Synonym/Acronym
Alb, A/G ratio, AGR.
Rationale
A multipurpose study used to assess liver or kidney function and nutritional status.
A small group of studies in this manual have been identified as Core Lab Studies. The designation is meant to assist the reader in sorting the basic “always need to know” laboratory studies from the hundreds of other valuable studies found in the manual—a way to begin putting it all together.
Normal, abnormal, or various combinations of core lab study results can indicate that all is well, reveal a problem that requires further investigation with additional testing, signal a positive response to treatment, or suggest that the health status is as expected for the associated situation and time frame.
Albumin (Alb) is included in the liver function test panel (LFTs) and in the comprehensive metabolic panel (CMP). LFTs are used to identify liver disease, assess severity of injury, or monitor disease process and response to treatment. CMPs are used as a general health screen to identify or monitor conditions such as bone disease, diabetes, electrolyte imbalance, hypertension, kidney disease, liver disease, or malnutrition.
Patient Preparation
There are no food, fluid, activity, or medication restrictions unless by medical direction.
Normal Findings
(Method: Spectrophotometry).
| Age | Conventional Units | SI Units (Conventional Units × 10) |
|---|
| Newborn | 2.6–3.6 g/dL | 26–36 g/L | | Child | 3.4–5.2 g/dL | 34–42 g/L | | Adult | 3.7–5.1 g/dL | 37–51 g/L | | Pregnant female (st trimester) | 3.1–5.1 g/dL | 31–51 g/L | | Pregnant female (2nd trimester) | 2.6–4.5 g/dL | 26–45 g/L | | Pregnant female (3rd trimester) | 2.3–4.2 g/dL | 23–42 g/L | | Older Adult | 3.2–4.6 g/dL | 32–46 g/L | | Greater than 90 yr | 2.9–4.5 g/dL | 29–45 g/L |
Normally, the A/G ratio is greater than 1. Albumin levels are affected by posture. Results from specimens collected in an upright posture are higher than results from specimens collected in a supine position. |
Study type: Blood collected in a gold-, red-, red/gray-, or green-top [heparin] tube; related body system: Digestive and Urinary systems.
Albumin and globulins are the two main types of total protein (TP) in the body. Albumin, alpha globulins, and beta globulins are synthesized in the liver; gamma globulins are made by plasma cells (a type of WBC cell differentiated from B cell lymphocytes). Albumin comprises about 60% of the body’s total protein and is the main transport protein in the body for hormones, therapeutic drugs, calcium, magnesium, heme, and waste products such as bilirubin. Albumin also significantly affects plasma oncotic pressure, which regulates the distribution of body fluid between blood vessels, tissues, and cells. 30% to 40% of the body’s albumin is located in the intravascular compartment; the remainder is located in the interstitial spaces of the extravascular compartment (mostly found in muscles and skin). Small quantities of albumin are also present in bile, gastric juices, sweat, and tears.
Albumin does not diffuse freely through intact vascular endothelium. Hence, it is the major protein providing the critical colloid osmotic or oncotic pressure that regulates passage of water and diffusable solutes through the capillaries. Albumin accounts for 70% of the colloid osmotic pressure. It exerts a greater osmotic force than can be accounted for solely on the basis of the number of molecules dissolved in the plasma, and for this reason it cannot be completely replaced by inert substances such as dextran. The reason is that albumin has a negative charge at normal blood pH and attracts and retains cations, especially Na+ in the vascular compartment. This is called the Gibbs–Donnan effect. Albumin also binds a small number of Cl- ions that increase its negative charge and ability to retain Na+ ions inside the capillaries. This enhanced osmotic force causes the colloid osmotic pressure to be 50% greater than it would be by protein concentration alone. Also, albumin values naturally fall in pregnancy, especially in the third trimester, because of the increase in plasma volume. The liver produces 9 to 12 grams/day of this complex substance; a molecule of serum albumin looks like a large bunch of grapes. About 60% of albumin is located in the extravascular space. Because of its strong negative charge, albumin is water soluble. It has a circulating life span of 12 to 20 days and a turnover rate of about 15 grams/day. Reserve albumin isn’t stored. Albumin doesn’t appear to decrease related to starvation, but catabolism slows due to redistribution. One of albumin’s functions is to maintain colloid osmotic pressure, which keeps fluid moving throughout the body. Albumin also helps metabolize and detoxify substances (such as bilirubin, metals, ions, enzymes, amino acids, hormones, free fatty acids, drugs, and phospholipids) and is a free-radical scavenger.
