Synonym/Acronym
alk Phos, ALP fractionation, heat-stable ALP.
Rationale
Alkaline phosphatase (ALP) is used to assist in the diagnosis of liver and bone disease.
This Core Lab Study 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, 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 for total alkaline phosphatase, inhibition/electrophoresis for fractionation.
| Age/Gender | Total ALP Conventional and SI Units | Bone Fraction Conventional and SI Units | Liver Fraction Conventional and SI Units |
|---|
| Newborn | | | |
| Male | 75–375 units/L | N/A | N/A |
| Female | 65–350 units/L | N/A | N/A |
| 1–8 yr | | | |
| Male | 70–364 units/L | 50–319 units/L | Less than 8–76 units/L |
| Female | 73–378 units/L | 56–300 units/L | Less than 8–53 units/L |
| 9–12 yr | | | |
| Male | 112–476 units/L | 78–339 units/L | Less than 8–81 units/L |
| Female | 98–448 units/L | 78–353 units/L | Less than 8–62 units/L |
| 13–14 yr | | | |
| Male | 112–476 units/L | 78–389 units/L | Less than 8–48 units/L |
| Female | 56–350 units/L | 28–252 units/L | Less than 8–50 units/L |
| 15 yr | | | |
| Male | 70–378 units/L | 48–311 units/L | Less than 8–39 units/L |
| Female | 42–168 units/L | 20–115 units/L | Less than 8–53 units/L |
| 16 yr | | | |
| Male | 70–378 units/L | 48–311 units/L | Less than 8–39 units/L |
| Female | 28–126 units/L | 14–87 units/L | Less than 8–50 units/L |
| 17 yr | | | |
| Male | 56–238 units/L | 34–190 units/L | Less than 8–39 units/L |
| Female | 28–126 units/L | 17–84 units/L | Less than 8–53 units/L |
| Adult | | | |
| Male | 35–142 units/L | 11–73 units/L | 0–93 units/L |
| Female | 25–125 units/L | 11–73 units/L | 0–93 units/L |
(Study type: Blood collected in a gold-, red-, red/gray-, or green-top [heparin] tube; related body system: Digestive and musculoskeletal systems.)
ALP is an enzyme found in the liver; in Kupffer cells lining the biliary tract; and in bones, intestines, and placenta. Other sources of ALP include the proximal tubules of the kidneys, pulmonary alveolar cells, germ cells, vascular bed, lactating mammary glands, and granulocytes of circulating blood. ALP is referred to as alkaline because it functions optimally at pH 9.
There are a number of isoenzymes of ALP. Elevations in two main ALP isoenzymes, however, are of clinical significance and are used to identify the source of increased ALP levels: ALP1 of liver origin and ALP2 of bone origin. Measurement of bone-specific ALP is also used as an indicator of increased bone turnover and estrogen deficiency in postmenopausal women.
ALP is most often used in combination with other liver enzymes to assist in the diagnosis of liver disease. Together, increases in levels of ALP and the liver enzyme gamma glutamyl transferase (GGT) help differentiate cholestasis from other liver diseases. Isolated increases in ALP levels are usually related to nonhepatic conditions such as pregnancy or diseases of the bone, kidneys (chronic), lymph nodes.
| Examples of Possible Patterns Between ALP Levels and Other Core LFT Levels in Specific Hepatic Conditions |
|---|
| Diagnosis | ALP Level (Other Core LFTs) |
|---|
| Cholestasis | Marked ↑↑↑ (Alb ↓, ALT ↑, AST ↑, TBil ↑). Marked elevations of ALP and GGT are indicative of cholestasis. |
| Cirrhosis | Normal to Mild or Moderate ↑ to ↑↑ (Alb ↓, ALT ↑ to ↑↑, AST ↑↑↑, TBil ↑) |
| Hepatitis, viral, acute | Normal to Mild or Moderate ↑ to ↑↑ (Alb ↓, ALT ↑↑↑, AST ↑↑↑, TBil ↑ to ↑↑) |
| Hepatitis, toxin or drug related | Normal to Mild or Moderate ↑ to ↑↑ (Alb ↓, ALT ↑↑↑, AST ↑↑↑, TBil ↑↑) |
| Infarction, acute necrosis of the liver, or cancer | Normal to Mild or Moderate ↑ to ↑↑ (Alb ↓, ALT ↑↑↑, AST ↑↑ to ↑↑↑, TBil ↑↑) |
| Jaundice, hepatic origin | Normal to Mild or Moderate ↑ to ↑↑ in obstructive hepatic jaundice (Alb ↓, 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.
