CMP Panel: How to Read Blood Test Results

What Tests Are Included in the CMP?

 

The Comprehensive Metabolic Panel (CMP) is a broad screening tool includes 14 tests that evaluate your liver, kidneys, and more to provide a picture of your overall health. The panel looks at your organ function, electrolytes, blood sugar, and blood proteins. Along with the CBC and lipid panels, CMP is the most commonly ordered lab test panel when you go to see your doctor for an annual physical exam.

The CMP includes tests for:

• Liver function (ALP, ALT, AST, Bilirubin)

• Kidney function (BUN, Creatinine)

• Electrolytes and fluid balance (Sodium, Potassium, Carbon Dioxide, Chloride)

• Proteins (Albumin, Total Protein)

• Blood sugar (Glucose)

• Calcium

 

What Are the Consequences of High or Low CMP Lab Test Values?

 

We will now explain the potential causes for high or low blood levels of these variables so that  you can discuss them with your physician.

 

Alanine aminotransferase (ALT, SGPT)

Included in the CMP panel

ALT normal values are:

• 10-55 U/liter for males
• 10-55 U/liter for females

Alanine aminotransferase is an enzyme made by your liver. ALT is important to test to determine whether your liver is performing at its best.

High ALT or SGPT

• The liver cells might be seriously damaged, to the point of necrosis
• It might be a sign of extensive trauma to the liver, left heart failure, cirrhosis, or jaundice
• Might also be a sign of muscular dystrophy, fatty liver, myocardial infarction, and liver tumors

Low AST or SGPT

• Low values of ALT indicate pyridoxal phosphate deficiency that can result in various health complications including epilepsy

 

Albumin

Included in the CMP panel

Normal albumin values

3.1-4.3 g/dl for men and women

Albumin is a protein synthesized by the liver and can be an indicator of the liver’s synthetic ability. However, because it has a long half-life of 20-30 days, and levels often remain normal even in acute disease, it is not always useful in assessing acute hepatic injury. Albumin is one of the most important proteins in the human body. It helps to carry nutrients to various tissues and it prevents blood vessels from leaking fluids.

When albumin is very low:

• This is a sign of acute or chronic inflammation
• Decreased albumin levels can occur in chronic diseases such as cirrhosis, cancer and malnutrition.
• Albumin levels might drop if the liver has problems synthesizing this protein properly, so it might indicate liver damage
• The transportation of bile acids and metal ions might be affected if the albumin levels get too low

 

Alkaline phosphatase ALP (Adults)

Included in the CMP panel

Alkaline phosphatase is also known as ALP and it is found in different tissues in the body. This enzyme is mostly present in the bones and liver. It plays a vital role in bone formation and mineralization.

ALP Normal values

• 45-115 U/liter for males
• 30-100 U/liter for females

High ALP

• It might be a sign of biliary obstruction or liver diseases such as hepatitis or cirrhosis
• Sign of bone disorder or even renal problems
• In some cases, it might indicate thyroid issues

Low ALP

• It might signify nutritional deficiencies such as a lack of vitamin B12, magnesium or zinc
• Might be caused by severe anemia

 

Aspartate aminotransferase (AST, SGOT)

Included in the CMP panel

AST or SGOT normal levels

• 10-40 U/liter for men
• 9-25 U/liter for women

Aspartate aminotransferase is an enzyme found in most tissues in the human body, particularly in the liver and the heart. It has multiple functions in the human body and abnormal levels usually indicate a liver problem.

High AST or SGOT

• This could be a sign of liver cell necrosis or obstructive jaundice
• It might also signify hepatitis or a liver problem caused by drugs and medications
• Since this enzyme is found in the muscles, it might be a sign of skeletal muscle, inflammatory disease or even heart failure. Excessive exercise can raise it.

Normally, the levels of aspartate aminotransferase should be low. Problems appear when these levels get very high due to organ failure or inflammation.

 

Bilirubin, direct

Included in the CMP panel

Bilirubin normal values

• 0-0.4 mg/dl for men and women

Bilirubin is a yellow substance involved in the process of cleaning organic waste from the body such as dead red blood cells, etc. It is excreted in the bile and urine and it consists of direct and total bilirubin. When doing a blood test, your results might indicate the levels of direct and total bilirubin as both of these are important to diagnose certain diseases.

