 positive

treatment: fructose based diet

66
Q

GORD

A

transient lower oesophageal sphincter relaxation

physiology: full stomach, LES relaxation, secondary peristalsis of oeso
neonates: 40-50x per day, resolves by 12months, uncomplicated in 60%
complications: reflux apnoea, reflex bronschospasm, pain, bleeding, Barret’s
associated: poor weight gain
management: conservatively, trial cow’s milk elimination (3 days), breast feed, thicken feeds, drugs not 1st line, fundoplasty

67
Q

H2 Blockers

A

drugs: ranitidine, cimetidine

pharmacology: decrease parietal HCl secretion

use: GORD, PUD, gastritis

68
Q

Hepatitis B

A

virus: hepadnavirus

prevalence: <1%

pathogenesis: lifelong non curable immune mediated cell injury

risk factors:

  • age: younger higher risk chronic hep ?(neonate 95%, early child 25%, later child 10%)
  • perinatal exposure to HBsAg +ve mother (highest HBeAg positive (80% infected) negative (10%))
  • breast feeding DOES NOT increase risk
  • IVDU
  • sex
  • blood transfusion: HBV 1:150,000
  • needstick: HBV 33%

clinical:

  • acute HBV: 6-7wks post exposure: ALT, lethargy, anorexia, malaise, 8-9wks jaundice for 4 weeks
  • chronic HBV (10% of acute): HBsAg >6m, cirrhosis, HCC

treatment: only if abnormal LFTs

  • IFNa2b: 25% eradication rate
69
Q

Hepatitis B testing

A

Perform HBsAg, Anti-HBs, Anti-HBc

  • HBsAg first to rise in infection but falls rapidly
  • Anti-HBc IgM rises realy and remains mths-years
  • Anti-HBs marks recovery and protection
  • Vacinated Anti-HBs Ab positive
  • Previous infection Anti-HBc and Anti-HBs positive
  • HBeAg present in active or chronic infections
70
Q

Hepatitis C

A

virus: hepacivirus

risk factors: blood, sex, usually perinatal in babies (high HCV titre/HIV positive)

perinatal transmission (6% if mother HepC RNA +ve)

  • develop 90% chronic infection, 10% transient viremia
  • breastfeeding NOT contraindicated
  • HepC Ab at 12-18 months

pathologenesis: direct cytotoxicity to hepatocytes

clinical: acute illness mild

serology: HCV RNA diagnostic, anti-HCV Ab useful for chronic

  • chronic HCV: persistent anti-HCV and HCV RNA

treatment: PEG IFN-a-2b + Ribavirin for 6/12

  • 50% chance clearance

prognosis: slowly progressive

  • 85% remain chronically infected with mild hepatitis
  • children: 50-90% elevated LFTs, 40-60% positive RNA, cirrhosis 1-8%, HCC
71
Q

Hepatitis D

A

virus: hepatitis D RNA virus

transmission: blood

replication: requires HBV co-infection or superinfection

72
Q

Hepatitis E

A

virus: hepatitis E RNA virus

transmission: faecal oral

epidemiology: similar to HAV

clinical:

  • peak >15yrs
  • 3-8 weeks: lethargy, nausea and fatigue
  • usually self limiting
  • fatal in pregnant women and immunocompromised: fulminant liver failure
73
Q

Hepatoblastoma

A

incidence: 80% liver cancer in kids

  • usually <3yrs with abdominal mass

pathogenesis: immature liver precusor cells usually R lobe

investigations: elevated AFP, thrombocytosis, calcification

associated: FAP, prematurity, BWS, Meckel’s, Trisomy 18, cardiac anomalies, biliary atresia, Prader-Willi

metastasis: lung, CNS

treatment: resection, chemo, transplant

74
Q

Hepatomegally

A

neonate: >3.5cm BCM, size 4.5-5cm

child: >2cm BCM, size 6-8cm

75
Q

Hirschsprung’s

A

definition: aganglionic bowel from anal sphincter

incidence: 4:1 male to female

clinical:

  • no meconium 24 hrs then abdominal distension, vomiting
  • 80% present first 6 weeks
  • causes 15-20% neonatal obstruction
  • infrequently enterocolitis

