- •Preface
- •Acknowledgments
- •Contents
- •1.1 Introduction
- •1.2 Normal Embryology
- •1.3 Abnormalities of the Kidney
- •1.3.1 Renal Agenesis
- •1.3.2 Renal Hypoplasia
- •1.3.3 Supernumerary Kidneys
- •1.3.5 Polycystic Kidney Disease
- •1.3.6 Simple (Solitary) Renal Cyst
- •1.3.7 Renal Fusion and Renal Ectopia
- •1.3.8 Horseshoe Kidney
- •1.3.9 Crossed Fused Renal Ectopia
- •1.4 Abnormalities of the Ureter
- •1.5 Abnormalities of the Bladder
- •1.6 Abnormalities of the Penis and Urethra in Males
- •1.7 Abnormalities of Female External Genitalia
- •Further Reading
- •2.1 Introduction
- •2.2 Pathophysiology
- •2.3 Etiology of Hydronephrosis
- •2.5 Clinical Features
- •2.6 Investigations and Diagnosis
- •2.7 Treatment
- •2.8 Antenatal Hydronephrosis
- •Further Reading
- •3.1 Introduction
- •3.2 Embryology
- •3.3 Pathophysiology
- •3.4 Etiology of PUJ Obstruction
- •3.5 Clinical Features
- •3.6 Diagnosis and Investigations
- •3.7 Management of Newborns with PUJ Obstruction
- •3.8 Treatment
- •3.9 Post-operative Complications and Follow-Up
- •Further Reading
- •4: Renal Tumors in Children
- •4.1 Introduction
- •4.2 Wilms’ Tumor
- •4.2.1 Introduction
- •4.2.2 Etiology
- •4.2.3 Histopathology
- •4.2.4 Nephroblastomatosis
- •4.2.5 Clinical Features
- •4.2.6 Risk Factors for Wilms’ Tumor
- •4.2.7 Staging of Wilms Tumor
- •4.2.8 Investigations
- •4.2.9 Prognosis and Complications of Wilms Tumor
- •4.2.10 Surgical Considerations
- •4.2.11 Surgical Complications
- •4.2.12 Prognosis and Outcome
- •4.2.13 Extrarenal Wilms’ Tumors
- •4.3 Mesoblastic Nephroma
- •4.3.1 Introduction
- •4.3.3 Epidemiology
- •4.3.5 Clinical Features
- •4.3.6 Investigations
- •4.3.7 Treatment and Prognosis
- •4.4 Clear Cell Sarcoma of the Kidney (CCSK)
- •4.4.1 Introduction
- •4.4.2 Pathophysiology
- •4.4.3 Clinical Features
- •4.4.4 Investigations
- •4.4.5 Histopathology
- •4.4.6 Treatment
- •4.4.7 Prognosis
- •4.5 Malignant Rhabdoid Tumor of the Kidney
- •4.5.1 Introduction
- •4.5.2 Etiology and Pathophysiology
- •4.5.3 Histologic Findings
- •4.5.4 Clinical Features
- •4.5.5 Investigations and Diagnosis
- •4.5.6 Treatment and Outcome
- •4.5.7 Mortality/Morbidity
- •4.6 Renal Cell Carcinoma in Children
- •4.6.1 Introduction
- •4.6.2 Histopathology
- •4.6.4 Staging
- •4.6.5 Clinical Features
- •4.6.6 Investigations
- •4.6.7 Management
- •4.6.8 Prognosis
- •4.7 Angiomyolipoma of the Kidney
- •4.7.1 Introduction
- •4.7.2 Histopathology
- •4.7.4 Clinical Features
- •4.7.5 Investigations
- •4.7.6 Treatment and Prognosis
- •4.8 Renal Lymphoma
- •4.8.1 Introduction
- •4.8.2 Etiology and Pathogenesis
- •4.8.3 Diagnosis
- •4.8.4 Clinical Features
- •4.8.5 Treatment and Prognosis
- •4.9 Ossifying Renal Tumor of Infancy
- •4.10 Metanephric Adenoma
- •4.10.1 Introduction
- •4.10.2 Histopathology
- •4.10.3 Diagnosis
- •4.10.4 Clinical Features
- •4.10.5 Treatment
- •4.11 Multilocular Cystic Renal Tumor
- •Further Reading
- •Wilms’ Tumor
- •Mesoblastic Nephroma
