Constipation Paeds

Question 1

A 11 y/o with a Hx of recurrent abdominal pain presents with constipation and periumbilical pain. She says she feels bloated and never really feels like she empties her bowels but her symptoms improve after she has defecated. O/E she is normal. What is he most likely Dx and what is your management?

1. Hirschsprung’s
2. ARM
3. Spina Bifida
4. Tethered Cord
5. Functional Constipation
6. Cow’s milk allergy
7. Congenital Hypothyroidism
8. Coeliac’s disease
9. IBS
10. Perianal Crohn’s
11. CF

Answer 1

IBS

Bloating, tenesmus, periumbilical pain and constipation are common signs of IBS although patients can also experience diarrhoea. Her Hx of recurrent abdominal pain is also suggestive.

IBS is however a Dx of exclusion and thus the following should be performed.

• FBC for inflammatory processes
• CRP and Faecal calprotectin as these are raised in IBD
• Stool sample for MC&S
• Serology for anti-tTG and endomysial Abs
• Sigmoidoscopy and ODG for biopsy to exclude Coeliac’s and IBD

Tx

• There is no specific Tx for IBS but some foods may trigger flares (Caffeine, Lactose, Fructose) with high fibre and hydration helping most patients
• Laxatives or anti-diarrhoeals may also be given depending on severity of symptoms

Question 2

What are the red flag symptoms of constipation?

Answer 2

• Failure to pass meconium within 24hrs and distension (Hirschsprung’s)
• Anal or Genital abnormalities (ARM)
• Altered growth/failure to thrive (Coeliac’s/Hypothyroidism)
• Abnormal skin over lumbosacral region (Spina Bifida)
• Perianal fistula (Crohn’s)

Question 3

A 3 day old baby has failed to pass Meconium with explosive diarrhoea and bile-stained vomiting. O/E they are feverish with abdominal distension but a normal anus. What is the most likely Dx and what is your management?

1. Hirschsprung’s
2. ARM
3. Spina Bifida
4. Tethered Cord
5. Functional Constipation
6. Cow’s milk allergy
7. Congenital Hypothyroidism
8. Coeliac’s disease
9. IBS
10. Perianal Crohn’s
11. CF

Answer 3

1. Hirschsprung’s

The failure to pass meconium with signs of obstruction (bile-stained vomiting and explosive diarrhoea) and a normal anus suggests Hirschsprung’s. The presence of fever also indicates that this baby has Enterocolitis.

Hirschsprung’s is caused by an absence of ganglion cells in the myenteric and submucosal plexi resulting in an irregularly contracted segment of bowel beginning distally. 75% are rectosigmoid with 10% covering the entire colon.

Ix

• FBC, U&E and CRP (Infection and Hydration)
• ABG/VBG for status
• Stool culture for MC&S
• AXR with contrast enema for obstruction
• Rectal Biopsy to confirm (Ganglionic Hypertrophy >40 microns with increase anticholinesterase activity)

Tx

• Colon irrigation + Metronidazole (for enterocolitis)
• Decompression with colostomy or ileostomy may be required if irrigation fails
• Definitive surgery to remove aganglionic segment with pull-through

Prognosis is good if caught early but worsens if enterocolitis or short-bowel syndrome secondary to large amount of bowel removal

Question 4

A new-born has yet to pass meconium. Upon new-born examination, the anus is absent and the external genitalia look abnormal. Urinalysis shows faecaluria. What is the most likely Dx and what is your management?

1. Hirschsprung’s
2. ARM
3. Spina Bifida
4. Tethered Cord
5. Functional Constipation
6. Cow’s milk allergy
7. Congenital Hypothyroidism
8. Coeliac’s disease
9. IBS
10. Perianal Crohn’s
11. CF

Answer 4

2. ARM

ARM encompasses a wide spectrum of conditions. Low level ARMs can involve a misplaced anus (anocutaneous fistula) or anal stenosis with intermediate level cases involving anal agenesis, rectal atresia and rectourethral/vaginal/vestibular fistula. The most severe (high) malformations involve anorectal atreasia, rectovesical fistula and cloacal anomalies(urethra, vagina and rectum all linked)

This appears to be a intermediate malformation with a rectourethral fistula and anal agenesis.

