Updated: Oct 15, 2008
This article discusses various urethral anomalies observed in male infants and children and the distinct entity of urethral prolapse in prepubescent females. Urethral prolapse is a protrusion of urethral mucosa beyond the urethral meatus and generally occurs in prepubertal black girls or in postmenopausal white females. This article discusses the pediatric entity of urethral prolapse.
Similarities in the modes of presentation of these conditions are striking, underscoring the importance of a thorough history, physical examination, and radiologic imaging with careful and complete cystourethrography, ultrasonography, or endoscopy.
Lacuna magna
Lacuna magna, also known as sinus of Guérin, is a dorsal diverticulum in the roof of the fossa navicularis presenting either as a pit or a 4-mm to 6-mm sinus, dorsal and parallel to the urethra. This lesion is thought to arise embryologically from an incomplete fusion between the ingrowing ectoderm at the tip of the penis and the glandular urethra.
Urethral duplications
Urethral duplications are rare anomalies characterized as epispadiac, hypospadiac, and Y-type. They may be either complete, if venting externally, or incomplete, in which case the connection with the urinary tract varies. In complete duplications, the patient may void with a double stream. Epispadiac duplications are usually associated with significant dorsal curvature of the penis. The most common type of urethral duplication is the Y-type; individuals with Y-type urethral duplication have an orthotopic meatus and a perineal meatus, through which most of the urine passes. The etiology of these conditions is unknown.
Anterior urethral valves
Anterior urethral valves are rare anomalies, occurring 7-8 times less frequently than posterior urethral valves (PUV), but with consequences just as devastating. These lesions can occur anywhere in the anterior urethra, and the valve mechanism is usually formed by an associated diverticulum; isolated valves formed by cusps or irislike diaphragms have also been reported. The diverticulum has been postulated to arise from incomplete formation of the ventral corpus spongiosum, an incomplete urethral duplication, or a congenital cystic dilation of a periurethral gland. However, these lesions are embryologically distinct from the much more common PUV and occur distal to the urinary sphincter.
Megalourethra
Megalourethra can be described as a urethral diverticulum that affects the entire penile urethra. Two types, scaphoid and fusiform, have classic descriptions. Scaphoid megalourethras have an absence of corpus spongiosum, whereas fusiform megalourethras lack both spongiosum and corpora cavernosa. Often associated with lethal congenital anomalies, fusiform megalourethras are present in some stillborns; therefore, this finding has more academic than clinical pertinence. Temporary obstruction during early development may be an etiologic factor in fusiform megalourethra. In the scaphoid type, in which failure of development of erectile tissue is present, a mesenchymal defect is suggested akin to what is observed in prune belly syndrome.
Anterior urethral diverticula
Anterior urethral diverticula occur in males and may involve the proximal part of the penile urethra and the distal part of the bulbous urethra. An underlying defect in the spongiosum is suggested, as observed in scaphoid megalourethra, or, possibly, these lesions may result from the rupture of a periurethral cyst or a partial duplication of the urethra.
Urethral polyps
Urethral polyps are rare anomalies, characterized as benign urothelial-lined masses attached to a fibrovascular stalk arising from the verumontanum, presenting almost exclusively in boys. Urethral polyps' association to the verumontanum suggests the embryologic persistence of Müllerian structures. Some of these polyps, diagnosed later in life, may represent acquired lesions.
Cowper duct cysts
Cowper duct cysts involve the Cowper glands, 2 paired periurethral structures located in the urogenital diaphragm, which are drained by ducts measuring 2-3 cm long that empty into the bulbous urethra through 2 small, flush openings. These glands, homologous of the Bartholin gland in the female, secrete a clear fluid that functions as a lubricant and a coagulation factor for semen during ejaculation. Abnormalities of these glands and their ducts may result from obstruction and, less frequently, trauma and infection.
