Pediatric urology is the diagnosis and treatment of congenital (present at birth) and acquired urological conditions and diseases in children. Pediatric urologists treat conditions of the male reproductive tract (e.g., undescended testicle) and the male and female urinary tracts (e.g., urinary tract infection).
The urinary tract consists of the kidneys (organs that filter the blood and form urine), the ureters (tubes that carry urine from the kidneys), the bladder (organ that stores urine), and the urethra (tube that carries urine from the bladder and removes it from the body).
The most common condition treated by pediatric urologists is urinary tract infection (UTI). Other conditions include the following:
Pediatric Urological Examination
Most children under the care of a pediatric urologist are school-aged and younger. UTIs (e.g., cystitis) are most common in young girls and pediatric urological conditions are usually congenital and treated at a young age. Conditions such as vesicoureteral reflux and antenatal hydronephrosis are frequently diagnosed during prenatal ultrasound and hypospadias is usually diagnosed during infancy.
The pediatric urological examination includes a medical history and a comprehensive physical examination. A history of symptoms, illnesses, injuries, medications, prenatal ultrasound, and family history are documented. A urinary catheter may be inserted into the bladder through the urethra to withdraw urine. Diagnostic tests include the following:
Antenatal (before birth) hydronephrosis is a condition in which the outflow of urine from the kidney is obstructed, resulting in fluid-filled enlargement. The condition is usually detected by ultrasound, as early as the first trimester of pregnancy.
Antenatal hydronephrosis can be mild, moderate, or severe and it requires monitoring before birth and during infancy and childhood. Occasionally, the kidney appears dilated (enlarged) during antenatal ultrasound yet functions normally after birth.
Most (99%) adrenal tumors are benign (i.e., noncancerous) adrenal cortical adenomas and do not require treatment. These tumors usually do not cause symptoms, are small, and are found incidentally during diagnostic imaging.
The most common type of adrenal cancer develops in the adrenal cortex and is called adrenocortical carcinoma. Functioning adrenocortical carcinomas may produce symptoms related to increased hormone production.
Nonfunctioning tumors may cause pain from pressure on abdominal organs and a palpable (able to be felt with the fingers) mass in the abdomen.
Cancers that develop in the adrenal medulla include neuroblastoma (originates in undeveloped nerve cells) and pheochromocytoma (originates in cells that produce epinephrine and norephinephrine). Neuroblastoma usually occurs in infants and children and pheochromocytoma more commonly occurs in people who are in their 30s and 40s.
Other types of cancer (e.g., breast, lung) may spread (metastasize) to the adrenal glands.
Hypospadias is a congenital (present at birth) condition in which the opening of the urethra (tube that carries urine and, in males, semen from the body) is located below the normal location. This is caused by incomplete development of the urethra in utero between 8 and 20 weeks of gestation.
Various degrees of hypospadias result in an opening located anywhere along the length of the urethra. Degrees of hypospadias are classified according to location, including anterior (50% of cases), middle (20% of cases), and posterior (30% of cases). Hypospadias may also cause a curvature of the penis (chordee). Chordee is sometimes evident only with an erection. Severe chordee may result in the inability to perform sexual intercourse.
Without surgical correction, severe hypospadias may result in the inability to urinate standing and infertility.
Incidence and Prevalence
Hypospadias occurs in approximately 1 in 300 males and 1 in 500,000 females in the United States. Worldwide incidence is rising, partially due to an increase in the number of minor cases being reported. The condition is more common in infants of Jewish and Italian descent.
Risk Factors and Causes
The cause of hypospadias is unknown but may include genetic, endocrinological, and environmental factors. Genetic factors are suggested by an increase in the condition in twins compared to a single birth. Human chorionic gonadotropin (hCG) is a hormone produced in early pregnancy that stimulates the production of estrogen and progesterone. In the case of twins, the production of hCG may not be sufficient to prevent incomplete urethral development. There is also a 20% chance that an infant born with hypospadias has a family member with the condition.
Endocrinological factors include low levels of androgens (e.g., testosterone, androsterone) and the infant’s cells’ inability to use these substances effectively may also result in hypospadias. Androgens are substances that stimulate the development of male characteristics.
Maternal exposure to increased levels of progesterone, common during in vitro fertilization (IVF), increases the risk for hypospadias in the infant.
Environmental exposure to estrogen during urethral development may also be a risk factor. Exposure can result when the mother ingests pesticides on fruits and vegetables and milk from pregnant cows.