AXR: no gas in rectum

diagnosis: full thickness rectal biopsy

76
Q

Hirschsprung’s

A

sporadic

cause: failure migration of nerve cells causing absence ganglionic cells in submucosal and myenteric plexus
epidemiology: 1/5000, M:F 4:1, assoc family history, T21, microcephaly, abnormal facies or palate
location: extends proximally from anus, 80% short segment (only rectosigmoid), 15% long segment (proximal to rectosig)
clinical: delayed mec >48hrs, distension, bilious asp, constipation, enterocolitis, toxic megacolon (proximal dilation and bacterial colonisation)
diagnosis: rectal biopsy, AXR
treatment: surgical resection aganglionic segment

77
Q

Hydrogen breath test

A

indication: bacterial overgrowth (eg short gut syndrome)

method: give patient CHO load and measure expired hydrogen

78
Q

Idiopathic neonatal hepatitis

A

causes: sporadic or familial

prognosis: generally good if well at 12 months

poor prognosis:

  • jaundice >6months of age
  • acholic stools
  • persistent hepatomegaly
  • severe inflammation on biopsy
  • familial occurrence
  • low GGT (disorder of bile acid transport/synthesis)
79
Q

Infliximab

A

drugs: monoclonal TNF antibody

use: Crohn’s, rheumatoid arthritis

side effects: infection, fever, hypotension

80
Q

Intestinal lymphangiectasia

A

definition: obstruction of lymphatic draininage of the intestine

cause:

- congenital: Turners, Noonan’s, Klippel-Trenaunay syndrome

- secondary: constrictive pericarditis, HF, abdominal TB, retroperitoneal malignancies

pathophysiology:

  • lymph rich protein leaks into bowel lumen

clinical:

  • diarrhea/steatorrhea, nausea and vomiting
  • peripheral oedema
  • chylothorax or chylous ascites

diagnosis:

  • hypoproteinemia, low albumin, IgA, IgG, IgM, transferrin, ceruloplasmin, clotting factors
  • loss of lymphocytes into gut (lymphopenia)
  • fat soluble deficiencies

investigations:

  • small bowel contrast – thick, nodular folds
  • endoscopy – scattered white spots
  • histopath – dilated lymphatics at tip of villi

treatment:

  • Low fat, high protein, medium chain triglyceride supplemented diet
  • octreotide
  • localised resection
81
Q

Intussusception

A

age: 6months -3yrs

  • uncommon < 3 months

clinical: sudden onset severe paroxysmal colicky pain

  • associated straining effort with legs

diagnosis: ultrasound

treatment: air enema

82
Q

Juvenille polyp

A

age: 2-10yrs

risks: 10-15% malignancy (multiple juvenille GIT polyps)

symptoms: bright red painless rectal blessing during or after defaecation

83
Q

Lactase deficiency

A

congenital lactase deficiency: rare (<50 cases), genetic, symptoms with lactose ingestion

primary adult-type hypolactasia (15% white adults)

  • decline lactase activity by 3 yrs

secondary lactase deficiency

  • post small bowel injury/infection/bacterial overgrowth​
  • cows milk protein enteropathy

diagnosis: H2-breath test or small bowel Bx and measuring lactase activity

84
Q

Liver and Prothrombin Time

A

Liver clotting factors: 2,5,7,9,10

  • PT normal abnormal until 80% synthetic capacity lost
  • Factor VII has short half life (6hrs) and senses rapid change in liver function
85
Q

Lynch syndrome

Familial non-polyposis colorectal cancer

A

incidence: 2-7% CRC patients

genetic: AD loss of expression of MSH2 causing DNA mismatch repair

clinical: increased risk colorectal cancer, endometrial cancer, digestive adenoma

diagnosis:

  • 3 or more relatives with CRC
  • 2 successive generations
  • 1 or more colon cancers <50 yrs
  • FAP excluded
86
Q

Malrotation

A

definition: incomplete rotation of the intestine in fetal development

clinical: volvulus in 1st week

  • bilious vomiting then abdominal distension
  • can progress to ischaemic bowel

diagnosis:

  • XR double bubble sign
  • US: malposition superior mesenteric vessels
  • upper GI contract study
87
Q

MALT lymphoma

A

definition: form of lymphoma involving the mucosa-associated lymphoid tissue

pathophysiology: 70-100% associated with chronic inflammation secondary to H.Pylori

diagosis: GI biopsy

treatment:

  • early stage disease curable with eradication H.Pylori
  • radiotherapy, chemotherapy
88
Q

Meckel’s Diverticulum

A

incidence: common congenital abnormality GIT

associations: major malformations of umbilicus, GIT, CNS, CVS

rule of 2’s:

