MANAGEMENT OF CONSTIPATION IN CHILDREN


Afzal NA
Clinical Research Fellow & Honorary Specialist Registrar in Paediatric Gastroenterology
University College of London, Royal Free & Chelsae and Westminister Hospitals


Thomson MA
Consultant Paediatric Gastroenterologist and Honorary Senior Lecturer
Royal Free Hospital and University College of London



"MANAGEMENT OF CONSTIPATION IN CHILDREN"
Normal bowel patterns are very variable in children of all age groups. Weaver and Steiner have shown that 85% of 1 to 4 year olds pass stools once or twice a day and 96% do so three times per day to once every other day.1 When there is delay in defaecation with difficulty or distress, the child is said to suffer from constipation.1 Constipation has also been defined as passing less than 3 stools per week. A child is also said to be suffering from constipation if he or she has painful bowel movements (due to hard or large stools) and stool retention in spite of passing stools more than 3 times per week.2
Constipation is a common problem. It is said to account for 3% of all visits to a paediatric practice and 25% to a paediatric gastroenterology clinic.3,4 The percentage of children suffering from constipation is said to vary from 0.3 to 8% according to different studies.3 The male female ratio is 1: 1 in young constipated children.3 There is a male pre-dominance in children > 5 years old with a reported ratio of 3-6:1.3 At follow up, twice as many boys than girls had soiling and 1.8 times girls than boys were still constipated despite receiving laxatives.3

Presentation
97% of the children presenting with constipation are said to show stool-withholding manoeuvres e.g. crossing their legs or sitting up on their heels. Painful bowel movements have been shown to be present in 77-86% often associated with screaming and only 58% with infrequent bowel movements.3 A rectal/ abdominal stool mass is palpable on deep abdominal palpation in 66-77%.3,5 Hence, if the diagnosis of constipation were just based on infrequent bowel habit, the diagnosis would be missed in almost half of the children with constipation. Recurring UTI may be present in 3.7-30%.3,6

Management
The following aspects should be covered in management of constipation in children:
1. Aetiology
2. Education and Behavioural therapy
3. Diet
4. Laxatives
A. Initial Evacuation
B. Maintenance treatment
C. Monitoring
5. Special Cases

1. Aetiology
Organic causes are rare and account for < 10% of constipation in children even in secondary or tertiary referral centres.2,3 Hence the number of children seen in a general practice with organic constipation is even lower.
Symptoms and signs in Table 1 (see appendix) should prompt a practitioner in the community to refer the child to a paediatrician with an interest in gastroenterology/ paediatric gastroenterological unit.
Idiopathic constipation commonly starts after a specific identifiable trigger. A viral infection may result in decreased intake of liquids. Stools become solid causing the child to strain and passage of hard faeces may result in an anal fissure. Defaecation becomes painful which starts a negative cycle, leading to retention of stools. Other common triggers are unavailability of toilet on holiday/camping, school restrictions, teasing by classmates, and access to a smelly facility or sharing the same toilet with several family members.4
Hirschsprung's disease is commonly considered in any child with chronic constipation. However, it has been shown that if the age at onset of constipation is after the neonatal period, Hirschsprung's is an extremely unlikely diagnosis.7
Cow's milk allergy may be aetiological in up to 40% of chronic constipation.8 Strong history of atopy in the individual/family, low IgA, history of gastro-oesophageal reflux refractory to treatment, blood in stool and recurrent viral infections in early childhood may be suggestive of such a diagnosis.9 The appropriate treatment would be removal of the offending agent from the diet and in children less than 2 years of age, substitution with a casein or whey hydrolysate such as Prejestimil, Nutramigen and Peptijunior rather than soya is recommended (Soya displays upto 50% cross reactivity with cow's milk protein). After two years of age, soya might be needed because of its superior palatability over hydrolysate milks. In such cases, rice based milks supplemented with calcium is also a useful alternative. Such cases could be referred to a paediatrician with interest/ gastroenterologist for diagnosis and management.

