GIT Flashcards
Achalasia
failure of smooth muscle fibres to relax → cause lower oesophageal sphincter to remain CLOSED
- due to failure of inhibitory ganglion cells (which normally cause oesophageal dilatation)
Clinical features
- dysphagia
- nocturnal cough
- FTT
Dx
barium swallow or endoscopy
Rx
myotomy
pneumatic dilatation of LES
Chronic diarrhoea definition
↑ frequency +/or volume of stool for AT LEAST 2 weeks
NB: chronic non-specific diarrhoea (CNSD) most common - often due to transit time “toddlers diarrhoea”
chronic non-specific diarrhoea (CNSD)
“toddlers diarrhoea”
“fruit juice diarrhoea”
“peas and carrots” diarrhoea
Child is otherwise well and thriving normally
no physical redflag signs eg: clubbing, oedema, pallor (anaemia), jaundice, wasting, pot belly etc
Normal stool microscopy
- no fat globules or fat crystals
- no blood or pus cells
- giardia or cryptosporidiae
normal coeliac screen → TTG (tissue transglutaminase Ab)
Types of diarrhoea
mechanisms
OSMOTIC - sugar malabsorption or intolerance
1’ causes
- fructose (fruit juices)
- congenital deficiencies
2’ causes(interfere w glucose transporter, bacterial overgrowth)
eg: short gut, enteropathy, bacterial overgrowth, severe allergies, immune deficiency
NB: osmotic diarrhoea stops when pt is NBM, secretory diarrhoea continues, regardless of food intake
∴ think of secretory diarrrhoea when Hx of dehydration and electrolyte disturbances
SECRETORY
infective - e.coli, cholera (rice water - will die if dont rehydrate)
fat malabsorption: fatty acids + bile acid cause colonic secretion
laxative abuse
rare tumours - VIPomas, neuroblastomas (catecholamine), medul thyroid Ca,
congenital villous atrophy
congenital chloride diarrhoea
INFLAMMATORY (tissue damage due to immune cell activation)
- infection: campylobacter, salmonella, yersinia, amoebic dysentry, c.diff
- inflammatory bowel disease: crohn’s, UC, eosinophilic enteritis, immune deficiency syndrome incl chronic granulomatous disease
BLOOD + PUS = HALLMARK FEATURE
GVHD
Causes of fat malabsorption
1) Maldigestion
pancreatic insufficiency (CF, chronic pancreatitis)
- fat globules in stool
2) inadequate micellar solubilisation of digested fat
eg: bile acid deficiency in cholestatic liver disease eg: biliary atresia
- fat globules in stool
3) impaired mucosal absorption of fat
- mucosal disease eg: coeliac
- see fatty acid CRYSTALS rather than globules
4) impaired t/f of fat from enterocytes → lymphatics
eg: lymphoma, lymphangiectasia, abetalipoproteinaemia
Consequences of fat malabsorption
Fat soluble vitamin deficiency (ADEK)
Calorie deficiency + FTT
steatorrhoea (bulky, fatty, smelly stools)
sarcopenia
osteoporosis
how to ix for fat malabsoprtion
CCK/secretin stimulation test (NJ tube measure panc fluid) → no longer available due to secretin shortage
faecal fat balance studies - 5 day food diary to determine fat intake - 72hr fat excretion measurement - >7% excretion = fat malabsoprtion → this is done in CF pts
faecal elastase assay
labelled triolein H breath test
PERT (pancreatic enzyme replacement Rx)
- improves digestion, symptoms, nutritional status + QoL
PERT dosage 5000 lipase units/kg/day\
Ix
stool MCS/OCP/fat globules or fatty acid crystals/faecal calprotectin
FBE, iron studies, B12/folate
LFT - ? low alb
coeliac serology (IgA lvls, TTG, EMA) NB: coeliac serology alone is NOT reliable in very young/pre-school age ∴ would go onto endoscopy (modified marsh criteria >1 = coeliac)
Hx/RF/Dx coeliac disease
FTT, diarrhoea, steatorrhoea, anaemia, hypoalbuminaemia, +FHx
effects 1-3% of population
RF for coeliac (ALL NEED SCREENING) 1st degree +FHx T1DM Downs syndrome autoimmune thyroiditis autoimmune hepatitis
serology (sensitive + specific):
IgA: anti-tTG (tissue transglutaminates),
4x ULN false +ve, but 10 x ULN - pretty diagnostic
IgG: DGP - deamidated antigliadin Ab
total IgA lvls
HLA DQ2 + DQ8
duodenal Bx changes
gastroenteritis definition + epi
vomiting/fever (often → then) diarrhoea
diarrhoea = 3+ loose stools/24hrs for <14 days
now less due to rotavirus vaccination
first infection @ 3-36mo likely most severe
peak in mid to late winter
Causes of gastroenteritis
VIRUS (70%)
rotavirus
- immunity not lifelong, incubation 1-3 days then profuse early vomiting, temp >39 in 1/3 of pt
- penetrates SB wall + causes villus destruction ∴ 5-7 days for bowel to reform
adenovirus (epidemics, rash may be prominent)
norovirus (epidemics, schools, camps, childcare)
-parechovirus: can cause sepsis likely illness in neonates + young infants (esp <3mo)
– macpap rash, enchephalitis, myoclonic jerks, hepatitis, distended abdo, irrititabiltiy like in pain, volvulus, intussusception, bowle ischaemia → needs ACTIVE supportive Rx
- others: enterovirus, , astrovirus)
BACTERIA (15%) Campylobacter - wide variety of animal hosts, esp chicken - abdo pain prominent Salmonella - contaminated food (summer epidemics) - mucosal invasion → colitis prominant - WCC in stool - prolonged excretion of bacteria E.coli (ETEC etc) Shigella S typhi cholera Yersinia (reputation for mimicking appendicitis)
PARASITES
giardia
cryptosporidium
others eg: entamoeba
is it viral or bacterial GE?