High direct albumin

• It might signify a biliary tree obstruction, cholestasis, and damage to the hepatic cells
• The patient might have the Dubin-Johnson syndrome which is characterized by an increase of direct bilirubin in the liver

Low direct bilirubin

• Low levels of direct bilirubin are usually not a cause of concern. These levels might be temporarily lowered by caffeine consumption or barbiturates

 

Bilirubin, total

Total bilirubin normal values

• 0-1.0 mg/dl for men and women

This is the total amount of bilirubin enzymes in your body, including direct and indirect ones. Low levels of total bilirubin are not a problem in most cases. You should see a doctor when these levels are elevated as they can signify different types of damages to your organs.

High total bilirubin

• It might be a sign of neonatal physiological jaundice
• High levels might be caused by damage to the hepatic cells caused by toxins or inflammation
• It might be a sign of biliary tree obstruction

 

Calcium

Included in the CMP panel

Calcium normal values

• 5-10.5 mg/dl for men and women

Calcium is one of the most important minerals in the body. Calcium is directly involved in the mineralization and growth of bones and it ensures that teeth remain in good condition.

High calcium

• This might be a sign of hyperparathyroidism, bone disorders, malignant disease such as metastatic carcinoma of breast and kidney, etc.
• Your blood might contain too much vitamin D which leads to intoxication
• Acromegaly or dehydration

Low calcium

• It might be a sign of hypoparathyroidism or chronic kidney failure
• Might be caused by a deficiency of vitamin D or magnesium
• The patient might have acute pancreatitis, anemia or problems with the pituitary gland

 

Carbon dioxide, total

Included in the CMP panel

Carbon dioxide normal values

• 24-30 mmol/liter for men and women

Carbon dioxide is a byproduct of the food metabolization process. This gas is released into the bloodstream when cells are broken down in simpler substances. The blood full of carbon dioxide returns to the lungs where this gas is eliminated through respiration.

High carbon dioxide

• It might be a sign of respiratory acidosis resulted from a poor gas exchange in the body
• Can also be caused by metabolic acidosis, especially if it is accompanied by multiple episodes of vomiting

Low carbon dioxide

• It might signify tubular acidosis of the kidneys
• Might be a sign of loss of alkaline fluids through the intestines or compensated respiratory alkalosis

 

Chloride

Included in the CMP panel

Chloride normal values

• 100-108 mmol/liter for men and women

Chloride forms when the element chlorine gains an electron. This is an important electrolyte that helps to maintain cell homeostasis or balance.

High Chloride

• It might be caused by metabolic acidosis, especially when it is accompanied by loss of fluids caused by diarrhea
• It can also be caused by severe dehydration or a problem with the kidneys such as renal tubular acidosis or acute renal failure
• Hyperparathyroidism can also cause chloride levels to increase

Low Chloride

• It might be caused by too much vomiting or prolonged episodes of diarrhea
• Low levels can also be caused by gastric problems such as gastric suction or gastric secretion
• Excessive sweating or respiratory acidosis can also make the chloride levels drop significantly
• Adrenal insufficiency may lower chloride blood levels
• Low blood chloride levels can be caused by drugs such as:
• These medication types can result in low chloride:
• Laxatives
• Diuretics
• Corticosteroids (long-term treatments)
• Bicarbonates

 