2. Education + Behaviour therapy 10
A confirmatory diagnosis with a detailed explanation to the parent is vital for successful future treatment. Abdominal X Ray, if done, may be used to explain the problem. If the child is old enough, he or she should take an active part in the consultation.
Soiling leads to frustration in parents and they often feel that the child is doing it deliberately. Chronic constipation can lead to a mega-rectum (enlarged rectum) with decreased feeling for the presence of stool and hence defaecatory stimulus due to persistent distension. It is vital that parents understand that this is not a deliberate act. Negativity from the parents can worsen the problem.
Some parents stop medication as they find that once the stool becomes loose the discomfort still persists. Lack of compliance due to a whole variety of reasons is common. It is again vital that parents understand the importance of regular maintenance treatment.
Children should not hurry when sitting on the toilet. They should ideally sit on the toilet post-breakfast to allow the gastro-colic reflex to prompt defaecation. Foot support to assist in hip flexion using a children's toilet seat may be helpful. A diary should be kept for record of stool passage and a reward system should be used. This should be reinforced every time the medical practitioner sees the child.4
Abnormal defaecation dynamics have been observed in 25-50% of children with constipation. Biofeedback training has been used. However, when compared with conventional drug treatment of constipation, biofeedback does not show better long-term recovery in children.5 Moreover, this technique is only usable in an older child and is, to some extent, invasive.

3. Diet
29-48% are found to be 'fussy eaters' and 16-47% are described to have a poor appetite. Usually eating improves once the constipation is treated.11
Increased intake of fluids with absorbable and non-absorbable carbohydrate helps to soften the stools. Carbohydrates (especially sorbitol in prune, pear and apple juices) can cause increased frequency and water content of stools.4 A balanced diet with whole grains, fruits and vegetables is recommended. There are no Randomised Controlled Trials (RCTs) to prove that these measures are helpful, though it has been shown that reduced fibre intake is more prevalent among constipated children. Forceful implementation of diet leading to confrontation around meal times should be discouraged.4

4. Laxatives
Laxatives can be divided into four groups based on their mechanism of action.
1. Bulk forming laxatives, which increase faecal mass and stimulate peristalsis (Methyl cellulose, Ispaghula)
2. Stimulant laxatives, (Docusate, Senna, Picosulphate) which increase intestinal motility
3. Faecal softeners (Liquid Paraffin) whose action is mainly to lubricate and soften the stool probably by lining colonic pits and preventing colonic water re-absorption. It is also a mild stimulant.
4. Osmotic laxatives (Magnesium salts, Lactulose, Polyethylene Glycol, Phosphate Enemas), which keep fluids in the bowel by osmosis or by changing the pattern of water distribution in the faeces.

A - Initial Evacuation (See Algorithm)
The stools should be softened before a stimulant is used. Otherwise contraction of bowel against a hard immobile stool may cause severe abdominal cramps and produce no result. Lactulose is usually the first laxative prescribed and a high dose may achieve an evacuation in mild cases with the slight drawback of colonic gas accumulation. If unsuccessful, a dose of sodium picosulphate 6five days later usually achieves evacuation, which may be repeated if necessary. There are no RCTs to support efficacy, though studies of bowel preparation in adults show picosulphate to be more tolerable than ethylene glycol and as effective.13 Sodium picosulphate (for school-aged children) should be used on Friday/Saturday evenings to avoid accidents at school on the following day.
If the above regimen fails we recommend regular paraffin oil 6,14,15, and if needed a dose of sodium picosulphate may be given on the 5th day to achieve complete evacuation.6 In some instances, especially recto-sigmoid faecal impaction, enemas may be needed.6 Hospitalisation may also be needed for refractory cases in order to have NG administration of non-absorbed poly-ethylene glycol (PEG) solution until clear faecal effluent is achieved 13,16or for rectal evacuation under anaesthetic. Recently, Movicol (Polyethylene Glycol sachets) has been used with success, though its use is still unlicensed in children.13 If there is relapse of symptoms, evacuation may need to be repeated.
There are no RCTs to show efficacy of drugs like Senna, bisacodyl etc but they have been used with success.