  • 2% population
  • M:F 2:1
  • 2 feet from ileocaecal valve
  • 2 inches long
  • complications in 2% of patients

clinical

  • usually clinically silent
  • 50% present <10yrs painless lower GI bleeding
  • ulceration small bowel from acid secretion of ectopic gastric mucosa in the Meckel’s (25%)
  • chronic or acute
  • meckel’s can be lead point for intussusception/volvulus

diagnosis: nuclear med 99m technetium detects gastric mucosa (sensitivity 85-90%)

  • mesenteric arteriography: anomalous superior mesenteric artery branch feeding diverticulum
  • HRCT

management: resect if symptomatic/palpable abnormality

89
Q

Meckel’s formation

A
90
Q

Mild unconjugated hyperbilirubinaemia

in neonates

A

pathogenesis:

  • increased RBC breakdown: x2-3 production bilirubin
  • decreased UGT activity until 14 weeks
  • increased reabsorption due to sterile gut
91
Q

Multiple food allergy of infancy

A

incidence: rare, onset 1 week

allergens: breast milk, cow milk, soy, extensively hydrolysed formula

clinical irritability, feed refusal, vomiting, diarrhoea

treatment: AA formula

92
Q

Neonatal conjugated hyperbilirubinaemia

A

S: structural: biliary atresia, choledochal dyst, Caroli disease

M: metabolic: galactossaemia, CF, alpha-1-antitrypsin, bile acid transport defect

I: infection (TORCH/sepsis), idiopathic

T: TPN

E: endocrine (hypothyroidism/hypopituitarism)

93
Q

Neonatal formulas

A

hydrolized protein: peptides with added AAs and fat (primarily MCTs)

  • indications: cow milk/soy protein allergy, galactosemia

free AA acid formulas: non-allergic free AAs

  • indications: multiple food allergies, severe protein allergy, malabsorption, SBS, eosinophilic GI disorders
  • eg. neocate, elecare

low long chain fatty acid

  • indications: FA met disorder, fat malabsorption, chylothorax, lymphangiectasia
  • eg. enfaport, portagen, monogen
94
Q

Bilirubin metabolism

A

source: 80% bilirubin from breakdown Hb

metabolism:

  • bound to bilirubin
  • dissociates for uptake into hepatocytes
  • UGT catalyses conjugation with glucuronic acid for excretion in bile
  • excreted into bile and broken down bacterial enzyme urobilin
  • beta-glucuronidase deconjugates allowing reabsorption into entereohepatic circulation
95
Q

Neonates to hep B mother

A

mother: HepBsAg positive

treatment of infant:

  • immunise at birth then 2,4,6 and 12 months
  • hep B IVIg within 24 hrs of birth

testing: 9-15 months

96
Q

Niacin

(Vitamin B3)

A

deficiency: pellagra (dementia, dermatitis, diarrhoea)

  • aggression, dermatitis, insomnia, confusion, diarrhoea

use: essential for electron transport

97
Q

Non-alcohol Fatty Liver Disease

A

prevalence: 20% of obese children

  • most common liver disease in children

risk factors: obesity, insulin resistance

pathogenesis (spectrum)

  • fat accumulation in hepatocytes w/o inflammation
  • fibrosis (simple hepatic steatosis)
  • hepatic steatosis with necroinflammation (steatohepatitis) termed NASH

symptoms: may have RUQ pain, hepatomegally

diagnosis:

  • US: increased echogeneity
  • serum: elevated LFTs
  • biopsy

management: weight control

prognosis: 1/2 NASH progress to cirrhosis

98
Q

Oesophageal anatomy

A

Diameters

Cricopharyngeal sphincter: narrowest part 15cm from incisors

Constrictions at aortic arch (22cm), left main bronchus (27cm) and lower oesophageal sphincter

99
Q

Opthalmia Neonatorum

A

definition: neonatal conjunctivitis in the 1st month

pathogens/treatment:

neisseria gonorrhoea:

  • day 0-5
  • purulent discharge/inflammation
  • treat: bacitracin, 7 days IV ceftriazone

chlamydia trachomatis:

  • 5 days -2 weeks
  • more watery
  • treatment: AB drops, PO erythromycin to prevent resp disease

less common pathogens:

  • HSV-2, staph aureus,

complications: untreated may develop corneal ulceration

100
Q

Oral Rehydration Solution

A

definition: isotonic with equimolar concentrations of sodium and glucose

properties:

  • osmolality 200- 310 mmol/L
  • glucose <20 g/L (111 mmol/L)
  • sodium 60- 90 meq/L
  • potassium 15- 25 meq/L
  • chloride 50- 80 meq/L

mechanism water absorption: passive diffusion across osmotic gradient determined by

1. Na/H exchanger

2. electrochemical gradient

3. Na coupled transport

role of starch: increased non-absorbed CHO in colon is fermented into SCFA which are readily absorbed and increase Na reabsorption

101
Q

Osmotic diarrhoea

A

causes: presence of non-absorbable solutes in the gut

(e.g. lactose or fructose in intolerance)

pathophysiology:

  • intestinal damage (viral gastro)
  • reduced functional absorptive surface (coeliac)
  • defects in enzymes/nutrient carriers (lactase def)
  • decreased transit time (functional)

clinical:

  • STOPS when cease enteral feeds
  • volume SMALLER <200mls

investigations:

  • reducing substances PRESENT
  • stool pH <6
  • stool Na <60 (water drawn in dilutes)
  • stool osmotic gap >100
102
Q

Pancreatic function

A

function: secretes alkaline juice after eating

  • exocrine function under hormonal (secretin and CCK)/neuronal control

Stimulated:

  • secretin: released duodenal S cells in response to acid (stimulates pancreatic ductal cells)
  • CCK: released duodenal I cells response to fats + proteins (stimulates acinar cells/GB contraction)

inhibited:

  • somatostatin: duodenum/delta cells of pancreas

pancreatic enzymes:

  • trypsinogen/chymotrypsinogen
  • carboxypeptidase (protein)
  • elastases (break down the protein elastin)
  • lipase (triglycerides and fatty acids)
  • amylase (starch, glycogen, other carbs)
  • sterol esterase, phospholipase, nuclease

insufficiency causes maldigestion:

  • fat globules when >90% exocrine function lost

tests:

  • measuring pH/enzyme content of duodenal fluid after stimulation pancreas (e.g.meal/secretin/CCK)
  • serum trypsinogen
  • faecal fat ( >90% enzyme function lost)
  • faecal chymotrypsin/faecal elastase-1
103
Q

Pancreatitis

A

cause: 30% idiopathic, trauma, cholelithiasis

pathogenesis: premature activation of trypsinogen and pancreatic proenzymes causing autodigestion

diagnosis: serum lipase rises 4-8hrs, peaks 24-48 hrs, elevated 8-14 days

  • US: evidence of inflammation

complications: death, pseudocyst, abscess

treatment: NBM 24hrs, octreotide DOESN’T WORK

104
Q

Partially hydrolysed formula

A

e.g. pepti-junior, alfare

formula: di/tri peptides, AA, vegetable oil/MCT, carb maltdextrin (lactose free), low osmolarity

indications: fat malabsorption, intolerance whole protein, severe chronic diarrhoea

105
Q

Pathological jaundice

A

increased production (haemolysis)

  • autoimmune (ABO/Rh)
  • RBC membrane defects (spherocytosis/elliptocytosis)
  • RBC enzyme defects (G6PD, pyruvate kinase def)
  • sepsis

decreased clearance (defects UGT)

  • Crigler Najar/Gilbert
  • maternal DM
  • congenital hypothyroidism
  • galactossemia
  • structural (biliary atresia, alagille, caroli)

increased enterohepatic circulation

  • breast milk
106
Q

Pepsin

A

metabolism:

  • precursor pepsinogen secreted chief cells
  • converted by HCl acid to pepsin

function: breaks down proteins

107
Q

Peptic ulcer disease

A

incidence: uncommon

causes:

  • <10yrs: medications, more common gastric
  • >10yrs: H-pylori, duodenal
  • 20% idiopathic
  • secondary H.pylori, medications, Zollinger-Ellison, SBS

symptoms: pain (alleviated by food), NV, perforation, iron def, ITP, SIDS

investigations: H.pylori stool antigen assay, urea breath test, H.pylori IgG serology (low sens/spec), endoscopy

management: triple therapy (PPI+clarithomycin+amoxi/metro)

108
Q

Portal hypertension

A

definition: portal vein pressure >5mmHg or portal vein:hepatic vein gradient >10mm

symptoms: splenomegally (with thrombocytopaenia, anaemia, leukopaenia), varices (oeso, gastric, rectal), ascites, encephalopathy

causes: cirrhosis, pre-sinusoidal (portal vein thrombosis), post-sinusoidal (budd-chiari, venoocclusive disease)

management: variceal banding, transjugular intrahepatic portosystemic shunt (TIPSS)