Urethral prolapse
Urethral prolapse is the complete protrusion of the urethral mucosa beyond the meatus in females. This is an uncommon condition observed particularly in prepubertal black and Latin American girls. Increased incidence has been reported in children from the lower socioeconomic strata. This condition is thought to result from poor attachments between the longitudinal and circular, oblique, smooth muscle layers and the mucosa of the urethra in association with recurrent episodes of increased intraabdominal pressure. Other contributing factors such as trauma, malnutrition, urinary and vaginal infections, and urethral mucosa redundancy have been postulated in the etiology of this condition.
Most conditions discussed in this article are infrequent or rare.
Although the dorsal urethral diverticulum in the roof of the fossa navicularis (ie, lacuna magna) may be present in approximately 30% of examined boys, this condition is rarely symptomatic. Urethral duplications are rare; only 150 cases had been reported in the literature prior to 1986. A ratio of the incidence of anterior urethral valves relative to that of PUV is 1:8; PUV occurs in 1 in 8000 to 1 in 25,000 live male births. Fewer than 50 cases of megalourethra had been reported in the literature by 1993; the scaphoid type is more common. Megalourethras have often been associated with other severe anomalies, such as prune belly syndrome, cloacal malformations, and the vertebral, anal, cardiac, tracheal, esophageal, renal, and limb (VACTERL) association of congenital anomalies.
Diverticula of the anterior urethra are uncommon but are the second most common form of congenital urethral obstruction, after PUV, in infants and children. Both Cowper duct cysts and congenital urethral polyps are quite rare. Urethral prolapse has an estimated incidence of 1 in 3000 and is most common in young black or Latin American girls.
Prepubertal black and Latin American girls have the highest incidence of urethral prolapse.
Urethral prolapse is the only condition discussed in this article that affects females.
Urethral prolapse in the pediatric population occurs most commonly in prepubertal black girls.
Because lacuna magna, anterior urethral valves, congenital urethral polyps, and Cowper duct cysts present with quite similar complaints, careful consideration of these urethral anomalies, along with a complete physical examination and appropriate imaging studies, are required to reach the correct diagnosis.
Many of the conditions discussed in this article may be suggested by history; however, the anomalies may not be obvious upon physical examination. Some of these conditions are clearly evident.
See Pathophysiology.
| Child Abuse & Neglect: Sexual Abuse | Urinary Tract Infection |
| Rhabdomyosarcoma | Voiding Dysfunction |
| Rhabdomyosarcoma: Surgical Perspective | |
| Ureteral Duplication, Ureteral Ectopia, and
Ureterocele | |
| Urethral Anomalies and Urethral Prolapse |
Prune belly syndrome
Urinary incontinence
Vaginal tumors (rhabdomyosarcoma)
Dysfunctional vaginal bleeding
Vaginitis
Bladder rhabdomyosarcoma
Urethral papilloma
Start treatment of pyelonephritis with a broad-spectrum intravenous antibiotic, which is modified according to sensitivities. Continue until the patient has been afebrile for 48 hours and the WBC count has normalized, at which time therapy can be switched safely to oral therapy.
These agents are used to treat pyelonephritis. Conventional treatment typically is initiated with a second-generation intravenous cephalosporin (eg, cefotaxime). Antibiotic regimens are adjusted later according to culture and sensitivities.
Third-generation cephalosporin with gram-negative spectrum. Lower efficacy against gram-positive organisms. Arrests bacterial cell wall synthesis, which, in turn, inhibits bacterial growth.
1-2 g IV/IM q6-8h
<1 week: 50 mg/kg/dose IV q12h
1-4 weeks: 50 mg/kg/dose IV q8h
Children <50 kg: 50-180 mg/kg/d IV/IM divided q4-6h
Probenecid may increase cefotaxime levels; coadministration with furosemide and aminoglycosides may increase nephrotoxicity
Documented hypersensitivity
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Adjust dose in severe renal impairment; has been associated with severe colitis
Usually used in combination with an aminoglycoside. Increased resistance to Escherichia coli is beginning to emerge. Exerts bactericidal activity against susceptible organisms.
500 mg to 3 g IV q4-6h; not to exceed 12 g/d
100-400 mg/kg/d IV/IM divided q4-6h
Probenecid and disulfiram elevate ampicillin levels; allopurinol decreases ampicillin effects and has additive effects on ampicillin rash; may decrease effects of PO contraceptives
Documented hypersensitivity
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Adjust dose in renal failure; evaluate rash and differentiate from hypersensitivity reaction
Aminoglycoside antibiotic for gram-negative coverage. Used in combination with both an agent against gram-positive organisms and one that covers anaerobes.