Low levels of albumin may be the result of either inadequate intake, inadequate production, or excessive loss. Albumin levels are more useful as an indicator of chronic deficiency than of short-term deficiency; circulating half life is 12 to 20 days. Hypoalbuminemia or low serum albumin can stem from many causes and may be a useful predictor of mortality. Normally, albumin is not excreted in urine. However, in cases of kidney injury or disease, some albumin may be lost due to decreased kidney function, as seen in nephrotic syndrome, and in pregnant women with pre-eclampsia and eclampsia.
The A/G ratio is useful in the evaluation of liver and kidney disease. The ratio is calculated using the following formula: 
albumin/(total protein - albumin),where globulin is the difference between the total protein value and the albumin value. For example, with a total protein of 7 g/dL and albumin of 4 g/dL, the A/G ratio is calculated as 4/(7 - 4) or 4/3 = 1.33.
A low A/G ratio may reflect decreased synthesis of albumin e.g., related to kidney or liver disease, extreme loss of circulating albumin e.g., related to severe burns, or increased synthesis of globulins e.g., related to chronic inflammatory diseases, monoclonal gammopathies such as multiple myeloma.
A high A/G ratio may reflect decreased synthesis of immunoglobulins e.g., related to genetic deficiencies such as analbuminemia, some leukemias, some cases of hypothyroidism.
| Examples of Possible Patterns Between Alb Levels and Other Core LFT Levels in Specific Hepatic Conditions |
|---|
| Diagnosis | Alb Level (Other Core LFTs) |
|---|
| Cholestasis | ↓Normal to Mild (ALP ↑↑↑, ALT ↑, AST ↑, TBil ↑) | | Cirrhosis | ↓Normal to Mild (ALP ↑ to ↑↑, ALT ↑ to ↑↑, AST ↑↑↑, TBil ↑) | | Hepatitis, viral, acute | ↓Normal to Mild, initially (ALP ↑ to ↑↑, ALT ↑↑↑, AST ↑↑↑, TBil ↑ to ↑↑) | | Hepatitis, toxin or drug related | ↓Normal to Mild, initially (ALP ↑ to ↑↑, ALT ↑↑↑, AST ↑↑↑, TBil ↑↑) | | Infarction, acute necrosis of the liver, or cancer | ↓Normal to Mild, initially (ALP ↑ to ↑↑, ALT ↑↑↑, AST ↑↑ to ↑↑↑, TBil ↑↑) | | Jaundice, hepatic origin | ↓Normal to Mild (ALT ↑↑ with ALT rising before AST and TBil, AST ↑↑, TBil ↑ to ↑↑) |
N = Normal, ↓ Normal to Mild decrease, ↑ Normal to Mild increase, ↑ to ↑↑ Normal to Mild or Moderate, ↑↑ Mild to Moderate, ↑↑↑ Marked. Study levels will vary with degree and progression of liver damage. |
Factors That May Alter the Results of the Study
- Drugs and other substances that may increase albumin levels include carbamazepine, furosemide, phenobarbital, and prednisolone.
- Drugs and other substances that may decrease albumin levels include acetaminophen (poisoning), amiodarone, asparaginase, dextran, estrogens, ibuprofen, methotrexate, methyldopa, niacin, nitrofurantoin, oral contraceptives, phenytoin, prednisone, and valproic acid.
Other Considerations
- Availability of administered drugs is affected by variations in albumin levels.