B - Maintenance treatment (See Algorithm)
An effective approach is to use an osmotic laxative and add a stimulant after a few days, if needed. The commonest osmotic laxative used is lactulose and stimulant is docusate.17 There are no RCTs to show effectiveness of docusate, but we have found it useful in our clinical practice. Senna is effective and may be used where docusate fails, though the trend now in most paediatric centres is to avoid prolonged use due to its side effect profile.3,6,14,17,18,19,20
In severe constipation, paraffin oil and where necessary sodium picosulphate on Friday and Saturday evenings is very effective.6 Paraffin has been shown to be more effective than long-term usage of Senna.14 Lipoid pneumonia and fat-soluble vitamin deficiency has not been found to be a problem,15 the latter is a popular misconception and is based on a single small case series with flawed methods and conclusions from 1935 and this myth has subsequently been dismissed. There have been two cases reported with lipoid pneumonia in the last 20 years in the literature, though we have not come across any in our clinical practice. If needed, pro-kinetics have been shown to be a useful adjunctive treatment. Recently Movicol, though unlicensed, has been used for maintenance treatment in children13 with promising results shown by adult studies.21,22,23 Regular enemas or suppositories are to be strongly discouraged.4
We use "scheriproct - hydrocortisone topical cream" for anal fissures which is better than lignocaine jelly.24 Glyceryl trinitrate (0.2-1%) or isosorbide dinitrate paste have also been used for anal fissures with good success.25 Peri-anal streptococcal infection is rare and, if present, a penicillin is used for treatment.11

C - Monitoring treatment
The key to successful treatment is proper evacuation with appropriate maintenance therapy. The medication doses have to be increased or decreased according to each individual's requirement. It is important that the doses should not fluctuate too often e.g.: using a dose of 5 mls one day and then 30 mls the next day and then going to 15 mls on third day. The dose change should be planned and gradual.
Diarrhoea with laxative treatment does not automatically mean too much dose. It may often be a sign of overflow i.e. inadequate treatment. In such a case the appropriate treatment would be to increase the dosage with probably a repeat evacuation. Judicious use of abdominal X Ray may allow differentiation.6
Follow up should be frequent initially and if possible should be done by the same practitioner otherwise the child/parent/doctor team begins to fragment.
Most parents often ask - 'when to stop the treatment?' Unfortunately there is no single answer. Common practice is to aim for one bowel movement per day on constant dosage. Subsequently after a period of months rather than weeks gradual decrease in dosage of laxatives may be initiated in very small steps. We use an arbitrary figure of 3 months. One needs to be aware that this may be accompanied by re-emergence of symptoms.

5. Special Cases
Management of constipation can be a challenge in children with neuro-developmental problems. In addition these children may have a poor diet low in roughage and fluids. They may have undiagnosed and untreated gastro-oesophageal reflux and gastrointestinal dysmotility. These factors make management difficult. Such cases may be referred to a paediatric centre with an interest in gastroenterology.
It should be remembered that breast fed children have a wider variety of stool frequency, however they may also suffer from cow's milk protein associated colonic dysmotility if the mother is taking dairy produce and often cow's milk protein exclusion is useful in such constipated infants.8,9

Prognosis
Factors associated with poor response to acute evacuation of constipation after 1 week of presentation in the emergency department are: female sex; history of recurrent abdominal pain; duration of primary presenting symptom longer than 2 days and history of previous medical visits for the same symptom. There is no difference in outcome based upon treatment.26
In children with chronic constipation, 50% will be cured after 1 year and 65-70% after 2 years 2. Two studies show 34 - 37% still to be constipated, receiving laxatives or soiling 3 to 12 years after start of treatment.3,6
Constipated children < 2 years of age at presentation, respond better to treatment than children > 2 years of age.3 Treatment should be given early to prevent development of severe constipation or faecal soiling or both.11

