Gastroenterology Flashcards
8 causes of vomiting
- Overfeeding
- Gastro-oesophageal reflux
- Intestinal obstruction: Pyloric stenosis (projective vomiting), Intussusception, Inguinal hernias, Hirschsprung, Malrotation, Atresia, Volvulus
- Sepsis
- Gastritis or gastroenteritis
- Appendicitis
- Infections such as UTI, tonsillitis or meningitis
Red flag features of vomiting
- Projectile or forceful vomiting (pyloric stenosis or intestinal obstruction)
- Vomiting at end of paroxysmal cough (whooping cough)
- Bile stained vomit (intestinal obstruction)
- Haematemesis (peptic ulcer, oesophagitis or varices)
- Abdominal distention (intestinal obstruction)
- Reduced consciousness, bulging fontanelle or neurological signs (meningitis or raised intracranial pressure)
- Respiratory symptoms (aspiration and infection)
- Blood in the stools (gastroenteritis or cows milk protein allergy)
- Signs of infection (pneumonia, UTI, tonsillitis, otitis or meningitis)
- Rash, angioedema and other signs of allergy (cows milk protein allergy)
What is difference between GOR and GORD in infants
- GOR: gastric contents into oesophagus (+/- regurg, vomiting). [Normal for baby to reflux feeds. Not a problem if normal growth and otherwise well. Usually stops after 1 year.]
- GORD: presence of troublesome symptoms and/or complications of persistent GER.
[Under year doesn’t usually experience same symptoms as children over 1 year/adults: heartburn, acid regurgitation, epigastric pain, bloating.]
Cause of GOR in infants
- immaturity of lower oesophageal sphincter leads to inappropriate relaxation.
- predominantly fluid diet, mainly horizontal posture, short intraabdominal length of oesophagus
Problematic features of GORD
- faltering growth/failure to thrive/ IDA
- oesophagitis +/- stricture
- apnoea
- aspiration, wheezing
- seizure like events
Treatment of uncomplicated reflux in infants (under 1)
- parental reassurance
- small, frequent meals
- Keeping baby upright
Treatment of problematic GORD
- gaviscon
- thickened milk
- ranitidine (h2 receptor antagonist)
- omeprazole (proton pump inhibitor)
- nissen fundiplication
What age does malrotation, pyloric stenosis and intussusception typically present?
malrotation: 24 hours, pyloric stenosis: 4 weeks, intussusception: 6 months
Why is color of vomiting important in diagnosis and what are the causes of bilious vomiting?
- If non-bilious then caused by obstruction above ampulla of vater (junction of bile ducts + duodenum)
- bilious: malrotation/volvulus, hirschsprung, intestinal atresia, intussusception (+/-, depend on site) , strangulated hernia
- non-bilious: pyloric stenosis, intussusception (+/-), inhaled foreign body
Pathology of pyloric stenosis
hypertrophy of the pyloric muscle causing gastric outlet obstruction. Increasing peristalsis as tries to push into duodenum but eventually so powerful pushes food back up and causes projectile vomit.
Features of pyloric stenosis
- presents 2-7 weeks
- projectile, milky, vomiting
- hungry, dehydrated, thin, pale baby. Failure to thrive
- firm, round mass in upper abdomen. ‘Olive-like’
What does blood gas analysis show in pyloric stenosis (common exam q)
- hypocholoraemic (low chloride) metabolic alkalosis
- low plasma sodium (hyponatremia) and potassium (hypokalaemia)
- due to vomiting of Hydrochloric acid from stomach
How to tell metabolic acidosis/alkalosis against respiratory acidosis/alkalosis
pH: Low = acidodis, High = alkalosis
HCO3- High/Low = metabolic alkalosis/metabolic acidosis
CO2 High/Low = respiratory acidosis/respiratory alkalosis
Diagnosis and treatment of pyloric stenosis
Abdo US. Rehydration + correction of electrolyte imbalance followed by Pyloromotomy surgery.
Character of abdo pain in: Appendicitis Intusussception Bowel obstruction Testicular torsion
- Appendicitis: central abdominal pain spreading to the right iliac fossa
- Intussusception: colicky non-specific abdominal pain with redcurrant jelly stools
- Bowel obstruction: pain, distention, absolute constipation and vomiting
- Testicular torsion: sudden onset, unilateral testicular pain, nausea and vomiting
What age is acute appendicitis very unlikely
Under 3 years old
Presentation of appendicitis
- Symptoms: vomiting, abdo pain - central and colicky then right iliac fossa, fever, persistent tenderness with guarding in right iliac fossa
Mx of appendicitis - uncompl + complic.
