Peads - Acute Abdominal Pain Flashcards
How common is haematemesis in children?
Uncommon
(often due to Mallory-Wiss tear but need to consider other causes)
What questions are important regarding vomiting & stool?
Vomit:
- Frequency, volume, triggers, timeline
- Blood?
- Haematemesis
- Bile?
- Bilious vomiting = always abnormal
Stool:
- Frequency, consistency / form, timeline, Bristol stool chart
- Blood?
- Stool - fresh on wiping (?peri-anal pathology), on outside of hard stool (?constipation), mixed in with soft stool (?infection - likely bacterial blood in stool)
- Mucus - possible infection
What are functional GI disorders?
Functional GI disorders are common disorders characterised by persistent & recurring GI symptoms due to ‘abnormal functioning’ of the GI tract
(I.e. NOT due to structural or biochemical abnormalities - thus scan and blood tests often appear normal)
Examples:
- Irritable Bowel Syndrome (IBS)
- Functional dyspepsia
- Functional abdominal pain
- Functional constipation or diarrhoea
In a paediatric GI case what ‘red flag’ features can you name that would prompt further investigation?
History:
- Age < 5yrs
- Systemic symptoms: weight loss, fever, dysphagia, vomiting (?blood, bilious)
- Nocturnal symptoms - that wake child from sleep
- Persistent RU or RL abdo pain
- Dysuria / haematuria / flank pain
- Chronic NSAID use
- FHx of IBD / coeliac / peptic ulcer disease
Examination:
- Growth deceleration
- Delayed puberty
- Jaundice or Pallor
- Rebound / guarding / organomegaly
- Perianal disease
- Blood in stool
Investigations:
- ↑ WCC
- ↑ inflammatory markers
- anaemia or hypoalbuminaemia
Abdominal tenderness / pain can be difficult to evaluate when examining a child, what other observation can provide information as to whether the child is in pain?
Behaviour
- Walking normally / normal play / climb onto bed without discomfort = likely not in serious pain
What are some common causes of malaena in children?
- Infection - e.g. bacterial diarrhoea ( e.g. campylobacter, salmonella)
- IBD - Crohn’s or UC
- Tearing of anal vein
- Polyp
- Intussusception - child will be acutely unwell
What investigation can be done on stool if suspecting IBD?
Faecal Calprotectin Test
- Faecal calprotectin ↑↑ (up to 10 times) in IBD
- Not specific for IBD!! - can be ↑ due to polyps or infection
- Faecal calprotectin = normal in IBS
How does the Faecal Calprotectin Test work?
- Calprotectin = complex of proteins, which in the presence of Ca2+ can sequester metals; iron, manganese and zinc –> this gives antimicrobial properties
- Calprotectin comprises up to 60% of soluble content of cytosol of neutrophils –> which secrete it during inflammation
- IBD –> causes migration of neutrophils into intestinal mucosa –> which secrete calprotectin, which moves into the intestinal lumen = faecal calprotectin –> thus faecal calprotectin is ↑ inflammatory bowel diseases (UC and Crohn’s can have 10x ↑ in faecal calprotectin)
What features are common to both UC and Crohn’s, including ‘extra-intestinal’ symptoms?
- Abdominal pain
- Diarrhoea
- Fever
- Weight loss (more so in Crohn’s)
- Arthralgia / arthritis in large joints (most common extra-instestinal features of both UC and Crohn’s)
- Ulcers in mouth and vagina - (more common in Crohn’s)
- Anterior uveitis - inflammation of iris (pain, photophobia, redness, irregular pupil)
- Skin:
- Erythema Nodosum - painful itchy raised round lumps (1-5cm), commonly on legs (more common in UC)
- Pyoderma gangrenosum - dead black pus necrotic tissue, commonly on legs or around stoma
- Primary sclerosing cholangitis (more common in UC)
What are the key features of Ulcerative Colitis?
