Colon Transit Time Test in Korean Children with Chronic Functional Constipation

Dyssynergic Defecation in Chronically Constipated Children in Korea

Purpose

Dyssynergic defecation (DSD) is one of the important causes of chronic constipation in children. We aimed to analyze the clinical features, diagnostic test results, and treatments for DSD in children.

Methods

Children diagnosed with DSD using fluoroscopic defecography were enrolled in this study. Clinical data, including the results of colon transit time (CTT) test and biofeedback (BF) therapy, were collected from medical records retrospectively.

Results

Nineteen children were enrolled. The median age was 9 years (6-18 years), the median frequency of bowel movement was 1/7 days (1-10 days), the median duration of constipation was 7.0 years (2-18 years), the median age of onset of constipation was 2.5 years (1-11 years). In the CTT test, outlet obstruction type was noted in 10/18 (55.6%), slow transit type in 5/18 (27.8%), and normal transit in 1/18 (5.6%). The median CTT was 52 hours (40-142 hours). Initial medical therapy was performed with the polyethylene glycol 4000, and the response was good in 9/19 (47.4%), fair in 9/19 (47.4%), and poor in 1/19 (5.0%). BF was performed in 8/19, with good results in 6/8 (75.0%) children and failure in 2/8 (25.0%) children. After long-term medical therapy (11/19), 3/5 showed good response with medication alone, 6/8 showed good response with BF and medication combined.

Conclusion

DSD should be considered as a cause of chronic constipation in children, especially in those with abnormal CTT test results. BF combined with medical therapy is effective even with age-limited cooperation.

Diagnosis and management of fecal incontinence in children and adolescents

Fecal incontinence (FI) is a commonly occurring disease of high concern. It is characterized by voluntary and involuntary defecation in children and adolescents. It is not only a physical disease but also a psychological and behavioral disorder. FI poses a serious burden on individuals and their families and therefore has become a social problem. Unfortunately, the management of FI among children is still a challenge because the etiology varies widely. Constipation has been found to be the most common cause, while sphincter dysfunction and neurogenic abnormalities may also play a role. Currently, no consensus guidelines exist, and the criteria for selecting optional methods remain unclear. It is therefore necessary to improve the efficacy of diagnosis and management strategies of FI in children. This review focused on the classification and etiology, discussed the diagnosis and management methods of FI in children and adolescents, and aimed to guide future studies.

Subtype classification of functional constipation in children: polyethylene glycol versus lactulose

BACKGROUND

This study aimed to evaluate the usefulness, from a therapeutic perspective, of classifying the subtypes of functional childhood constipation using a colon transit time (CTT) test.

METHODS

A total of 190 children were enrolled in this study, which was based on data collected from a defecation diary, a CTT test, and medical records.

RESULTS

Polyethylene glycol (PEG) 4000 was prescribed in 51.1% (N = 47/92) of normal transit type constipation cases (NT) and 91.8% (N = 90/98) of abnormal transit type constipation cases (P < 0.001). In terms of the subtype of CTT test, PEG 4000 was prescribed in 51.1% (N = 47/92) of NT cases, 96.2% (N = 25/26) of outlet obstruction type cases (OT), and 90.3% (N = 65/72) of slow transit type cases (ST) (P < 0.001). Polyethylene glycol 4000 was administered in 97.2% (N = 35/36) of the fecal incontinence group and 66.2% (N = 102/154) of the non-fecal incontinence group (P < 0.001). In the non-fecal incontinence group, PEG 4000 was prescribed in 47.3% (N = 40/84) of NT cases, 94.4% (N = 17/18) of OT cases, and 86.5% (N = 45/52) of ST cases (P < 0.001). In the fecal incontinence group, PEG 4000 was prescribed in 87.5% (N = 7/8) of NT cases, 100% (N = 8/8) of OT cases, and 100% (N = 20/20) of ST cases (P = 0.165).

CONCLUSIONS

Subtype classification of functional constipation based on the CTT test provides important information for the initial choice of drugs in children.

Value of Fluoroscopic Defecography in Constipated Children With Abnormal Colon Transit Time Test Results

Background/Aims

Colon transit time (CTT) test is regarded as the gold standard for evaluating colon transit function. Fluoroscopic defecography (FD) is a dynamic radiologic test to assess anorectal function. The aim is to evaluate the value of FD in constipated children with abnormal CTT test results.