Signs and Symptoms
Hypospadias results in a urethral opening located below the tip of the glans penis (bulbous end of the penis). This opening may be located on the glans, along the shaft of the penis, at the scrotum (pouch that contains the testicles), or in the perineum (area between the scrotum and the anus). The farther the opening is from the tip of the glans, the more likely chordee (curvature in the penis) is present.
Mild hypospadias results in a downward spray of the urine stream.
Common complications of severe hypospadias are undescended testicles and inguinal hernias (i.e., located in the groin). Other complications include upper urinary tract anomalies and vesicoureteral reflux (backflow of urine from the ureter to the bladder).
Hypospadias is sometimes diagnosed by prenatal ultrasound, but it usually occurs in males at birth. Upon examination, the foreskin is usually incomplete and the misplaced urethral opening is located. Mild hypospadias may not be diagnosed unless circumcision (removal of the foreskin) is performed. Diagnosis of hypospadias in females requires more thorough physical examination.
Cases of hypospadias in which the urethral opening is near the tip of the glans do not require treatment if the urine stream is straight and there is no chordee. Moderate or severe hypospadias requires surgery to achieve the following:
Surgery is usually performed under general anesthesia when the child is between the ages of 6 and 18 months. Techniques vary considerably from case to case and may involve stages. Before surgery, testosterone injections or creams may be used to increase penis size and antibiotics are administered to lower the risk for infection. A catheter is inserted into the bladder to drain urine.
First, the anatomy is thoroughly assessed. The penile skin is retracted and any curvature is corrected by removing the hardened tissue or plicating (pinching) tissue to offset the curvature. Then, the urethra is extended using local tissue from the foreskin and the opening is repositioned at the tip of the glans. If an adequate amount of tissue is not available, tissue from inside the mouth may be used. Finally, the penile skin is replaced and sutured.
Local swelling and minor bleeding are common following surgery to repair hypospadias and usually are not severe. Antibiotics are continued after the procedure and infection is rare. Complications include adverse reactions to anesthesia and excessive bleeding that may require additional surgery.
Long-term complications that may require additional surgery include the following:
The prognosis for hypospadias depends on the severity of the condition. Surgical correction for moderate or severe conditions is becoming increasingly successful. Surgical advancements (e.g., tissue glue, laser procedures, urethral substitutes) and antenatal (before birth) intervention that may improve the prognosis are being developed.
Hypospadias cannot be prevented.
Nocturnal enuresis is a condition in which a person who has bladder control while awake urinates while asleep. The condition is commonly called bed-wetting and it often has a psychological impact on children and their families. Children with the condition often have low self-esteem and their interpersonal relationships, quality of life, and school performance are affected.
Children achieve bladder control (continence) at different ages and usually achieve daytime continence before nighttime dryness. Most children are continent by the age of 4 or 5. Nocturnal enuresis is common and usually does not require treatment in children of preschool age who have achieved continence during the day.
Nocturnal enuresis is classified as primary (PNE) or secondary(SNE). In primary nocturnal enuresis, the child has never been consistently dry at night. If the child has experienced at least 6 months of dryness at night and then begins bed-wetting, the condition is referred to as secondary nocturnal enuresis. Psychological issues and acquired medical conditions cause the development of SNE.
Incidence and Prevalence
Nocturnal enuresis is more common in males and prevalence of the condition gradually declines during childhood. Approximately 23% of 5-year olds, 20% of 7-year olds, 4% of 10-year olds, and 1–2% of those aged 18 and older experience bed-wetting. Secondary nocturnal enuresis accounts for approximately 25% of cases.
Risk Factors and Causes
There are a number of causes for nocturnal enuresis. Primary nocturnal enuresis is often caused by a chromosomal abnormality and there is a strong genetic link associated with the condition. Children whose parents or siblings experienced bed-wetting are at increased risk. If one parent had the condition, the risk is approximately 45% and if both parents had the condition, the risk is approximately 75%.
Other causes of PNE include the following:
Secondary nocturnal enuresis may be caused by psychological issues (e.g., death in the family, sexual abuse, extreme bullying) and is often associated with stress. It may also result from an acquired condition such as diabetes, hyperthyroidism (overproduction of hormone by the thyroid gland), seizure disorder (e.g., epilepsy), and obstructive sleep apnea (OSA).
Signs and Symptoms
Nocturnal enuresis causes regular involuntary bed-wetting during sleep.
Diagnosis of nocturnal enuresis is made when involuntary urination regularly occurs during sleep in a person who is continent while awake. Determining the cause for the condition requires a detailed medical history and a comprehensive physical examination.
