Introduction

Idiopathic constipation is often seen as a minor problem which will either spontaneously resolve or respond to extra fibre and fluids in the diet. Parents often feel that it is their fault and that the significance of idiopathic constipation is overlooked. They also find difficult to accept that constipation could be idiopathic and worry that it is an indicator of a more serious underlying health problem. For the child or young person, as well as for their families, the impact of idiopathic constipation on all aspects of their lives should not be underestimated.

A thorough and complete history-taking is the most essential part of the initial process of diagnosis and treatment of idiopathic constipation. The first step in this process is to exclude other medical conditions and to facilitate a speedy diagnosis of idiopathic constipation. Careful history-taking alongside the physical examination should identify the ‘red flags’ that would suggest that the constipation is from an organic cause that requires further investigation. A positive diagnosis of idiopathic constipation will allow for correct and timely interventions and will prevent repetitive and often unnecessary investigations.

Accurate record keeping will allow this history to accompany the child or young person on the patient journey to avoid unnecessary duplication of questioning and to facilitate a clear and holistic picture of the presenting condition.

Health professionals need to be aware of the social consequences of what may seem to be a trivial condition and the importance of their role in the early recognition of idiopathic constipation. In doing so they will benefit children and young people and their families and help prevent the long-term effects of idiopathic constipation.

Clinical question

What are the key components of the history-taking and the physical examination that would indicate idiopathic constipation or flag a serious underlying disorder?

Studies considered in this section

Studies were considered if they:

• included neonates, infants, or children or young people up to their 18th birthday with chronic idiopathic constipation
• included key components of the history-taking and the physical examination that would indicate idiopathic constipation or flag a serious underlying disorder such as:

  –

  Hirschsprung's' disease

  –

  coeliac disease

  –

  hypothyroidism

  –

  anorectal malformations

  –

  neurological conditions

  –

  abdominal tumours

• included the following outcomes

  –

  changes in frequency of bowel movements

  –

  changes in stools consistency or appearance

  –

  changes in pain or difficulty on passing stools

  –

  changes in frequency of episodes of soiling

  –

  reduction in laxatives use

  –

  parent/child views or quality of life

• were not case reports
• were published in English.

No restrictions were applied on the publication date or country.

Overview of available evidence

The searches identified 487 articles and 16 articles were retrieved for detailed assessment. Of these, 3 studies were identified for inclusion in this review.

Narrative summary

One retrospective case–control study performed in the USA³ (2003) [EL=III] determined the precipitants of constipation in early childhood. One hundred and twenty-five children (age 44 months ± 13, 49% boys) were recruited for the patient group from 26 primary care centres after visiting their primary care physician with a chief complaint of constipation for the first time. The controls were 95 children who had no history of constipation (mean age 46 months ± 18, 54% male) including 22 non-constipated patient siblings, who were recruited when their constipated siblings were recruited, and 73 non-sibling children recruited though advertisements. Constipation was defined as the passage of fewer than 3 bowel movements each week for at least 2 consecutive weeks.

Parents of patients and controls were asked to fill out a questionnaire about the child's bowel habits. Parents indicated how difficult toilet training had been using a Likert scale (ranging from 0 indicating not at all difficult to 4 indicating extremely difficult). Parents of the constipated children indicated which events (from a list of 18) occurred in the 3 months prior to onset of constipation, and which of these they felt had contributed to the child becoming constipated.

Results of the questionnaires showed no statistically significant differences for either family history of constipation or initial age of toilet training between constipated children and healthy controls. A high degree of difficulty with toilet training (mean score 2.1 ± 1.3 versus 1.4 ± 1.1; P < 0.001), a degree of difficulty and pain in passing bowel movements and the child expressing worry about passing bowel movement (75% of children versus 8%; P < 0.001) were more likely to have occurred in the constipated children than in the healthy controls.

