Renal Diagnostics

Question 1

What lab measurement is released into the circulation at a relatively constant rate, has a stable plasma concentration, and is freely filtered across the glomerulus and excreted by the kidney?

Answer 1

Serum creatinine

Question 2

What lab measurement is a product of protein catabolism, is excreted by the kidneys, and can be elevated with dehydration, GI bleed, or meds such as steroids and tetracyclines?

Answer 2

BUN

Question 3

What lab measurement is commonly used as a marker for volume status?

Answer 3

BUN/ creatinine ratio

Question 4

What measurement is used to measure the # of functioning nephrons and is used to track progression/ regression of disease and dose medications?

Answer 4

GFR

Question 5

Can GFR be measured directly?

Answer 5

No, must be calculated

Question 6

Creatinine clearance is helpful to know when what?

Answer 6

Choosing or dosing meds

Question 7

CKD is defined as the presence of kidney damage or decreased kidney function for how long?

Answer 7

≥ 3 months

Question 8

If a pt presents w hx of no urine output, what should you be concerned about? (generally)

Answer 8

Very concerning- renal failure

Question 9

What stage of kidney disease is a pt considered if they are on dialysis?

Answer 9

End stage renal disease/ kidney failure

Question 10

Pt with the following is in what stage of CKD? Kidney damage with N or ↑ GFR GFR ≥ 90

Answer 10

Stage 1

Question 11

Pt with the following is in what stage of CKD? Kidney damage with N or ↓ GFR GFR 60-89

Answer 11

Stage 2

Question 12

Pt with the following is in what stage of CKD? Moderately ↓ GFR (30-59)

Answer 12

Stage 3

Question 13

Pt with the following is in what stage of CKD? Severe ↓ GFR (15-29)

Answer 13

Stage 4

Question 14

Pt with the following is in what stage of CKD? Kidney failure GFR < 15 or on dialysis

Answer 14

Stage 5

Question 15

You might order ANA levels if you suspect what?

Answer 15

SLE

Question 16

You might order C-ANCA and P-ANCA levels if you suspect what?

Answer 16

Granulomatosis w polyangitis

Question 17

You might order anti-GBM levels if you suspect what?

Answer 17

Goodpasture syndrome

Question 18

You might order antistreptolysin O levels if you suspect what?

Answer 18

Post-strep glomerulonephritis

Question 19

You might order SPEP and UPEP levels if you suspect what?

Answer 19

Multiple myeloma

Question 20

What lab value has the potential to improve estimates of GFR?

Answer 20

Cystatin C

Question 21

Prostate-specific antigen (PSA) can be used for what?

Answer 21

Screening for early detection of prostate cancer and to monitor disease after treatment

Question 22

When should you consider testing PSA levels in men?

Answer 22

Consider ~50 yo (but shared decision making)

Question 23

Men with an abn PSA should be what?

Answer 23

Referred to urology

Question 24

What 2 values on a urinalysis can indicate possible kidney issues?

Answer 24

Protein and blood (always further investigate)

Question 25

What test is used in the work-up to find the cause of kidney disease?

Answer 25

Microscopic urinalysis

Question 26

On microscopic urinalysis, a pt with glomerulonephritis or vasculitis might show what?

Answer 26

RBC casts

Question 27

On microscopic urinalysis, a pt with acute pyelonephritis might show what?

Answer 27

WBC casts

Question 28

On microscopic urinalysis, a pt with acute tubular necrosis might show what?

Answer 28

Epithelial cell casts

Question 29

On microscopic urinalysis, a pt with dehydration might show what?

Answer 29

Hyaline casts

Question 30

On microscopic urinalysis, a pt with abn levels of uric acid, calcium phosphate or calcium oxalate, cystine, or magnesium ammonium phosphate (struvite) might show what?

Answer 30

Crystals

Question 31

What urine study id's the causative organism of a urinary infection and shows sensitive and resistance abx?

Answer 31

Urine C+S

Question 32

What urine finding serves as the earliest clinically detectable stage of diabetic nephropathy?

Answer 32

Microalbumin

Question 33

What urine study is most commonly seen in acute interstitial nephritis?