Increased In
Any condition that results in a decrease of plasma water (e.g., dehydration); look for increase in Hgb and Hct. Decreases in the volume of intravascular liquid automatically result in concentration of the components present in the remaining liquid, as reflected by an elevated albumin level.
Decreased In
- Insufficient intake:
- Malabsorption(related to lack of amino acids available for protein synthesis)
- Malnutrition (related to insufficient dietary source of amino acids required for protein synthesis)
- Decreased synthesis by the liver:
- Acute and chronic liver disease (e.g., substance use disorder [alcohol], cirrhosis, hepatitis) (evidenced by a decrease in normal liver function; the liver is the body’s site of protein synthesis)
- Genetic analbuminemia(related to genetic inability of the liver to synthesize albumin)
- Inflammation and chronic diseases result in production of acute-phase reactant and other globulin proteins; the increase in globulins causes a corresponding relative decrease in albumin:
- Amyloidosis
- Bacterial infections
- Monoclonal gammopathies (e.g., multiple myeloma, Waldenström macroglobulinemia)
- Parasitic infestations
- Peptic ulcer
- Pregnancy (related to fluid retention, dietary insufficiency, increased demands of growing fetus)
- Prolonged immobilization
- Rheumatic diseases
- Severe skin disease
- Tumor
- Increased loss over body surface:
- Burns (evidenced by loss of interstitial fluid albumin)
- Enteropathies (e.g., gluten sensitivity, Crohn disease, ulcerative colitis, Whipple disease) (evidenced by sensitivity to ingested substances or related to inadequate absorption from intestinal loss)
- Fistula (gastrointestinal or lymphatic) (related to loss of sequestered albumin from general circulation)
- Hemorrhage(related to fluid loss)
- Kidney disease (related to loss from damaged renal tubules)
- Pre-eclampsia (evidenced by excessive renal loss)
- Rapid hydration or overhydration (evidenced by dilution effect)
- Repeated thoracentesis or paracentesis (related to removal of albumin in accumulated third-space fluid)
- Increased catabolism:
- Cushing disease(related to excessive cortisol induced protein metabolism)
- Heart failure (evidenced by dilution effect)
- Thyroid dysfunction (related to overproduction of albumin-binding thyroid hormones)
- Increased blood volume (hypervolemia):
- Pre-eclampsia (related to fluid retention)
- Pregnancy (evidenced by increased circulatory volume from placenta and fetus)
Potential Nursing Problems: Assessment & Nursing Diagnosis
| Problems | Signs and Symptoms |
|---|
| Body image (related to increased androgen production, altered protein metabolism, altered fat distribution, edema) | Abnormal male pattern hair growth in women, face, chest, back (hirsutism); muscle wasting; fragile capillaries; ecchymosis; osteoporosis; purple striae; slender limbs from altered protein metabolism; trunk obesity; moon face; cervicodorsal fat resulting in buffalo hump back | | Fluid volume (deficit-related to gastrointestinal bleeding, vomiting, deficient fluid intake) | Tachycardia; hypotension with orthostaic changes; dry mucous membranes; cool, clammy skin; capillary refill greater than 3 seconds; thirst; decreased skin turgor; dizziness; decreased urinary output; altered level of consciousness | | Fluid volume (excess—fluid volume related to increased protal venous pressure, imbalanced aldosterone; hypoalbuminemia; inadequate protein intake, low serum oncotic pressure) | Weight gain; increasing abdominal girth; abdomen is taut and dull to percussion; jugular vein distention; altered breathing patterns, shortness of breath, crackles; increasing central venous pressure; dehydration; edema | | Nutrition(insufficient—nutrition related to the inability to ingest or digest food, psychological factors [anorexia, bulimia], inability to absorb nutrients, inadequate dietary intake, inadequate financial resources) | Weight loss regardless of sufficient intake, ideal body weight is greater than 20% less of ideal weight, intake is less than the recommended dietary allowance, excessive hair loss, weakness, lack of interest in food or eating, pale mucous membranes, mouth sores, fatigue; listlessness | | Skin (related to major or minor burn) | Pain or absence of pain, skin that is blistering or weeping, red or blanching skin, skin color changes of brown to black, skin loss; skin has a leathery appearance |
|
Before the Study: Planning and Implementation
Teaching the Patient What to Expect
- Discuss how this test can assist with evaluation of liver and kidney function as well as chronic disease and malnutrition.