Children were grouped according to whether they became constipated before or after their second birthday. Parents of children in the two groups reported similar events having occurred in the 3 months before the onset of constipation, with the following exceptions:

• toilet training having occurred more often before constipation in the older children (40% versus 20%)
• making the dietary transition from breast to bottle and from liquid to solid diets having occurred more often before constipation in the younger children (30% versus 0%).

Large or painful bowel movements were identified as by far the most frequent precipitating event for both age groups. Toilet training was seen as more of a precipitant for older onset children (20% versus 10%), whereas transition from breast to bottle and from liquid to solid foods was seen to be more of a problem for younger onset children (25% versus 0%). No attrition or loss to follow up was reported.

One retrospective case series performed in a tertiary referral centre in Canada¹⁵ (2009) [EL=III] determined what proportion of children evaluated in an emergency department (ED) because of crying had a serious underlying etiology as well as the individual contributions of history, physical examination and laboratory investigations in determining diagnosis. Of 37,549 ED visits that occurred during a 9 month eligibility period, 238 children (124 boys [52%], median age 2.3 months, age range 1.0 to 5.4) met the inclusion criteria of being 12 months or younger, being afebrile (less than 38°C) and presenting with a chief complaint of crying. Charts were reviewed retrospectively by searching the electronic database using a chief complaint family word root search for: ‘cry’, ‘irritable’, ‘fuss’, ‘scream’ and ‘colic’. The relevant histories were analysed to establish the final diagnosis and to find out the contribution of history, examination and investigations to the final diagnosis. The final diagnosis was found by positive findings on history and/or physical examination alone in 66.4% (158 of 238) of children.

Constipation was diagnosed in 11 children, all of whom were diagnosed by history and examination alone. The features in history and physical examination considered to be helpful in diagnosis of constipation were: a history of difficult, infrequent, hard stools and palpation of small pellets on abdominal examination. Within the sample, abdominal radiograph was performed 14 times with no positive findings. Abdominal ultrasound was performed 16 times with two positive findings (12.5%), which contributed to the diagnosis of intussusception and acute cholecystitis in two cases, but no constipation. It should be noted that due to the lack of a uniform testing protocol these results may not be generalisable to other settings.

A retrospective cohort conducted in the USA¹⁶ (2003) [EL=II] tested the hypothesis that key features in the history, physical examination and radiographic evaluation would enable unnecessary rectal biopsies to be avoided. Two cohorts of 315 children were identified. Cohort 1 comprised 265 children presenting with constipation who had undergone rectal biopsy to diagnose Hirschsprung's disease (HD). Cohort 2 comprised a concurrent selected cohort of 50 children with idiopathic constipation (IC). Only patients with definite information were included, so the number of patients in each analysis varies due to missing data.

Delayed passage of meconium was defined as failure to pass meconium in the first 48 hours of life. These data were available in 59% of cases. Abdominal distension was determined from parental response to a questionnaire or data noted during patients' visits. Enterocolitis was defined as diarrhoea associated with fever.

In the group where the onset of constipation occurred when they were under 1 year, significantly more children with HD reported delayed passage of meconium compared to children with IC (65% versus 13%; P < 0.05). Abdominal distension and vomiting were also reported in significantly more children with HD compared to children with IC (abdominal distension in 80% versus 42%; P < 0.05 and vomiting in 72% versus 21%; P < 0.05). Faecal impaction requiring manual evacuation occurred in significantly more children with IC compared to children with HD (30% versus 6%; P < 0.05). There were no significant differences between children with HD and children with IC regarding enterocolitis. In the group where onset of constipation occurred after the children were 1 year, significantly more children with HD reported delayed passage of meconium compared to children with IC (81% versus 1%; P < 0.05) and also significantly more children with HD reported abdominal distension compared to children with IC (53% versus 7%; P < 0.05). No children with IC experienced vomiting whereas 23% of children with HD did (P < 0.05). There were no significant differences between children with HD and children with IC regarding enterocolitis or faecal impaction requiring manual evacuation.

