Bence Jones Protein Detection Methods

Protein electrophoresis is used to identify the presence of Bence Jones protein by showing a distinct peak in the globulin region.

The traditional method uses Amido black stain on a 200-fold concentrated urine sample, whereas newer methods utilize modified Coomassie brilliant blue stain on less concentrated urine.

Bence Jones protein precipitates at temperatures between 40°C and 60°C and redissolves near 100°C.

<p>Alternative methods include immunofixation electrophoresis and immunoassay for free light chains.</p> Signup and view all the answers

<p>Most methods would show positive results in cases of significant Bence Jones proteinuria.</p> Signup and view all the answers

<p>The test detects the pseudoperoxidase activity of hemoglobin or myoglobin that reacts with hydrogen peroxide and chromogen to form an oxidized chromogen and water.</p> Signup and view all the answers

<p>A positive test shows a speckled pattern for low RBC numbers or a uniform color for free hemoglobin or high RBC counts.</p> Signup and view all the answers

<p>Vegetable peroxidase and <em>Escherichia coli</em> peroxidase may cause false positives.</p> Signup and view all the answers

<p>High levels of ascorbic acid and the presence of nitrites can result in false negatives.</p> Signup and view all the answers

<p>Detecting hemoglobin or myoglobin in urine can indicate possible hematuria or muscle damage, respectively.</p> Signup and view all the answers

<p>Hemosiderin is an iron-storage complex formed from the catabolism of hemoglobin by proximal tubular cells in the kidneys after an acute hemolytic episode.</p> Signup and view all the answers

<p>The reagent strip for hemoglobin can be negative because hemosiderin is typically present 2-3 days post-hemolysis, after free hemoglobin has been filtered and cleared.</p> Signup and view all the answers

<p>Hemosiderin can appear in the urine sediment in diseases characterized by true siderosis of kidney parenchyma, such as hemochromatosis.</p> Signup and view all the answers

<p>The presence of hemosiderin in urine indicates a chronic hemolytic state, though its detection is rarely required for diagnosing hemolysis.</p> Signup and view all the answers

<p>Hemosiderin can be found as free yellow-brown granules or located in epithelial cells and occasionally in casts within the urine.</p> Signup and view all the answers

<p>It indicates significant intravascular hemolysis.</p> Signup and view all the answers

<p>It is transported in the blood and prevents free hemoglobin from passing into the urine.</p> Signup and view all the answers

<p>The excess hemoglobin passes through the glomerulus as αβ dimers.</p> Signup and view all the answers

<p>They reabsorb some of the hemoglobin for further processing.</p> Signup and view all the answers

<p>It can cause direct trauma to small blood vessels, leading to hemolysis and hemoglobinuria.</p> Signup and view all the answers

<p>Rhabdomyolysis, which involves the acute destruction of muscle fibers, primarily leads to myoglobinuria.</p> Signup and view all the answers

<p>Free myoglobin is excreted quickly, while the hemoglobin-haptoglobin complex is removed more slowly.</p> Signup and view all the answers

<p>Strenuous exercise, such as marathons, can cause myoglobinuria due to the intense muscle strain leading to muscle fiber damage.</p> Signup and view all the answers

<p>Dermatomyositis and defects in muscle phosphofructokinase are two less common causes of myoglobinuria.</p> Signup and view all the answers

<p>The molecular weight of free myoglobin is 17,000, which is relevant as it affects its rapid excretion in urine.</p> Signup and view all the answers

<p>To detect ketones in urine.</p> Signup and view all the answers

<p>It uses beta-hydroxybutyrate dehydrogenase to detect the acid.</p> Signup and view all the answers

<p>Hematuria refers to blood cells in urine, while hemoglobinuria refers to free hemoglobin in urine.</p> Signup and view all the answers

<p>Hematuria is common, while myoglobinuria is rare.</p> Signup and view all the answers

<p>It can be detected in up to 16% of screening populations using dipstick tests.</p> Signup and view all the answers

<p>Acetone, acetoacetic acid, and beta-hydroxybutyric acid.</p> Signup and view all the answers

<p>Ketones appear in urine when fat reserves are needed for energy.</p> Signup and view all the answers

<p>Ketonuria indicates the presence of ketoacidosis and may signal impending coma.</p> Signup and view all the answers

<p>It helps monitor insulin dosage, detect electrolyte imbalances, and assess excessive carbohydrate loss.</p> Signup and view all the answers

<p>Up to 50 mg of acetoacetic acid per deciliter.</p> Signup and view all the answers

<p>Fanconi's syndrome and Galactosemia.</p> Signup and view all the answers

<p>Reagent strips using sodium nitroprusside measure acetoacetic acid and with glycine also measures acetone.</p> Signup and view all the answers

<p>Pigmented urine and the presence of dyes or phenylketones can lead to false positives.</p> Signup and view all the answers

<p>Bacterial breakdown of acetoacetic acid can lead to false negatives.</p> Signup and view all the answers

<p>They are more susceptible due to insulin management issues often exacerbated by infection or stress.</p> Signup and view all the answers

<p>Membranous nephropathy and IgA nephropathy can cause hematuria, leading to kidney damage and impaired function.</p> Signup and view all the answers

<p>More than 15% of patients showed normal histology.</p> Signup and view all the answers

<p>Trauma can cause hematuria by direct injury to the kidneys or urinary tract, such as from kidney stones.</p> Signup and view all the answers

<p>Giant cell arteritis has been reported to present with hematuria and fever.</p> Signup and view all the answers

<p>Strenuous exercise, such as marathon running, can cause hematuria due to stress on the bladder mucosa.</p> Signup and view all the answers

<p>Glycosuria is the presence of glucose in the urine, which can occur due to various conditions such as burns, infections, fractures, and pregnancy.</p> Signup and view all the answers

<p>During pregnancy, an increased glomerular filtration rate can lead to glycosuria by causing filtered glucose to be inadequately reabsorbed.</p> Signup and view all the answers

<p>Glycosuria without hyperglycemia typically indicates renal tubular dysfunction and reduced glucose reabsorption.</p> Signup and view all the answers

<p>Some medications, such as thiazides and corticosteroids, can lead to glycosuria by interfering with glucose metabolism or reabsorption.</p> Signup and view all the answers

<p>Persistent glycosuria during pregnancy may indicate a risk for gestational diabetes and warrants further medical evaluation.</p> Signup and view all the answers