UA

Question 1

Acellular Casts

Answer 1

Hyaline, Waxy, Fatty, Granular, Pigmented, Crystal

Question 2

Hyaline Casts

Answer 2

MC type of cast

Solidified Tamm mucoprotein secreted from tubular epithelial cells of nephrons

Question 3

What contributes to the formation of hyaline casts?

Answer 3

Low urine flow
Concentrated urine
acidic environments
(seen in dehydrations or after vigorous exercise)

Question 4

Granular Casts

Answer 4

2nd MC cast
Results from the breakdown of cellular casts OR the inclusion of aggregates of plasma proteins such as albumin
(Known as “muddy brown casts”)

Question 5

What causes Granular casts

Answer 5

Chronic Renal Disease

Question 6

Waxy Casts

Answer 6

Larger then hyaline casts
Appearance= rigid, sharp edged, fractured, and/or broken off ends
(wider cast product of a dilated duct)

Question 7

What causes Waxy Casts

Answer 7

Longstanding Kidney Disease (CKD)

Question 8

Fatty Casts

Answer 8

Formed via the breakdown of lipid-rich epithelial cells
They appear as hyaline casts c fat globule inclusions, yellowish-tan in color
“Maltese cross” under polarized light

Question 9

Fatty casts are pathognomonic for

Answer 9

High urinary protein nephrotic syndrome

Question 10

Pigment Casts

Answer 10

Formed via the adhesion of metabolic b/d products or drug pigments

Question 11

Endogenously produced pigmented casts

Answer 11

Hemoglobin in hemolytic anemia, myoglobin in rhabdomyolysis, and bilirubin in liver dx.

Question 12

Crystal Casts

Answer 12

Crystallized urinary solutes, such as oxalates, urates, or sulfonamides
Clinical significance is low

Question 13

Cellular Casts

Answer 13

RBC casts
WBC casts
Bacterial Casts
Epithelial Casts

Question 14

RBC casts

Answer 14

ALWAYS PATHOLOGICAL
Strongly suggests glomerular dx
Also seen in vasculitis, SLE, post-strep glomerulonephritis, goodpasture’s syndrome. Renal infarction or subacute bacterial endocarditis

Question 15

WBC casts

Answer 15

Always come from the renal tubule
Inflammation or infection
Strongly suggests pyelonephritis
Can also be seen with acute allergic interstitial nephritis, nephrotic syndrome, post-strep acute glomerulonephritis

Question 16

Bacterial Casts

Answer 16

Pyelonephritis

Seen in association c bacteria, WBC, and WBC casts

Question 17

Epithelial cell casts

Answer 17

Formed via the adhesion of desquamated epithelial cells of the tubule lining
-Toxic ingestion (mercury, diethylene glycol, salicylate)
Organisms that cause death to the epithelial cells include cytomegalovirus & viral hep

Question 18

Indications for a UA

Answer 18

UTI, renal dx, liver dx, tox screen, abd. pain, back pain, blood in urine

Question 19

Urinary Protein

Answer 19

Monitors kidney fuction
Normally NOT present
Dipstick testes, quantification requires 24 hr urine collection
May indicate nephrotic syndrome, multiple myeloma or complication fo DM, glomerylonephritis, amyloidosis.

Question 20

Urinary Glucose

Answer 20

Renal glucose reabsorption threshold=180 ng/dl in PRT
May not be abd. normal elevation after high carb meal
Elevated in DM, pregnancy, renal glycosuria, fanconi syndrome, hereditary defects, increased ICP, nephrotoxic chemicals

Question 21

Urinary Leukocyte esterase

Answer 21

Dipstick screening test for leukocytes
Presence indicates UTI
90% accurate c clean catch

Question 22

Urinary Ketones

Answer 22

End product of fatty acid catabolism
Ex: B-hydroxybutyric acid, acetoacetic acid, acetone
Associated c poorly controlled DM
Used to evaluated Ketoacidosis associated x alcoholism, fasting, starvation, highprotein diet, ispopanol ingestion

Question 23

Urinary Nitrates

Answer 23

Dipstick screen for UTI
Test based on chemical rxn by bacterial reductase (reduces nitrate to nitrite)
50% accurate
Enhances leucocyte esterase sensitivity

Question 24

Urinary castd

Answer 24

Cylindrical structure produced by the kidneys and present in the urine in certain dx processes. Formed via the DCT and collecting ducts of nephrons which pass into the urine
Two types
Cellular and Acellular