Microalbuminuria occurs when the kidney leaks small amounts of albumin into the urine – in other words, when there is an abnormally high permeability for albumin in the renal glomerulus.
Microalbuminuria is probably a misnomer. It is not a “small” albumin molecule found in the urine, but simply albumin present in low amounts, below the level of detection of the standard office multi-test urine dipstick.
Blood contains cells and proteins that we need, as well as waste products that our body needs to get rid of. Blood is filtered by the kidneys and waste products are removed from the body via the urine. Usually, cells and proteins stay in the blood, but sometimes a small amount of protein is lost into the urine along with other waste products.
Microalbuminuria is when the level of the protein albumin in urine is always slightly raised. Microalbuminuria is defined as 30 to 300mg of albumin being lost in the urine per day. This is different from proteinuria, which is when the levels of protein in urine are higher than 300mg a day.
CAUSES OF MICROALBUMINURIA:
The development of Microalbuminuria has been linked to diabetes. Other than diabetes, risk factors for developing Microalbuminuria include:
High blood pressure
A family history of diabetic kidney disease
DIAGNOSIS OF MICROALBUMINURIA:
Normally, most protein stays in the body, and little or no protein appears in the urine. If albumin is detected in the urine, it signifies that the kidneys may be damaged or not working properly. Increased levels of albumin may occur with:
Certain immune disorders
High blood pressure
Some lipid problems
The Microalbuminuria Test looks for small quantities of a protein called albumin in a urine sample. Only a small sample of urine needs to be collected. Because the amount of water in urine can vary, it can affect the concentration of albumin. For this reason, the amount of creatinine is also measured. The result is reported as the ratio of albumin to creatinine. This is termed the albumin/creatinine ratio (ACR) and Microalbuminuria is defined as:
ACR greater than or equal to 3.5 mg/mmol in female.
ACR greater than or equal to 2.5 mg/mmol in male.
Or an ACR between 30 & 300 µg albumin/mg creatinine.
The ratio of albumin to creatinine is usually used to classify diabetic nephropathy. A ratio less than 30 micrograms per milligram is normal.
A ratio of 30-299 in two different 24-hour urine samples is considered Microalbuminuria.
A ratio of more than 300 mg is considered Macroalbuminuria.
The American Diabetes Association recommends that people with diabetes receive a Microalbuminuria urine test every year (after 5 years of having the disease in people with type 1 diabetes, and at the time of diagnosis in people with type 2 diabetes).
In type 2 diabetes, having Microalbuminuria is a powerful message that you have an increased risk of heart disease. Microalbuminuria is the strongest independent risk factor of cardiovascular disease. Screening identifies an increased risk of proliferative retinopathy.
Development of Microalbuminuria is closely linked to long term blood sugar control. This risk is increased by:
Duration of diabetes
High blood pressure
Diet and exercise play a key role in controlling blood sugar levels and reducing your weight, blood pressure and cholesterol levels, in turn preventing any further kidney damage. Steps may include:
Exercising regularly, if possible for 30 minutes a day
Eating at least five portions of fruit and vegetables a day
Increasing the amount of starchy carbohydrates in your diet
Choosing to eat carbohydrates that release energy slowly such as porridge oats, brown rice and pasta, lentils and beans and avoiding those that release energy quickly such as white bread and white rice.
Reducing the amount of sugar, fat and salt in your diet
Cutting down on alcohol
Monitoring and controlling your blood sugar levels if you have diabetes
Limitng the amount of foods containing high levels of protein, sodium, potassium or phosphate
The following measures are advisable in diabetes patients:
Tighten up your blood sugar control.
Blood pressure lowering if high
Lipid lowering treatment
Presence of Microalbuminuria signifies:
Blood vessels involved in filtering waste products in kidneys are damaged.
First sign of kidney damage or kidney disease.
Sign of more widespread damage to blood vessels, including those of heart.
Sign of an increased risk of heart disease, particularly in type 2 diabetes.
An indicator of subclinical cardiovascular disease.