Ix

• New-born, Neurological, abdominal and cardiac examinations due to possibility of VACTERL malformations (Vertebral 25-30%, Anorectal, Cardiac 30-35%, Tracheoesophageal, Renal/Genital 40-45% and Limb)
• FBC and CRP for infection
• U&E and Urinalysis for Infection/Faeces
• USS of genitourinary tract, anus/rectum and spine
• Echocardiogram
• MRI to guide surgical management

Tx

• NBM and manage hydration/nutrition parenterally in severe malformation
• MDT approach and counselling for parents
• Prophylactic Amox/Trimeth/Sulfamethoxazole if fistula to urinary tract suspected
• Surgical intervention (Single stage or multi-stage. PSARP preferred approach but colostomy may be the only option in severe cases or if surgery is contraindicated due to comorbidities)

Prognosis varies depending on the degree of malformation and presence of comorbidities but worsens if surgical complications. ~80% have normal bowel function with intermediate malformations falling to only 15% with rectovesicular malformation

Question 5

A 4 y/o presents with infrequent bowel movements. His mothers says he doesn’t like using the toilet and has occasionally soiled his pants. The chill is otherwise well, has a good diet but doesn’t drink as regularly as the mum would like. The child is growing well, has a soft abdomen but a hard lump can be felt centrally in the pelvis. You do not perform a DRE but inspect the anus, it is normal. The childs lower limb function and skin over the lumbosacral spine are normal also. What is the most likely Dx and what is your management?

1. Hirschsprung’s
2. ARM
3. Spina Bifida
4. Tethered Cord
5. Functional Constipation
6. Cow’s milk allergy
7. Congenital Hypothyroidism
8. Coeliac’s disease
9. IBS
10. Perianal Crohn’s
11. CF

Answer 5

5. Functional/Idiopathic Constipation

This is most commonly caused by poor diet/dehydration resulting in hard faeces that is painful to pass. This results in witholding that perpetuates the cycle as the faeces are larger and harder when they finally are passed. As the rectum dilates, the child looses sensation so may soil themselves after them have previously learnt to control bowel movements. The child is often normally otherwise well.

Constipation often occurs following a precipitating factor which may be infection, change n diet, potty training or medication.

Other causes may be psychosomatic due to anxiety or fear that increases the tone of the internal anal sphincter which is not under voluntary control.

90-95% of constipation is idiopathic with a normal examination and a characteristic Hx but there are signs of pathology/abuse which should be checked during the Hx and exam. Amber signs = failure to thrive/grow, suspicion of child welfare issues and signs of perinal infection. Red flags = Anal fissure, perianal abscesses (Crohn’s), failure to pass meconium (Hirschsprung’s), signs of spina bifida (lower limb neuro deficits and abnormal skin over lower back) and vomiting with abdominal distension sugesting obstruction

Ix
- Full Hx exploring Onset, precipitating factors and comorbidities
- Neuro and Abdominal exams
If amber signs
- Growth retardation = test for Coeliac’s/Thyroid function
- Child welfare = follow guidelines on child abuse and neglect (raise concerns with seniors with potential for social services involvement)
Psych/Behavioural assessment if there are signs of psychosomatic/behvaiour disturbances that are causing the functional constipation
Assess all children for faecal impaction via Hx
 Only competence specialist should perform a DRE

Tx
Impacted?
1st line = Movicol (Polyethylene glycol)
Adjunct with stimulant laxative (Senna) if not improoovement within 2 weeks)
2nd line = Senna + osmotic laxative (Lactulose) if Movicol isn’t tolerated
- Warn parents this may initially worsens symptoms but is required

Maintenance if no impaction or once impaction is cleared
- Same as above but continue and taper dose once normal bowel habits resumed (This may take some time with some children on laxatives for a couple of years)

