Correlation between Colon Transit Time Test Value and Initial Maintenance Dose of Laxative in 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.

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.

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.