Increased In
Related to release of alkaline phosphatase from damaged bone, biliary tract, and liver cells.
- Liver disease:
- Biliary atresia
- Biliary obstruction (especially cholestasis), intra- or extra- (acute cholecystitis [e.g., gallstones], cholelithiasis, intrahepatic cholestasis of pregnancy, primary biliary cholangitis)
- Cancer
- Cirrhosis
- Diabetes (diabetic hepatic lipidosis)
- Granulomatous or infiltrative liver diseases (sarcoidosis, amyloidosis, tuberculosis)
- Hepatitis
- Infectious mononucleosis
- Bone disease:
- Healing fractures
- Metabolic bone diseases (rickets, osteomalacia)
- Osteogenic sarcoma
- Osteoporosis
- Paget disease (osteitis deformans)
- Primary lymphoma of bone
- Sarcoidosis
- Tumors (metastatic) (especially bone)
- Other conditions:
- Advanced pregnancy (related to additional sources: placental tissue and new fetal bone growth; marked decline is seen with placental insufficiency and imminent fetal demise)
- Cancer of the breast, colon, gallbladder, lung, or pancreas
- Chronic obstructive pulmonary disease (COPD)
- Familial hyperphosphatemia
- Heart failure
- HELLP syndrome of pregnancy (hemolysis, elevated liver enzymes, low platelet count)
- Hyperparathyroidism
- Perforated bowel
- Pneumonia
- Pulmonary and myocardial infarctions
- Pulmonary embolism
- Ulcerative colitis
Decreased In
- Anemia (severe)
- Celiac disease
- Folic acid deficiency
- HIV1 infection
- Hypervitaminosis D
- Hypophosphatasia (related to insufficient phosphorus source for ALP production; inherited and rare)
- Hypothyroidism (characteristic in infantile and juvenile cases)
- Nutritional deficiency of zinc or magnesium
- Pernicious anemia
- Scurvy (related to vitamin C deficiency)
- Whipple disease
- Zollinger-Ellison syndrome
Potential Problems: Assessment & Nursing Diagnosis/Analysis
| Problems | Signs and Symptoms |
|---|
| Confusion (related to neurosensory changes associated with increased cerebral ammonia levels related to substance use disorder [alcohol], chronic viral hepatitis [B,C], hepatic encephalopathy, hepatic metabolic insufficiency, biliary cirrhosis, hereditary hemochromatosis, nonalcoholic fatty liver disease, autoimmune hepatitis) | Disoriented to person, place, time, and purpose; inability to follow directions or provide an adequate history; delusions; inappropriate behavior; violence that is directed to self or others; inappropriate affect; forgetfulness, anxiety, fearfulness, short attention span; personality changes; mood swings; difficulty or inability to perform mental tasks such as simple math; changed sleep patterns such as confusing day and night to extreme sleepiness; difficult slow or sluggish hand movement, jumbled slurred speech, or inability to perform familiar purposeful actions |
| 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 |
Before the Study: Planning and Implementation
Teaching the Patient What to Expect
- Discuss how this test can assist with determining the presence of liver or bone disease.
- Explain that a blood sample is needed for the test.
After the Study: Implementation & Evaluation Potential Nursing Actions
Avoiding Complications
- The patient with cirrhosis should be observed for development of ascites requiring strict attention to fluid and electrolyte balance.