Evidence statement

One retrospective case–control study [EL=III] showed that certain features were significantly more likely to have occurred in the constipated children than in the healthy controls:

• a high degree of difficulty with toilet training
• difficulty and pain in passing bowel movements
• the child expressing worry about passing bowel movements.

There were no significant differences in either family history of constipation or initial age of toilet training between the constipated children and the healthy controls. Toilet training was seen as more of a precipitant in the children who became constipated after their second birthday and transition from liquid to solids was seen as more of a precipitant in children who became constipated before their second birthday. Large or painful bowel movements were seen as by far the most frequent precipitating event for both age groups.

One retrospective case series [EL=III] showed that in a group of children evaluated in an emergency department because of crying, all children diagnosed with constipation were diagnosed by history and examination alone. The criteria used to diagnose constipation were a history of difficult, infrequent, hard stools and palpation of small pellets on abdominal examination.

One retrospective cohort study [EL=II] showed that significantly more children with HD reported delayed passage of meconium, abdominal distension and vomiting compared to children with idiopathic constipation. In children younger than 1 year faecal impaction requiring manual evacuation occurred in significantly more children with idiopathic constipation compared to children with HD, but there were no significant differences between the two groups for children older than 1 year regarding this clinical feature. There were no significant differences between children with HD and children with idiopathic constipation regarding enterocolitis. The average age of patients with HD when symptoms started was 8 months (range 1 day to 9 years) and for patients with idiopathic constipation it was 15 months (range 7 days to 16 years).

GDG interpretation of the evidence

It is the GDG's view that both history-taking and physical examination constitute essential steps in the diagnosis of any medical condition in general and of idiopathic constipation in particular. This is supported by the GDG's professional experience and also evidence obtained from the review. However, the GDG noted that there is insufficient evidence to allow it to identify all the key components that would comprise a comprehensive history-taking and physical examination that would indicate idiopathic constipation or flag a serious underlying disorder.

In order to complete the identification of all key components of history-taking and physical examination, formal consensus methodology was employed among the GDG members. First they were asked them to identify what they thought these components might be and then there were two rounds of consensus voting in order to agree which ones should be included in the guideline as key components.

Introduction

The digital rectal examination (DRE) is recommended by a number of national and international guidelines as part of the routine examination of children with chronic constipation.^17,18,19

However, there is doubt as to its value in the assessment of children with chronic constipation. It is an investigation that is often not well tolerated by children or their parents.

Rarely, it may be necessary to perform a DRE to exclude an anatomical cause of constipation, for example anal stenosis.

In this section we shall look at the evidence base regarding the value of this examination in children with chronic constipation.

Clinical question

What is the diagnostic value of the DRE in children with chronic idiopathic constipation?

Studies considered in this section

Studies were considered if they:

• included neonates, infants or children up to their 18th birthday with chronic idiopathic constipation undergoing DRE
• were not case reports
• were published in English.

No restrictions were applied on the publication date or country.

Overview of available evidence

The searches identified 79 articles and 11 articles were retrieved for detailed assessment. Of these, two case series were identified for inclusion in this review.

Narrative summary

One prospective case series conducted in the USA²⁰ (2001) [EL=3] aimed to determine whether clinical variables accurately identify children with radiologically proven constipation. The study involved 251 children aged 2 to 12 years who presented to the emergency department (ED) with abdominal pain and underwent an abdominal radiograph. Clinical variables (as a model) showed a sensitivity of 77%, a specificity of 35%, a positive predictive value of 60% and a negative predictive value of 55%. Only the following clinical variables were significantly different between the groups of children who were shown to be constipated as per abdominal radiography and those who were not:

• history of normal/hard stool consistency (group 1: 74% (100 out of 135), group 2: 61% (61 out of 99); P = 0.016)
• absence of rebound tenderness (group 1: 98% (138 out of 141), group 2: 90% (99 out of 110); P = 0.007)
• presence of left lower quadrant tenderness (group 1: 20% (19 out of 96), group 2: 9% (6 out of 69); P = 00499)
• stool present in rectal vault as per rectal exam (group 1: 69% 70 out of 102, group 2: 43% (29 out of 68); P = 0.008).