- •Renal Cell Carcinoma in Children
- •Angiomyolipoma of the Kidney
- •Renal Lymphoma
- •Ossifying Renal Tumor of Infancy
- •Metanephric Adenoma
- •Multilocular Cystic Renal Tumor
- •5.1 Introduction
- •5.2 Embryology
- •5.4 Histologic Findings
- •5.7 Associated Anomalies
- •5.8 Clinical Features
- •5.9 Investigations
- •5.10 Treatment
- •Further Reading
- •6: Congenital Ureteral Anomalies
- •6.1 Etiology
- •6.2 Clinical Features
- •6.3 Investigations and Diagnosis
- •6.4 Duplex (Duplicated) System
- •6.4.1 Introduction
- •6.4.3 Clinical Features
- •6.4.4 Investigations
- •6.4.5 Treatment and Prognosis
- •6.5 Ectopic Ureter
- •6.5.1 Introduction
- •6.5.3 Clinical Features
- •6.5.4 Diagnosis
- •6.5.5 Surgical Treatment
- •6.6 Ureterocele
- •6.6.1 Introduction
- •6.6.3 Clinical Features
- •6.6.4 Investigations and Diagnosis
- •6.6.5 Treatment
- •6.6.5.1 Surgical Interventions
- •6.8 Mega Ureter
- •Further Reading
- •7: Congenital Megaureter
- •7.1 Introduction
- •7.3 Etiology and Pathophysiology
- •7.4 Clinical Presentation
- •7.5 Investigations and Diagnosis
- •7.6 Treatment and Prognosis
- •7.7 Complications
- •Further Reading
- •8.1 Introduction
- •8.2 Pathophysiology
- •8.4 Etiology of VUR
- •8.5 Clinical Features
- •8.6 Investigations
- •8.7 Management
- •8.7.1 Medical Treatment of VUR
- •8.7.2 Antibiotics Used for Prophylaxis
- •8.7.3 Anticholinergics
- •8.7.4 Surveillance
- •8.8 Surgical Therapy of VUR
- •8.8.1 Indications for Surgical Interventions
- •8.8.2 Indications for Surgical Interventions Based on Age at Diagnosis and the Presence or Absence of Renal Lesions
- •8.8.3 Endoscopic Injection
- •8.8.4 Surgical Management
- •8.9 Mortality/Morbidity
- •Further Reading
- •9: Pediatric Urolithiasis
- •9.1 Introduction
- •9.2 Etiology
- •9.4 Clinical Features
- •9.5 Investigations
- •9.6 Complications of Urolithiasis
- •9.7 Management
- •Further Reading
- •10.1 Introduction
- •10.2 Embryology of Persistent Müllerian Duct Syndrome
- •10.3 Etiology and Inheritance of PMDS
- •10.5 Clinical Features
- •10.6 Treatment
- •10.7 Prognosis
- •Further Reading
- •11.1 Introduction
- •11.2 Physiology and Bladder Function
- •11.2.1 Micturition
- •11.3 Pathophysiological Changes of NBSD
- •11.4 Etiology and Clinical Features
- •11.5 Investigations and Diagnosis
- •11.7 Management
- •11.8 Clean Intermittent Catheterization
- •11.9 Anticholinergics
- •11.10 Botulinum Toxin Type A
- •11.11 Tricyclic Antidepressant Drugs
- •11.12 Surgical Management
- •Further Reading
- •12.1 Introduction
- •12.2 Etiology
- •12.3 Pathophysiology
- •12.4 Clinical Features
- •12.5 Investigations and Diagnosis
- •12.6 Management
- •Further Reading
- •13.1 Introduction
- •13.2 Embryology
- •13.3 Epispadias
- •13.3.1 Introduction
- •13.3.2 Etiology
- •13.3.4 Treatment
- •13.3.6 Female Epispadias
- •13.3.7 Surgical Repair of Female Epispadias
- •13.3.8 Prognosis
- •13.4 Bladder Exstrophy
- •13.4.1 Introduction
- •13.4.2 Associated Anomalies
- •13.4.3 Principles of Surgical Management of Bladder Exstrophy
