Tubular And Intersitial Diseases

Question 1

__________ is the most common cause of acute renal failure

Answer 1

ATN (acute tubular necrosis)

Question 2

What are some histological findings in someone with ATN?

Answer 2

• can see tubular epithelial cells that have become detached from BM and then sloughed into the tubular lumen
• some tubules are swollen or vacuolated
• blabbing and loss of brush border of tubules

Question 3

What happens in the initiation phase of ATN?

Answer 3

36 hrs

• Acute DECREASE in GFR
• rapid ↑ in serum creatinine and BUN

Question 4

What happens in the maintenance phase of ATN?

Answer 4

• plateau of serum creatinine and BUN

- uremic symptoms, hyperkalemia, metabolic acidosis

Question 5

Muddy brown granular casts are seen in the urine analysis of what renal pathology?

Answer 5

ATN

Question 6

List the urinary findings in someone with ATN?

Answer 6

• muddy brown granular casts
• epithelial cell casts
• free epithelial cells
• mild proteinuria
• mild microscopic hematuria
• NO PYURIA

( can also be normal in less severe disease)

Question 7

What are examples of uremic signs seen in ATN?

Answer 7

• pericardial friction rub and confusion

Question 8

What are the two main general causes of ATN?

Answer 8

• ischemic insult: hypotension, hemorrhagic/hypvolemic shock

- nephrotoxic insult: endogenous and exogenous

Question 9

______________ drugs are exogenous nephrotoxic cause of ATN

Answer 9

Aminoglycosides, especially gentamicin

Question 10

What is the difference in the pattern of necrosis seen in ischemic type ATN vs toxic type ATN

Answer 10

Ischemic: patchy; (PST and ascending limbs of loop of Henle are the most vulnerable)
Toxic: more diffuse and affects the PCT (not affected in ischemic type)

Question 11

______________ is seen in both types of ATN

Answer 11

Casts in the DCT and CD

Question 12

What are some features that you would see due to tubular dysfunction in tubulointerstitial nephritis?

Answer 12

• impaired urinary concentration (polyuria which is large volumes of dilute urine and nocturia)
• salt wasting (hyponatremia)
• metabolic acidosis due to inability to excrete acid

Question 13

ATN has oliguria/polyuria?

Answer 13

Oliguria;

Polyuria is seen in TIN

Question 14

What is the most common cause for acute TIN?

Answer 14

Drugs: antibiotics, NSAIDs, PPI’s such as omeprazole
Other: infection, idiopathic and sarcoidosis (sarcoidosis will have granuloma TIN)

Question 15

What kind of TIN would be caused by pyelonephritis?

Answer 15

chronic TIN

Question 16

Drug induced interstitial nephritis will have prominent ___________ and mononuclear cell infiltrate. This is type ____ TIN

Answer 16

Eosinophils; type 1

Question 17

What drugs most commonly cause TIN?

Answer 17

• NSAIDs
• omeprazole (PPI)
• antibiotics

Question 18

What is a typical presentation of someone who most likely has TIN?

Answer 18

• patient can take a drug (NSAIDs, antibiotics, PPI) and then 2 weeks later (1st exposure) or 3-5 days later (2nd exposure) will have: fever, rash, and/or eosinophilia

Question 19

Treatment for AIN:

Answer 19

• stop taking the drug

- oral steroids

Question 20

_________ and _________ infections could be a source for bloodstream causes for acute pyelonephritis

Answer 20

Bacteria endocarditis; septicemia

Question 21

What kind of people are at more risk for ascending infection causes for acute pyelonephritis

Answer 21

• women

- males with BPH or vesicourethral reflux

Question 22

The predominant cell in acute pyelonephritis is ________ inside the tubules a

Answer 22

Neutrophils/ neutrophilic casts (WBC cast)

Question 23

What are some complications of acute pyelonephritis?

Answer 23

• papillary necrosis
• pyonephrosis (pus collecting in the renal pelvis)
• perinephric abscess

Question 24

Blunting of the calyces and depressed areas on gross specimen of the kidney is seen in what renal disease?

Answer 24

Chronic pyelonephritis

Question 25

Thyroidization of the tubules is a form of tubular atrophy and is seen in ________

Answer 25

Chronic pyelonephritis

Question 26

What are the two forms of chronic pyelonephritis

Answer 26

• chronic obstructive pyelonephritis: incompetent posterior urethral valves or kidney stones
• reflux nephropathy (vesicourethral reflux)

Question 27

Preferentially scarring and calyceal dilation at the poles is seen in _______________

Answer 27

VUR form of chronic pyelonephritis

Question 28

What are some gross features of a kidney that has undergone the obstructive form of chronic pyelonephritis?

Answer 28

• diffuse dilation of calyces and scarring

Question 29

What are some common causes of obstructive uropahty (obstruction at any level in the urinary tract from urethra to renal pelvis)

Answer 29

• BPH
• bladder cancer
• kidney stone
• retroperitoneal adenopathy
• papillary necrosis due to sloughed papillae obstructing the tract

Question 30

What is the most common type of renal stones?

Answer 30

Calcium containing: calcium oxalate and calcium phosphate

Question 31

____________ renal stones are typically secondary to infection

Answer 31

Struvite (Mg/ammonium phosphate);

These stones are also very large and to take the shape of the renal pelvis when they get lodged there

Question 32

With _________ stones in the kidney, you can see granulomatous inflammation

Answer 32

Uric acid

Question 33

Abrupt onset of flank pain radiation to groin (intermittent) is indicative of _______

Answer 33

Renal stone that is lodged in the ureter (pain is described as renal colic)

Question 34

What are 3 ways to prevent renal stones?

Answer 34

• ↑ fluid intake
• ↓ sodium diet (calcium and sodium get absorbed together in the PCT so by ↓ sodium will lead to ↓ urinary calcium excretion)
• alkalinization of urine to ↑ solubility of uric acid

Question 35

____________ urine has ↑ solubility for uric acid

Answer 35

Alkaline