Define:
- UC is a relapsing-remitting disease characterised by;
- Colon inflammation (lead-pipe appearance on barium enema)
- Rectal bleeding
- Ulcers interspersed with preserved mucosa –> producing pseudo-polyps
Signs/Symptoms:
- Bloody diarrhoea
- Mucus in stool
- Tenesmus - feeling of incomplete defecation
- Feacal urgency
- Abdominal pain (particularly LLQ)
- Extra-intestinal features
Physiology of Inflammation:
- Inflammation is worse/starts distally in the rectum and can progress proximally BUT rarely passes ileocecal valve
- No inflammation beyond submucosa (confined to mucosa + submucosa)
- Neutrophils migrate into glandular lumens forming ‘crypt abscesses’
-
40-50% Proctitis = inflammation of anus/rectum (only first 6 inches of rectum)
- Proctosigmoiditis = inflammation of rectum + sigmoid colon
- 30-40% Left-sided colitis = Inflammation can spread in proximal direction i.e. from rectum/sigmoid backwards through descending colon
- 20% extensive colitis = Inflammation can spread further proximally to involve transverse colon
- Pancolitis = inflammation of entire colon
Prognosis:
- NO ↓ in mortality, 10-30% need colectomy (within 10yrs post onset)
Flares of Ulcerative Colitis can be classified as; Mild, moderate and severe - what are the features of each?
-
Mild:
- < 4 stools / day (with/without blood)
- No systemic disturbance
- Normal ESR + CRP
-
Moderate:
- 4-6 stools / day (with/without blood)
- Minimal systemic disturbance
-
Severe:
- > 6 stools / day - contains blood
- Evidence of systemic disturbances e.g.
- Fever
- ↑ HR (tachy)
- ↑ ESR
- Abdo pain, distension or reduced bowel sounds
- Anaemia
- Hypoalbuminaemia
What tests might you want to do in a patient with UC?
Beside:
- Obs - ↑ temp, ↑ HR, ↑ RR in severe flare of UC
- Abdominal exam - LLQ pain, clubbing, erythema nodosum, pyoderma gangrenosum, iritis
- PR exam - may show blood on glove
- Stool sample - ↑ WBCs suggestive of infective cause
Bloods: - in flare
- FBC:
- ↑ WCC
- ↑ platelets
- ↓ Hb (iron-deficient anaemia)
- ↑ ESR
- ↑ CRP
- pANCA - may be positive in UC (usually negative in Crohn’s)
Other tests:
- Flexible sigmoidoscopy - often shows inflammation, ulceration and bleeding mucosa (is rare rectum/sigmoid are clear in UC)
- AXR - may show air in colon + colonic dilation (often only needed in acute emergency presentations)
-
Barium Enema: - in UC:
- Loss of haustrations
- Superficial ulceration
- Long standing UC: shortened + narrow colon ‘leadpipe’
- Colonoscopy:
- Should not be used during actue attacks of IBD
- Can be used during remission to assess; extent of IBD, perform biopsies to rule out malignancy
What are 4 potential complications associated with UC?
- Bleeding
- Perforation
- Toxic megacolon
- Colorectal cancer
What drugs are used to induce remission of UC and which are used for maintiaining remission?
Induce Remission:
- Acute mild:
- 1st line = Topical (suppository or enema) mesalazine
- 2nd line = Topical (suppository or enema) mesalazine + oral prednisolone
- Acute moderate:
- Topical (suppository or enema) mesalazine (aminosalicylate anti-inflammatory) + oral prednisolone
- Acute Severe:
- 1st line = IV steroids e.g. hydrocortisone
- 2nd line = Ciclosporin (immunosuppresant) or Infliximab (monoclonal antibody - not advised due to lack of evidence but is more effective in Crohn’s)
- 3rd line = surgery (colectomy)
Maintaining Remission:
- Oral aminosalicylates e.g. Mesalazine
- Thiopurines e.g. azathipurine or mercatopurine (immunosuppresants)
What are the key features of Crohn’s Disease?