- •13.4.4 Evaluation and Management
- •13.5 Cloacal Exstrophy
- •13.5.1 Introduction
- •13.5.2 Skeletal Changes in Cloacal Exstrophy
- •13.5.3 Etiology and Pathogenesis
- •13.5.4 Prenatal Diagnosis
- •13.5.5 Associated Anomalies
- •13.5.8 Surgical Reconstruction
- •13.5.9 Management of Urinary Incontinence
- •13.5.10 Prognosis
- •13.5.11 Complications
- •Further Reading
- •14.1 Introduction
- •14.2 Etiology
- •14.3 Clinical Features
- •14.4 Associated Anomalies
- •14.5 Diagnosis
- •14.6 Treatment and Prognosis
- •Further Reading
- •15: Cloacal Anomalies
- •15.1 Introduction
- •15.2 Associated Anomalies
- •15.4 Clinical Features
- •15.5 Investigations
- •Further Reading
- •16: Urachal Remnants
- •16.1 Introduction
- •16.2 Embryology
- •16.4 Clinical Features
- •16.5 Tumors and Urachal Remnants
- •16.6 Management
- •Further Reading
- •17: Inguinal Hernias and Hydroceles
- •17.1 Introduction
- •17.2 Inguinal Hernia
- •17.2.1 Incidence
- •17.2.2 Etiology
- •17.2.3 Clinical Features
- •17.2.4 Variants of Hernia
- •17.2.6 Treatment
- •17.2.7 Complications of Inguinal Herniotomy
- •17.3 Hydrocele
- •17.3.1 Embryology
- •17.3.3 Treatment
- •Further Reading
- •18: Cloacal Exstrophy
- •18.1 Introduction
- •18.2 Etiology and Pathogenesis
- •18.3 Associated Anomalies
- •18.4 Clinical Features and Management
- •Further Reading
- •19: Posterior Urethral Valve
- •19.1 Introduction
- •19.2 Embryology
- •19.3 Pathophysiology
- •19.5 Clinical Features
- •19.6 Investigations and Diagnosis
- •19.7 Management
- •19.8 Medications Used in Patients with PUV
- •19.10 Long-Term Outcomes
- •19.10.3 Bladder Dysfunction
- •19.10.4 Renal Transplantation
- •19.10.5 Fertility
- •Further Reading
- •20.1 Introduction
- •20.2 Embryology
- •20.4 Clinical Features
- •20.5 Investigations
- •20.6 Treatment
- •20.7 The Müllerian Duct Cyst
- •Further Reading
- •21: Hypospadias
- •21.1 Introduction
- •21.2 Effects of Hypospadias
- •21.3 Embryology
- •21.4 Etiology of Hypospadias
- •21.5 Associated Anomalies
- •21.7 Clinical Features of Hypospadias
- •21.8 Treatment
- •21.9 Urinary Diversion
- •21.10 Postoperative Complications
- •Further Reading
- •22: Male Circumcision
- •22.1 Introduction
- •22.2 Anatomy and Pathophysiology
- •22.3 History of Circumcision
- •22.4 Pain Management
- •22.5 Indications for Circumcision
- •22.6 Contraindications to Circumcision
- •22.7 Surgical Procedure
- •22.8 Complications of Circumcision
- •Further Reading
- •23: Priapism in Children
- •23.1 Introduction
- •23.2 Pathophysiology
- •23.3 Etiology
- •23.5 Clinical Features
- •23.6 Investigations
- •23.7 Management
- •23.8 Prognosis
- •23.9 Priapism and Sickle Cell Disease
- •23.9.1 Introduction
- •23.9.2 Epidemiology
- •23.9.4 Pathophysiology
- •23.9.5 Clinical Features
- •23.9.6 Treatment
- •23.9.7 Prevention of Stuttering Priapism
- •23.9.8 Complications of Priapism and Prognosis
- •Further Reading
- •24.1 Introduction
- •24.2 Embryology and Normal Testicular Development and Descent