No clinical variable, either as a single variable or in a model, accurately identified patients with abdominal pain and radiographically proven constipation. One single variable, stool present on rectal exam, was the best discriminator between patients with and without constipation. The model accurately predicted 77% of patients with radiographically proven constipation: however, 35% of the patients predicted by the model as radiographically constipated actually had other diagnosis. It should be noted that 32% of the enrolled children did not undergo a rectal examination.

A retrospective case series also conducted in the USA²¹ (1995) [EL=3] aimed to determine if the presence of faecal retention in encopretic children on presentation could be assessed objectively using a plain abdominal radiograph and whether faecal retention so determined correlated with findings at initial clinical assessment. The population sample comprised 60 children aged 4 to 18 diagnosed with encopresis as defined by the DSM Revised Third Edition:

‘Repeated involuntary (or, much more rarely, intentional) passage of faeces into places not appropriate for that purpose (e.g. clothing or floor)…the event must occur at least once a month for at least 6 months, the chronological and mental age of the child must be at least 4 years, and physical disorders that can cause faecal incontinence, such as aganglionic megacolon, must be ruled out.’

Forty-seven encopretic children were diagnosed with faecal retention by radiographic criteria on presentation, whereas 13 encopretic children showed no evidence of faecal retention by radiographic criteria on presentation. When the diagnosis of retention by abdominal radiography (systematic reading) was made by agreement of at least two radiologists, the diagnosis of retention by rectal examination showed a sensitivity of 88.6%, a specificity of 41.6%, a positive predictive value of 84.8% and a negative predictive value of 50%. When the diagnosis of retention by abdominal radiography (systematic reading) was made by agreement of three radiologists, the diagnosis of retention by rectal examination showed a sensitivity of 91.7%, a specificity of 71.4%, a positive predictive value of 94.3% and a negative predictive value of 62.5%. There were no significant differences between encopretic children whose abdominal radiography were reviewed for the study and those who did not have radiography or whose radiography could not be retrieved.

Children with retention (as per radiography) were significantly more likely to have stool in the rectum on presentation (P = 0.015) and were significantly less likely to have parents report a difficult toilet training (P = 0.018). There were no other significant differences between the two groups regarding the rest of the variables measured. (Not all data were available for every child).

Evidence statement

One prospective case series [EL=3] showed that stool present on rectal examination as diagnosed per DRE was the best discriminator between patients with and without radiographically diagnosed constipation.

One retrospective case series [EL=3] showed good sensitivity and positive predictive value of the DRE in children diagnosed with faecal retention by radiography, but its specificity and negative predictive value were poor.

GDG interpretation of the evidence

The GDG noted that there is a lack of good quality evidence on the diagnostic value of DRE in children with chronic constipation. The GDG concluded from the evidence that DRE is not useful for the diagnosis of faecal impaction in chronic idiopathic constipation. However, based on their clinical experience, the GDG is aware that DRE is useful to help diagnose other serious problems, for example anal stenosis and HD. The younger the child is, the more important it is that a DRE is carried out, as these serious problems are more frequently diagnosed in younger children, particularly children under 1 year. However, older children who have other relevant clinical features may also require these diagnoses to be excluded.

The GDG concluded that faecal retention/impaction can be diagnosed by taking an appropriate history, asking the parents about the presence of overflow soiling and bowel habits and by the detection of palpable faeces on abdominal examination.

It is the GDG's view that a DRE should only be undertaken for diagnosis of constipation in children by healthcare professionals who are competent to do so.

Ideally, if indicated, a DRE should be performed only once for each child. For this reason the GDG believes it is very important to maintain good communication between all healthcare professionals responsible for the child's treatment to ensure that a DRE is not repeated unnecessarily.