Kidney/Urinary: Congenital and Acute renal failure

Question 1

What is the most common congenital renal anomaly

Answer 1

horseshoe kidney

Question 2

What is horseshoe kidney

Answer 2

conjoined kidney usually at lower pole

Question 3

where is horseshoe kidney abnormally located

Answer 3

lower abdomen

Question 4

where do normal kidneys develop

Answer 4

pelvis

Question 5

what problem occurs when horseshoe kidney ascends from pelvis to lower abdomen

Answer 5

get caught on inferior mesenteric artery

Question 6

what is renal agenesis?

Answer 6

absent kidney formation

- may be unilateral or bilateral

Question 7

renal agenesis unilateral leads to what consequence?

Answer 7

hypertrophy of existing kidney

- hyperfiltration increases risk of renal failure later in life

Question 8

renal agenesis bilateral leads to what consequence?

Answer 8

oligohydramnios with lung hypoplasia

Potter’s sequence

Question 9

What are the symptoms for Potter’s sequence? Is it compatible with life?

Answer 9

flat face
low set ears
developmental defects of extremities
- incompatible with life

Question 10

what is dysplastic kidney disease

Answer 10

• inherited, congenital malformation of renal parenchyma characterized by cysts and abnormal tissue (cartilage)

Question 11

what is polycystic kidney disease

Answer 11

• inherited defect leading to bilateral enlarged kidneys with cysts in renal cortex and medulla

Question 12

what are two forms of polycystic kidney disease (PKD)

Answer 12

Autosomal recessive

Autosomal dominant

Question 13

autosomal recessive polycystic kidney disease presents in who? How does it present

Answer 13

infants

• worsening kidney failure and hypertension
• newborns present with Potter sequence

Question 14

autosomal recessive polycystic kidney disease is associated with what congenital abnormality

Answer 14

congenital hepatic fibrosis (leads to portal hypertension)

hepatic cysts

Question 15

Autosomal dominant polycystic kidney disease presents in who and clinical features

Answer 15

young adults

• hypertension ( due to increase renin)
• hematuria
• worsening renal failure

Question 16

autosomal dominant polycystic kidney disease is due to what mutation which causes what

Answer 16

APKD1 and APKD2

cysts develop over time

Question 17

autosomal dominant polycystic kidney disease is associated with what health problems

Answer 17

• berry aneurysm
• hepatic cysts
• mitral valve prolapse

Question 18

Which congenital kidney problem is not inherited

Answer 18

dysplastic kidney

Question 19

What happens to the size of kidneys in polycystic kidney disease

Answer 19

enlarged

Question 20

what is medullary cystic kidney disease inherited

Answer 20

autosomal dominant

Question 21

what is medullary cystic kidney disease

Answer 21

cysts in medullary collecting ducts

- parenchymal fibrosis results in shrunken kidneys and worsening renal failure

Question 22

oliguira

Answer 22

low production of urine

Question 23

azotemia? what lab values are associated with it

Answer 23

increase nitrogen-containing waste products in blood

- increased BUN and creatinine [Cr]

Question 24

what is a common cause of acute renal failure

Answer 24

prerenal azotemia

Question 25

what causes prerenal azotemia

Answer 25

decreased blood flow to kidneys

Question 26

how does prerenal azotemia impact the kidney, blood, and urine

Answer 26

decreases GF azotemia oliguria

Question 27

what is the BUN: Cr ration in prerenal azotemia and why?

Answer 27

greater than 15 | - reabsorption of fluid and BUN back into system

Question 28

what is the tubular function of prerenal azotemia? lab value?

Answer 28

remain intact | - fractional excretion of sodium [FENa] less than 1%

Question 29

what is the urine osmolality in prerenal azotemia

Answer 29

[osm] greater than 500 mOsm/kg

Question 30

what is postrenal azotemia

Answer 30

obstruction of urinary tract downstream from kidney

Question 31

how does postrenal azotemia impact the kidney, blood, and urine

Answer 31

- decrease GFR - azotemia - oliguria

Question 32

what happens during the early stages of postrenal azotemia? lab values?