SOME USEFUL INTERNET SITES
1. http://www.digestivedisorders.org.uk/leaflets/constip.html Fact Sheet from Digestive Disorders Foundation UK
2. http://victorvalley.com/health&law/hlaw-feb/matney.htm By Glenn P. Matney, M.D. Flush with success - A Guide to successful potty training
3. http://hcd2.bupa.co.uk/fact_sheets/mosby_factsheets/potty_training.html Site by BUPA about potty training.
4. http://choc.fmpdatabase.net/dev/pediatric/hhg/bsoiling.htm Website by children's Hospital of Orange County. Written by B.D. Schmitt, M.D.
5. http://www.vh.org/Patients/IHB/Peds/Diet/Constipation.html Children's hospital of Iowa. Peer reviewed by Children's hospital of Boston
6. http://www.hsc.virginia.edu/cmc/tutorials/constipation/causecon.htm Children's Medical Center, University of Virginia.

TABLES
Table 1. Indications for referral to hospital

History
Acute:
* Abdominal distension, large faecal mass
* Vomiting
* Blood PR (usually coating the stool or on the paper)

Chronic:
* Failure to thrive
* Features of atopy
* Severe constipation

Past History
History of delayed passage of meconium with constipation in the first month of life

Examination
Any spinal (tuft of hair) abnormality
Lower limb abnormality (wasting, decreased tone)
Anal abnormality (stenosis/anteriorly displaced anus/gush of air or liquid stool on withdrawal of finger after a per rectal examination)

Table 2 - Some useful investigations for organic causes of constipation

Blood
* FBC
* CRP
* Coeliac serology
* Ca
* Thyroid function tests
* Lead levels
Other
* Urine culture
* Sweat test
* Rectal biopsy
* Colonic transit studies (only in selected cases)
* Rectal manometery (severe constipation with a negative biopsy)
Radiology
* AXR
* Spinal US
* MRI - spine



Table 2 - Common Drugs used for Acute Evacuation in a hospital setting 27
Drug + License
Dose
Caution
Sodium Picosulphate
(Powder - sachets)

> 2 year
Contents of one sachet are dissolved in 25 mls of water. After 5 minutes dilute to approximately 150 mls

1-2 years = 1/4 sachet am and 1/4 sachet pm
2-4 years = 1/2 sachet am and 1/2 sachet pm
4-9 years = 1 sachet am and 1/2 sachet pm
>9 years = 1 sachet am and 1 sachet pm
Do not use in:
* Bowel obstruction
* Hypokalaemia
Polyethylene Glycol
(Klean-prep)

Not to use in < 20kg
1 sachet is added to 1 litre of water.
10 ml/kg/hour for 30 minutes then 20 ml/kg/hr for 30 minutes then increase to 25 ml/kg/hr if well tolerated.
Max. Dose is 100 ml/kg over 4 hours or 4 litres whichever is smaller. Review after 4 hours and may be repeated for another 4 hours if needed.

May add pro-kinetics to help in gastric emptying
Do not use in:
Intestinal obstruction.
Paralytic ileus

May cause
Fluid overload or dehydration
Electrolyte imbalance
Hypoglycaemia
Allergic reactions are rare
Polyethylene Glycol sachets
(Movicol)

Not licensed
9 years = 1 sachet 3 times/ day
4-9 years = 1/2 sachet 3 times /day
2-4 years = 1/2 sachet 2 times /day
(We follow this regime in our hospital for acute evacuation)

As above
Phosphate
Enemas (Fleet)

