ABU Pediatric Urology key terms

Retrograde flow of urine from the bladder into the ureter and sometimes kidney, graded I to V by the degree of dilatation and tortuosity seen on voiding cystourethrography. It predisposes to pyelonephritis and renal scarring, especially when combined with infected urine or bladder dysfunction.

Fluoroscopic study in which contrast is instilled into the bladder through a catheter and images are taken during filling and voiding. It is the reference standard for detecting and grading vesicoureteral reflux and for assessing urethral anatomy such as posterior urethral valves.

Dilatation of the renal collecting system, most often detected on prenatal or postnatal ultrasound. It may be physiologic and transient or may signal obstruction, reflux, or a duplicated system, and severity is graded by the degree of pelvic and calyceal dilatation.

Blockage of urine flow where the renal pelvis joins the ureter, producing hydronephrosis with preserved ureteral caliber. It may be congenital or acquired and is evaluated with diuretic renography to determine whether drainage is obstructed and whether surgery is needed.

Congenital obstructing membranes in the posterior urethra of boys that block bladder emptying and can cause bilateral hydronephrosis, bladder hypertrophy, and renal injury. Presentation ranges from prenatal oligohydramnios to urinary tract infection or voiding difficulty in infancy.

Persistent bladder dysfunction and upper tract deterioration that continues after successful relief of posterior urethral valve obstruction, driven by a thick-walled, poorly compliant bladder. It requires long-term surveillance of bladder pressures and renal function.

Dilatation of the fetal renal collecting system found on obstetric ultrasound, defined by anteroposterior renal pelvic diameter thresholds that vary with gestational age. It prompts postnatal imaging to distinguish transient dilatation from obstruction or reflux.

Abnormally low amniotic fluid volume, which in fetal uropathy reflects reduced fetal urine output. Prolonged severe oligohydramnios can cause pulmonary hypoplasia and limb compression, and it is a key prognostic marker in obstructive and dysplastic renal disease.

Congenital renal malformation in which the kidney is replaced by noncommunicating cysts with dysplastic parenchyma and little or no function. Most cases regress over time and are managed with observation, though associated contralateral anomalies require evaluation.

Irreversible loss of functioning renal cortex, typically appearing as a focal cortical defect over a calyx after febrile urinary tract infection in a kidney with reflux or dysplasia. Extensive scarring can lead to hypertension and reduced renal function.

Nuclear medicine cortical imaging study that shows functioning renal tissue and focal cortical defects. It is used to detect renal scarring after infection and to assess differential renal function when surgery is being considered.

Nuclear medicine study combining a tubular tracer with a diuretic to assess renal function and drainage. Persistently poor washout after diuresis suggests obstruction, and the study helps decide whether hydronephrosis requires surgical correction.

Surgical reconstruction of the ureteropelvic junction, usually by excising the narrowed segment and reanastomosing the ureter to the renal pelvis. It is the standard treatment for significant ureteropelvic junction obstruction and may be performed open, laparoscopic, or robotically.

Urinary tract infection accompanied by fever, indicating probable renal involvement rather than isolated bladder infection. In children it warrants prompt treatment and imaging evaluation because repeated episodes in susceptible kidneys can produce cortical scarring.

Continuous low-dose antibiotic given to prevent recurrent urinary tract infections, most often in children with vesicoureteral reflux or significant bladder dysfunction. Benefits must be weighed against bacterial resistance and are greatest in high-grade reflux and recurrent febrile infection.

Cystic dilatation of the distal ureteral segment that balloons into the bladder. It can obstruct the affected ureter and sometimes the bladder outlet, and is often associated with a duplicated collecting system in which the upper pole ureter is affected.

Congenital anomaly in which a kidney drains through two ureters, either joining before the bladder or inserting separately. The upper pole ureter tends to insert ectopically and obstruct, while the lower pole ureter tends to reflux.

Ureter that inserts distal to the normal bladder trigone, such as into the bladder neck, urethra, or vagina. In girls it classically causes continuous urinary incontinence despite otherwise normal voiding, and the draining renal segment is often dysplastic.

Congenital anomaly in which the urethral meatus opens on the ventral penis proximal to the glans, often with ventral curvature and a deficient prepuce. Repair is typically performed in infancy, and circumcision should be avoided before reconstruction because the foreskin may be needed.