Uncomplicated: appendicectomy
Complicated: perforation - fluid resus, IV Abx, then appendicetomy
What is non-specific/functional abdo pain
- Non-organic or functional abdominal pain is very common in children over 5 years. This is where no disease process can be found to explain the pain.
- Less severe than in e.g. appendicitis
- DDx: chronic functional pain, IBS, Functional dyspepsia, abdominal migraine
What is intussusception and what sex + age is it most common in?
The bowel invaginates/telescopes in on itself
- male + 3month-2 years
Presentation of intussusception
- colicky abdo pain, vomiting (may be bile stained), constipation (bowel obstr.)
- sausage shaped mass in abdomen
- redcurrant jelly stool
Dx of intussusception
Ultrasound or contrast enema
Mx of intussusception
- enema (contrast, water or air) to pump out invagination
- surgical reduction
- if gangrenous or perforated bowel then resection
Complications of intussusception
obstruction, gangrenous bowel, perforation, sepsis/shock
What is malrotation and volvulus?
- Malrotation - failure of the bowel to assume its normal place in the abdomen during intrauterine development.
- Volvulus - complication of malrotation where the bowel twists around itself causing a blockage so contents cant pass through. Can also cut off blood supply.
Px of malrotation and volvulus?
- Malrotation can be asym. if no twisting.
- volvulus: bilious vomiting, abdominal pain, constipation.
- usually presents within first 24 hours of life but can present at any age
Mx and Tx of malrotation with volvulus
- urgent upper GI contrast study
- surgical correction
Why can malrotation be life threatening
complete volvulus with compromised blood supply can lead to intestinal ischemia, mucosal necrosis and sepsis..
What is an inguinal hernia
An inguinal hernia comprises a protrusion of abdominal contents through the fascia of the abdominal wall, through the internal inguinal ring.
Inguinal hernia presentation
- usually male
- bulge in groin area
- swelling in scrotum
- pain. May appear with straining/lifting.
What is a strangulated inguinal hernia
- contents of hernia (e.g. part of intestines) become twisted, compromising the blood supply. Can cause infarction and bowel obstruction.
Mx of inguinal hernia
surgery
What is Meckel diverticulum and how treat
- malformation of the distal ileum. Usually asymptomatic, but can bleed, become inflamed, rupture or cause a volvulus or intussusception.
- Tx = surgical resection
How is IBS diagnosed and what are the features?
- symptom-based diagnostics without presence of an organic cause.
- [A]bdominal pain (+2of)
- [B]loating
- [C]hange of bowel habit, form, frequency
- [D]iarhoea or constipation intermittent.
Causes of gastroenteritis in children
- Mostly viral: rotavirus, noravirus, adenovirus (more subacute).
- Bacterial: (suggestive by blood in stools). Camplyobacter, Shigella, Salmonella.
Cholera +E coli associated with rapidly dehydrating diarrhea.
Presentation of gastroenteritis
- loose or watery stools and/or vomiting
- febrile
- close contacts, travel, contamination
- blood -> usually camply or e.coli
- assess for dehydration or shock
Signs of dehydration
- weight loss most accurate
- deterioating condition
- altered responsiveness (lethargic, irritable)
- sunken eyes, dry mucous membranes, reduced skin turgor
- tachypnoea, tachycardia
Signs of shock
- deteriorating, decreased consciousness
- pale or mottled skin
- grossly sunken eyes, reduced skin turgor
- tachycardia, tachypnoea, weak pulses, prolonged cap refill, hypotension
Fluid management of dehydration in gastroenteritis
- no dehy: continue breast feed or milk feed, encourage fluid intake, consider ORS
- dehy: ORS/fluid replacement. Consider IV therapy.
If hypernatremic dehydration - use ORS IV slowly reducing plasma sodium. - shock: IV therapy (NaCl)
In hypernatremic dehydration patient why not reduce ORS with low sodium straight away
- want to slowly wean or will lead to shift of water into cerebral cells and may result in seizures and cerebral oedema.
