Constipation

by Dr Sarah Little, General Practitioner MBChB BSc Hons MRCGP DCH DRCOG DFSRH


Primary care Diagnosis and Management of Idiopathic Constipation in Infants

A review of childhood constipation and its management as a whole is outwith the scope of this platform and is covered comprehensively by NICE guidance1. Rather the focus here will be idiopathic constipation in babies up to the age of 1 year, particularly in relation to infant feeding. The majority of cases of infant constipation are idiopathic, though the differential diagnosis is wide. Management of idiopathic constipation in infants is prone to conflicting advice and there is a poor evidence base.

Infrequent stooling in the first 2 weeks of life is a red flag. It may be associated with inadequate calorie intake and is a predictor of poor infant weight gain. It is an indicator for arranging for the baby to be weighed and referring for a feeding assessment and paediatric review.


Normal infant stools prior to introduction of complementary foods

Normal breastfed infant stools are mustard in colour (resulting from bilirubin in bile), grainy in texture and runny. They have a sweet, not unpleasant odour. By day 5, a breastfed baby should be passing at least 2 of these stools per day. Normal formula fed infant stools are yellow to brown, and thicker.


History taking to diagnose constipation in a child under 1 year (adapted from NICE guidance)1

2 or more findings indicate constipation:

  • Fewer than three complete stools per week (this does not apply to exclusively breastfed babies after 6 weeks of age)
  • Hard large stool
  • Rabbit dropping stools
  • Distress on stooling
  • Bleeding associated with hard stool
  • Straining
  • Previous episode(s) of constipation
  • Previous or current anal fissure

Note that exclusively breastfed babies start to space out their stooling from around 3 weeks of age, as the gastro-colic reflex becomes less sensitive. A range of breastfeeding resources report it as normal for exclusively breastfed babies to have periods of 7-10 days between stools after 6 weeks of age as long as the baby is well and gaining weight (e.g. See the NHS resource Start4Life). Idiopathic constipation is rare in exclusively breastfed babies.

Chronic constipation is constipation lasting more than 8 weeks1.

Red flags (adapted from NICE guidance)1, 2

To enable a diagnosis of idiopathic constipation, red flags need to be excluded:

  • Symptoms since birth or within 2 weeks of birth
  • Delayed passage of meconium (>48 hours in term infant)- may indicate Hirschsprung’s disease or cystic fibrosis
  • Passage of ribbon like stools- may indicate anal stenosis (more likely to present in a child younger than 1 year)
  • Abdominal distension and vomiting
  • Abnormal appearance of anus (e.g. fistulae, multiple fissures, tight or patulous anus, anteriorly placed anus, absent anal wink)
  • Abnormalities of lower spine or gluteal region (e.g. discoloured or hairy patch, sinus or sacral pit, asymmetry of gluteal muscles, sacral agenesis)
  • Unexplained weakness or deformity of lower limbs; history of locomotor delay
  • Family history of Hirschsprung’s disease

Amber flags (adapted from NICE guidance)1, 2

Amber flags require referral for further investigation and specialist assessment/input alongside primary care:

  • Faltering growth, developmental delay or concerns about wellbeing
  • Evidence or possibility of child maltreatment
  • Constipation triggered by the introduction of cows’ milk

Dyschezia

The current Rome IV definition for infant dyschezia is straining and crying for at least 10 minutes before successful passage of soft stools in an infant younger than 9 months of age without any other health problem3. This is often associated with infants turning red or purple in the face during defecation.

The explanation for infant dyschezia is lack of coordination between increased intra-abdominal pressure preceding defecation and relaxation of the pelvic floor. Symptoms usually start in the first months of life and resolve spontaneously after a few weeks. Parents can be reassured that it is a benign condition and that the prescription of laxatives should be avoided4.  Dyschezia is underrecognised and often mistreated as constipation5.


Cows’ Milk Allergy

Constipation is one of the possible presentations of non-IgE mediated CMA, but would rarely present in isolation.