If fissure

• Ensure soft stools (diet and hydration) and consider Tx for constipation as above
• Advise against withholding and offer methods to relieve pain (Paracetamol/Ibuprofen or shallow warm baths)
• Emphasise importance of good hygiene
• If not improvement within two weeks, come back

Behavioural interventions for all

• Dietary education, in particular fibre and hydration
• Scheduled toileting, particularly after meals to utilise gastrocolic reflex
• Reward good bowel habits

Provide everyone with follow-up referrals to check progress for ALL

• Refer urgently to specialist if <1yr no response within 4 weeks to optimum Tx
• Refer to specialist if >1yr and no response within 3 months

Question 6

A 2y/o is brought in by their mum as they are always cold, don’t eat much and has constipation. The mother says she had prolonged jaundice as a baby but the Guthrie test revealed a normal TSH. You conduct a developmental Hx and they are yet walk, cannot join words together and still requires nappies during the day. What is your most likely Dx?

1. Hirschsprung’s
2. ARM
3. Spina Bifida
4. Tethered Cord
5. Functional Constipation
6. Cow’s milk allergy
7. Congenital Hypothyroidism
8. Coeliac’s disease
9. IBS
10. Perianal Crohn’s
11. CF

Answer 6

7. Congenital Hypothyroidism

Congenital Hypothyroidism presents in a similar fashion to adults but prolonged jaundice and developmental delay are additional features. The normal Guthrie test may mislead people but this may be a sign of central hypothyroidism due to pituitary dysfunction (low TSH). This is rare but shouldn’t be forgotten. The most common cause is Athyrosis/Maldescent with dyshormonogenesis more common among children of consanguineous parents. Iodine deficiency is a common cause in under-developed countries.

Ix

• Newborn Hx, Developmental Hx and Thyroid exam
• FBC
• TSH, T3 and T4
• Pituitary function test

Tx

• Lifelong Levothyroxine (This should be given within 2-3 weeks of birth to prevent developmental delay)
• Key points to explain condition, explain importance of medication and that if the medication is taken the child is expected to develope normally.

Question 7

A 11 y/o with growth retardation presents with Fever, constipation and crampy abdominal pains. There is no blood or mucous upon defaecation. This is her third episode this year. O/E her abdomen is tender and you she perianal fistula. What is he most likely Dx and what is your management?

1. Hirschsprung’s
2. ARM
3. Spina Bifida
4. Tethered Cord
5. Functional Constipation
6. Cow’s milk allergy
7. Congenital Hypothyroidism
8. Coeliac’s disease
9. IBS
10. Perianal Crohn’s
11. CF

Answer 7

10. Perianal Crohn’s

Crohn’s is less common than UC in children but the crampy abdominal pain, presence of perianal fistula and absence of blood/mucus suggests Crohn’s. It is the pain from the fistula that is the likely cause of the constipation which, in combination with the growth retardation, refractroy nature and Fever, suggests quiet advanced disease that has flared.

Ix

• FBC, CRP for infection
• Haematinics for nutritional status
• U&E for hydration
• Stool sample for Calprotectin and MC&S
• Biopsy showing patchy ulceration and non-caseating epitheloid granulomata

Tx

• Induce with IV Hydrocortisone or Oral Prednisolone as this is severe (Budesonide and ASA not suitable in this case)
• Add Azathioprine or 6-Mercaptopurine as >2 flares requiring steroids <12 months (or unable to taper steroids) Check TMPT activity first!!
• Biologics if the above fails
• You can attempt to induce remission with parenteral whole protein modular feeds but given the severe nature of this case and refractory nature this is unlikely to work
• Once remission is induced, maintenance with Azathiorpine or 6-mercaptopurine (Methotrexate if TMPT activity is low)

This patient is not suitable for surgical induction as it is not limited to the distal ileum despite them having growth retardation and refractory disease.