- •24.4 Causes of Undescended Testes and Risk Factors
- •24.5 Histopathology
- •24.7 Clinical Features and Diagnosis
- •24.8 Treatment
- •24.8.1 Success of Surgical Treatment
- •24.9 Complications of Orchidopexy
- •24.10 Infertility and Undescended Testes
- •24.11 Undescended Testes and the Risk of Cancer
- •Further Reading
- •25: Varicocele
- •25.1 Introduction
- •25.2 Etiology
- •25.3 Pathophysiology
- •25.4 Grading of Varicoceles
- •25.5 Clinical Features
- •25.6 Diagnosis
- •25.7 Treatment
- •25.8 Postoperative Complications
- •25.9 Prognosis
- •Further Reading
- •26.1 Introduction
- •26.2 Etiology and Risk Factors
- •26.3 Diagnosis
- •26.4 Intermittent Testicular Torsion
- •26.6 Effects of Testicular Torsion
- •26.7 Clinical Features
- •26.8 Treatment
- •26.9.1 Introduction
- •26.9.2 Etiology of Extravaginal Torsion
- •26.9.3 Clinical Features
- •26.9.4 Treatment
- •26.10 Torsion of the Testicular or Epididymal Appendage
- •26.10.1 Introduction
- •26.10.2 Embryology
- •26.10.3 Clinical Features
- •26.10.4 Investigations and Treatment
- •Further Reading
- •27: Testicular Tumors in Children
- •27.1 Introduction
- •27.4 Etiology of Testicular Tumors
- •27.5 Clinical Features
- •27.6 Staging
- •27.6.1 Regional Lymph Node Staging
- •27.7 Investigations
- •27.8 Treatment
- •27.9 Yolk Sac Tumor
- •27.10 Teratoma
- •27.11 Mixed Germ Cell Tumor
- •27.12 Stromal Tumors
- •27.13 Simple Testicular Cyst
- •27.14 Epidermoid Cysts
- •27.15 Testicular Microlithiasis (TM)
- •27.16 Gonadoblastoma
- •27.17 Cystic Dysplasia of the Testes
- •27.18 Leukemia and Lymphoma
- •27.19 Paratesticular Rhabdomyosarcoma
- •27.20 Prognosis and Outcome
- •Further Reading
- •28: Splenogonadal Fusion
- •28.1 Introduction
- •28.2 Etiology
- •28.4 Associated Anomalies
- •28.5 Clinical Features
- •28.6 Investigations
- •28.7 Treatment
- •Further Reading
- •29: Acute Scrotum
- •29.1 Introduction
- •29.2 Torsion of Testes
- •29.2.1 Introduction
- •29.2.3 Etiology
- •29.2.4 Clinical Features
- •29.2.5 Effects of Torsion of Testes
- •29.2.6 Investigations
- •29.2.7 Treatment
- •29.3 Torsion of the Testicular or Epididymal Appendage
- •29.3.1 Introduction
- •29.3.2 Embryology
- •29.3.3 Clinical Features
- •29.3.4 Investigations and Treatment
- •29.4.1 Introduction
- •29.4.2 Etiology
- •29.4.3 Clinical Features
- •29.4.4 Investigations and Treatment
- •29.5 Idiopathic Scrotal Edema
- •29.6 Testicular Trauma
- •29.7 Other Causes of Acute Scrotum
- •29.8 Splenogonadal Fusion
- •Further Reading
- •30.1 Introduction
- •30.2 Imperforate Hymen
- •30.3 Vaginal Atresia
- •30.5 Associated Anomalies
- •30.6 Embryology
- •30.7 Clinical Features
- •30.8 Investigations
- •30.9 Management
- •Further Reading
- •31: Disorders of Sexual Development
- •31.1 Introduction
- •31.2 Embryology
- •31.3 Sexual and Gonadal Differentiation
- •31.5 Evaluation of a Newborn with DSD
- •31.6 Diagnosis and Investigations
- •31.7 Management of Patients with DSD
- •31.8 Surgical Corrections of DSD
