1. POSTERIOR URETHRAL VALVE
DR. Hamdan H. Alhazmi
MD,SBU,ABU
pediatric urologist
King Khalid University Hospital

2. INCIDENCE
ETIOLOGY
ANATOMY OF MALE URETHRA
EMBRYOLOGY
CLASSIFICATION
PATHOPYSIOLOGY
CLINICAL PRESENTATION
PROGNOSTIC FACTORS
DIAGNOSIS

3. Incidence
The most common structural cause of urinary outflow obstruction in pediatric practice
The most common type of obstructive uropathy leading to childhood renal failure
1 of every 5000 to 8000 male births
10% of prenatally diagnosed hydronephrosis
1 PUV in 1250 fetal ultrasound

4. ETIOLOGY
Not clear
Genetic factor are poorly undrerstood

5. ANATOMY OF MALE UTETHRA
ANTERIOR
- Penile Bulbar
POSTERIOR Prostatic Membranous

6. EMPRYOLOGY

9. CLASSIFICATION
Young classification 1919

11. 95% %
more serious

12. Type 1 PUV
Develop when the mesonephric ducts enter the cloaca more anteriorly than normal.

13. Type 3 PUV
Incomplete dissolution of the urogenital membrane

14. Pathopysiology
Primitive tissues mature in an abnormal environment of high intraluminal pressures and organ distention
UNIVERSAL INJURY
IN THE URINARY TRACT

15. RENAL DYSPLASIA
RENAL FUNCTION
RENAL TUBULAR FUNCTION
HYDRONEPHROSIS
VUR
VESICAL DYSFUNCTION
VALVE BLADDER

16. 1-Renal Dysplassia
Defined as a congenital defect of tissue development without premalignant potential
Histological diagnosis
Cause ? high pelvic pressure during nephrogenesis primary embryologic abnormality from abnormal position of uteteric bud

17. Commonly associated with PUV
Severity well determine ultimate renal function

18. 2-Renal Function
Children with PUV may demonstrate gradual loss of renal function over time
Cause: Renal parenchymal dysplasia 2- Incomplete relief of obstruction 3-parenchymal injury from : * UTI *HTN *Progressive glomerulosclerosis from hyperfiltration * Obstruction

19. ESRD
-Occurs in 25% - 40%
-1/3 soon after birth
-2/3 during late teenager

20. 3-Renal Tubular Function
50% of patients with PUV have impairment concentration ability
 Persistently high urinary flow rate regardless of fluid intake or state of hydration
 severe dehydration and electrolyte imbalance
 ureteral dilatation and high resting vesical pressure

21. 4-Hydronephrosis
Significant urethral obstruction  variable degree of ureteral dilatation
After relief of obstruction : gradual but substantial reduction of hydronephrosis
If not reduced we have to role out: High intravesical pressure ureteral muscle weakness UVJ obstruction

22. 5-Vesicoureteral Reflux
50% VUR at time of diagnosis
Primary or Secondary

23. 6-Vesical Dysfunction Commonly presented in patient with PUV
Usually primary secondary to irreversible change in organization and function of the smooth muscle from outlet obstruction
Present as as urinary incontinence (20%)
Bladder dysfunction persist in 75 % after valve ablation

24. - Myogenic failure and overflow incontinence (40%)
May cause deterioration of renal function
Three groups of dysfunction were described - Detrusor –hyperreflexia (29%) Hypertonic and poor compliant bladder (31%)
- Myogenic failure and overflow incontinence (40%)

25. 7-VALVE BLADDER
Even after relief of obstruction a significant number of patient will continue to have hpertonia and detrusor hyperreflexia and low compliance
Physiological obstruction of the ureter associated with bladder filling
 persistence hydronephrosis and/or urinary incontinence

26. PROGNOSTIC FACTOR Good Factors Nadir creatinine < 0.8 mg/dl
S. creatinine < 1 mg/dl
Pop-off mechanism
- VURD
- Ascitis
- Large bladder diverticulum

29. Bad Factors
Age
Delayed correction
GFR < 50 % of normal in infancy
VUR
- Bil > 57 % mortality
- Uni > 17 %
- Non > 9 %
Loss of cortico medullary junction
delayed incontinence beyond 5 years

31. Clinical presentation
Variable
Age dependent
= Prenatally : 70% of PUV by ltrasound
= Newborn: - Abdominal mass Ascites Respiratory distress Urosepsis Delayed viding or poor stream

32. = Infant: - Urinary dribbling. - Enuresis
= Infant: - Urinary dribbling Enuresis Failure to thrive/ renal failure Urosepsis
= Toddlers: UTI Voiding dysfunction
= School-age boy: Urinary incontinence

33. Diagnosis

34. Prenatal Ultrasound Change the the incidence of PUV
Prepare physician for immediate postnatal management
Finding: -bilateral hydroureteronephrosis -distended, thick wall bladder -+/- oligohydramnios
The earlier PUV detected the poorer the diagnosis

35. Postnatal Ultrasound
To evaluate the effect of PUV on the urinary tract rather than to diagnose PUV
Typical finding: wide prostatic urethra,thick-walled bladder,and upper tract dilatation
Assessment of renal parenchyma

37. MCUG
Gold standard for diagnosing PUV
Typically showed :

38. VUR in 50% of patients with PUV
Normal MCUG exclude PUV

39. Functional assessment
Diuretic Radioisotope Scan
- DTPA OR MAG-3
- with urethral catheter in place Exclude obstruction and assess split renal function
Serum Creatinine Immediately after birth reflect maternal createnin

40. THANK YOU