Methods

Fifty-one children (27 girls) with a mean age of 9.8 ± 3.2 years who met Rome III criteria for constipation and older than 5 years with abnormal CTT test results underwent FD.

Results

Of 51 children, 27 (52.9%) showed positive findings on FD, including pelvic floor dyssynergia (PFD) (10/27, 37.0%), structural abnormality (15/27, 55.6%) (rectocele 53.3%, intussusception 33.3%, and both 13.4%), and both PFD and rectocele (2/27, 7.4%). In terms of CTT test subtype, of 35 children who had outlet obstruction type in CTT test, 19 (54.2%) had positive findings, including PFD (8/19, 42.1%), structural abnormality (9/19, 47.4%) (rectocele 55.6%, intussusception 22.2%, and both 22.2%), and both PFD and rectocele (2/19, 10.5%). Of the 16 children who had slow transit type of CTT test, 8 (50.0%) had positive findings, including PFD (2/8, 25.0%) and structural abnormality (6/8, 75.0%). Of the 6 children who had structural abnormality, 3 (50.0%) had rectocele and 3 (50.0%) had intussusception. For the 2 children (2/16, 12.5%) who had PFD, puborectalis muscle relax failure was found on FD. Puborectalis muscle relax failure was treated with biofeedback and medication. In the minor abnormalities, medication continued without additional therapeutic modalities.

Conclusions

FD was valuable for both diagnoses of underlying causes and interpretation of CTT test results in children with abnormal CTT test results. Therefore, this study suggests that FD and CTT tests should be incorporated into logical thinking for constipation in children.

Clinical Features of Severely Constipated Children: Comparison of Infrequent Bowel Movement and Fecal Soiling Groups

PURPOSE

To compare the clinical features, diagnostic findings, and medications of children with infrequent bowel movements or fecal soiling.

METHODS

This study enrolled 333 children (189 male; age range, 1 month to 18 years) diagnosed with functional constipation by Rome III or IV criteria. We classified them into 3 groups (infrequent bowel movement without fecal soiling [G3-a], infrequent bowel movement with fecal soiling [G3-b], and fecal soiling only [G3-c]) and into 2 subgroups of fecal soiling (G2-b) or not (G2-a). Retrospective data on clinical characteristics, colon transit time (CTT) test results, and medications were collected. The Wilcoxon rank-sum test, Kruskal-Wallis test, Chi-square test, and Fisher's exact test were used for the statistical analysis.

RESULTS

The median age (months) and interquartile range (IQR) was 33 (45) in G3-a, 54 (40) in G3-b, and 73 (48) in G3-c (p<0.0001). G3-c had the latest onset (median, 18; IQR, 18; p=0.0219) and longest symptom duration (24 [24], p=0.0148). PEG 4000 was used in 60.6% (G3-a), 96.8% (G3-b), and 83.2% (G3-c) of patients (p<0.0001). The median age (months) and IQR were 33.0 (45.0) in G2-a and 63.5 (52.5) in G2-b (p<0.0001). G2-b had later onset (median, 12; IQR, 19.5; p=0.0062) and longer symptom duration than G2-a (24 [12], p=0.0070). PEG 4000 was used in 60.6% (G2-a) and 88.3% (G2-b) of children (p<0.0001). No statistically significant intergroup differences were seen in maintenance laxative dose, CTT, or CTT type.

CONCLUSION

Infrequent bowel movement and fecal soiling represent the advanced stage of chronic functional constipation.

Predictive value of colonic transit time indices for differentiating nonnormal from normal sensation in children with chronic functional constipation identified by anorectal manometry

BACKGROUND

Constipation is a common disorder in pediatrics, although the underlying pathogenesis is not fully understood. The current study aimed at evaluating the efficacy of different colonic transit time (CTT) indices for differentiating normal from nonnormal sensation in children with chronic functional constipation identified by anorectal manometry (ARM).

MATERIALS AND METHODS

In this cross-sectional study, 47 children with chronic idiopathic constipation, aged 5-15 years, were studied. The total and segmental CTTs were estimated by administering multiple radiopaque markers for 6 days and performing a single abdominal radiograph on day 7. Anorectal function was evaluated using manometry with an Arhan probe. The predictive value of CTT indices was evaluated by receiver operating characteristic curve analysis. Area under the curve (AUC) along with 95% confidence interval (CI) as well as sensitivity and specificity was calculated.