- •31.9 Congenital Adrenal Hyperplasia (CAH)
- •31.10 Androgen Insensitivity Syndrome (Testicular Feminization Syndrome)
- •31.13 Gonadal Dysgenesis
- •31.15 Ovotestis Disorders of Sexual Development
- •31.16 Other Rare Disorders of Sexual Development
- •Further Reading
- •Index
8.4 Etiology of VUR |
247 |
|
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Figs. 8.21 and 8.22 Diagrammatic representation of grade II VUR and a micturating cystourethrogram showing grade II VUR
Fig. 8.23 A micturating cystourethrogram showing grade III VUR
•Grade V – Reflux with gross dilation of ureter, pelvis, and calyces, loss of papillary impressions, and ureteral tortuosity (Figs. 8.29, 8.30, and 8.31)
8.4Etiology of VUR
•VUR is prevented by a one way valve like effect at the uretero-vesical junction.
•This is attributed to several factors including:
–The oblique entrance of the ureter into the urinary bladder
–The submucosal tunnel through which the ureter enter into the urinary bladder
–The ureter’s muscular attachments
•Failure of this mechanism will result in retrograde flow of urine.
•VUR is divided into two types based on etiology:
–Primary VUR
–Secondary VUR
•Primary VUR:
–Primary VUR is the most common form of reflux
–It is due to incompetent or inadequate ureterovesical junction (UVJ)
248 |
8 Vesicoureteral Reflux (VUR) in Children |
|
|
Figs. 8.24 and 8.25 Diagrammatic representation of grade III VUR and a micturating cystourethrogram showing grade III VUR. Note the hydronephrotic pelvic right kidney
–The exact cause of the defect in primary VUR is unknown
–This may be secondary to an abnormally short intravesical ureteric segment or abnormal surrounding muscles.
–Other factors that contribute to the etiology of primary VUR include:
•The existence of a strong genetic component is supported by the high rate of reflux in relatives of patients with reflux, but the mechanism of transmission is not clear.
•The possibility of urinary tract infection as a cause of VUR is not clear and many think that UTI and VUR are independent variables. Urinary tract infections may cause reflux due to the elevated pressures associated with inflammation.
•Secondary VUR:
–Secondary VUR is reflux that is associated with or caused by an obstructed or poorly functioning lower urinary tract.
–This is seen in children with congenital bladder outlet obstruction and neurogenic bladder (Figs. 8.32 and 8.33).
–More than 50 % of boys with posterior urethral valves have vesicoureteral reflux (Figs. 8.34 and 8.35).
–In these patients, VUR can be unilateral or bilateral
–Other causes include urethral or meatal stenosis
–Bladder instability, neurogenic bladder and non-neurogenic bladder
–Dysfunctional voiding, with its inherent increase in intravesical pressure, is a cause reflux, even in otherwise healthy children.
–The combination of high-pressure voiding and vesicoureteral reflux increases the risk of pyelonephritis beyond that of the child with low-pressure reflux.