- Interventions/actions related to skin include the following: Use tepid water, alkaline soap, and emollient lotions. Keep fingernails short and use mittens to discourage scratching. Assess for visible scratches, bruises, excoriation, rash, dermatitis/pruritus, dryness, scaliness, and jaundice. Monitor for elevated serum bilirubin levels, excess bile salt resulting in tissue irritation, and histamine release as well as jaundice associated with liver disease.
Treatment Considerations
General
- Monitor and trend vital signs and laboratory studies associated with hydration (BUN and Cr) and potassium loss due to nasogastric suction.
- Monitor and trend ALP; compare ALP with GGT, LFTs (Alb, ALT, AST, TBil, DBil, TP), or other related studies to track the course of disease and response to treatment.
- Note that PT will be prolonged and INR increased if liver function is significantly damaged.
Confusion
- Interventions/actions related to confusion include the following: Observe for altered attention span, inability to give an accurate history, loss of concentration, inability to follow commands, behavior that is inappropriate or violent, inappropriate affect. Administer prescribed medications, lactalose, and nonhepatic metabolized sedatives. Encourage family to assist in providing an emotionally stable environment. Institute fall precautions, assist with activity, lower bed position, use restraints as appropriate and necessary. Try reorientation to person, place, time, and purpose.
Fluid Volume
- Facilitate management of fluid volume excess.
- Interventions/actions related to fluid volume excess include the following: Assess for ascites in the peritoneal cavity as excess fluid may impinge on both respiratory and digestive function. Assess for signs of portal hypertension and gastrointestinal bleed. Measure abdominal girth at the same place each day, and assess for abdominal dullness (consistent with fluid accumulation) with percussion. Monitor fluid intake and urinary output, enforce ordered fluid limit, and administer prescribed diuretics (spironolactone). Facilitate paracentesis as needed. Use abdominal binder, and facilitate use of incentive spirometer. Collaborate with the HCP and pharmacist for fluid and electrolyte management if NPO status is required.
Safety Considerations
- Consider fall precaution interventions that can limit injury risk to those with progressive compromised bone stability or liver function, and confusion.
Nutritional Considerations
Nutrition
- Dietary recommendations will vary depending on disease condition and severity; e.g., a soft food diet is recommended if esophageal varices develop; fat substitutes are recommended if bile duct disease is diagnosed; limited salt intake is recommended if ascites develop; frequent small meals high in calories from carbohydrates or high fiber diet may be required as indicated.
- Consider barriers to eating such as impaired swallowing, psychological factors (anorexia, bulimia), lack of interest in food, inability to absorb nutrients, or inadequate financial resources.
- Symptoms of inadequate nutrition include weight loss regardless of sufficient intake, intake is less then the recommended dietary allowance, excessive hair loss, weakness, lack of interest in food or eating, pale mucous membranes, mouth sores, fatigue, listlessness.
- Interventions/actions related to nutrition include the following: Record daily weight, calorie count, and strict intake and output. Consider dietary consult. Assess current eating patterns and food attitudes. Provide a pleasant eating environment and culturally appropriate foods. Discourage caffeinated or carbonated drinks and alcohol that can interfere with adequate nutrition. Facilitate speech therapy or swallowing consult if needed. Monitor and trend laboratory values associated with nutrition, serum albumin, transferrin, RBC count, WBC count, and electrolytes. Administer ordered parenteral fluids, NSAIDs, opioids, antiemetics and nutrition supplements.
Clinical Judgement
- Consider how altered liver function can impinge on an individual’s ability to meet life goals by interfering with personal health and choose implementation strategies that will facilitate positive health choices.
Follow-Up Evaluation and Desired Outcomes
- Agrees to make lifestyle changes that will improve overall health.
- Understands that small, frequent meals throughout the day can increase overall caloric intake and improve nutritional status.
- Demonstrates awareness that cessation of weight loss with some weight gain may occur over a specified period of time.