Reaction with hemoglobin or related compound:
(1) free hemoglobin from in vivo hemolysis (hemolytic anemia)
(2) free hemoglobin from in vitro hemolysis (poorly preserved or handled specimen)
(3) myoglobin (myoglobinuria)
(4) porphyrins (this also may cause discoloration of the urine)
|
Testing
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Hemoglobinuria
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Myoglobinuria
|
|
serum appearance
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may be pink
|
appears normal
|
|
serum CK
|
usually normal
|
markedly elevated
|
|
serum haptoglobin
|
decreased
|
normal
|
|
serum bilirubin
|
may be elevated
|
usually normal
|
|
hemosiderin in urine sediment
|
may be present with chronic hemolysis
|
usually negative
|
|
urine myoglobin
|
negative
|
present
|
Oxidizing agent causing a false positive reaction on the test strip:
(1) bacterial peroxidases (bacterial cystitis, etc.)
(2) bromide
(3) iodine, including povidone (Betadine)
(4) permanganate
(5) rifampin
(6) phenolphthalein
(7) copper
(8) certain foods (beets, blackberries, rhubarb)
(9) hypochlorite (bleach)
