Posterior Urethral Valve Syndrome

1. Posterior Urethral Valve Syndrome Dr. Tricia A. Jacobsen 6/30/03

2. Initial Presentation 31 y/o G5P2022 EDC 9/10/03, LMP 12/7/02 – conceived on OCP’s Preg dated by LMP, conf by 7W1D u/s Prenatal course uncomplicated prior to admission

3. Past OB Hx 2 Spontaneous Abortions 2 Spontaneous Vaginal Deliveries - uncomplicated

4. Past GYN Hx No h/o of ovarian disease No abnormal Pap Smears No h/o STD’s Menses regular, began at age 12

5. Past Surgical Hx No surgical history

6. Past Medical Hx H/O Migraines Meds – Lo-estrin 1/20 with Fe NKDA Social – ¼ PPD cig. Occ ETOH

7. Prenatal labs O+, Antibody screen neg RI, VDRL NR Hep B Sag – neg HIV neg CBC – 6.8/13/36.7/304 Pap – WNL One hour Glucola – 52 Quad Screen – DS risk neg; 1:622

8. 16 week u/s – 4/2/03 Anatomy Scan – wnl Amniotic fluid – Volume wnl Normal IUP est. at 16w5d consistent with LMP EFW of 159 grams Placenta – fundal, no evidence of previa

9. 6/17/03 Called Attending MD c/o contractions c/o mild contractions or “Cramping” No LOF, No Vaginal bleeding Positive Fetal Movement Prenatal course uncomplicated until that day No other illnesses or symptoms

10. 6/17/03 cont. Pt sent for an ultrasound in Rocky Hill Found to have oligohydramnios with a 3 cm pocket Distended fetal bladder 4.9 cm by 2.9 cm Bilateral hydronephosis Pt sent to Labor and Delivery for complete evaluation

11. Evalulation on L&D – 6/17/03 PE - no acute distress, no h/a, scotomata - VS: 122/72, 84, 98.7 Lungs –CTA, no wheezing CV – RRR, S1S2 Abd – Soft, NT, +BS, no RUQ pain, + FM Ex – NT, no edema Spec – os appeared closed, Cultures sent, Nitrazine neg, fern neg, no pooling Pelvic – Cx long, thick, closed FHR – 130’s, reactive, Ave LTV, no variable, no decels Toco – negative – occasional cramp

12. Evaluation on L&D - 6/17/03 cont. Labs – O+, Antibody screen neg CBC – 8.8/12.2/34.0/252 Chem 7 – WNL U/A – WNL GC/CHL – neg/neg GBS - neg

13. 6/17/03 eval cont. U/S revealed 27 wk fetus in cephalic presentation, AFI < 3 cm, + FM, FB, Placenta anterior, Grade 1 Distended bladder noted, + hydronephrosis Pt admitted, Celestone started, MFM consulted and formal u/s ordered for the am Pt remained on L&D for continuous monitoring due to oligohydramnios

14. MFM Evaluation began 6/18/03 – formal ultrasound revealed Distended, thick walled bladder with a keyhole appearance in the area of the posterior urethra Ureters and renal calyces were distended Hydronephrosis – Left renal pelvis = 7 mm Right renal pelvis = 10 mm -- Amnioinfusion with 300 cc of warm normal saline was performed with asp. of 20 cc for chromosomal analysis

16. MFM Eval. Cont. Chromosomal (FISH) Analysis: Chrom #13 = 2 Chrom #18 = 2 Chrom #21 = 2 Chrom X = 1 Chrom Y = 1 Normal Male Fetus

17. Posterior Urethral Valve Syndrome Bladder outlet obstruction that is produced by a membrane within the posterior urethra Within the scope of obstructive uropathies Urethral atresia Persistent cloaca Chromosomal abnormalities Hypospadius, epispadius or stenosis

18. PUVS Cont. Incidence = 1 in 5,000 to 8,000 males Affects only males Most common cause of severe obstructive uropathies Etiology – may be failure of complete disintegration of the urogenital membrane

19. PUVS - Diagnosis Distended, thick walled bladder with a dilated posterior urethra – “Keyhole” app. Dilated ureters with b/l hydronephrosis Fluid volume/urine volume varies Presence of increased cortical echogenicity w/ or w/o cortical cysts may be consistent with renal dysplasia and a poor prognosis Cortical cysts are associated with irreverisble, advanced renal damage – fetus not amenable to intervention

20. Classic “Keyhole” Sign

21. Rt Kidney

22. Thickened bladder wall

23. Left Kidney

24. Distended Bladder

25. Dilated Rt and Lf Ureters

26. Dilated Right Kidney

27. Left Kidney

28. Left Kidney

29. Right Kidney

30. PUVS - Pathology Obstruction appear to be a diaphragmatic membrane with small opening in posterior urethra Simple mucosal membrane with fibrous stroma Dilatation of the prostatic urethra occurs b/w the obstructing membrane and the bladder neck

31. PUVS - Findings Elevated intravesicular pressures leading to reflux to ureters and renal pelvises Hydronephrosis develops from continued urine production with obstruction Renal pelvis and calyceal systems become distended, compress renal parenchyma