> 3 years
These are used for severe distal faecal blockage.
3-7 years = 1/3 - 1/2 enema
7-12 years = 1/2 - 3/4 enema
> 12 years = 3/4 - 1 enema

Fluid imbalance Hyperphosphataemia Hypocalcaemia
Hypernatraemia
Acidosis

Table 3 - Common Drugs Used for Maintenance Treatment 27
STIMULANTS
Drugs
Dose
Cautions
Docusate Sodium

= 3 years
3 times/day

6 months = 2.5 mg/kg
2-12 years = 2.5 mg/kg
12-18 years = 100mg
DO NOT USE WITH LIQUID PARAFFIN (Docusate causes systemic absorption of oil due to its surfactant properties)
Senna (liquid)

= 2 years
Once at night

1m - 2years = 5ml/kg
2 - 6 years = 2.5 - 5ml
6 - 12 years = 5 - 10 mls

Dependence may develop
Idiosyncratic hepatitis
Melanosis coli - resolves 4-12 months after stopping treatment

Not to be used in
Intestinal obstruction
Hypokalaemia
Sodium Picosulphate (sachets)
As above - to use on weekends (Friday and Saturday evenings)
As above
Glycerine
Suppositories

Safe. Can be used even in premature babies. NOT RECOMMENDED FOR MORE THAN VERY SHORT TERM USE


OSMOTIC LAXATIVES 27

Drugs
Dose
Cautions
Lactulose - semi synthetic
disaccharide
Used twice a day

< 1 yr = 2.5 ml
1-5 years = 5 mls
5 - 10 years = 10 mls
10 - 12 years = 15 mls

Not to be used in:
Galactosaemia, or
Intestinal Obstruction

May give:
Flatulence
Cramps
Abdominal pains
Polyethylene Glycol
Sachets
(Movicol)
Unlicensed
Preferably used in children above 8 years of age
1 sachet /day over weekends
As above


FAECAL SOFTENERS 27

Drugs
Dose
Cautions
Paraffin
oil


2 - 12 years = 0.5 - 1 ml/kg

Lipoid pneumonia if swallowing mechanisms compromised.

DO NOT USE WITH DOCUSATE
(Docusate causes systemic absorption of oil due to its surfactant properties)