Viral/rotarvirus - tenders to be autumn/winter - watery diarrhoea without blood \+/- vomiting low grade temp anorexia 90% < 5yo
bacterial blood + mucous in stool \+/- vomiting high fever may have Hx recent travel foodborne? HUS - ARF, low plt, anaemia w MAHA
Dehydration clinical picture
NO single symptom reliably predicts dehydration ∴ take all info into account
- wet nappies
- fontanelle
- skin turgor
- CRT
- tachycardia
mild 3% reduced UO thirst dry MM mild tachycardia
moderate 5% body weight = NG or IV dry MM ↑ HR abnormal resp pattern lethargy reduced TT sunken eyes
severe 10% above signs plus poor perfusion - mottled, cool, slow CRT altered conscious state thready pulse + marked tachycardia
IV/IO w 20ml/kg stat dose
important DDx GE (ie: vomiting, fever, diarrhoea)
and red flag symptoms to prompt consideration of other causes
acute appendicitis strangulated hernia intususception + other causes BO (malrotation/volvulus) UTI meningitis other causes of sepsis any cause of raised ICP DKA inborn errors of metabolism inflammatory bowel disease HUS
blood in stool or vomit bile in vomit (bowel obstruction) vomiting but no diarrhoea diarrhoea then vomiting headache very high temp >39 young child esp <3mo severe abdo pain/distension
Ix in gastro if moderate to severe dehydration
bloods (FBE/UEC/CRP/LFT) + BSL +/- blood culture if >38.5
stool MCS + PCR
consider
urine MCS
CXR, AXR, USS, air enema
Mx dehydration
MILD
- offer ORS (Na + glucose transported in equimolar ratio AKA for 1 Na, 1 CHO transported) in frequent, small volumes aiming
~0.5ml/kg/5min
- document (10ml syringe or hydrolyte iceblock)
ORS - hydralyte/gastrolyte
NB: apple juice/soft drinks/sport drink has high CHO low Na high osmolarity so makes diarrhoea worse
MODERATE
- aggressive + diligent PO rehydration
- NG hydration w gastrolyte (60mmol/L Na
- RAPID = over 4 hrs @ 10ml/kg/hr (DON’T use if <6mo or medical condition where at risk of fluid overload)
- STANDARD = 24- 48hr period
- dont use if risk of BO, reduced GCS
- if IVT - 10ml/kg of 0.9% NaCl + 5% glucose i over 4 hrs OR if over 24-48hrs add 20mmol/L KCl
dont use rapid rehydration over Q4Hrs if child <6mo, altered LOC, child is shocked, abnormal Na+
severe
- 20ml/kg NACL bolus
REMEMBER THAT IF CLINICAL STATUS DOESNT IMPROVE W REHYDRATION THINK OF OTHER Dx/causes
NB: dont use fluids with less conc Nacl than 0.9% as higher rate of cerebral oedema
HOW TO: standard IV rehydration to provision of maintenance fluids - usually over 24hrs
calculate maintenance + deficit FROM NOW (dont include fluids already given for resus)
- monitor GA, HR, UO, ongoing losses or fever @ intervals of Q4-6H
- majority of kids dont need more than a 5% deficit rehydration in 1st 24hrs
MAINTENANCE fluid calculation
1st 10kg = 100ml/kg/day = 4ml/kg/hr
2nd 10kg +50ml/kg/day = 2ml/kg/hr
subsequent kg +20ml/kg/day = 1ml/kg/hr
Meds in gastroenteritis
no role for anti-motility or anti-diarrhoeal agents
ondansetron ok, (dont use promethazine or prochlorperizine due to risk of dystonic reactions)
probiotics + zinc may have some clinical benefits - introduce when normal diet is reintroduced
antibiotics RARELY indicated
When to admit child with gastro into hospital?