Mnemonics to differentiate Crohns from UC
- (crows NESTS) No blood or mucus, Entire GI tract, Skip lesions (endoscopy), Transmural inflammation, Smoking rf
- (U-C-CLOSEUP) Continuous inflammation, Limited to colon and rectum, Only superficial mucosa, Smoking is protective, Excrete blood and mucus, Use aminosalicylates, PSC
Classic presentation of IBD
- diarrhoea, abdo pain, weight loss, anaemia, fever during flare ups
- blood in stools (more common in UC as may have inflammation around rectum)
Extra-intestinal manifestations of IBD
Crohns: oral lesion, erythema nodosum, clubbing, arthritis, eye problems
UC: erythema nodosum
Ix for IBD
- raised CRP (active inflamm.)
- faecal calprotectin positive
- endoscopy w/biopsy = gold standard
Mx of IBD
- Crohns: inducing remission - prednisolone or hydrocortison (1st line = steroid.) Maintaining remission - azathioprine (1), methotrexate
- UC: aminosalicylate [mesalazine] (1), prednisolone (2). Maintaining - aminosalicylate
- Surgery -> treat strictures and fistulas (2dary to crohns), remove colon and rectum (UC)
What is Coeliac disease
- AI condition, exposure to gluten causes autoantibodies to be produced that target epithelial cells of intestine, resulting of atrophy of intestinal villi in jejnum.
Px of Coeliac disease
- May be asym.
- failure to thrive in young children
- diarrhoea
- fatigue
- mouth ulcers
- anaemia secondary to iron, B12, folate deficiency
- Dermatitis herpetiformis -> itchy blistering skin rash on abdomen
- rarely - neurological symptoms
Ix of Coeliac disease
- anti-TTG
- duodenal biopsy
What is the pathophysiology behind Hirschsprungs
- congenital condition where nerve cells of myenteric plexus absent in distal bowel and rectum.
- > absence of parasympathetic ganglion cells
- myenteric plexus responsible for stimulating peristalsis
Px of Hirschsprungs
- delay in passing meconium (24hrs+)
- chronic constipation since birth
- abdo pain and distension
- vomiting
- poor weight gain and failure to thrive
What is hirschsprung associated enterocolitis and what can it lead to
HAEC - inflammation + obstruction of intestine.
- Hirschsprung Px + sepsis, toxic megacolon, perforation of bowel
Mx of Hirschsprung
- Rectal biopsy - absence of ganglionic cells
- fluid resus and surgicla removal of aganglionic section of bowel
- fluid resus, IV Abx in HAEC
What is biliary atresia
- Congenital condition where section of bile duct is narrowed or absent.
= Cholestasis
Px of biliary atresia
- significant jaundice, persistant more than 14/21 days
Ix of biliary atresia and Mx
- High proportion of conjugated bilirubin. Persisting for 14/21+
- Surgery - Kasai portoenterostomy -> clears jaundice and prolongs survival. Patients require liver transplant to resolve.
Px of constipation + Ix
- hard stools
- difficult to pass, straining
- abdo pain
- faecal impaction causing overflow soiling
- Ix = mass palpable in abdomen
How does desensitisation of rectum cause faecal impaction, in constipation
- Patients ignore sensation of full rectum and lose sensation of needing to open bowels.
- Retain faeces which causes faecal impaction. Can cause overflow soiling
- Over time rectum stretches as fills with more faeces -> leads to further desensitisation of rectum.
Mx of constipation
- high fibre diet + good hydration
- laxatives -> movicol
- faecal impaction -> disimpaction with high dose of macrogol laxative (movicol). Unsucc: Stimulant laxative -> Osmotic laxative
Red flags of constipation due to underlying disease
- Not passing meconium within 24 hrs (CF or Hirschsprung)
- Neurol. signs (Cerebral palsy or spinal lesion)
- Vomiting (Hirschsprung or intestinal obstruction)
- Abnormal lower back (spina bifida)
- Failure to thrive (coeliac disease)
What is Cows milk protein allergy
- hypersensitivity to protein in cows milk
- May be IgE mediated (rapid reaction) or non-IgE mediated (slower reaction)
- (different to lactose intolerance - lactose is a sugar not a protein and cows milk intolerance)
Px of Cow’s milk protein allergy
- usually presents before 1 year of age. May be when weaned off breast milk to cows milk
- GI symptoms:
bloating + wind, abdo pain, diarrhoea, vomiting - General allergic symptoms (rash, swelling, wheeze, sneezing, eczema)
- anaphylaxis in severe cases
