The urinary system consists of the kidneys, ureters, bladder and urethra. After the kidneys produce urine, the urine travels through the ureters into the bladder. The bladder holds the urine until elimination occurs. Children develop bladder control as they age, but problems with muscle control or nerve function can cause pediatric bladder control problems.
Bedwetting
Bedwetting refers to involuntary urination, which is not a disease but a symptom of a physical or psychological condition that affects bladder control. Doctors refer to daytime bedwetting as diurnal enuresis. This type of bedwetting occurs due to bladder weaknesses or abnormalities, urinary tract infections and diabetes. Dr. Robert Needleman, a contributor to the Dr. Spock website, reports that daytime bedwetting also has psychological causes. These causes include stress, jealousy over the arrival of a new baby and enrollment in a new school. Medical professionals refer to nighttime bedwetting as nocturnal enuresis. This type of bedwetting sometimes causes stress for children and their families, especially if a child worries about wetting the bed at a sleepover. This type of bedwetting affects 15 to 25 percent of 5-year-old children, according to the American Academy of Family Physicians. This condition occurs more commonly in boys than girls. The AAFP reports that, while urodynamic testing reveals normal real bladder capacity in children who experience nighttime bedwetting, these children may have reduced functional bladder capacity. Functional bladder capacity refers to the volume at which the nerves and muscles of the bladder trigger urination. Nocturnal increases in a hormone known as arginine vasopressin may also cause bedwetting at night. Other potential causes of nighttime bedwetting include a family history of bedwetting and the presence of sleep disorders.
Overactive Bladder
The bladder consists of strong muscles and nerves. The muscles control the release of urine, while the nerves work with the brain to trigger the act of urination. In children with overactive bladder, the bladder muscle contracts strongly without any prior warning. This contraction makes it difficult for the muscles around the urethra--the tube that empties urine from the body--to control the release of urine.
Constipation
Although some people think constipation only affects the digestive system, the National Kidney and Urological Diseases Information Clearinghouse indicates that constipation can cause a loss of bladder control. When hardened stool puts pressure on the bladder muscle wall, it makes it more difficult for the bladder to prevent the release of urine.
Neurogenic Bladder
Neurogenic bladder refers to a problem caused by nerve damage. In children without neurogenic bladder, the nerves send messages back and forth between the bladder muscles and the brain. Nerve damage interrupts the transmission of these signals, which causes the bladder muscles to tighten and relax at the wrong times. Some causes of this condition include spinal cord injuries, brain tumors, stroke and multiple sclerosis. Neurogenic bladder causes frequent urination of small amounts, loss of bladder control, problems emptying the urine out of the bladder, urine leakage, urinary retention and an inability to recognize when the bladder is full.