–A unique group of children presents with dysfunctional elimination, which consists
8.4 Etiology of VUR |
249 |
|
|
Figs. 8.26, 8.27, and 8.28 Diagrammatic representation of grade IV VUR and Micturating cystourethrograms showing grade IV VUR
of a symptom complex heralded by |
– Hardikar syndrome: This include: |
|
infection, severe constipation, and daytime |
• |
Vesicoureteral reflux |
wetting (Figs. 8.36, 8.37, and 8.38). |
• |
Hydronephrosis |
– Some of these children have infrequent void- |
• Cleft lip and palate |
|
ing and incomplete bladder emptying, which |
• |
Intestinal obstruction and other |
further increases the likelihood of UTI. |
|
symptoms |
250 8 Vesicoureteral Reflux (VUR) in Children
8.5 Clinical Features
• VUR cannot be diagnosed prenatally. |
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• VUR however may be suspected in the prena- |
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tal period, when transient dilatation of the |
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upper urinary tract is noted in conjunction |
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with bladder emptying. |
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• |
Approximately 10 % of neonates diagnosed |
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prenatally with dilatation of the upper uri- |
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nary tract will be found to have VUR |
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postnatally. |
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• In |
general, |
VUR |
is almost |
always |
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asymptomatic. |
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• |
VUR does not cause any specific signs or |
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symptoms unless complicated by UTI (febrile |
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UTI). |
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• Most infants and children with vesicoureteral |
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reflux (VUR) present in one of two distinct |
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groups: |
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– The first group presents with hydronephro- |
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sis, often prenatally identified using |
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ultrasonography. |
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– |
The second |
group |
presents with |
urinary |
Fig. 8.29 Diagrammatic representation of grade V VUR |
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tract infection (UTI). |
|
Figs. 8.30 and 8.31 A micturating cystourethrogram showing grade V VUR. Note the dilated tortuous ureters
8.5 Clinical Features |
251 |
|
|
Etiology of VUR
•Primary causes of VUR:
–Short or absent intravesical ureter
–Absence of adequate detrusor backing
–Lateral displacement of the ureteral orifice
–Paraureteral (Hutch) diverticulum
•Secondary causes of VUR:
–Cystitis or UTI
–Bladder outlet obstruction (Posterior urethral valve, urethral stricture, meatal stenosis)
–Neurogenic bladder
–Detrusor instability
•Clinical signs and symptoms associated with a febrile UTI in a neonate may include:
–Irritability
–Persistent high fever
–Listlessness
–Infection in infants can manifest as failure to thrive, with or without fever.
–Other features include vomiting, diarrhea, anorexia, and lethargy
•In cases of VUR and febrile UTI associated with a serious underlying urinary tract abnormality, the neonate could present with respiratory distress, failure to thrive, renal failure, flank masses, and urinary ascites.
Figs. 8.32 and 8.33 Micturating cystourethrograms showing neurogenic bladder with VUR
252 |
8 Vesicoureteral Reflux (VUR) in Children |
|
|
Figs. 8.34 and 8.35 Micturating cystourethrograms showing posterior urethral valve and severe right vesicoureteral reflux. Note the dilated posterior urethra
•Older children with VUR and UTI may present with:
–Nonspecific signs and symptoms
–Urgency
–Frequency
–Dysuria
–Abdominal pain
–Incontinence
–Unless the UTI is associated with a fever, there is little reason to suspect VUR.
–Sometimes an enlarged urinary bladder may be palpable (Fig. 8.39).
–A palpable kidney is sometimes seen in those with associated hydronephrosis. Usually the affected kidney is not palpable
and small in size as measured by ultrasound.
–Children occasionally present with advanced reflux nephropathy, manifesting as headaches or congestive heart failure from untreated hypertension, or with uremic symptoms from renal failure.
–A small group of children without evidence of UTI present with symptoms of sterile reflux, which can include flank or abdominal pain before or during voiding, as well as double voiding or incomplete emptying resulting from delayed drainage of urine out of the upper tracts.
8.5 Clinical Features |
253 |
|
|
Figs. 8.36, 8.37, and 8.38 Plain abdominal radiograph and micturating cystourethrogram showing bowel dysfunction with chronic constipation and VUR