- Explain that a blood sample is needed for the test.
Potential Nursing Actions
- Assess for signs of edema or ascites; measure abdominal girth and trend.
- Assess current diet for nutritional balance.
Safety Considerations
- To prevent development of toxic drug concentrations, patients receiving therapeutic drug treatments should have their drug levels monitored when levels of the transport protein albumin are decreased.
After the Study: Implementation & Evaluation Potential Nursing Actions
Treatment Considerations
- Monitor and trend Alb. Compare with LFTs (ALT, ALP, AST, TBil, DBil, TP) or other related studies to track the course of disease and response to treatment. If liver function is significantly damaged, PT will be prolonged and INR increased.
Body Image
- Provide referrals to culturally appropriate support groups.
- Assess for visual changes related to cortisol excess.
- Assess for positive coping strategies related to altered physical appearance.
- Encourage expression of feelings associated with physical changes.
- Discuss how altered appearance may resolve with return to normal hormone levels.
Fluid Volume, Deficit
- Facilitate management of fluid volume deficit.
- Monitor and trend B/P for orthostatic hypotension, elevated heart rate.
- Monitor for decreasing urine output.
- Monitor and trend Hgb and Hct.
- Encourage reporting any dizziness, shortness of breath.
- Administer ordered blood, fluids, volume expanders.
- Encourage oral fluids.
- Provide education on disease process, necessary lifestyle changes, reportable symptoms.
Fluid Volume, Excess
- Facilitate management of fluid volume excess.
- Assess for signs of portal hypertension and gastrointestinal bleed.
- Assess for ascites in the peritoneal cavity as excess fluid may impinge on both respiratory and digestive function.
- Measure abdominal girth at the same place each day.
- Access for abdominal dullness with percussion.
- Monitor both fluid intake and urinary output.
- Enforce ordered fluid limit.
- Administer prescribed diuretics (spironolactone); facilitate paracentesis as needed; abdominal binder; facilitate use of incentive spirometer.
Nutrition
- Measure weight daily. Calorie count. Counseling. Dietary consult.
- Assess current eating patterns, and attitudes toward food.
- Monitor and trend laboratory values associated with nutrition, serum albumin, transferrin, RBC, WBC, electrolytes.
- Facilitate a pleasant eating environment; consider championship during meals to enhance appetite.
- Provide culturally appropriate foods from home.
- Discourage caffeinated or carbonated drinks as they may sate the appetite.
- Administer ordered nutrition supplements.
- Facilitate speech therapy consult if impaired swallowing is noted.
Skin
- Assess percentage of body surface that is burned.
- Assess for the extent and depth of wounds, superficial (pink, painful, non-blistered skin), partial-thickness (red or pink blistered painful skin), full-thickness (non-painful from nerve destruction, skin is charred, gray, white, or not intact).
- Assess pain level and medicate as ordered.
- Clean skin with an antimicrobial soap.
- Facilitate hydrotherapy to remove slough, exudate, and eschar.
- Apply ordered topical bacteriostatics such as bacitracin, silver sulfadiazine.
- Elevate extremities to decrease swelling.
- Maintain correct anatomical position to decrease contracture risk.
Nutritional Considerations
- Dietary recommendations may be indicated and will vary depending on the condition and its severity.
- Monitor and trend laboratory values that evaluate nutritional status (Alb, TP, K+), and collaborate with HCP on replacement strategies.
- Consider small frequent meals; administer ordered antiemetics.
Clinical Judgement
- Consider how an altered albumin significantly affects body fluid homeostasis, and why.
Follow-Up and Desired Outcomes
- Acknowledges the importance of a balanced fluid intake to maintain personal health.
- Seeks psychological counseling to address, fear, anxiety, or depression associated with diagnosis and prognosis.