Coeliac Disease

Once gluten is introduced into the diet at around 6 months, infants with a genetic susceptibility for coeliac disease may develop it as early as 9 months. Constipation is one of the possible presentations of coeliac disease in children, though more commonly infants may present with chronic diarrhoea, poor feeding, abdominal distension, abdominal pain and faltering growth. Coeliac disease has a prevalence of 1:100 in the UK and approximately 90% of cases remain undiagnosed6. Currently, there is no evidence on the optimal breastfeeding duration or the effects of avoiding the early or late introduction of gluten in children at risk of developing coeliac disease7. If a first degree relative has coeliac disease, there is a 1:10 chance of the child developing it6.


History taking to establish a positive diagnosis of idiopathic constipation in a child under 1 year (adapted from NICE guidance)1

  • Starts after a few weeks of life
  • Obvious precipitating factors coinciding with the start of symptoms: fissure, change of diet, infections
  • Normal passage of meconium
  • Generally well, weight and length within normal limits
  • Normal locomotor development
  • Changes in infant formula, weaning, insufficient fluid intake

When to refer to secondary care

  • Any infant with a red or amber flag (but see CMA page for when to refer if this is the suspected cause)
  • Any infant who has not responded to the recommended dose of laxatives within 4 weeks of optimal treatment (urgently if under 1 to exclude Hirschsprung’s disease)
  • Any infant who has not responded to a disimpaction regimen2

Examination includes perianal inspection (especially important if there is an early history of constipation), spine and lower limb examination. If a digital rectal examination is indicated this should be undertaken only by ‘healthcare professionals competent to interpret features of anatomical abnormalities or Hirschsprung’s disease’1.

Screening bloods are usually done in secondary care and include thyroid function and coeliac screen (FBC, renal function, LFT, glucose, calcium, magnesium, phosphate and CRP may also be relevant).


Laxatives

All infants should be assessed for faecal impaction and if required, treated according to disimpaction regimes.

Prescribing guidelines for laxatives and their doses for disimpaction and maintenance vary between regions. A summary of treatment recommendations is available in NICE guidance1, 2. Commonly used laxatives are discussed below:

Movicol ® Paediatric or Cosmocol Paediatric (macrogols)

These are osmotic laxatives containing macrogol (polyethelyne glycol). Macrogols have been in use for the past two decades and has been a game-changer in the management of paediatric constipation. It has evidence-based efficacy and tolerability although it is worth noting that it is not licensed in infants (but commonly prescribed). It can be mixed into any hot or cold beverage and even mixed into jelly. A parent sheet on how to prepare macrogols is available here. The dose is ½ to 1 sachet daily for both disimpaction and maintenance for infants under 1 year. Onset on action is usually 1-2 days.

Lactulose

Lactulose is another osmotic laxative. The dose of lactulose for infants under 1 year is 2.5mls twice daily adjusted to response (not licensed under 1 month). Lactulose is metabolised by colonic bacteria into fatty acids. Increasing the dose eventually results in a plateau as the metabolic capacity of the colon becomes saturated. Gases produced as a by-product can cause side effects of bloating and flatulence. Teeth should be brushed after lactulose as it is a dissacharide. Onset of action is usually 1-2 days. There are no studies comparing lactulose to placebo8.

Glycerin (Glycerol) suppositories

Glycerin suppositories have both osmotic and stimulant effects. They are mainly used as stimulant laxatives in neonates in Neonatal Intensive Care Units, to encourage gut motility (where oral laxatives are contraindicated). They are available over the counter and are sometimes used in older babies. They should be inserted apex end first in order to be placed against the bowel wall as opposed to in the middle of faecal matter (where they would remain intact). It is best to avoid reliance on them long term as this could interfere with rectal emptying habits.


Diet and fluids

Dietary interventions alone should not be first line treatment for idiopathic constipation, rather as an adjunct to laxatives1. Once complementary foods are started, a diet rich in fruit, vegetables, fibre and sufficient fluid is important.

NICE guidance1 did not find evidence that any of the formulas they reviewed are clinically effective in the treatment or management of constipation. It also suggests that the common practice of switching from one infant formula to another to alleviate constipation may be detrimental, introducing delay in treating infants with laxatives.