RESULTS

The mean age of the participants was 8.30 ± 2.99 years, with a mean constipation duration of 2.90 ± 0.46; 28 children were identified with nonnormal sensation. The mean values of CTT indices were statistically significantly longer in the nonnormal sensation patients than that in the normal group (P < 0.001). In addition, the mean values of manometry parameters were statistically significantly higher in nonnormal sensation patients than that in normal group (P < 0.01). Among CTT indices, rectosigmoid CTT (AUC [95% CI] =0.999 [0.99-1]; P < 0.001) with sensitivity = 100% and specificity = 94.7% and total CTT (AUC [95% CI] =0.972 [0.93-1] P < 0.001) with sensitivity = 82.3% and specificity = 100% had the highest predictive values for differentiating nonnormal from normal sensation patients.

CONCLUSION

CTT is a simple and noninvasive technique for classifying patients with constipation. It can be used for identifying children suffering from chronic constipation with nonnormal sensation reliably, instead of ARM. Colonic inertia may be a manifestation of global motility dysfunction. Children with delayed distal colonic transits are more likely to have abnormal defecation dynamics.

Efficacy and Safety of Combined Oral and Enema Therapy Using Polyethylene Glycol 3350-Electrolyte for Disimpaction in Pediatric Constipation

PURPOSE

We evaluated the efficacy and safety of combined oral and enema therapy using polyethylene glycol (PEG) 3350 with electrolyte solution for disimpaction in hospitalized children.

METHODS

We retrospectively studied 28 children having functional constipation who received inpatient treatment between 2008 and 2016. The amount of oral PEG 3350 electrolyte solution administered was 50-70 mL/kg/d (PEG 3350, 3-4.1 g/kg/d), and an enema solution was administered 1-2 times a day as a single dose of 15-25 mL/kg (PEG 3350, 0.975-1.625 g/kg/d). A colon transit time (CTT) test based on the Metcalf protocol was performed in some patients.

RESULTS

Administration of oral and enema doses of PEG 3350 electrolyte solution showed 2.1±0.3 times and 2.9±0.4 times, respectively. After disimpaction, the frequency of defecation increased from 2.2±0.3 per week to once a day (1.1±0.1 per day). The number of patients who complained of abdominal pain was reduced from 15 (53.6%) to 4 (14.3%). Before hospitalization, nine patients underwent a CTT test, and 5 of 9 patients (55.6%) were classified as belonging to a group showing abnormalities. And in some patients, mild adverse effects were noted. We examined electrolytes and osmolality before and after disimpaction in 16 of 28 patients, and no abnormalities were noted.

CONCLUSION

In terms of therapeutic efficacy and safety, combined oral and enema therapy using high-dose PEG 3350 with electrolytes is considered superior to conventional oral monotherapy or combined oral and enema therapy on an outpatient basis.

Correlation between Colon Transit Time Test Value and Initial Maintenance Dose of Laxative in Children with Chronic Functional Constipation

PURPOSE

To evaluate the correlation between colon transit time (CTT) test value and initial maintenance dose of polyethylene glycol (PEG) 4000 or lactulose.

METHODS

Of 415 children with chronic functional constipation, 190 were enrolled based on exclusion criteria using the CTT test, defecation diary, and clinical chart. The CTT test was performed with prior disimpaction. The laxative dose for maintenance was determined on the basis of the defecation diary and clinical chart. The Shapiro-Wilk test and Pearson's and Spearman's correlations were used for statistical analysis.

RESULTS

The overall group median value and interquartile range of the CTT test was 43.8 (31.8) hours. The average PEG 4000 dose for maintenance in the overall group was 0.68±0.18 g/kg/d; according to age, the dose was 0.73±0.16 g/kg/d (<8 years), 0.53±0.12 g/kg/d (8 to <12 years), and 0.36±0.05 g/kg/d (12 to 15 years). The dose of lactulose was 1.99±0.43 mL/kg/d (<8 years) or 1.26±0.25 mL/kg/d (8 to <12 years). There was no significant correlation between CTT test value and initial dose of laxative, irrespective of the subgroup (encopresis, abnormal CTT test subtype) for either laxative. Even in the largest group (overall, n=109, younger than 8 years and on PEG 4000), the correlation was weak (Pearson's correlation coefficient [R]=0.268, p=0.005). Within the abnormal transit group, subgroup (n=73, younger than 8 years and on PEG 4000) correlation was weak (R=0.267, p=0.022).

CONCLUSION

CTT test value cannot predict the initial maintenance dose of PEG 4000 or lactulose with linear correlation.