Hydronephrosis: Introduction Causes Pathophysiology Clinical Features Investigations Treatment

1. HYDRONEPHROSIS
AND PYONEPHROSIS
Presented by:
Anish Dhakal
(Aryan)

2. CONTENTS
• Introduction
• Causes
• Pathophysiology
• Clinical Features
• Investigations
• Treatment

3. • Hydronephrosis is an aseptic dilatation of the kidney caused
by obstruction
• Dilation of renal pelvis and calyces associated with
progressive atrophy of the kidney
• Urine outflow obstruction
• Obstructive uropathy indicates impedance of urinary flow
anywhere along the urinary tract, upper or lower and
damage to the renal parenchyma due to obstruction at any
site

4. HYDRONEPHROSIS: CAUSES
Causes of Unilateral Ureteric Obstruction
Extramural obstruction:
Adjacent structures neoplasm like those of cervix, prostate,
rectum, colon or caecum
Idiopathic retroperitoneal fibrosis
Retrocaval ureter
Intramural obstruction:
Congenital stenosis, physiological narrowing of the pelviureteric
junction leading to pelviureteric junction obstruction
Ureterocele and congenital small ureteric orifice

5. CAUSES OF UNILATERAL URETERIC
OBSTRUCTION
Intramural obstruction:
 Inflammatory stricture following removal of ureteric calculus,
repair of a damaged ureter or tuberculous infection
 Neoplasm of the ureter or bladder cancer involving the ureteric
orifice
Intraluminal obstruction:
 Calculus in the pelvis or ureter
 Sloughed papilla in papillary necrosis (more commonly in
diabetics, analgesic abusers and sickle cell disease)

6. BILATERAL HYDRONEPHROSIS
It is commonly result of urethral obstruction.
Causes:
Congenital
 Posterior urethral valves
 Urethral atresia
Acquired
 Benign prostatic enlargement
 Carcinoma of the prostate
 Postoperative bladder neck scarring
 Urethral stricture
 Phimosis

8. PATHOPHYSIOLOGY
• Even with complete obstruction, glomerular filtration persists
for some time
• The filtrate diffuses back to the interstitium an perirenal
spaces
• Affected calyces and pelvis becomes dilated
• High pressure transmitted through collecting ducts:
Cortex: Renal atrophy
Medulla: Renal vasculature compression with diminished
inner medullar blood flow
• The kidney becomes a thin walled, lobulated, fluid filled
sac

9. PATHOPHYSIOLOGY
• Effective hydroureteronephrosis on renal function depends
on whether it is totally or partially obstructive and unilateral
or bilateral
• Effects of obstruction of the kidney are time dependent.
Within several hours, changes are evident but:
1–2 week:glomerular destruction, tubular atrophy,
and interstitial fibrosis occur
By 6–8 week: irreversible damage occurs

11. • Early stage: Elongation and dilatation of ureters due to mild obstruction
• Later stage: Further dilatation and elongation with kinking of the ureter, fibrous
band causes further kinking

12. CLINICAL FEATURES
Unilateral Hydronephrosis ( commonly by idiopathic
pelvicureteric junction obstruction or calculus)
• More common in women and on right side
• May remain silent for long periods, being apparent in course of
imaging studies (about 3% of population)
• Mild pain or dull aching in loin (dragging heaviness worsened by
excessive fluid intake)
• Kidney may be palpable
• Intermittent Hydronephrosis (Dietl’s crisis)

13. CLINICAL FEATURES
Bilateral Hydronephrosis:
 Loin pain
 Features of bladder outlet obstruction: Polyuria, Nocturia,
Dysuria, Hesitancy
 Kidneys usually not palpable
 Inability to concentrate urine which may be associated with
distal tubular acidosis, chronic tubulointerstitial nephritis, renal
and renal salt wasting

14. CLINICAL FEATURES
• Complete Bilateral Obstruction:
Rapid onset oliguria or anuria that is incompatible with
survival until obstruction is relieved. After relief, post
obstructive diuresis with large amount of sodium chloride
• Ureters and pelvis dilatation in pregnancy:
Up to 20th week .Back to normal within 12 weeks of delivery
Effect of high progesterone on smooth muscles