Answer 33

Urine eosinophils

Question 34

What urine study provides a better quantitative measurement for proteinuria or GFR determination?

Answer 34

24-hour urine collection

Question 35

Bence Jones are a positive for what test, leading to suspicion for MM?

Answer 35

Urine protein immunoelectrophoresis (UPEP)

Question 36

What may be a helpful initial diagnostic tool but is not typically used clinically?

Answer 36

Abd x-ray (KUB or abd)

Question 37

While a KUB study can identify calcium-containing, struvite, and cysteine stones, what will it likely miss (making it NOT 1st line imaging)?

Answer 37

Smaller stones, radiolucent stones (uric acid) or stones overlying bony structures

Question 38

What are stones involving the renal pelvis and extending into ≥ 2 calyces?

Answer 38

Staghorn

Question 39

What is the appropriate initial test in patients with renal failure of unknown etiology?

Answer 39

Renal US

Question 40

What is the test of choice to exclude urinary tract obstruction?

Answer 40

Renal US

Question 41

What is the test of choice for evaluating renal vascular flow?

Answer 41

Renal doppler US (can also use CT angiography)

Question 42

What imaging provides more detailed info than US, helps distinguish between types of cysts and masses, and is used to eval and stage renal cell carcinoma?

Answer 42

CT scan

Question 43

What is the diagnostic test of choice for nephrolithiasis?

Answer 43

Non-contrast CT

Question 44

What cautions should you be aware of when using a contrast CT?

Answer 44

Contrast potentially nephrotoxic Hold metformin for 48 hrs post

Question 45

What is the gold standard for diagnosis of renal vein thrombosis?

Answer 45

MRI

Question 46

What c/i should you be aware of with Gadolinium in MRI testing?

Answer 46

May increase risk of nephrogenic systemic fibrosis in pts with chronic or acute renal failure

Question 47

What diagnostic test is used to eval size/ shape of kidneys/ ureters/ bladder, kidney stones, and obstruction (although NOT used frequently)?

Answer 47

Intravenous pyelogram (IVP)

Question 48

How is excretory fxn of the kidneys measured with IVP?

Answer 48

Length of time for passage of contrast through kidneys

Question 49

What test is used for preoperative mapping of renal vasculature (if needed)?

Answer 49

Renal angiography

Question 50

What might you be concerned for if you see bilateral radiopaque branched, staghorn calculi filling on collecting systems on KUB?

Answer 50

Nephrolithiasis

Question 51

What might you be concerned for if you see triangular hypodense streaks spreading from the pelvis to the renal cortex on CT scan?

Answer 51

Bilateral pyelonephritis

Question 52

What might you be concerned for if you see a "string of pearls" appearance on angiography?

Answer 52

Fibromuscular dysplasia

Question 53

What test is used to obtain a renal sample to assist with dx?

Answer 53

Renal bx

Question 54

What test involves the bladder being filled with contrast and x-rays being taken to visualize contrast?

Answer 54

Cystourethrogram

Question 55

Primary bladder conditions such as vesicoureteral reflux, distortion of the bladder, fistula, and perforation are better seen with what study (compared to IVP)?

Answer 55

Cystourethrogram

Question 56

What test is a scope of the bladder involving a thin fiberoptic tube passed through a hollow sheath?

Answer 56

Cystoscopy

Question 57

What should be expected post cystoscopy, and how soon after should this clear?

Answer 57

Post-procedure hematuria, should clear w/i 3 voids

Question 58

What test is used to assess bladder and ureteral involvement due to malignancies, to eval urogynecologic conditions, and to dx intrinsic bladder disease?

Answer 58

Cystoscopy

Question 59

What should be ordered in all male pts complaining of testicular pain?

Answer 59

Testicular US

Question 60

What test is used to eval of testicular/ scrotal masses or pain, testicular size, location of undescended testes and what else should you get with this test?

Answer 60

Testicular US, should also get a doppler to look at BF

Question 61

How is a prostate US and biopsy performed and what does it help detect?

Answer 61

Transrectally Helpful in detection of prostate cancer in pts with increased PSA