Obstructive Diseases

Question 1

What is hydronephrosis

Answer 1

Dilation of the renal pelvis and calyces associated with progressive atrophy of the kidney secondary to obstruction

Question 2

Effects of prolonged obstruction

Answer 2

Interstitial inflammation –> Fibrosis

GFR drop late due to resorption of filtrate into interstitium into lymphatic and venous system.

Question 3

Morphology of sudden, complete obstruction

Answer 3

Mild dilation of the pelvis and calyces

Question 4

Morphology of subtotal, intermitent obstruction

Answer 4

GFR not suppressed, Progressive dilation

Question 5

Presentation of chronic obstructive disease

Answer 5

Cortical tubular atrophy

Blunting of pyramidal atrophy (become cupped)

Question 6

Presentation of advanced cases

Answer 6

Striking parenchyma atrophy
Obiteration of pyramids
Thinning of Cortex

Question 7

Clinical features of obstructive disease

Answer 7

Pain from distention of the collecting system
Loss of urine conc. w/ bilateral partial
May see acidosis, renal calculi
HTN is common
Oligo/anuria with bilateral obstruction

Question 8

Name the four main stone types

Answer 8

Calcium Oxalate
Triple/Struvite Stones
Uric Acid
Cysteine

Question 9

MAP/Struvite stones are formed after infections with…

Answer 9

urea splitting bacteria (proteus, staph)

Question 10

Important things associated with stone formation

Answer 10

Increased concentration of stone constituents
Decreased urine volumes
Changes in urine pH
Bacteria presence

Question 11

General features of pyelonephritis

Answer 11

Acute: Bacterial
Chronic: Bacteria in face of vesicoureteral reflux or obstruction

Question 12

85% of pyelonephritis is caused by ____ bacteria

Answer 12

Gram Negative (E coli, Proteus, Klebsiella) from the patients own fecal flora

Question 13

Infection from bladder to kidney is assocaitd with development of

Answer 13

Vesicoureteral reflex

Question 14

Intrarenal reflux most commonly affects….

Answer 14

the poles

Question 15

Important morphological details of acute pyelonephritis

Answer 15

Patchy interstitial suppurative inflamm and tubular necrosis

Chronic abscesses destroy engulfed tubules

Question 16

IMportant complications of acute pyelonephritis

Answer 16

Papillary Necrosis (esp. w/ diabetes + UTI)
Pyelonephrosis seen in obs. where suppurative exhudate can't drain

Question 17

Clinical features of acute pyelonephritis

Answer 17

UTI-like symptoms, Fever, Costovertebral angle pain
Leukocyte casts
Recurrence if obstruction isn’t relieved

Question 18

Morphological features of chronic pyelonephritis

Answer 18

Kidneys are irregularly scarred in poles
Coarse, discrete, corticomedullary scar overlying a deformed calyx
Chronic Inflammation of tubules/interstitium
Xanthogranulomatous pyelonephritis

Question 19

Describe the chronic inflammation seen in chronic pyelonephritis

Answer 19

Tubules show areas of hypertrophy
Diluted tubules filled with coloid casts (thyroidization)
Obliterative endarteritis
Can progress to glomeruli

Question 20

Describe xanthogranulomatous pyelonephritis

Answer 20

Involves foamy macrophages and plasma cells

Especially associated with Proteus infections

Question 21

Clinical features of chronic pyelonephritis

Answer 21

presents late in disease with renal insufficiency + HTN

Focal segemental glmerulosclerosis

Question 22

Important details about reflux nephropathy

Answer 22

Common cause of chronic pyeloneph. scarring
Reflux from early age
Infections
Common cause of HTN in children
Chronic – Eventual focal segmental glomerulosclerosis

Question 23

Most common causes of congenital obstructions

Answer 23

Posterior Urethral Valves
Ureteropelvic jxn narrowing
vesicoureteral reflux