Loading dose and maintenance dose: 1-2.5 mg/kg IV and 1-1.5 mg/kg IV, respectively, q8h
Extended dosing regimen for life-threatening infections: 5 mg/kg/d IV/IM q6-8h
Follow each regimen by at least a trough level drawn 30 min prior to the third or fourth dose; may draw a peak level 0.5 h after 30-min infusion
<5 years: 2.5 mg/kg/dose IV/IM q8h
>5 years: 1.5-2.5 mg/kg/dose IV/IM q8h or 6-7.5 mg/kg/d divided q8h; not to exceed 300 mg/d; monitor as in adults
Coadministration with other aminoglycosides, cephalosporins, penicillins, and amphotericin B may increase nephrotoxicity; aminoglycosides enhance effects of neuromuscular blocking agents; thus, prolonged respiratory depression may occur
Coadministration with loop diuretics may increase auditory toxicity of aminoglycosides; possible irreversible hearing loss of varying degrees may occur (regularly monitor)
Documented hypersensitivity; non–dialysis-dependent renal insufficiency
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Narrow therapeutic index (not intended for long-term therapy); caution in renal failure (not on dialysis), myasthenia gravis, hypocalcemia, and conditions that depress neuromuscular transmission; adjust dose in renal impairment
AAP. Practice parameter: the diagnosis, treatment, and evaluation of the initial urinary tract infection in febrile infants and young children. Committee on Quality Improvement. Subcommittee on Urinary Tract Infection. Pediatrics. Apr 1999;103(4 Pt 1):843-52. [Medline].
Goldman M, Lahat E, Strauss S, et al. Imaging after urinary tract infection in male neonates. Pediatrics. Jun 2000;105(6):1232-5. [Medline].
Rushton HG, Parrott TS, Woodard JR, Walther M. The role of vesicostomy in the management of anterior urethral valves in neonates and infants. J Urol. Jul 1987;138(1):107-9. [Medline].
Agarwal S, Lall A, Bianchi A, Dickson A. Uro-genital bleeding in pre-menarcheal girls: dilemmas of child abuse. Pediatr Surg Int. Jun 2008;24(6):745-6. [Medline].
Johnson CF. Prolapse of the urethra: confusion of clinical and anatomic characteristics with sexual abuse. Pediatrics. May 1991;87(5):722-5. [Medline].
Anveden-Hertzberg L, Gauderer MW, Elder JS. Urethral prolapse: an often misdiagnosed cause of urogenital bleeding in girls. Pediatr Emerg Care. Aug 1995;11(4):212-4. [Medline].
Bartone FF. The urethra. In: O'Donnell B, Koff S, eds. Pediatric Urology. 3rd ed. Butterworth-Heinemann; 1994:526-36.
Casale AJ. Posterior urethral valves and other obstructions of the urethra. In: Gonzales ET, Bauer SB, eds. Pediatric Urology Practice. Lippincott Williams & Wilkins; 1999:240-4.
Fernandes ET, Dekermacher S, Sabadin MA, Vaz F. Urethral prolapse in children. Urology. Mar 1993;41(3):240-2. [Medline].
Jerkins GR, Verheeck K, Noe HN. Treatment of girls with urethral prolapse. J Urol. Oct 1984;132(4):732-3. [Medline].
Lowe FC, Hill GS, Jeffs RD, Brendler CB. Urethral prolapse in children: insights into etiology and management. J Urol. Jan 1986;135(1):100-3. [Medline].
Rudin JE, Geldt VG, Alecseev EB. Prolapse of urethral mucosa in white female children: experience with 58 cases. J Pediatr Surg. Mar 1997;32(3):423-5. [Medline].
Schoellnast H, Lindbichler F, Riccabona M. Sonographic diagnosis of urethral anomalies in infants: value of perineal sonography. J Ultrasound Med. Jun 2004;23(6):769-76. [Medline].