Precipitating factors for idiopathic constipation may include drugs2 (e.g. alginates used for GORD9).

Extra water: to give or not give?

Exclusively breastfed babies do not require any water until such time as they are started on complementary foods around 6 months. Breastmilk is 88% water. Displacing feeds with water may impact on milk supply (unless it is just a few sips whilst learning to use a free-flowing breaker).

Infant formula should always be made up at the correct concentration. For formula fed babies up to 6 months, small amounts of cooled, previously boiled water can temporarily be given in addition to feeds on hot days10.

At age 7-12 months, babies require 600 mls water per day from drinks (i.e. from milk and beverages)1, 2. Increasing fluids beyond this does not further improve or prevent constipation. Higher total water may be required however if children are physically active, exposed to hot environments, or obese.

Mineral water is not recommended due to higher sodium and sulphate levels10.

Fruit juice: to give or not give?

Apple, pear, and prune juices contain sorbitol which acts as a natural laxative. Prune juice also contains fibre. Offering orange juice is commonly advised by health care professionals for constipation though there is no evidence base for this practice and conflict with recommendations for introduction of solid foods at around 6 months.

General advice for suitable drinks for babies is given on the NHS website.


Alternative therapies

It is often recommended to try clockwise abdominal massage. NICE guidance has not found evidence of efficacy in abdominal massage1, but anecdotally it is helpful and harmless. More research is needed.


Conclusion

Constipation is often under-treated, and timely optimal management will help prevent or limit the duration of chronic constipation. Consideration of dyschezia, especially in exclusively breastfed babies, may avoid unnecessary treatment with laxatives.

Thanks to Dr Warren Hyer, Consultant Paediatrician & Consultant Paediatric Gastroenterologist at Northwick Park & St Mark’s Hospital, Middlesex for his advice and guidance and Dr Victoria Thomas, Consultant Paediatrician for editorial support.


Further Information

NICE Guideline CG99: Constipation in Children and Young People- Diagnosis and Management Updated July 2017

NICE CKS: Constipation in Children June 2019

Eric: How to Prepare Macrogol Laxatives Includes a downloadable pdf patient information leaflet

Eric: The Children’s Bowel and Bladder Charity

Eric: How to Treat Constipation


References

  1. NICE Guideline CG99 Constipation in children and young people: diagnosis and management. May 2010, updated July 2017
  2. NICE CKS: Constipation in children June 2019
  3. Zeevenhooven J, Koppen I, Benniga M. The New Rome IV Criteria for functional Gastrointestinal Disorders in Infants and Toddlers, Pediatr Gastroenterol Hepatol Nutr. 2017; March 20(1):1-13.
  4. Kramer E, den Hertog-Kuijl JH, van den Broek LM, van Leengoed E, Bulk AM, Kneepkens CM, Benninga MA. Defecation patterns in infants, a prospective cohort study, Archdischild. 2015; 100:533–536.
  5. Vandenplas Y, Abkari A, Bellaiche M, Benninga M, Chouragui JP, Cokura F et al. Prevalence and Health Outcomes of Functional Gastrointestinal Symptoms in Infants From Birth to 12 Months of Age. J Pediatr Gastroenterol Nutr 2015; 61:531–537.
  6. Murch S, Jenkins H, Auth M, Bremner R, Butt A, France S, Furman M, Gillett P, Kiparissi F, Lawson M, McLain B, Morris M, Sleet S, Thorpe, M. Joint BSPGHAN and Coeliac UK guidelines for the diagnosis and management of coeliac disease in children. Arch Dis Child. 2013; 98: 806-811.
  7. Silano M, Agostoni C, Sanz Y, Guandalini S. Infant Feeding and Risk of Developing Celiac Disease: a systematic review, BMJ Open. 2015-009163.
  8. Gordon M, MacDonald J, Parker C, Akobeng A, Thomas A. Osmotic and Stimulant Laxatives for the Management of childhood constipation (review), Cochrane Database of Systematic Reviews 2016 (online).
  9. Medicines for Children: Gaviscon for for gastro-oesophageal reflux disease
  10. NHS Website: Drinks and cups for babies and young children

Published 17th January 2020