proteinuria(redirected from Protein in urine)
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an excess of serum proteins in the urine, such as in renal disease, after strenuous exercise, or in dehydration.
accidental proteinuria (adventitious proteinuria) proteinuria due not to a kidney disease but to some other condition such as hemorrhage in the urinary tract; called also false proteinuria.
athletic proteinuria effort proteinuria.
dietetic proteinuria (digestive proteinuria) functional proteinuria produced by the eating of certain foods.
effort proteinuria functional proteinuria occurring as a result of vigorous and prolonged exercise of the lower limbs; called also athletic proteinuria.
false proteinuria adventitious proteinuria.
functional proteinuria any proteinuria that is not due to renal disease, such as the transient proteinuria of pregnancy, effort proteinuria, and orthostatic proteinuria.
glomerular proteinuria the most common kind of proteinuria, being due to glomerular disease and abnormal permeability of the glomerular capillaries to protein.
orthostatic proteinuria a form of functional proteinuria, usually seen between the ages of ten and twenty, that occurs on standing erect and disappears on lying down.
overflow proteinuria that due to hemoglobin, myoglobin, or immunoglobulin loss into the urine due to excessive amounts in the bloodstream, such as in multiple myeloma; it is not usually associated with glomerular or tubular disease.
tubular proteinuria proteinuria due to excretion of proteins of low molecular weight such as immunoglobulins, which normally should be reabsorbed.
1. Presence of urinary protein in amounts exceeding 0.3 g in a 24-hour urine collection or in concentrations more than 1 g per liter (1+ to 2+ by standard turbidometric methods) in a random urine collection on two or more occasions at least 6 hours apart; specimens must be clean, voided midstream, or obtained by catheterization.
2. Synonym(s): albuminuria
[protein + G. ouron, urine]
proteinuria/pro·tein·uria/ (-ūr´e-ah) an excess of serum proteins in the urine, as in renal disease or after strenuous exercise.proteinu´ric
proteinuria(prōt′n-o͝or′ē-ə, -yo͝or′-, prō′tē-no͝or′-, -nyo͝or′-)
The presence of excessive amounts of protein in the urine.
Etymology: Gk, proteios + ouron, urine
the presence in the urine of abnormally large quantities of protein, usually albumin. Healthy adults excrete less than 250 mg of protein per day. Persistent proteinuria is usually a sign of renal disease or renal complications of another disease, such as hypertension or heart failure. However, proteinuria can result from heavy exercise or fever. Also called albuminuria.
proteinuriaNephrology The excretion of excessive (> 5 mg/dL) protein in the urine; normally, about 150 mg/day of protein is lost in the urine,1⁄3 is albumin,1⁄3 is Tamm-Horsfall glycoprotein; the rest is divided among actively secreted proteins–eg, retinol binding proteins, β2-microglobulin, Ig light chains and lysozyme; in absence of disease, large proteins are retained due to their size, while the smaller proteins are actively resorbed; proteinuria is most often caused by kidney disease, due to glomerular defects, and defective renal tubular resorption, and most often detected by screening with reagent strip–dipstick. See Functional proteinuria, Overflow proteinuria.
Severe ≥ 1.0 g/dL, due to glomerulonephritis, nephrotic syndrome, lupus nephritis, amyloidosis
Moderate ≥ 0.2 g/dL, ≤ 1.0 g/dL, due to CHF, drugs, acute infections, myeloma, chemical toxins
Mild 0.05-0.2 g/dL, due to polycystic kidneys, pyelonephritis, renal tubular defects
Glomerular pattern Due to a loss of fixed negative charge on the glomerular capillary wall, allowing albumin and other large (≥ 68 kD) molecules to leak into Bowman's space–eg, in glomerulonephritis and nephrotic syndrome Lab ↓ albumin, antithrombin, transferrin, prealbumin, α1-acid glycoprotein, α1-antitrypsin
Hemodynamic pattern Due to rheostatic changes in the body, causing a loss of 20 to 68 kD molecules, seen in transient proteinuria, CHF, fever, seizures, excess exercise.
Overflow pattern Due to tissue/cell destruction that overwhelms renal capacity to excrete certain proteins–eg, Bence-Jones proteinuria and myoglobinuria
Tubular pattern Due to renal tubular dysfunction with loss of normally filtered low molecular weight (≤ 40 kD) molecules Lab ↓ β2-microglobulin and lysozyme–eg, Fanconi syndrome, Wilson's disease, interstitial nephritis, antibiotic-induced injury and heavy metal intoxication
1. Presence of urinary protein in concentrations greater than 0.3 g in a 24-hour urine collection or in concentrations greater than 1 g/L in a random urine collection on two or more occasions at least 6 hours apart; specimens must be clean-voided midstream (i.e., clean catch) or obtained by catheterization.
2. Synonym(s): albuminuria.
[protein + G. ouron, urine]
proteinuriaThe passage of more than minimal amounts of protein in the urine. This usually indicates kidney disease, such as GLOMERULONEPHRITIS or the NEPHROTIC SYNDROME, but may also occur in MYELOMATOSIS or other conditions in which the amount of protein in the blood is excessive.
The presence of protein in the urine exceeding normal levels.
proteinuria; albuminuria the presence of protein (albumin) in urine due to renal dysfunction, e.g. hypertension, renal infection; early-stage renal failure (characteristic of diabetic nephropathy)
Presence of urinary protein in amounts exceeding 0.3 g in a 24-hour urine collection or in concentrations more than 1 g per liter (1+ to 2+ by standard turbidometric methods) in a random urine collection on two or more occasions at least 6 hours apart; specimens must be clean, voided midstream, or obtained by catheterization.
[protein + G. ouron, urine]
n the presence of protein in the urine. It is an indication of kidney disease.
n (postural proteinuria) a type that occurs during daily activities but does not occur when the individual is recumbent.
n See proteinuria, transient.
n See proteinuria, orthostatic.
n (physiologic proteinuria) a type that occurs in normal persons after a high-protein meal, violent exercise, severe emotional stress, or syncope. It may occur after an epileptic seizure or during pregnancy. It disappears after the cause subsides.
an excess of serum proteins in the urine; an important indicator of renal disease. It is a constant finding in glomerulonephritis, renal infarction, amyloidosis and nephrosis, but is also common in congestive heart failure and renal ischemia of all kinds. The significance of proteinuria as an indicator of renal disease is greatly enhanced by the presence of renal casts in the urine.
Bence Jones proteinuria
see bence jones protein.
occurs transiently during the period of intestinal absorption of proteins, some of which are small enough to pass the glomerular membrane.