Shurtleff BT, Barone JG. Urethral prolapse: four quadrant excisional technique. J Pediatr Adolesc Gynecol. Aug 2002;15(4):209-11. [Medline].
Smith GH, Duckett JW. Urethral lesions in infants and children. In: Gillenwater JY, Grayhack JT, Howards SS, Duckett JW, eds. Adult and Pediatric Urology. 3rd ed. Mosby-Year Book; 1996:2431-43.
Valerie E, Gilchrist BF, Frischer J, et al. Diagnosis and treatment of urethral prolapse in children. Urology. Dec 1999;54(6):1082-4. [Medline].
urethral anomalies, urethral prolapse, lacuna magna, sinus of Guérin, urethral duplication, epispadiac urethral duplication, hypospadiac urethral duplication, Y-type urethral duplication, anterior urethral valves, urethral diverticula, anterior urethral diverticula, megalourethra, scaphoid megalourethra, fusiform megalourethras, urethral diverticulum, urethral polyps, congenital urethral polyps, Cowper duct cysts, urethral prolapse, prune belly syndrome, cloacal malformations, vertebral, anal, cardiac, tracheal, esophageal, renal, limb, VACTERL, posterior urethral valves, hydronephrosis, urinary tract infection, UTI
Jyoti Upadhyay, MD, FAAP, Consulting Staff, Children's Surgical Specialty Group, Children's Urology, Children's Hospital of the King's Daughters, Sentara Norfolk Hospital, Sentara Leigh Hospital
Jyoti Upadhyay, MD, FAAP is a member of the following medical societies: Alpha Omega Alpha, American Academy of Pediatrics, American Medical Association, American Urological Association, Endourological Society, and Society for Pediatric Urology
Disclosure: Nothing to disclose.
Carlos A Angel, MD, Associate Professor of Pediatrics, Division of Pediatric Surgery, University of Tennessee School of Medicine; Consulting Staff, East Tennessee Children's Hospital, East Tennessee Pediatric Surgery Group
Carlos A Angel, MD is a member of the following medical societies: American College of Surgeons, American Pediatric Surgical Association, British Association of Paediatric Surgeons, Children's Oncology Group, International Children's Continence Society, International Pediatric Endosurgery Group, New York Academy of Sciences, Society of Critical Care Medicine, and Texas Pediatric Society
Disclosure: Nothing to disclose.
Bartley G Cilento, Jr, MD, Instructor, Department of Surgery, Division of Urology, Children's Hospital of Boston and Harvard Medical School
Bartley G Cilento, Jr, MD is a member of the following medical societies: American Academy of Pediatrics, American Urological Association, and Massachusetts Medical Society
Disclosure: Nothing to disclose.
Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine
Disclosure: Pfizer Inc Stock Investment from financial planner; Avanir Pharma Stock Investment from financial planner ; WebMD Salary and stock Employment and investment from financial planner
Harry P Koo, MD, Chairman of Urology Division and Director of Pediatric Urology, Virginia Commonwealth University; Professor of Surgery, VCU School of Medicine, Medical College of Virginia; Director of Urology, Children's Hospital of Richmond
Harry P Koo, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Surgeons, and American Urological Association
Disclosure: Nothing to disclose.
Daniel Rauch, MD, FAAP, Director, Pediatric Hospitalist Program, Associate Professor, Department of Pediatrics, New York University School of Medicine
Daniel Rauch, MD, FAAP is a member of the following medical societies: Ambulatory Pediatric Association, American Academy of Pediatrics, and Society of Hospital Medicine
Disclosure: Baxter Honoraria Consulting
Marc Cendron, MD, Associate Professor of Surgery, Harvard School of Medicine; Consulting Staff, Department of Urological Surgery, Children's Hospital Boston
Marc Cendron, MD is a member of the following medical societies: American Academy of Pediatrics, American Urological Association, European Society for Paediatric Urology, Johns Hopkins Medical and Surgical Association, New Hampshire Medical Society, Society for Fetal Urology, and Society for Pediatric Urology
Disclosure: Nothing to disclose.
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