tubule-interstitial diseases of the kidney

Question 1

what kind of kidney injury are tubulointerstitial diseases?

Answer 1

intrinsic kidney injury

Question 2

acute tubulointerstitial nephritis definition

Answer 2

an acute inflammation of the renal interstitial and tubules that causes a decline in renal function over days to weeks

Question 3

acute interstitial nephritis urine findings

Answer 3

WBCs, eosinophils

WBC casts

Question 4

acute tubular necrosis urine findings

Answer 4

muddy brown granular casts

renal tubular epithelial cells/casts

Question 5

Acute tubular injury/necrosis pathophys

Answer 5

ischemic or toxic injury to tubular cells causes cells to swell and undergo apoptosis/necrosis
cell debris obstructs tubules leading to decreased GFR

Question 6

ischemic causes of ATN

Answer 6

blood loss
hypotension
septic shock
aortic surgery

Question 7

toxic causes of ATN

Answer 7

radiocontrast
abx: aminoglycosides
amphotericin B
antivirals
Chemo (cisplatin)

Question 8

presentation of ischemic ATN

Answer 8

low BP
shock syndrome
blood loss signs
oliguria (<400ml/day)

Question 9

toxic ATN clinical presentation

Answer 9

non-specific
tends to have non-oliguric urine flow because there is less tubular injury

get a good history to find out if a drug could be causing it

Question 10

ATN lab findings

Answer 10

increased BUN and Cr
hyperkalemia
metabolic acidosis
uremia
granular cases and tubular casts in urine

Question 11

granular casts usually indicate

Answer 11

acute tubular injury

Question 12

difference in urination between toxic and ischemic ATN

Answer 12

toxic=non-oliguria

ischemic=oliguria

Question 13

toxic ATI/ATN is very common among ___

Answer 13

ill hospitalized patients (10-20% of patients!)

Question 14

acute interstitial nephritis pathophys

Answer 14

usually a drug allergy

acute attack on tubules by inflammatory (T) cells. T cells migrate into tubule lumens which become obstructed leading to kidney injury and GFR decline

Question 15

AIN clinical presentation

Answer 15

often asymptomatic

fever, malaise, rash, arthralgia, flank pain

Question 16

AIN etiology

Answer 16

inflammation due to:
allergic response
autoimmune response
infectious response

Question 17

AIN diagnosis

Answer 17

clinical context (new drug, disease)
WBCs/casts in urine
kidney biopsy is definitive

Question 18

AIN kidney biopsy findings

Answer 18

interstitial cellular infiltrate with T cells and tubulitis

Question 19

chronic interstitial nephritis definition

Answer 19

chronic inflammation of the renal interstitial and tubules that usually progresses to tubular atrophy and interstitial fibrosis

Question 20

causes of chronic interstitial nephritis

Answer 20

drugs
chronic infection in the bladder
autoimmune
heavy metals
infiltrative diseases
metabolic diseases

Question 21

chronic interstitial nephritis clinical features

Answer 21

asymptomatic,

fatigue, fever, nocturne, polyuria

Question 22

chronic interstitial nephritis labs and imaging

Answer 22

BUN and Cr increase slowly

renal US shows small echogenic kidneys

Question 23

chronic interstitial nephritis urinalysis

Answer 23

bland urine sediment
waxy or granular casts
+/- WBC cells/casts

Question 24

renal sarcoidosis

Answer 24

granulomatous multi-system autoimmune disease that affects the kidneys

Question 25

primary and enteric hyperoxaluria

Answer 25

elevated level of oxalic acid in urine leading to calcium oxalate crystal deposition in the kidneys common in pts with gastric bypass or taking weight loss rx

Question 26

autosomal dominant polycystic kidney disease

Answer 26

a common inherited kidney disease due to a mutation on either chromosome 16 or 4 that leads to the development of multiple cysts in the kidneys

Question 27

PKD clinical presentation

Answer 27

usually asymptomatic until advanced | polyuria, hematuria, flank pain, HTN

Question 28

PKD diagnosis

Answer 28

kidney ultrasound is most commonly used CT scan or MRI showing 2-3 cysts in both kidneys

Question 29

PKD treatment

Answer 29

ACEi to lower BP increase water intake Tolvaptan to slow cyst growth