#24 Virmani- Renal Disease

Question 1

RB has uncontrolled hypertension and an active UTI. Would you be able to get a renal biopsy?

Answer 1

NO. Contraindicated in:

Uncontrolled HTN

Bleeding disorders

Active UTI

Single Kidney (except transplanted kidneys)

Question 2

What is the main clinical association?

Answer 2

Main clinical association

Glomerular disease (90%)

(picture of dysmorphic RBCs)

Question 3

Labs come back with 3 RBC and RBC casts in the urine. What does this suggest?

Answer 3

Microscopic hematuria with renal origin.

Question 4

Identify. Indicative of ?

Answer 4

WBC in urine

Pyuria

Question 5

Identify

Answer 5

Sheets of WBC in urine

Suggestive of Pyelonephritis

Question 6

Identify

Answer 6

Uric Acid Crystals

Flat with irregular shapes

Hyperuricosuria

Acute Uric Acid nephropathy

Gout

Question 7

Identify

Answer 7

Calcium oxalate crystals

Ethylene glycol poisoning

Envelope = Ethylene

Hyperoxaluria

Question 8

Identify

Answer 8

“Coffin Lid”

Alkaline urine with UTI

Triple Phosphate Crystals

Struvite stones

If you don’t like CATS (Coffin, Alkaline, Triple phospate, Struvite stones) you put them in a coffin.

Question 9

Identify

Answer 9

Cystine crystals

Seen in cystinuria

likely congenital

Hexagonal shape

Question 10

Identify

Answer 10

RBC Cast

Proliferative glomerular lesion

May be seen in acute interstitial nephritis

Question 11

Identify

Answer 11

WBC cast

Interstitial nephritis

Pyelonephritis

Question 12

Identify

Answer 12

Maltese cross

Lipid Bodies

Lipiduria

Question 13

Your patient has a disproportionate increase in BUN. What are your differential diagnoses?

Answer 13

Volume depletion (prerenal azotemia)

GI bleed

Steroids or cytotoxic agents

High protein diet

Obstructive Uropathy

Hyper-catabolic States (infectin, fever, hyperthyroidism, cancer)

BUN/Cr ratio >10:1

Question 14

BUN level is 18. Is this typically elevated, decreased or normal?

Answer 14

Normal

8-25 mg/dL

BUN varies inversely with GFR

Question 15

Your patient has a disproportionate decrease in BUN. What are your differential diagnoses?

Answer 15

Low protein diet

Liver disease/cirrhosis

Overhydration (SIADH)

Malnourishment

BUN/Cr less than 10:1

Question 16

Inulin is the ideal substance used to measure GFR because it is not reabsorbed, secrected, synthesized or metabolized. But since that is a pain, what endogenous substance is used and what formula is used?

Answer 16

Creatinine

CKD Epi

Breakdown of creatine phosphate

Question 17

In differentiating pre-renal azotemia from renal tubular disease, what equation would you use?

Answer 17

FeNa

Una/Pna X Pcr/Ucr

or

(Una/Pna) / (Ucr/Pcr)

Question 18

You are doing a macroscopic urinalysis and see green. What is that indicative of?

Red?

Yellow?

Turbidity?

Answer 18

Green - Urinary sedatives, triamterene, blue dyes

Red - blood, Hb, Mb, drugs (Phenitoin), dyes

Yellow - riboflavin, bilirubin (jaundice), pyridium, Rifampin

Turbidity - cells, casts, crystals

Question 19

You have a patient that had a negative dipstick proteinuria but a positive protein/creatinine ratio. What might this suggest?

Answer 19

Benze-Jones proteinuria

Multiple Myeloma

Question 20

You send a patient in for imaging because you want to distinguish if they have an obstruction or kidney atrophy. What kind of imaging will you order and why?

Answer 20

US

Non invasive, no contrast, painless

Can estimate kidney size, position and structural abnormalities

Detect obstruction, cysts, tumors

Locate best place for kidney biopsy

Question 21

What imaging would you use for renal artery stenosis?

Answer 21

CT or MRI

(Virmani - MRI)

Question 22

Why might you choose not to order an intravenous urography?

Answer 22

Does not work well on people with poorly functioning kidneys

Can cause contrast nephropathy