Define:
- Relapsing-remitting disease
- Can affect any part of GI tract (mouth-anus) often present as ‘skip lesions’ = areas of pathology with gaps of healthy GI tract in-between
- Often involves all layers of bowel + pattern of inflammation gives cobblestone appearances
- Rectum is rarely affected BUT anus often is (fistulae + perianal abscesses)
Signs/symptoms:
-
Diarrhoea (usually non-bloody)
- Can cause constipation if blockage forms e.g. stricture
- Weight loss - crohn’s often affects small intestine (failure to thrive in children)
- Abdominal pain (can mimic appendicitis i.e. umbilical –> LRQ)
- Right iliac fossa mass - 70% of Crohn’s affects the terminal ileum - can produce an abscess
- Fistulae + Abscesses - results from full thickness ulceration of GI tract
- Perianal disease - e.g. skin tags or ulcers
- Non-necrotising granulomas
- Gallstones + renal stones - more common in Crohn’s secondary to reduced bile acid reabsorption (Crohn’s affects small intestine)
- Fat wrapping - mesentery becomes thickened and wraps around bowel to anti-mesenteric border
- Extra-intestinal symptoms
Physiology of Inflammation:
- 40% ileocecal area (ileum + cecum)
- 30-40% small intestine - inflammation appears in segments (skip lesions)
- 20% Crohn’s Colitis = skip lesions in colon (large intestine)
- <10% Perianal inflammation
Prognosis:
- Slight ↓ mortality
- ~50% need surgery (within 10yrs post diagnosis)
What are the 4 main complications of Crohn’s Disease?
- Stricture - can cause obstruction, presents as ‘acute abdomen’ can mimic appendicitis
- Fistulas = abnormal connnection between 2 organs e.g. bladder-bowel
- Adhesions
- GI cancer - commonly adenocarcinomas of terminal ilieum
What test might you do for a patient with Crohn’s Disease?
Bedside:
- Abdominal exam - acute abdomen, LRQ pain/mass, clubbing, erythema nodosum, pyoderma gangrenosum, mouth ulcers, iritis
- PR exam - may have blood on glove, identify perianal abscess / skin tags
- Stool samples - to exclude infective diarrhoea (↑ WBCs)
Bloods:
- FBC:
- ↑ WCC (if disease active)
- ↓ Hb (anaemia)
- Serum Iron + B12 if anaemic on FBC - ↓ B12 anaemia
- ↑ CRP
- ↑ ESR
- LFTs - may be deranged if gallstones are present
- U+Es - may be deranged if renalstones are present
Other tests:
- Faecal calprotectin test
- CT - can show fistuals, fistulas and bowel wall changes
- Barium swallow - shows; strictures, mucosal changes and fistulas and picture of skip lesions
How is smoking advice potentially different in UC vs Crohn’s?
- Potentially don’t stop smoking in UC –> protective in UC, stopping smoking ↑ risk of relapse
- Stop smoking in Crohn’s –> it can be enough to maintain remission
How is Crohn’s Disease managed?
Crohn’s is NOT treated if asymptomatic (unlike UC)!!
Lifestyle:
- Low residue diet (↓ high-fibre foods e.g. nuts, seeds, fruit and veg) is advised in those with stricture
Pharmacological:
- Acute flares:
- 1st line = Glucocorticoids
- 2nd line = aminosalicylates (5-ASA drugs) e.g. Mesalazine
- Adjunct: Thiopurines e.g. azathipurine or mercatopurine (immunosuppresants) or Methotrexate
- Last line prior to surgery: Infliximab (monoclonal antibody)
- Surgery
- Maintaining remission:
- Stop smoking!!
- Azathipurine or mercatopurine
If you were to draw the colon and small intestine to demonstrate affected areas in UC vs Crohn’s how would each look?

Clostridium Difficle is an organism which is part of normal gut flora.
Abx can make it more predominate by killing competing organisms. This can present with what symptoms?
And what complications?
Symptoms of C.Diff infection:
- Diarrhoea
- Fever
- Nausea
- Abdominal pain
- ↑ WCC
Complications:
- C.Diff colitis
-
Toxic megacolon
- Acute form of colonic distension/dilation, which is often accompanied by paralysis of peristalsis, which can lead to accumulation of faeces in the immotile segment. Also characterised by
- Very distended colon
- Abdo pain
- Fever
- Bloating
- Colon perforation
- Sepsis
How do you manage a C.Diff patient?
- Discontinue offending Abx
- Oral vancomycin or fidaxomicin or metronidazole
- Isolate pt in side-room
- Gown + glove interaction with patient
- Fluid support if dehydrated due to diarrhoea
How do Aminosalicylate (5-ASA) drugs work?
5-aminosalicylic acid acts as a local anti-inflammatory agent
(mechanism not fully understood - may inhibit prostaglandin synthesis)
More effective in UC and less effective in Crohn’s management!
What is Azathioprine?
It is an immunosuppresive medication
Commonly used in:
- Crohn’s - for maintaining remission or as adjunct to steroids or mesalazine in inducing remission
- RA
- SLE
- Myasthenia Gravis