REFERENCES:
1. Weaver LT, Steiner H. The bowel habit of young children. Arch.Dis.Child 1984; 59(7): 649-52.
2. Loening-Baucke V. Chronic constipation in children. Gastroenterol 1993; 105(5): 1557-64.
3. Loening-Baucke V. Constipation in early childhood: patient characteristics, treatment, and long term follow up. Gut 1993; 34(10): 1400-4.
4. Baker SS, Liptak GS, Colletti RB, Croffie JM, Di Lorenzo C, Ector W et al. Constipation in infants and children: evaluation and treatment. A medical position statement of the North American Society for Pediatric Gastroenterology and Nutrition. J.Pediatr.Gastroenterol.Nutr. 1999;29(5):612-26.
5. Loening-Baucke V. Biofeedback treatment for chronic constipation and encopresis in childhood: long-term outcome. Pediatrics 1995; 96: 105-10.
6. Keuzenkamp-Jansen CW, Fijnvandraat CJ, Kneepkens CMF, Douwes AC. Diagnostic dilemmas and results of treatment for chronic constipation. Arch Dis Child 1996;75(1):36-41.
7. Ghosh A, Griffiths DM. Rectal biopsy in the investigation of constipation. Arch.Dis.Child 1998; 79(3): 266-8.
8. Iacono G, Cavataio F, Montalto G, Florena A, Tumminello M, Soresi M et al. Intolerance of cow's milk and chronic constipation in children. N.Engl.J.Med. 1998; 339(16): 1100-4.
9. Murch S and Walker-Smith JA. Gastrointestinal food allergy. Diseases of the Small Intestine in Childhood 4th edition, Isis Medical Media 2001.
10. Howe AC, Walker CE. Behavioral management of toilet training, enuresis, and encopresis. Pediatr.Clin.North Am. 1992; 39(3): 413-32.
11. Clayden GS. Management of chronic constipation. Arch.Dis.Child 1992; 67(3): 340-4.
12. Hamilton D, Mulcahy D, Walsh D, Farrelly C, Tormey WP, Watson G. Sodium picosulphate compared with polyethylene glycol solution for large bowel lavage: a prospective randomised trial. Br.J.Clin.Pract. 1996; 50(2): 73-5.
13. Staiano A. Use of polyethylene glycol solution in functional and organic constipation in children. (Review). Italian journal of Gastroenterol and Hepatol.1999; 31 Suppl 3:S260-3.
14. Sondheimer JM, Gervaise EP. Lubricant versus laxative in the treatment of chronic functional constipation of children: a comparative study. J Pediatr Gastroenterol Nutr 1982; 1(2): 223-6.
15. Lee WS, Fabiani E, Beattie RM, Meadows N, Phillips AD, and Walker-Smith JA. Liquid Paraffin: a gentle approach to severe constipation in childhood. Illustr Case Reports in Gastroenterol. 1995; 2, 101-106. Chapman and Hall.
16. Tolia V, Lin CH, Elitsur Y. A prospective randomized study with mineral oil and oral lavage solution for treatment of faecal impaction in children. Aliment Pharmacol Ther 1993: 7:523-529.
17. Clayden GS. Dioctyl sodium sulphosuccinate in constipation [letter]. Lancet 1978;2(8093):787.
18. Tzavella K, Schenkirsch G, Riepl RL, Odenthal KP, Leng-Peschlow E, Muller-Lissner SA. Effects of long-term treatment with anthranoids and sodium picosulphate on the contents of vasoactive intestinal polypeptide, somatostatin and substance P in the rat colon. Eur J of Gastroenterol & Hepatol. 7(1): 13-20,1995 Jan.
19. Nusko G, Schneider B, Schneider I, Wittekand Ch, Hahn EG. Anthranoid laxative abuse is not a risk factor for colorectal neoplasia: results of a prospective case control study. Gut 2000; 46(5): 651-655.
20. Muller-Lissner S. What has happened to the cathartic colon? Gut 1996; 39(3): 486-488.
21. Nurko S. Advances in the management of pediatric constipation. Curr.Gastroenterol.Rep. 2000;2(3):234-40.
22. Corazziari E, Badiali D, Bazzocchi G, Bassotti G, Roselli P, Mastropaolo G et al. Long term efficacy, safety, and tolerabilitity of low daily doses of isosmotic polyethylene glycol electrolyte balanced solution (PMF-100) in the treatment of functional chronic constipation. Gut 2000;46(4):522-6.
23. Attar A, Lemann M, Ferguson A, Halphen M, Boutron MC, Flourie B et al. Comparison of a low dose polyethylene glycol electrolyte solution with lactulose for treatment of chronic constipation. Gut 1999;44(2):226-30.
24. Jensen SL. Treatment of first episodes of acute anal fissure: prospective randomised study of lignocaine ointment versus hydrocortisone ointment or warm sitz baths plus bran. Br.Med.J. (Clin.Res.Ed) 1986; 292(6529): 1167-9.
25. Schouten WR, Briel JW, Boerma MO, Auwerda JJ, Wilms EB, Graatsma BH. Pathophysiological aspects and clinical outcome of intra-anal application of isosorbide dinitrate in patients with chronic anal fissure. Gut 1996; 39(3): 465-9.
26. Patel H, Law A, Gouin S. Predictive factors for short-term symptom persistence in children after emergency department evaluation for constipation. Arch.Pediatr.Adolesc.Med. 2000; 154(12): 1204-8.
27. Royal College of Paediatrics and Child Health. Medicines for children. London: RCPCH Publications Limited, 1999.