109
Q

Primary alactasia (lactose intolerance)

A

incidence: very very rare 1:60,000

definiton: complete inability to digest lactose from infancy

pathophysiology: complete absence of lactase

110
Q

Primary sclerosing cholangitis

A

incidence: 70% associated with UC

  • complicates 1-3% UC

symptoms: jaundice, hepatomegally, cholestasis, fat malabsorption, bone disease

associated: cholangiocarcinoma (10-15%)

investigations: elevated LFTs (ALP highest), increased IgM, pANCA positive

ERCP/MRCP: short strictures in bile ducts with dilatation in between normal zones (beadin)

treatment: ursodeoxycholic acid, liver transplant

111
Q

Prokinetics

A

Metoclopramide

  • mechanism: D2 antagonist CNS and gut
  • side effects: restlessness, dystonic reactions

Erythromycin

  • mechanism: motilin receptor agonist
  • side effect: prolonged QT, c.difficile, pancreatitis
112
Q

Protein losing enteropathy

A

3 main causes:

1) Mucosal disease with protein loss across mucosa
eg. IBD, ulcer, lymphoma
2) Lymphatic obstruction causing protein rich chyle
eg. primary intestinal lymphangectasia, secondary obstruction due to cardiac disease, infection, neoplasm
3) Idiopathic alteration in mucosa permeability
eg. gastroenteritis, coeliac, Zollinger Ellison, SLE

Stool alpha 1 antitrypsin is a marker (resistant to proteolysis and degradation in the bowel)

113
Q

Proton Pump Inhibitor

A

drugs: omeprazole, pantroprazole

pharmacology: irreversibly/noncompetibly block parietal cell H/K ATPase and decrease HCC secretion

use: GORD, PUD, gastritis

114
Q

Reducing sugars

A

definition: sugars capable of reducing oxidizing agents in alkaline solution

  • e.g. glucose, fructose, maltose, lactose
  • non reducing sugars: sucrose
115
Q

Refeeding syndrome

A

symptoms:

  • hypophosphataemia, hypokalaemia, hypomagnesia, hyperglycaemia
  • vitamin depletion
  • volume overload/oedema: Na/fluid reabsorption in kidneys
    mechanism: surge of insulin pushes/PO4/K/Mg into cells
    complications: CVS , resp failure (hypophosp), muscular weakness, raised liver transaminases (increased fat deposition), diarrhoea, neurological
    prevention: slow feeding, careful monitoring, electrolyte replacement
116
Q

Rotavirus

A

definition: dsRNA virus family reoviridae

clinical: foul smelling non bloody diarrhoea for 3-8 days

  • associated nausea, vomiting, fever
  • secondary lactose intolerance for weeks

pathophysiology:

Day 1: infects enterocytes of villous epithelium jejunum/ileum causing cell damage and loss of fluid/salt

Day 2-5: adjacent villi fuse reducing SA

Day 6-10: normal architecture

  • loss of brush border enzymes with loss ability to digest complex sugars/CHO causing lactose intolerance
  • secretory diarrhoea via non-structural glycoprotein NSP4 enterotoxin: calcium ion dep chloride secretion and disrupts water reabsorption
  • enteric nervous systemic activation wiuth secretion

diagnosis: antigen stool immunoassay

  • 1-4 days 94% detected
  • 4-8 days 76% detected
  • >2 weeks occassional
117
Q

Salmonella typhimurium

A

definition: gram negative rod of enterobacteriacae family

source: contaminated food, hands, water

clinical:

  • fever diarrhoea, anorexia, headache, stomach pain, vomiting
  • mucousy/bloody stool
  • 5% develop bacteraemia/meningitis/osteomyelitis (greater<3m)

pathophysiology:

  • incubation 12-36 hours, duration 4-7 days
  • enterocolitis with diffuse mucosal inflammation/edema with microerosion/abscesses
  • attaches epithelial cells via fimbriae and invades cells by bacterial mediated endocytosis and remain in phagosome
  • induce inflammatory response with IL8 secretion, neutrophil recruitment and pro-inflammatory mediators

diagnosis: faecal PCR

treatment: fluoroquinolones

118
Q

Schwachman Diamond Syndrome

A

Autosomal recessive chromosome 7

Skeletal (>2yrs), Haematological

Normal sweat chloride

30% develop myelodysplastic syndrome

Neonatal sepsis secondary to neutropaenia

Lipomatous changes in pancrease: 50% pancreatic insufficiency age 4-5yrs

119
Q

Secretory diarrhoea

A

Causes:

  • electrolyte and water secretion into intestinal lumen
  • stimulates Cl secretion or inhibition of NaCl absorption

bacterial toxins: bacillus cereus, clostridium perfringens, Enterotoxigenic Ecoli, cholera, giardia lamblia, crytosporidium, rotavirus

Feeds: CONTINUES when cease enteral feeds ***

Volume: LARGE >200mls/day

Features:

  • NO reducing substances
  • pH >6
  • Stool Na >90
  • Osmotic gap <50
120
Q

Shigellosis

A

definition: shigella bacteria gram negative rod

source: food, faecal oral route

clinical: pain, fever diarrhoea with mucous/pus/blood, mucosal ulcerations

  • assoc seizures

timing: onset 12-96hr lasting 5 to 7 days

pathogenesis:

  • attach to and penetrate intestinal mucosa causing inflammation/desquamation
  • spread to adjacent cells via fimbriae
  • induce inflammatory reaction

treatment: bactrim if necessary

121
Q

Short Bowel Syndrome

A

Loss >50% bowel

Generalised malabsorption disorder of specific nutritional def

Proximal jejunum main site CHO, protein, Fe, water soluble vitamin absorption

Fat over large length small bowel

Symptoms: watery diarrhoea, cholestatic liver disease, gastric hypersectrion, ulcers, bacterial overgrowth, nutrient/vitamin def, enteric hyperoxaluria (calcium binds fat in steatorrhoea) causing kidnet stones

Treatment: TPN, trophic feeds

122
Q

Short bowel syndrome

A

0.02-0.1% live births

80% develop in neonatal period

Most common cause of intestinal failure (unable to achieve complete nutrition without supplementation)

Malabsorption marcro/micronutrients caused by massive resection small intestine

Causes: NEC (35%), mec ileus (20%), abdominal wall defects (12.5%), intestinal atresia (10%), volvulus (10%)

Mortality 20-40%

Management: PN, enteral nutrition (high fat, complex CHO), H2 blockers, vitamins, serial transverse enteroplasty

123
Q

Staph food poisoning

A

onset: 30-8hrs post food

mechanism: staph aureus toxin

clinical: severe vomiting +/- diarrhoea

  • resolves 24-48 hours
124
Q

Stool osmotic gap

A

equation: 290-2(Na+K) = 50-100mosm/kg

*290 value of plasma osm

Interpretation

  • if >100mosm/kg: osmotic diarrhoea
  • if <50mosm/kg: secretory diarrhoea

NB. Sodium>70mmol/l suggestive of secretory diarrhoea

125
Q

Sucrase-Isomaltase Deficiency

A

definition: rare AR absence of sucrase in small intestine

clinical:

  • diarrhoea, abdominal pain, poor growth with exposure to sucrose or glucose (non lactose formula/pureed food)

diagnosis:

  • H2 breath test
  • NO reducing substances are present (sucrose isn’t a reducing sugar)
  • direct enzyme assay on small bowel Bx

treatment: dietary restriction

126
Q

Sulfasalazine

A

drug: sulfapyridine and mesalamine

pharmacokinetics:

  • prodrug: 1/3 absorbed small intestine, 2/3 colon (splits into 5-ASA and SP)

use: Crohn’s, ulcerative colitis

toxicity: anorexia, nausea, vomiting, sulfur toxicity

127
Q

Technetium pertechnetate scan

A

mucus secreting cells of ectopic gastric mucosa take up pertechnetate

sensitivity 85%, specificity 95%

128
Q

Toddler’s diarrhoea

A

Many BAs per day but otherwise well + thriving

Daily, painless >3 large unformed stools, >4 week duration

Rx: trial lactose and low fructose (low fruit juice) diet

129
Q

TPN related neonatal cholestasis

A

18% to 67% of infants who receive prolonged courses of PN develop liver injury and cholestasis

RF: low birthweight, long PN therapy, sepsis, bacterial overgrowth of the small intestine, and intestinal failure

Cause: The soybean-based lipid emulsion component of PN.

Treat: enteral feedings as early as possible to stimulate bile flow, gallbladder contraction, and intestinal motility. Ursodeoxycholic acid is theoretically of benefit by stimulating bile flow; however, there is no evidence of its efficacy in PNAC.