Ventral curvature of the penis, usually congenital and associated with hypospadias but sometimes occurring with an otherwise normal meatus. Significant curvature is corrected during hypospadias repair so the penis is straight for sexual function.

Failure of one or both testes to descend into the scrotum, whether undescended, ectopic, or absent. Treatment by orchidopexy is recommended in the first year of life to preserve fertility potential and to allow surveillance for malignancy.

Surgical fixation of an undescended or torsed testis into the scrotum. In cryptorchidism it is performed electively in infancy, while in torsion it is done emergently along with fixation of the opposite testis.

Twisting of the spermatic cord that cuts off blood supply to the testis, causing acute scrotal pain and tenderness. It is a surgical emergency because viability falls rapidly with time, and the contralateral testis is fixed at the same operation.

Congenital conditions in which chromosomal, gonadal, or anatomic sex is atypical, such as androgen insensitivity or congenital adrenal hyperplasia. Evaluation requires karyotype, hormonal testing, and imaging, with management decided by a multidisciplinary team and family involvement.

Inherited enzyme deficiency, most often 21-hydroxylase, that causes cortisol deficiency with excess adrenal androgens. In newborn girls it produces virilized ambiguous genitalia and can cause life-threatening salt-wasting crises, so it is both an endocrine and a urologic emergency.

Distension of the vagina with fluid, often due to distal vaginal obstruction such as an imperforate hymen or cloacal anomaly. It can present as a pelvic mass in a newborn girl and may compress the bladder and cause urinary retention.

Incomplete closure or malformation of the spinal column and cord, including myelomeningocele and occult lesions such as tethered cord. It commonly produces neurogenic bladder dysfunction requiring urodynamic surveillance and a bowel and bladder management program.

Bladder dysfunction caused by neurologic disease or injury, producing failure to store or empty urine depending on the level and completeness of the lesion. Management aims to protect the upper tracts by keeping bladder pressures low and ensuring regular emptying.

Regular passage of a catheter by the patient or caregiver to empty the bladder completely, used when spontaneous voiding is incomplete or unsafe. It is the mainstay of bladder management in neurogenic bladder and after certain reconstructive operations.

Physiologic testing of bladder filling and emptying that measures pressures, volumes, compliance, and detrusor activity. It identifies unsafe storage pressures and dyssynergia and guides treatment in neurogenic bladder, valve bladder, and refractory voiding dysfunction.

Involuntary contraction of the external urethral sphincter during detrusor contraction, causing obstructed voiding and high bladder pressures. It is common in spinal cord lesions and threatens the upper urinary tract if not managed.

Abnormal voiding pattern in a neurologically normal child, often from habitual pelvic floor contraction during voiding, leading to incomplete emptying, urinary tract infection, and incontinence. Treatment combines education, timed voiding, and pelvic floor relaxation training.

Storage disorder marked by urgency, frequency, and urge incontinence due to uninhibited detrusor contractions in a neurologically intact child. It is managed first with bladder training, fluids, and constipation treatment, then with anticholinergic medication if needed.

Noninvasive measurement of urine flow rate and pattern during voiding. A flattened or interrupted curve suggests bladder outlet obstruction or dysfunctional voiding, and the test is often combined with postvoid residual measurement.

Placeholder duplicate entry reserved to avoid confusion; see vesicoureteral reflux defined elsewhere in this list.

Noninvasive stone treatment that uses focused shock waves to fragment calculi, which then pass in the urine. It is used in selected children with renal stones of appropriate size and composition, with attention to stone burden and anatomic obstruction.

Endoscopic passage of a small scope through the urethra and bladder into the ureter to visualize and treat stones or other lesions. In children it is often used for ureteral stones and allows laser lithotripsy with high stone-free rates.

Excessive calcium excretion in the urine, a common metabolic cause of pediatric stones and of urinary tract symptoms such as hematuria or dysuria. It is assessed by a 24-hour urine collection or spot calcium-to-creatinine ratio and treated with hydration and dietary measures.

Elevated blood pressure caused by renal parenchymal disease or renal artery narrowing. It is an important cause of secondary hypertension in children and may require imaging of the renal vasculature and, in selected cases, revascularization.

Surgical placement of a donor kidney, usually in the iliac fossa with the ureter reimplanted into the bladder, as definitive therapy for end-stage kidney disease. Children require careful urologic assessment beforehand because abnormal bladders or prior surgery affect outcomes.