Answer 32

1. increased tubular pressure 'forces' BUN into blood; BUN:Cr greater than 15 2. tubular function remains intact; FENa less than 1% 3. urine osmolality; osm greater than 500 mOsm/kg

Question 33

what happens during the later stages of postrenal azotemia? lab values

Answer 33

1. tubular damage , decrease absorption of BUN; BUN: Cr less than 15 2. decreased reabsorption of sodium; FENa greater than 2% 3. inability to concentrate urine; less than 500

Question 34

What is the MOST common cause of acute renal failure

Answer 34

acute tubular necrosis

Question 35

What is acute tubular necrosis

Answer 35

injury and necrosis of tubular epithelial cells | - necrotic cells plug tubules

Question 36

necrotic cells plug tubule in acute tubular necrosis, which causes what

Answer 36

- decrease GFR | - brown, granular casts seen in urine

Question 37

dysfunctional tubular epithelial cells in acute tubular necrosis results in

Answer 37

1. decreased reabsorption of BUN (serum BUN:Cr greater than 15) 2. decreased reabsorption of sodium ( FENa less than 2%) 3. inability to concentrate urine ( urine osm less than 500 )

Question 38

what are etiologies of acute tubular necrosis

Answer 38

ischemia and nephrotoxic

Question 39

what is ischemia of acute tubular necrosis

Answer 39

- decreased blood supply results in necrosis of tubules

Question 40

what usually precedes ischemia of acute tubular necrosis

Answer 40

prerenal azotemia

Question 41

what parts of the kidney are susceptible in ischemia acute tubular necrosis

Answer 41

proximal tubule and medullary segment of thick ascending limb

Question 42

what causes nephrotoxic acute tubular necrosis

Answer 42

toxic agents resulting in necrosis of tubules

Question 43

what part of the kidney is susceptible to nephrotoxic acute tubular necrosis?

Answer 43

proxmial tubule

Question 44

nephrotoxic acute tubular necrosis can be caused by

Answer 44

- aminoglycosides - heavy metals ( lead) - myoglobinuria ( from crush injury to muscle) - ethylene glycol ( associated with oxalate crystals in urine) - radiocontrast dye - urate ( tumor lysis syndrome)

Question 45

what is ethylene glycol? characteristics

Answer 45

anti-freeze | blue and sweet

Question 46

what is used prior to initiation of chemotherapy of acute tubular necrosis? this whole processes decreases what?

Answer 46

hydration and allopurinol decrease risk of urate-induced ATN

Question 47

what are clinical features of acute tubular necrosis

Answer 47

- oliguria with brown, granular casts - elevated BUN and creatinine - hyperkalemia ( due to decreased renal excretion) with metabolic acidosis

Question 48

Can you treat acute tubular necrosis

Answer 48

reversible, requires supportive dialysis, electrolyte imbalance can be fatal

Question 49

what happens in oliguria and tubular cells during recovery of acute tubular necrosis

Answer 49

- oliguria persists for 2-3 weeks before recovery | - tubular cells ( stable cells) take time to reenter the cell cycle and regenerate

Question 50

what is acute interstitial nephritis ? what causes it? what does it lead to?

Answer 50

- drug-induced hypersensitivity involving the interstitium and tubules - acute renal failure ( intrarenal azotemia)

Question 51

what are some causes of acute interstitial nephritis

Answer 51

NSAIDS penicillin diuretics

Question 52

clinically how does acute interstitial nephritis present

Answer 52

oliguria fever rash days to weeks after starting drug EOSINOPHILS may be present in urine

Question 53

how do you treat acute interstitial nephritis

Answer 53

stop taking drug

Question 54

what can acute interstitial nephritis progress to

Answer 54

renal papillary necrosis

Question 55

what is renal papillary necrosis

Answer 55

necrosis of renal papillae

Question 56

how does renal papillary necrosis present

Answer 56

gross hematuria and flank pain

Question 57

what are 4 causes of renal papillary necrosis

Answer 57

1. chronic analgesic abuse 2. diabetes mellitus 3. sickle cell trait/disease 4. severe acute pyelonephritis

Question 58

what can cause chronic analgesic abuse

Answer 58

long-term phenacetin or aspirin use