130
Q

Tracheo-oesophageal fistula and oesophageal atresia

A
  • TOF is a common congenital anomaly of respiratory tract
  • 1 in 3500
  • Typically occurs with oesophageal atresia
  • OA and TOF are classified by anatomy
  • Type C – account for 84%
  • Defect in lateral septation of the foregut into oesophagus and trachea
  • Associated with VACTERL (vertebral anomalies, anal atresia, cardiac anomalies, TE = tracheoesophageal fistula, renal anomalies, limb anomalies)

Clinical features

  • Depends on presence or absence of OA
  • In cases with OA (95%) – polyhydramnios occurs in 2/3rds of pregnancies
  • However many are not detected antenatally
  • Infants with OA because symptomatic immediately after birth
  • Infants with H type –
    • May present early if defect is large with coughing and choking associated with feeding as milk is aspirated
    • However smaller defects may not be symptomatic in newborn period
    • Can be diagnosed from 26 days to 4 years
    • Prolonged history of mild resp distress associated with feeding and recurrent pneuomina

Diagnosis

  • Pass catheter into stomach: not passed further than 10-15cm
  • CXR: catheter curled up in upper oesophageal pouch
  • Distal TOF can be seen on lateral chest CXR – both views will show gas filled GIT
  • For isolated TOF – upper GIT series with barium & endoscopy & bronchoscopy

Management

  • Surgical ligation of fistula
  • With OA need to anastomose oesophagus

Outcome

  • For isolated TOF – generally good
  • With AO and TOF it is more guarded and depends on associated abnormalities
  • Higher mortality if cardiac disease present
  • Complications – anastomotic leak, oesophageal stricture, recurrent fistula
  • GORD and aspiration
131
Q

Liver cysts

A

usually asymptomatic

types: simple/solitary, polycystic, parasitic (hydatid cyst), neoplastic (cystadenoma, cystoadenocarcinoma, mets), duct related (Caroli, bile duct dupication), false cyst

132
Q

Transient Hyperphosphatasemia

A

definition: elevated ALP in absense liver/bone disease

diagnosis: 5x normal and decreases <3 months

pathogenesis: unknown

investigations: Ca, Ph, ALT, AST, GGT, bilirubin, vit D, PTH, urea, Cr

133
Q

Treatment neonatal jaundice

A

Phototherapy

  • isomerisation to lumirubin (more soluble/less toxic)
  • fluorescent blue light

Side effects: dehydration, rashes, loose stool, hyperthermia, bronze baby

Exchange transfusion

  • replace 85% circulating RBCs to decrease bilirubin by 50%
  • also infuse 1g/kg albumin
  • above threshold OR signs of kernicterus

Side effects: infection, DIC, GVHD, thombosis, EUC abnormalities

134
Q

Triple therapy

A

PPI, clarithromycin and amoxycillin

135
Q

Ulcerative colitis

A

incidence: 11/100,000, M>F 1.8:1

pathology: contiguous large bowel mucosal, NEVER PERIANAL LESIONS

risk factors: twice as common in non-smokers

clinical:

- diarrhoea with bleeding/mucous

  • abdominal pain
  • urgency, tenesmus
  • lethargy, anorexia, fever
  • pyoderma gangrenosum (50%), erythema nodosum (4%)

Fulminant colitis: >5 bloody stools per day

complications: increased malignancy 8-10yrs post diagnosis, toxic megacolon

diagnosis: pANCA (70%), ASCA

treatment: 5-ASA, steroids, immunomodulators, colectomy (25% within 5 yrs dx)

136
Q

Unconjugated jaundice

A

Causes:

- breast milk: benign, onset d3-5, persists >1wk, high levels beta glucoronidase causes deconj of bilirubin

- breast feeding

- haemolysis

- Crigler-Najjar

- Gilberts

137
Q

Vibrio Cholerae

A

Toxin: 5 binding (B) subunits and 1 active (A) subunit

  • B subunits bind GM1 ganglioside receptors on the small interstinal mucose
  • A subunit enters cells and activate adenylate cyclase, increasing cAMP, blocking absorption of NaCl by microvilli
  • increased secretion Cl/water by crypt cells
138
Q

Vitamin A deficiency

A

causes: poor intake in developing countries, fat malabsorption

clinical:

  • ocular: night blindness, retinopathy, xeropthalmia
  • skin: hyperkeratosis, destruction hair follicles
  • other: poor bone growth, infections, abnormal tooth enamel development
139
Q

Vitamin B1 (thiamine)

A

deficiency: beriberi

  • weight loss, emotional distubance, Wernicke’s, weakness, arrythmia, weakness
140
Q