Medical history includes the following:
Physical examination includes the following:
Various diagnostic tests may also be performed to determine the cause of bed-wetting. These tests are reserved for patients in whom physical abnormality or obstruction are suspected. Urinalysis is performed to detect cystitis, UTI, urethral obstruction, diabetes, and other possible physical causes. Imaging or other tests used to detect abnormalities may include the following:
Other urodynamic studies (measures the storage and rate of movement of urine from the bladder) and uroflowmetry (measures urine flow) may also be performed.
The goals of treatment are to reduce the social and psychological impact of the condition and to eliminate the underlying cause. Treatments include the following:
It is important to manage nocturnal enuresis in a way that reduces the child’s embarrassment and the anxiety within the family. Family members who have outgrown the condition can share their experience with the child to reduce feelings of isolation. Parents should use patience and caring while waiting for the child to outgrow bed-wetting. Behavior modifications often improve nighttime dryness within 1 month.
Positive reinforcement (e.g., keeping a chart with gold stars awarded for dry nights) is sometimes beneficial, as is periodically waking the child at night to use the bathroom. An alarm clock set to go off a few hours after the child goes to bed can be used to wake the child or the parent can wake the child before retiring for the night.
Restricting the intake of fluids late in the day and encouraging voiding at regular intervals throughout the day may also be helpful. The child should be encouraged to use the bathroom every 1–2 hours during the day and immediately before bed. The restriction of fluids should not be demanded in a way that suggests punishment and should be implemented carefully in children who are physically active and in warm weather to reduce the risk for dehydration.
Alarm therapy has a success rate of approximately 70%, works best in older children who are well motivated, and requires commitment from all household members who may be awakened by the alarm. It takes from 2 weeks to several months to produce improvement, and if the child is not dry after 3 consecutive months of use, therapy should be discontinued until the child is older.
The alarm is positioned to sense wetness promptly and although most children sleep through the alarm, they stop voiding when it sounds. A parent then helps the child to the bathroom to finish voiding; changes wet sheets and pajamas; resets the alarm; and takes the child back to bed. Some children who achieve success with this type of therapy are able to sleep through the night without voiding, but others may continue to get up during the night to use the bathroom (nocturia).
Drug therapy usually is reserved for children who have had no success with nonpharmacological treatments. Medications used to treat nocturnal enuresis include the following:
Desmopressin (DDAVP®) is an antidiuretic that is used to treat primary nocturnal enuresis. DDAVP® is available in a nasal spray (10–40 mcg, at bedtime) or oral form (0.2-0.6mg, at bedtime) and is up to 55% effective. It may also be combined with alarm therapy. Side effects of the nasal spray include nasal discomfort, nosebleed, abdominal pain, and headache. It is important to reduce fluid intake when taking DDAVP. If fluids are not restricted, water intoxication may occur. This condition requires immediate medical attention. Symptoms of water intoxication include headache, nausea, vomiting, and seizure.
Ditropan® and Levsin® are anticholinergic medications that reduce muscle contractions in the bladder. The usual dose is 2.5–5 mg taken at bedtime. Side effects include blurred vision, constipation, dizziness, dry mouth, facial flushing, and fluctuations in mood.
Tofranil® may be prescribed in doses of 25 mg in children 6 to 8 years old and 50–75 mg in older children, taken 1 to 2 hours before bed. This antidepressant effectively treats primary nocturnal enuresis without organic causes in as many as 40% of cases when used as a temporary adjuvant therapy. Side effects include the following:
Overdose can be fatal and the World Health Organization (WHO) does not recommend using this drug for nocturnal enuresis.
Oral antibiotics (e.g., Bactrim®, amoxicillan, Macrobid®, Levaquin®) are used to treat UTIs that cause bed-wetting.
Structural abnormalities in the urinary system (e.g., ectopic ureter) and other conditions, such as obstructive sleep apnea and heart block, may require surgery. Surgery to correct these conditions often eliminates nocturnal enuresis.
The prognosis for children who experience nocturnal enuresis depends on the cause. Almost all children outgrow bed-wetting, even without treatment.
Undescended testicle, also called cryptorchidism, is a common condition in which one of the testes (testicle, male reproductive gland) is located outside of the scrotum. During the eighth month of gestation, the testes migrate from the abdomen, through the groin, and into the scrotum (pouch that contains the testes). An undescended testicle is located in the abdominal cavity, in the inguinal canal (passageway in the groin), or in an ectopic location (e.g., superficial pouch in the groin, perineum, upper thigh). This condition is usually congenital (present at birth) and is associated with sterility and an increased risk for testicular cancer if not corrected.