severely dehydrated at risk of dehydration - age <6mo - high freq watery stools. or vomits, minimal PO intake, worsening symptoms - high risk complications eg; diaetes, renal failure, poor nutrition - Dx in doubt or possible surgical Dx - parent or carer unable to Mx at home - unsuccessful at oral rehydration
NB: early reintroduction of food has nutritional advantages
small frequent breast feds still ok
no advantage to regrading feeds
How to make acute diarrhoea chronic by accident
- restrict dietary intake + elimination diets
- give high volume juices, cordials etc (apple juice is the WORST culprit as high osmolality)
use ABx
use. anti-diarrhoeals
lactose intolerance can occur w GE but most children dont need change diet
tell me re: rotavirus vax
Rotavirus vaccination
- live attentuated vax
@ 2 mo /4mo /6mo
reduces risk of severe dz by 85 - 100%, risk of any rotavirus by 70%
S/E small risk of intususception (no catch up doses)
Jaundice in neonates
Overview
jaundice beyond second week of life → need to look for conjugated billirubinaemia (which is NEVER physiological)
- always need to have urgent Ix for biliary atresia as early Dx = vital for good outcomes
breastmilk jaundice = diagnosis of EXCLUSION
– provided total bili not >340 (but depends on age or gestation)
Hx
- FHx
O/E
- jaundice, hepatomegaly, splenomegaly, dysmorphic detures
- inspect urine + stool colour (PALE white chalky stool, dark urine)
- dip urine
- FBE + film, TFTs
- check newborn screen ring up!)
- IRT = CF
- Gal-1-P galactosaemia
- (doesnt cause jaundice) PKU
- TSH - hypothyroidism
prolonged unconjugated hyperbilirubinaemia
raised total bili
unconjugated bili fraction is <30umol/l ( +/or <20% of total)
due to either:
1) increased production
- haemolysis: Rh, ABO incompatibility
G6PD, pyruvate kinase deficiency, HS, HE, thalasaemia + other haemoglobinopathies
- extra-vascular blood eg: cephalohaematoma
- polycythemia from DM mother
2) reduced excretion
- hypothyroidism
- UTI
- dehydration, delayed mec passage
- familial
- Crigler-Najjar syndrome
- breast milk jaundice
conjugated hyperbilirubinaemia causes
+ Ix + Mx
cholestasis of newborn
infections (TORCHS)
- toxoplasmosis, rubella, CMV, Herpes, Syphilis
- enterovirus (echo, coxsackie)
- UTI, sepsis
- Hep B +C
metabolic diseases
- CF
- A1AT deficiency
- galactosaemia
- glycogen storage disease
- tyrosinaemia
- neonatal iron storage disease, other genetic liver dz
- panhypopit
biliary diseases
- biliary atresia (most common cause)
- alagille’s syndrome (intrahepatic biliary hypoplasia)
- choledochal cyst
- pigment stone obstruction
- lots of others
Ix
LFT
Ultrasound
DISIDA scan (nuc med scan taken up by liver - if no excretion into biliary tree more likely)
exclude infectious + metabolic causes
operative cholangiogram + liver Bx (gold standard for biliary atresia)
liver Bx
Mx
portoenterostomy (kasai procedure)
- better results if done @ <60 days old
- Roux-En Y
- prognosis
- 1/3 good bile drainage, no early complications good prognosis
- 1/3 intermediate prog (hepatic fibrosis → portal HTN → transplant 5-10
- 1/3 poor bile drainage → need liver transplant (in 1st 18 mo)
liver transplantation - >50% liver transplants
Biliary atresia
1:10,000 ( most common cause of cholestasis in infants)
unknown cause
inflammatory process of extra& intrahepatic bile ducts → fibrosis
→ other defects in 20%: cardiac, vascular, splenic
Jaundice work up in older child eg: 9yo
Hx:
contact Hx: travel, family, school
PHx + FHx: jaundice, gallstones, liver disease (wilson’s, AIH)
ingesting uncooked shellfish eg: oysters 2-6 weeks prior (eg: hep A)
recent injection, surgery, blood products, tattoos
recent drugs: eg: sulpher meds, fluclox, panadol, cocaine
ingestion of wild mushrooms
O/E: signs of CLD? - growth failure, clubbing, leukonychia, palmer erythema, spider naevi, splenomegaly encephalopathy? - hyperreflexia, clonus, flap - level of consciousness
organomegaly, KF rings
?are they in acute liver failure?
check coags
- if coags off, give IV vit K → if doesnt correct in Q6H → in liver failure
encephalopathy late sign
ascites also occurs late
DDx hepatitis
infections
- hep A/B/C/E
- EBV/CMV
- adenovirus
- HHV6, parvovirus
- VZV, HSV
- enterovirus (coxsackie, echovirus)
drug reactions (idiosyncratic eg: sulphur drugs, antiepileptics, halothane, ecstacy or dose related → panadol) toxins eg: shrooms
wilsons
autoimmune
budd chiari
Ix hepatitis
FBE UEC LFT CMP coags
viral serology
wilson dz
- serum Cu + caeruloplasmin (typically low, also acute phase reactant)
- opthal ?KF rings
- 24hr urinary Cu +/- penicillamine challenge
- liver Bx
- genetics
AIH
- autoAbs (ANA, SMA, LKMA, IGs)
Bx
CLD Mx
Mx portal HTN Cx - variceal bleeding, ascites, hypersplenism (pancytopenia)
nutritional, fat soluble vitamin deficiency, hypoalb
sepsis (immunosurpressed) immunisation - pneumococcus
hepatorenal syndrome, encephalopathy, hepatopulmonary syndrome
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