Question 8

What are the key points about constipation in children>

Answer 8

How frequent are bowel movements?
o 4x daily during first week
o 2x daily during first year
o 1x daily thereafter

Those who are breastfed may not have a bowel movements for a few days and be perfectly healthy

General points
o Constipation comes on acutely and typically resolves spontaneously
o Examination is often normal with a well child
o DRE should not be performed
o In long-standing constipation, the rectal dilates with the loss of the sensation to defaecate -> involuntary soiling
 This can take a long time to return to normal after constipation resolves

Question 9

A 12 month old presents as they are failing to thrive and have dropped down on the growth chart percentiles. Their mother says she is constipated and is generally irritable. When asked, the mother said she has recently started to give her child solids such as biscuits. What is the most likely Dx and what is your management?

1. Hirschsprung’s
2. ARM
3. Spina Bifida
4. Tethered Cord
5. Functional Constipation
6. Cow’s milk allergy
7. Congenital Hypothyroidism
8. Coeliac’s disease
9. IBS
10. Perianal Crohn’s
11. CF

Answer 9

8. Coeliac’s

It is less common to present this early but the recent change in diet to include gluten, the constipation and irritability are suggestive of Coeliac’s

Ix

• FBC and CRP for inflammatory processes
• Haematinics for malnutrition
• Dx confirmed by serology (anti-tTG and EMA) and Biopsy obtained by ODG (villous atrophy with >25:100 lymphocyte to epithelial ratio and crypt hyperplasia)

Tx
- Gluten free diet

PACES Counselling
o Explain the diagnosis (caused by an inability to digest gluten (present in barley, rye and wheat))
o Reassure that it is a common condition (1 in 100) and the treatment is fairly straight forward (gluten-free diet)
o Explain that they will be put in touch with a dietician
o Explain the importance of keeping to a strict gluten-free diet (complications include malnutrition and cancer)
o Explain that follow-up is usually necessary every 6-12 months
o Advise regular measurements of height and weight on centile charts
o Support: Coeliac UK

Question 10

A neonate has failed to pass meconium and is vomiting. They also have prolonged jaundice. O/E they have a distended abdomen with a sausage shaped mass. What is the most likley Dx and what is your management?

1. Hirschsprung’s
2. ARM
3. Spina Bifida
4. Tethered Cord
5. Functional Constipation
6. Cow’s milk allergy
7. Congenital Hypothyroidism
8. Coeliac’s disease
9. IBS
10. Perianal Crohn’s
11. CF

Answer 10

11. CF

CF is due to being homozygous for mutations in the CFTR gene that encodes a Cl- channel. Defective Cl- transport leads to thickened secretions which block lumens.

In neonates this presents with meconium ileus (failure to pass meconium with sausage mass and vomiting due to obstruction). They may also have prolonged jaundice.

Older children present with recurrent infections of the chest, GORD, malabsorption/developmental delay and rectal proplaspe due to increased stool bulk.

Advanced cases present with pancreatic insufficiency, Cirrhosis/ portal HTN, bronchiectasis, pneumothoracies and haemoptysis.

Diagnosis is normally made via molecular Dx of the mutated gene and raised chloride sweat test >60mmol/L following a raised immunoreactive trypsinogen on the heel-prick test.

Tx

• MDT approach involving: Paediatricians, nurses, Psychologists, Physios, Dieticians and social workers
• Respiratory (Physio techniques/education for airway clearance + Mucoactive agents and prophylactic Flucloxacillin if lung disease)
• Diet = High calorie with enteric coated enzymes and fat soluble vitamins
• Regular psych reviews and support
• Laxatives if DIOS (distal ileum obstructive syndrome)
• Ursodeoxycholic acid to delay cirrhosis by improving bile flow
• Diabetes managemnt if present

PACES Counselling
o Explain the diagnosis (lifelong condition characterised by thick secretions)
o Explain that that management requires an MDT approach
o Explain that they will be referred to a specialist cystic fibrosis centre to discuss the ongoing management
o Offer to outline the aspects of management:
• Pulmonary – physiotherapy, mucolytics
• Infection – prophylactic antibiotics, monitoring
• Nutrition – enzyme tablets, high-calorie diet, monitor growth
• Psychosocial – provide support for child and carers
o Offer information on genetic counselling if considering having more children
o Support: Cystic Fibrosis Trust