Incidence and Prevalence
Undescended testicle occurs in approximately 30% of premature males and 3% of full term male infants. In 80% of cases, the undescended testicle migrates into the correct position without intervention during the first year. The condition occurs in both testicles in about 10% of cases.
Risk Factors and Causes
The cause of undescended testicle is unknown. Having a father or brother who had the condition increases the risk. Other risk factors include the following:
Signs and Symptoms
An undescended testicle is not located within the scrotum. The condition may be associated with other abnormalities of the genitourinary system (e.g., hypospadius).
Diagnosis of this condition is made through physical examination at birth to locate the testis. It is sometimes diagnosed by prenatal ultrasound. If one testicle is undescended, the scrotum appears unbalanced. If the undescended testis is palpable (able to be felt) it may not have descended fully, may have descended into a location other than the scrotum (ectopic), or may move in and out of the scrotum through muscle contraction (retractile).
If the testis is not palpable, it may be located within the abdomen or may be absent (occurs in 5% of cases). A congenitally absent testicle may result from an abnormality in testicular blood vessels or testicular torsion in utero. This condition is diagnosed using a blood test to determine the level of gonadotropin (hormone that stimulates development of the testes).
Treatment for undescended testicle may include manipulation into the scrotum (in cases of retractile testes), hormone therapy, and surgery. Treatment is not recommended until after the age of 1 year, because in most cases, the testis descends without intervention during this time. The goals of treatment include the following:
Hormonal therapy with human chlorionic gonadotropin hormone (hCG) is used with some success when the testis is not located within the abdomen. Hormone injections are administered twice per week, for 5 weeks. Side effects include increased scrotal folds or creases, increased skin pigmentation, penile growth, and pubic hair. These effects regress when treatment is discontinued. This therapy may be combined with gonadotropin-releasing hormone (GnRH) therapy, but has not been approved in the United States.
Surgery for an undescended testicle is called orchidopexy or orchiopexy. If the testicle is located outside of the abdomen (i.e., in the groin), the procedure is performed under general anesthesia and the patient is usually discharged the same day.
In this procedure, which takes approximately 90 minutes, the testicle is located, removed through a small incision, and placed into the scrotum through another small incision. The testicle may be sutured into place. Bed rest is recommended for 2 or 3 days following orchidopexy and strenuous activity should be avoided for approximately 1 month. Success rates for this procedure are generally good and fertility is usually achieved.
An undescended testicle that remains in the abdomen is located in an exploratory laparoscopy. In this procedure, a small incision is made near the navel and a laparoscope (telescope-like instrument that consists of a tiny camera and a light) is inserted to allow the physician to see inside the abdomen and locate the testicle. The physician then removes the testicle (if it is malformed) or performs orchidopexy. Success rates for this procedure are lower than if the testicle is located outside of the abdomen.
Complications from orchidopexy include adverse reactions to anesthesia, bleeding, and infection.
Undescended testicles usually descend into the scrotum without intervention within the first year of life. The prognosis for fertility in these cases, as well as those that are surgically corrected, is good.
Overview The kidney (organ that produces urine) and the ureter (tube that carries urine from the kidney to the bladder) join at the ureteropelvic junction (UPJ). Narrowing (stricture) at this junction reduces the flow of urine from the kidney and can result in enlargement of the kidney caused by the backup of urine into the renal pelvis (hydronephrosis) and kidney damage. UPJ obstruction can be severe, minimal, or intermittent and is often diagnosed during prenatal ultrasound. It is the most common cause of hydronephrosis in utero and in newborns.
Incidence and Prevalence
Approximately 1% of prenatal ultrasounds detect hydronephrosis in the fetus. In 50% of these cases, UPJ obstruction causes the condition. UPJ obstruction is more common in males and affects the left kidney more often than the right. About 20–30% of cases occur in both kidneys (bilaterally).
Congenital abnormalities are the most common cause of UPJ obstruction in young children. The condition often results from an abnormality in the muscles that surround the UPJ. It may also be caused by an abnormality in the structure or position of the ureter, kidney, and renal blood vessels. In older children, UPJ obstruction may be caused by the following:
Signs and Symptoms
Symptoms of UPJ obstruction include the following:
UPJ obstruction that causes hydronephrosis is usually diagnosed by prenatal ultrasound. Neonatal patients suspected to have this condition are evaluated for the obstruction using renal ultrasound. Other imaging tests may also be required.