15. POSSIBLE EXAMINATION
FINDINGS
• General condition: pain or localized symptoms
• Abdominal, flank, or pelvic mass
• Flank tenderness can occur along with acute obstruction
and with calculi or infection
• Vaginal exam– Ureteral prolapse
• Digital rectal exam– Enlarged prostate, nodularity suggestive
of prostate cancer

16. INVESTIGATIONS
• Ultrasound scanning:
least invasive, regularly used for pelviureteric junction
obstruction
• Intravenous Pyelogram:
Significant function in obstructed kidney
Contrast fills the obstructed system down to blockage
Can take follow up films 36 hours after the injection of
contrast

17. INVESTIGATIONS
Isotope renography
 Best to confirm obstructive dilatation of collecting system
 Technetium 99m-labelled DTPA (diethylenetriaminepenta-
acetic acid or MAG-3) injected intravenously and tracked
using gamma camera
 99mTc-DTPA stays in renal pelvis in obstructed site

18. Isotope renogram series shows a late accumulation and
persistence of radioactivity in the left kidney

19. INVESTIGATIONS
Whitaker test
 Percutaneous puncture made in kidney, fluid is infused at
constant rate with monitoring intrapelvic pressure,
 Abnormal rise in intrapelvic pressure confirms obstruction
Retrograde Pyelography
 Confirms site of obstruction
 Done immediately before corrective surgery

21. TREATMENT
• Hydronephrosis is not a specific diagnosis but a finding or
sign
• Management is highly dependent on underlying condition
and the timing (acute vs. chronic)
• Urgent decompression is needed with:
– Severe pain
– Active urinary tract infection and acute kidney insufficiency
– Retrograde ureteral stent or percutaneous
nephrostomy can provide equally effective drainage

22. MEDICAL THERAPY
• Patients with infection and hydronephrosis require antibiotic
therapy and drainage
• Renal failure and electrolyte abnormalities should be
corrected in conjunction with drainage
• Along with these, catheter drainage may be required as well

23. TREATMENT
• Indications for surgery:
Bouts of renal pain
Increasing Hydronephrosis
Evidence of parenchymal damage and infection
• Mild cases followed by serial ultrasound scans and operated
upon if dilatation is increasing
• Nephrectomy considered only when kidney largely
destroyed

24. ANDERSONS-HYNES
PYELOPLASTY
• Upper third of ureter and renal pelvis is mobilized
• Renal vein can be divided but artery should be preserved
• Anastomosis formed in front of artery
• A nephrostomy tube or ureteric stent protects the
anastomosis
• Laparoscopic pyeloplasty, a minimal access procedure is
becoming increasingly popular

26. ENDOSCOPIC
PYELOPLASTY
• Disruption of pelviureteric junction by a balloon passed up
the ureter and distended under radiographic control
• Long term efficacy still need to be proved

27. PYONEPHROSIS

28. PYONEPHROSIS
• Greek (Pyon + Nephros)
• Infection following:
1. Hydronephrosis
2. Acute pyelonephritis
3. Renal calculus disease
Kidney becomes multilocular sac containing pus or
purulent urine

29. CLINICAL FEATURES
• Triad of
1. Anaemia
2. Fever
3. Loin swelling
• Symptoms of cystitis (burning sensation, persistent urge to
urinate, increased frequency, haematuria, pelvic discomfort,
fever)
• Infected Hydronephrosis: Large swelling, high grade fever
with rigors

30. INVESTIGATIONS
• May reveal calculus (complication: most common cause)
• Dilatation of pus filled collecting system

31. TREATMENT
• Surgical emergency due to high risk of permanent renal
damage and lethal septicaemia
• Parenteral antibiotics along with kidney drain
• Percutaneous nephrostomy, if pus is too thick open
nephrostomy is considered
• Nephrectomy is appropriate if kidney is totally destroyed
and the contralateral side kidney function is good

32. REFERENCES:
1) Smith and Tanagho, General Urology, 18th
Edition
2) Norman S. Williams et al, Bailey & Love’s
Short Practice of Surgery, 26th Edition
3) Gomella, Leonard G, 5 Minute Urology
Consult, 3rd Edition