renal ix

Question 1

list the renal screen

Answer 1

Blood tests for effects of renal disease:
Blood tests for causes of renal disease:
Urine tests: dipstick, MCS
Imaging: Renal ultrasound, CTKUB
Specimens: Renal biopsy

Question 2

urine consistently low specific gravity

Answer 2

CKD (failure of the kidneys to concentrate the urine)
diabetes insipidus (deficiency of ADH resulting in passage of a large volume of dilute urine)

Question 3

urine high specific gravity

Answer 3

fluid volume depletion
diabetes mellitus (large amounts of glucose)

Question 4

alkaline urine

Answer 4

iatrogenic - treating myoglobinuria or recurrent urinary calculi due to uric acid or cystine
distal renal tubular acidosis - early morning urine consistently alkaline and cannot be acidified
UTIs with urea-splitting organisms (proteus mirabilis) - causes alkaline urine that favours renal struvite stone formation

Question 5

causes of proteinuria

Answer 5

renal disease

functional

Question 6

functional causes of proteinuria

Answer 6

postoperative
really high blood pressure
overloaded heart (CHF)
temperature (fever, burns)
exercise
ingestion of alcohol (acute alcohol abuse)
new blood (blood transfusion)

Question 7

nephrotic syndrome secondary causes (classification)

Answer 7

drugs
infections
malignancy
systemic disease

Question 8

drug causes of nephrotic syndrome

Answer 8

penicillamine, lithium, heroin, NSAIDs

Question 9

systemic disease causes of nephrotic syndrome

Answer 9

SLE, diabetes, amyloidosis

Question 10

malignant causes of nephrotic syndrome

Answer 10

carcinoma, lymphoma, multiple myeloma

Question 11

infectious causes of nephrotic syndrome

Answer 11

HBV, HCV, HIV, IE, malaria

Question 12

causes of glycosuria

Answer 12

diabetes mellitus

Question 13

causes of ketonuria

Answer 13

DKA, starvation

Question 14

what to look for in urine sediment

Answer 14

RBCs, WBCs, casts

Question 15

normal RBC range in sediment

Answer 15

usually 0, up to <5RBCs/LPF if very concentrated

Question 16

ddx for RBCs in sediment

Answer 16

glomeruli (>80% RBCs are dysmorphic - irregular in size and shape)
renal tract (RBCs uniform)

Question 17

normal WBC range in sediment

Answer 17

usually <10 WBCs/HPF if very concentrated urine

Question 18

pyuria ddx

Answer 18

UT inflammation. either:
infection - bacteria (more likely if squamous epithelial cells present)
sterile pyuria - renal TB, acute/chronic tubulo-interstitial disease

Question 19

meaning of casts in sediment

Answer 19

damaged glomerular basement membrane or tubules

Question 20

categories of casts

Answer 20

hyaline
granular
red cell
white cell
fatty

Question 21

red cell casts

Answer 21

GN

Question 22

white cell casts

Answer 22

bacterial pyelonephritis

less commonly: GN, kidney infarction, vasculitis

Question 23

fatty casts

Answer 23

nephrotic syndrome

Question 24

what to look for on renal ultrasound

Answer 24

hydronephrosis, cysts, kidney size, anatomical abnormalities

Question 25

blood tests for effects of renal disease

Answer 25

Standard: FBE, UEC, LFT, CRP/ESR
Metabolic: glucose, CMP, PTH, vitamin D, uric acid
Protein: ACR, PCR (if patient is losing a lot of protein e.g. oedema), 24h urinary protein

Question 26

blood tests for causes of renal disease

Answer 26

Viral serology: HBV, HCV, HIV, CMV
Autoimmune: ANA, RF, anti-GBM, ANCA, ASOT
Complement and immune complexes: C3, C4, cryoglobulins
Serum protein electrophoresis

Question 27

what to look for on dipstick

Answer 27

specific gravity, blood, protein, nitrites, glucose, ketones, bilirubin

Question 28

what to look for on MCS

Answer 28

RBC, WBC, casts, bacteria