VItamin B12 (cobalamin)

A

source: meat/dairy

stores: 50% liver, 3 yrs until deficiency develops

absorption

  • B12 unbound to protein and binds R factors in stomach
  • B12 unbound R factors by pancreatic proteaases and bind to IF
  • absorbed terminal ileum as B12-IF complex

plasma: bound to transcobolamins (TC I, II, III)

  • TC II: most important, carries B12 to liver/BM, reflects tissue stores

cells:

  • receptor mediated endocytosis into cells
  • converts proprionyl CoA to succinyl CoA
  • transfers methyl group from methylTHF to homocysteine to form methionine
141
Q

Vitamin B12 deficiency

A

congenital causes:

transcobalamin deficiency: AR

  • failure to absorb/transport B12 with normal serum B12 because T I/III unaffected
  • manifests first weeks of life
  • treatment: large parenteral doses B12

clinical:

  • anaemia, glossitis, stomatitis, jaundice, bleeding, infections
  • neurological: peripheral neuropathy, optic atrophy, MR, subacute cord degeneration

diagnosis:

  • macrocytic anaemia >100, large/ovoid RBCs, anisocytosis, poikilocytosis, low reticulocytes
  • low B12, normal folate, increased urine methylmalonic acid/homocysteine
142
Q

Vitamin B2 (riboflavin)

A

deficiency: ariboflavinosis

clinical: glossitis, angular chelitis, light sensitivity, dermatitis

143
Q

Vitamin B6 (pyridoxine)

A

Deficiency: irritability, seizures, anaemia

144
Q

Vitamin C deficiency

A

causes: anorexia, neurodevelopmental delay

clinical: (scurvy)

  • skin: hyperkeratosis, perifollicular haemorrhage, petechiae, ecchymoses, gingivitis

other: fatigue, arthalgias, anorexia, neuropathy, dyspnoea, hypotension, anaemia, impaired wound healing

145
Q

Vitamin D

A

Deficiency: Rickets (up ALP), hypocalcaemia, osteomalacia, infantile tetany

  • risk factors: poor sunlight/intake, exclusive breastfeeding, maternal def, prematurity, obesity, CRF, malabsorption, liver failure, drugs (anticonvulsants, antiretrovirals, steroids, ketoconazole)

Excess: hypercalcaemia, azotemia, poor growth, NVD, calcinosis

146
Q

Vitamin E deficiency

A

causes: fat malabsorption

clinical:

  • spinocerebellar syndrome: ataxia, hyporeflexia, loss of proprioreceptive/vibratory input
  • haem: haemolytic anaemia

treatment: reversible<4yrs

147
Q

Vitamin K

A

Deficiency: haemorrhage (factors II, VII, IX, X)

148
Q

Wilson’s disease

A

incidence: 1/30,000

genetics: AR, chromosome 13 ATP7B

mechanism: defect in copper excretion with accumulation in liver/brain

symptoms:

  • ocular: kaiser-fleisher rings (50%), sunflower shaped cataracts
  • GI: abdo pain, jaundice, hepatomegaly, portal HTN
  • neurological sx in 20’s: gait, tremor, dysarthria, basal ganglia copper deposition
  • other: haemolytic anaemia, renal failure

investigations: low serum copper, low plasma ceruloplasmin, elevated transaminases AST>ALT, low ALP, raised urinary/liver copper, thrombocytopaenia, coagulopathy

prognosis: HCC, liver failure

149
Q

Zinc deficiency

A

causes: crohn’s CF, sickle cell, liver disease, acrodermatitis enteropathica (congenital defect in absorption)

clinical:

  • erythemtous/vesiculobullous rash to genitals and cheeks
  • diarrhoea
  • poor growth
  • alopecia
  • decreased ALP
150
Q

Crohn’s disease

A

incidence: 5/100,000 (25% <18 years)

pathology: GI tract, patchy, transmural, perianal disease, oral lesions (10%)

clinical:

  • abdominal pain, diarrhoea, rectal bleeding
  • fevers, weight loss
  • pyoderma gangrenosum

complications: strictures, fistulas, abscess

treatment: enteral tx, 5-asa, steroids, azathioprine, MTX, antibiotics, TNF mono Ab

151
Q

Metabolism azathioprine

A

metabolism:

  • 0.3% have low TPMT activity
  • 11% intermediate TPMT activity

high levels TGN: increased therapeutic index/BM suppression

high 6-MMP: increased hepatotoxicity

FRACP Exam (23 decks)

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