32. PUVS - Findings Histologically – Smooth muscle hypertrophy and hyperplasia within the bladder wall – increased bundle of smooth muscle Dilation of distal and proximal tubules associated with peritubular and interstitial fibrosis Fibrosis = echogenic appearance of the renal parenchyma on ultrasound

33. PUVS After 14 wks, amniotic fluid is dependent on fetal urine production Fetal swallowing, breathing, and AFI falls dramatically During 18 – 24 week from canalicular to alveolar phase results in underdeveloped lungs if no fluid

34. Work up – First step – ultrasound Bladder evaluated prior to and following drainage by fine needle vesicocentesis Overall size of bladder and degree of proximal urethral dilation (keyhole sign) Urethral and kidney evaluation for dilation or abnormalities, echogenicity, or cysts After vesicocentesis – the degree of bladder thickness is assessed Rule out other anomalies ie NTD, cardiac defects

35. WU – ultrasound cont Long axis of the kidney is measured when evaluating underlying hydronephrosis Kidneys which are large for gestational age and are less hyperechogenic – better prognosis Kidneys which are hyperechogenic and are small have poorer prognosis due to advanced renal fibrosis

36. Work up – Second step Prenatal evaluation for fetal karyotype Amniocentesis if fluid available – fluid may be infused the aspirated to obtain cells CVS if early – prelim results in 2-3 days Final results in 7-10 days May cultures cells from fetal urine – although more difficult to culture

37. Final Eval – Third step Evaluation of fetal kidney function with sequential vesicocenteses Completely drain fetal bladder at 48-72 hr intervals at a minimum of three occasions Fetuses w/ progressive hypotonicity and values that fall below threshold benefit from in utero intervention i.e. shunt placement

38. Needle Aspiration of Bladder

39. Eval cont Fetuses with isolated megacystis, bilateral hydronephrosis, decreased amniotic fluid volume, absent anomalies, a 46 XY karyotype and serially improving hypotonicity with values below the recommended thresholds would be candidates for vesicoamniotic shunt placement

40. Prognosis Outcome depends upon severity Classified as good or poor Poor prognostic factors include diagnosis before 24 wks, oligohydramnios, increased cortical echogenicity with cysts indicating renal dysplasia and marked hydronephrosis

41. Prognosis cont Fetuses that present with these findings have a very poor prognosis These die in the neonatal period from severe pulmonary hypoplasia Normal fluid volume with stable hydronephrosis have better outcomes Normal renal cortical echogenicity does not exclude renal dysplasia

42. Sonographic factors Good prog factors Normal fluid Diagnosis after 24 wk Asymmetric hydronephrosis Urinary ascites Isolated Poor prog factors Oligohydramnios Diagnosis before 24 wks Echogenic kidneys Perinephric urinoma Associated abnormalities

43. Urine Biochemistry

44. 6/19/03 – Bladder tap #1 Sodium - 116 mmol/L Chloride - 92 mmol/L U osm - 265 Protein - 112 mg/dl Calcium - 8.5 mg/dl

45. 6/20/03 Bladder tap #2 Sodium - 114 mmol/L Chloride - 90 mmol/L U osm - 249 Protein - 95 mg/dl Calcium - 9.2 mg/dl

46. 6/23/03 Bladder tap #3 Sodium - 118 mmol/L Chloride - 93 mmol/L U osm - 255 Protein - 113 mg/dl Calcium - 8.1 mg/dl

47. Management Poor prognosis group – may offer termination because infants ultimately die of pulmonary hypoplasia – or offer conservative management Fetuses with normal fluid and stable hydronephrosis – serial u/s until delivery Poor or good prognosis – depends upon serial renal urine biochemistries

48. Management cont Fetuses with good prognosis – placement of vesicoamniotic shunt with Rodeck catheter (double pigtail) Counsel re: rupture of membranes,infection, injury to fetus, intraplacental bleeding, PTL High density plastic with open metal tipped proximal and distal ends placed at fundal region – best fetal position vertex, back down Memory of the plastic allow return to shape Follow with serial u/s to confirm placement

49. Management Cont Consultation with pediatric urologist Route of delivery – routine obstetric indications Average age of delivery due to spontaneous rupture of membranes = 33-35 wks Following delivery – sterile ostomy bag to abdomen until renal function and anatomical evaluation by pediatric urologist

50. Summary PUVS – bladder outlet obstruction Affects 1 in 5,000 – 8,000 boys Etiology unknown Obstruction of posterior urethra Diagnosed by u/s Prognosis – dependent upon severity of hydronephrosis and urine chemistries

51. References Ultrasound and Fetal Therapy, “fetal shunt procedures” Johnson M.P., Feldman and M.I. Evans; chapter 1 Bettelheim et al, Prenatal diagnosis of fetal urinary ascits, Ultrasound Obstetrics and Gynecology 2000; 16: 473-475 Sonographic Diagnosis of Fetal Medicine, 634 – 637.