Other diagnostic tests used to evaluate kidney function and determine the severity of the blockage include the following:
In diuretic renal scan, a small amount of radioactive substance is injected into a vein and kidney function is assessed using scanned images of the organ as it removes the substance from the blood.
Newborns with UPJ obstruction and hydronephrosis are placed on antibiotics to prevent infection and are monitored with renal ultrasound every 3 to 6 months. If UPJ obstruction causes a significant reduction in renal function, a surgical procedure called pyeloplasty is performed to remove the obstruction, improve urine flow, and reduce the risk for kidney damage. Pyeloplasty involves removing the blockage and reattaching the ureter to the renal pelvis. A temporary stent (device that holds the ureter open) may be inserted to drain the kidney.
Complications include the following:
Patients require follow-up care for several years following pyeloplasty. Tests to evaluate kidney function are performed regularly (6 months to 1 year).
The success rate for patients who undergo pyeloplasty is higher than 95%.
Ureteropelvic junction obstruction cannot be prevented.
Vesicoureteral reflux (VUR) is the backup of urine from the bladder (organ that stores urine) into the ureter (tube that carries urine from the kidney to the bladder) during urination. VUR may result in urine reflux into the renal pelvis, (glossary link) causing distention (hydronephrosis) and kidney damage. In children, this condition is usually caused by congenital (present at birth) abnormalities and is often diagnosed during prenatal ultrasound.
There are two types of VUR: primary and secondary. Primary reflux is caused by a congenital (present at birth) abnormality, and secondary reflux is caused by a urinary tract infection (UTI) or an obstruction in the urinary tract.
Reflux is graded according to its severity:
Incidence and Prevalence
VUR is diagnosed in 17–37% of prenatal ultrasounds. The condition is more prevalent in females and in children who have red hair. One-third of UTIs in children are caused by vesicoureteral reflux.
Causes and Risk Factors
Undetermined genetic risk factors may affect the development of VUR. About 34% of patients who have the condition have siblings who are also affected. Siblings of patients with VUR are routinely tested for the condition, even when symptoms are not present.
The most common cause for primary reflux in children is an abnormality in the section of the ureter that enters the bladder (called the intravesical ureter). The intravesical ureter may not be long enough to enable the ureter to close sufficiently to prevent urine reflux, or the ureter may be inserted abnormally into the bladder. This condition often resolves as the child grows and the ureter lengthens.
Other causes of primary reflux include abnormalities in detrusor muscle tissue of the bladder, abnormalities in the location of the urethral opening (e.g., hypospadias), and abnormalities in the shape of the urethral opening.
Secondary reflux is often caused by urinary tract infection (e.g., cystitis) that results in inflammation and swelling of the ureter. UTI may cause vesicoureteral reflux or vesicoureteral reflux may promote the growth of bacteria in the urinary tract, causing UTI. Secondary reflux may also be caused by urinary tract abnormalities (e.g., narrowing, or stricture, of the ureter; duplicated ureters; ureterocele) and obstructions (e.g., UPJ obstruction, stones, tumor).
Signs and Symptoms
The most common symptom of VUR is urinary tract infection (UTI). Other symptoms might include the following:
Untreated VUR provides access for bacteria to enter the kidneys and may result in kidney infection (pyelonephritis), kidney damage, and progressive renal failure.
VUR is commonly diagnosed during infancy or childhood as a result of a urinary tract infection (UTI). UTI is diagnosed using urinalysis and urine culture. VUR that causes hydronephrosis (collection of urine in the renal pelvis) is often diagnosed during prenatal ultrasound.
A cystogram (also called cystourethrogram) and a voiding cystourethrogram (VCUG) are performed to determine if an abnormality in the urinary tract is causing reflux. In these procedures, a contrast dye is instilled into the bladder through a catheter and a series of x-rays are taken. Other diagnostic tests used to diagnose VUR include the following:
Medication Treatment for grades I – III VUR includes daily low-dose antibiotics (e.g., trimethoprim-sulphamethoxazole, amoxicillin) until the reflux resolves or until the child is at least 5 years old. These cases require regular monitoring by a pediatric urologist to diagnose UTI and prevent the condition from worsening.
Secondary reflux that does not resolve with antibiotic treatment, or that results in UTI despite antibiotic therapy (called breakthrough infections), and primary reflux that is severe (grades IV and V) require surgery to prevent permanent kidney damage.