Bedwetting isn’t always due to problems with the bladder, according to new research by Wake Forest Baptist Medical Center. Constipation is often the culprit; and if it isn’t diagnosed, children and their parents must endure an unnecessarily long, costly and difficult quest to cure nighttime wetting.
Reporting online in the journal Urology, researchers found that 30 children and adolescents who sought treatment for bedwetting all had large amounts of stool in their rectums, despite the majority having normal bowel habits. After treatment with laxative therapy, 25 of the children (83 percent) were cured of bedwetting within three months.
“Having too much stool in the rectum reduces bladder capacity,” said lead author Steve J. Hodges, M.D., assistant professor of urology at Wake Forest Baptist. “Our study showed that a large percentage of these children were cured of nighttime wetting after laxative therapy. Parents try all sorts of things to treat bedwetting - from alarms to restricting liquids. In many children, the reason they don’t work is that constipation is the problem.”
Hodges said the link between bedwetting and excess stool in the rectum, which is the lower five to six inches of the intestine, was first reported in 1986. However, he said the finding did not lead to a dramatic change in clinical practice, perhaps because the definition of constipation is not standardized or uniformly understood by all physicians and lay people.
“The definition for constipation is confusing and children and their parents often aren’t aware the child is constipated,” said Hodges. “In our study, X-rays revealed that all the children had excess stool in their rectums that could interfere with normal bladder function. However, only three of the children described bowel habits consistent with constipation.”
Hodges explained that guidelines of the International Children’s Continence Society recommend asking children and their parents if the child’s bowel movements occur irregularly (less often than every other day) and if the stool consistency is hard.
“These questions focus on functional constipation and cannot help identify children with rectums that are enlarged and interfering with bladder capacity,” said Hodges. “The kind of constipation associated with bedwetting occurs when children put off going to the bathroom. This causes stool to back up and their bowels to never be fully emptied. We believe that treating this condition can cure bedwetting.”
Children in the study ranged from 5 to 15 years old. The constipated children were treated with an initial bowel cleanout using polyethylene glycol (Miralax®), which softens the stools by causing them to retain water. In children whose rectums remained enlarged after this therapy, enemas or stimulant laxatives were used.
While bedwetting can be a symptom of an underlying disease, the large majority of children who wet the bed have no underlying disease. In fact, a true organic cause is identified in only about 1% of children who wet the bed. However, this does not mean that the child who wets the bed can control it or is doing it on purpose. Children who wet the bed are not lazy, willful, or disobedient.
There are two types of bedwetting: primary and secondary. Primary bedwetting refers to bedwetting that has been ongoing since early childhood without a break. A child with primary bedwetting has never been dry at night for any significant length of time. Secondary bedwetting is bedwetting that starts again after the child has been dry at night for a significant period of time (at least six months).
In general, primary bedwetting probably indicates immaturity of the nervous system. A bedwetting child does not recognize the sensation of the full bladder during sleep and thus does not awaken during sleep to urinate into the toilet.
The cause is likely due to one or a combination of the following:
- The child cannot yet hold urine for the entire night.
- The child does not waken when his or her bladder is full.
- The child produces a large amount of urine during the evening and night hours.
- The child has poor daytime toilet habits. Many children habitually ignore the urge to urinate and put off urinating as long as they possibly can. Parents are familiar with the “potty dance” characterized by leg crossing, face straining, squirming, squatting, and groin holding that children use to hold back urine.
Secondary bedwetting can be a sign of an underlying medical or emotional problem. The child with secondary bedwetting is much more likely to have other symptoms, such as daytime wetting. Common causes of secondary bedwetting include the following:
- Urinary tract infection: The resulting bladder irritation can cause lower abdominal pain or irritation with urination (dysuria), a stronger urge to urinate (urgency), and frequent urination (frequency). Urinary tract infection in children may indicate another problem, such as an anatomical abnormality.
- Diabetes: People with type I diabetes have a high level of sugar (glucose) in the their blood. The body increases urine output as a consequence of excessive blood glucose levels. Having to urinate frequently is a common symptom of diabetes.
- Structural or anatomical abnormality: An abnormality in the organs, muscles, or nerves involved in urination can cause incontinence or other urinary problems that could show up as bedwetting.
- Neurological problems: Abnormalities in the nervous system, or injury or disease of the nervous system, can upset the delicate neurological balance that controls urination.
- Emotional problems: A stressful home life, as in a home where the parents are in conflict, sometimes causes children to wet the bed. Major changes, such as starting school, a new baby, or moving to a new home, are other stresses that can also cause bedwetting. Children who are being physically or sexually abused sometimes begin bedwetting.
- Sleep patterns: Obstructive sleep apnea (characterized by excessively loud snoring and/or choking while asleep) can be associated with enuresis.
- Pinworm infection: characterized by intense itching of the anal and/or genital area.
- Excessive fluid intake.
Hodges cautioned that any medical therapy for bedwetting should be overseen by a physician.
The study used abdominal X-rays to identify the children with excess stool in their rectums. Hodges and radiologists at Wake Forest Baptist developed a special diagnostic method that involves measuring rectal size on the X-ray. He said rectal ultrasound could also be used for diagnosis.
“The importance of diagnosing this condition cannot be overstated,” Hodges said. “When it is missed, children may be subjected to unnecessary surgery and the side effects of medications. We challenge physicians considering medications or surgery as a treatment for bedwetting to obtain an X-ray or ultrasound first.”
The study involved reviewing the charts of 30 consecutive patients treated for bedwetting. The authors cautioned that some cases may have improved on their own over time. They said a more accurate measure of the treatment’s success would be to randomly assign constipated children to laxative therapy or an inactive therapy, an approach that would identify true response from cases that would resolve over time.
Hodges’ co-author on the research is Evelyn Y. Anthony, MD, a radiologist at Wake Forest Baptist.
Hodges has written a book for consumers that covers this and other pediatric urology issues. “It’s No Accident: Breakthrough Solutions To Your Child’s Wetting, Constipation, UTIs, and Other Potty Problems,” published by Globe Pequot Press, will be released in early February.
Wake Forest Baptist Medical Center is a fully integrated academic medical center located in Winston-Salem, North Carolina. The institution comprises the medical education and research components of Wake Forest School of Medicine, the integrated clinical structure and consumer brand Wake Forest Baptist Health, which includes North Carolina Baptist Hospital and Brenner Children’s Hospital, the commercialization of research discoveries through the Piedmont Triad Research Park, as well a network of affiliated community based hospitals, physician practices, outpatient services and other medical facilities. Wake Forest School of Medicine is ranked among the nation’s best medicine schools and is a leading national research center in fields such as regenerative medicine, cancer, neuroscience, aging, addiction and public health sciences. Wake Forest Baptist’s clinical programs are consistently ranked as among the best in the country by U.S.News & World Report.
Wake Forest Baptist Medical Center