Marker of vascular endothelial dysfunction.
An important prognostic marker for kidney disease, especially in diabetes mellitus & in hypertension.
Increasing Microalbuminuria during the first 48 hours after admission to an intensive care unit predicts elevated risk for acute respiratory failure , multiple organ failure and overall mortality.
A risk factor for venous thrombo embolism.
Healthy people may exceed normal levels after strenuous exercise or with dehydration.
THERAPEUTIC HINTS FOR ALBUMINURIA
Urine suppressed or scanty, high colored, fetid, containing albumen, blood corpuscles, uriniferous casts & epithelium.
Fatty degeneration of kidneys with haematuria & epithelial casts in urine.
Indicated in primary cases of tubal nephritis. Urine highly albuminous with waxy & fatty casts.
Albuminuria from cardiac disturbances & periodical effusions, as it reduces the amount of albumen in the urine.
Indicated in interstitial nephritis with contracted kidneys. Renal troubles secondary to cardiac affections, causing a decided albuminous crasis. At first the urine is increased in quantity, later it becomes scanty & albuminous.
Albuminuria depending on nervous disturbance, as from over work, gradually causing renal disorganizations.
Urine of dark, bloody appearance & largely supplied with albumen.
Urine almost dark brown, darker & more scanty than usual.
Great sensitiveness to pressure in renal region. Must urinate every hour & urine full of albumen.
Albuminuria following Eruptive diseases, especially variola.
Albuminuria as sequelae of pericarditis.
Indicated in Post-Scarlatinal Nephritis & early stages, especially when occurring from blows on the loins, or sudden change of temperature & when there is more renal desquamation than blood. Urine contains an excessive quantity of swollen epithelial cells.
Post – Scarlatinal Nephritis with much exhaustion.
Albuminuria as a result of intercurrent Pneumonia. Urine red & turbid.
Indicated in Acute desquamative nephritis with Pulmonary congestion.
Urine as black as ink, containing blood, & loaded with albumen & tube-casts, smoky in appearance. Patient cannot stand up straight or lie down with stretched out legs without causing pain in renal region.
Urine dark, smoky from admixture of fluid blood with renal congestion.
Urine containing albumen & renal elements with uremic convulsions.
Post – Scarlatinal nephritis. Granular degeneration of the kidneys. Scanty urination, urine albuminous, thick, turbid, blackish. Urinary solids absolutely diminished. Contracted kidney & uremic poisoning.
Cirrhotic kidney with Albuminuria. Urine high colored, burning while passing, with red sediment & muddy, reddish – yellow slime.
Post – Scarlatinal or Post – diphtheritic nephritis. Black urine with a black cloud near the bottom of the chamber or a coffee – ground sediment.
Urine, profuse, clear, light colored, albuminous with diabetes.
Post – Scarlatinal nephritis. Urine dark red, hot, bloody, burning, or pale, with flocculent, muddy looking sediment.
Nephritis with a syphilitic background. Urine loaded with epithelial casts & albumen.
Albuminuria as a result of heart complication. Urine scanty, albuminous with fibrinous casts & epithelial cells.
Nephritis after excessive use of alcohol. Urine dark, turbid or black in spots with full of albumen.
Early stages of nephritis, especially when caused by abuse of alcoholic drinks, by cold or by obstructed portal circulation. Scanty bloody urine with effusion of fibrin or fat globules in the urine, or profuse secretion of pale, albuminous urine.
Urine contains much phosphate, fibrinous casts & epithelial cells, fatty corpuscles, rarely carbonate of ammonia with albumen.
Kidney present with great structural changes, granular & fatty degenerations, destruction of epithelium & finally atrophy. Urine highly albuminous.
Granular kidney with a urine of low specific gravity, pale, containing albumen, tube casts, epithelial cells, blood & pus corpuscles.
Post – Scarlatinal nephritis. Urine pale or bloody, urinary deposits looking like cheese.
Indicated in early stages, when blood & albumen abound more than casts & epithelium. Urine much diminished in quantity & highly charged with decomposed blood.