Microalbuminuria

What sample is needed for Microalbuminuria?

1. The sample is urine.
2. It is better to do three random samples for a week.
3. The urine sample is stable at room temperature for up to 2 days and at 8 °C for up to 14 days.

What are the indications for Microalbuminuria?

1. This is advised in a diabetic patient to rule out diabetic nephropathy; even routine urine tests are negative.
2. High-risk patients should be tested within a 3 to 6-month period.
3. Check-in the case of hypertensive patients.

What are the precautions for microalbuminuria?

1. Avoid urine after exercise.
2. Avoid prolonged upright posture.
3. Avoid in case of hematuria.
4. Avoid blood-contaminated urine.
5. Avoid in case of genitourinary tract infection.
6. Avoid in case of congestive heart failure.
7. Avoid in case of uncontrolled hyperglycemia or hypertension.
8. Avoid in test tubes where albumin is attached.

What are the factors for False-positive microalbuminuria?

1. It can get false positive results when the urine pH is≥8.0.
2. When the temperature is >77 °F.
3. When Tamm-Horsfall protein is present in the urine.

How will you define microalbuminuria?

1. Microalbumin is a misnomer. This does not refer to any different form of albumin; instead, a small amount of albumin is excreted in the urine.
2. Microalbuminuria is defined as persistent proteinuria below the detection limit of routine reagent strips but greater than normal.
3. This is defined as the excretion of 30 to 150  µg/min protein in the urine and is not detected by dipsticks but can be measured by sensitive methods.
4. Microalbuminuria is predictive of diabetic nephropathy.

How will you discuss the pathophysiology of Diabetic microalbuminuria?

1. Albumin excretion of 20 to 200 µg/minute (30 to 300 mg/24 hours) detected 2/3 determinations done in the last 6 months.
2. Microalbuminuria may be found in non-diabetic hypertensive patients.
3. The subclinical state of selectively elevated albumin excretion rate is called microalbuminuria.

4. Normally, the glomeruli excrete a small amount, which the tubules reabsorb.

5. When the disease increases, the albumin excreted by the glomeruli is more than reabsorbed by the tubule, leading to microalbuminuria, which is not detected by ordinary methods.
6. There are structural changes in the glomeruli leading to increased glomerular permeability.
7. Increased glomerular permeability increases urinary exertion of proteins like albumin and IgG.
   3. Albumin remains normal in the first 5 years of diabetes mellitus type 1.
8. This urinary albumin excretion precedes and is highly indicative of diabetic nephropathy and is called microalbuminuria.
9. Early detection of microalbumin may predict end-stage renal nephropathies in Diabetes type 1 (IDDM) patients.
10. This test is useful for diagnosing Angiopathic changes in diabetic patients before gross proteinuria is seen.
11. Evidence suggests that lowering blood pressure and controlling hyperglycemia will alter the disease’s course and prevent irreversible nephropathy.

What is the significance of the Microalbuminuria?

1. It is the first sign of diabetes complications (Risk factor predictor):
2. Diabetic nephropathy.
3. Cardiovascular diseases.
4. Myocardial infarction.
5. Hypertension.
6. Stroke.
7. Kidney failure.
8. Death.
9. Diabetic patients with microalbuminuria have 5 to 10 times more chances for cardiovascular mortality, retinopathy, and end-stage kidney.
10. The presence of microalbuminuria in nondiabetic patients is an indicator of lower life expectancy because of hypertension and cardiovascular disease risk.
11. Nondiabetic nephropathies may show microalbuminuria.
12. Microalbuminuria indicates early stage and risk factors for cardiovascular or renal disease.

What are the recommendations for microalbuminuria in diabetic patients?

1. Diabetic patients should have an annual checkup of microalbuminuria (3 to 6 months).
2. if 2 out of 3 measurements are >20 mg/L, start the treatment (intervention).

What are the causes of Microalbuminuria?

1. Diabetes mellitus.
2. Myoglobinuria.
3. Nephrotoxic drugs.
4. Bence-Jones proteinuria.
5. Hemoglobinuria.
6. Any kind of Nephropathy.
7. Hypertension.
8. Myocardial infarction.
9. Atherosclerosis ( Generalized vascular disease ).
10. Lipid abnormalities.
11. Pre-eclampsia.

What are the complications of microalbuminuria?

1. It shows poor glycemic control.
2. High blood pressure.
3. Development of advanced retinopathy.
4. Development of neuropathy.
5. Advanced nephropathy.
6. Ultimately, renal failure.
7. Increased vascular damage.
8. Risk for cardiovascular disease.

What is the interpretation of microalbuminuria?

1. Albumin/creatinine ratio >30 mg/g predicts an overnight excretion rate of 30 µg/minute.
2. Albuminuria <0.3 g/day will be detected only by sensitive methods like nephelometry or electrophoresis.

What is normal Albumin in the urine?

Source 1

• Albumin in urine <30 mg/24 hours
• Or <20 mg/day.
• Or <20 mg/L (urine collected in 10 hours).

Source 2 

• 0.2 to 1.9 mg/dL

 Abnormal value 

• Albumin >30 mg/24 hours.
• Or >20 mg/L (in 10 hours).

Limits with various dipsticks:

1. Albusure 2 to 3 mg/dl
2. Micral 1.5 to 2 mg/dl
3. Micro-Burnintest 4 to 8 mg/dl

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