Creatinine

Included in the CMP panel

Creatinine normal levels

• 6-1.5 mg/dl for men and women

Serum creatinine (a blood measurement) is an important indicator of kidney health because it is an easily measured byproduct of muscle metabolism that is excreted unchanged by the kidneys. It is eliminated from the body by kidneys through urine. The creatinine test is used to measure creatinine clearance as a way to assess kidney function. Creatinine is one of the variables used to estimate eGFR - Estimated glomerular filtration rate- which is one of the best test to measure your level of kidney function and determine your stage of kidney disease. Your doctor can calculate it from the results of your blood creatinine test, your age, body size and gender. Your GFR tells your doctor your stage of kidney disease and helps the doctor to plan your treatment. If your GFR number is low, your kidneys are not working as well as they should. The earlier kidney disease is detected, the better the chance of slowing or stopping its progression. People with high creatinine (low eGFR) should get a Cystatin C test which may be more accurate in certain cases. Elevated creatinine is not always representative of a true reduction in eGFR. A high reading may be due to increased production of creatinine not due to decreased kidney function, to interference with the assay, or to decreased tubular secretion of creatinine. An increase in serum creatinine can be due to increased ingestion of cooked meat (which contains creatinine converted from creatine by the heat from cooking) or excessive intake of protein and creatine supplements, taken to enhance athletic performance. Intense exercise can increase creatinine by increasing muscle breakdown. Dehydration secondary to an inflammatory process with fever may cause a false increase in creatinine concentrations not related to an actual kidney injury. Several medications can interfere with the assay. Creatinine secretion by the tubules can be blocked by some medications, again increasing measured creatinine.

High creatinine

• Too much creatinine in the body might be a sign of renal failure or kidney dysfunction
• Hyperthyroidism can also be a cause of too much creatinine building up in the body as well as acromegaly
• Eating too many meals containing meat can increase the level of creatine and creatinine in the body
• Taking creatine supplements can falsely increase creatinine blood levels.
• Certain medications can increase creatinine blood levels, so talk to your doctor.

Low creatinine

• This might be a sign of excessive muscle loss, probably caused by muscular dystrophy
• It can also be a sign of liver problems or a lack of protein in your diet

 

Glucose, fasting

Glucose normal values

• 70-110 mg/dl for men and women

Glucose is basically the amount of sugar you have in your blood. The entire human body uses glucose as a fuel source, but too much of it can be a real problem.

High glucose

• This might be a sign of diabetes, increased insulin resistance, increased epinephrine, pancreatic disorders or endocrine problems
• Very high values are commonly associated with acute myocardial infarction, kidney disease or chronic liver disease

Low glucose

• Although rare, low glucose values might be caused by a tumor that makes the pancreas produce too much insulin
• It might also be a sign of serious liver disease or renal disorders

 

Potassium

Potassium normal values

• 5-5.2 mmol/L

Potassium ions are vital for the functioning of all living cells. The transfer of potassium ions across nerve cell membranes is necessary for normal nerve transmission; potassium deficiency and excess can each result in numerous signs and symptoms, including an abnormal heart rhythm and various electrocardiographic abnormalities. Fresh fruits and vegetables are good dietary sources of potassium. The body responds to the influx of dietary potassium, which raises serum potassium levels, with a shift of potassium from outside to inside cells and an increase in potassium excretion by the kidneys.

Low Potassium

• Hypokalemia (low potassium blood level) always occurs as a result of excessive loss of potassium through the urine, sweat or stool. It is always a symptom of another disorder, rather than a disease that occurs by itself.
• The excessive excretion of potassium in the urine may result from the use of diuretic drugs (which increases urination), a deficiency of magnesium in the blood, excessive mineralocorticoids such as aldosterone in the blood which affect the electrolyte and fluid balance in the body (usually caused by endocrine diseases), kidney disorders, or from the use of high doses of penicillin.
• Gastrointestinal losses of potassium usually are due to prolonged diarrhea or vomiting, chronic laxative abuse, inadequate dietary intake of potassium, intestinal obstruction or infections such as fistulas in the intestines which continually drain intestinal fluids.
• Additionally, excessive perspiration due to hot weather or exercise can cause hypokalemia.
• Some drugs can keep your kidneys from removing enough potassium. This can cause your potassium levels to rise.

High Potassium

The symptoms of an elevated potassium level are generally few and nonspecific. Nonspecific symptoms may include feeling tired, numbness and weakness. Occasionally palpitations and shortness of breath may occur. Hyperventilation may indicate a compensatory response to metabolic acidosis, which is one of the possible causes of hyperkalemia (high potassium).  

• Often, however, the problem is detected during screening blood tests for a medical disorder, or after hospitalization for complications such as cardiac arrhythmia or sudden cardiac death. High levels of potassium (> 5.5 mmol/L) have been associated with cardiovascular events.
• Decreased kidney function is a major cause of hyperkalemia.

 

Sodium

Sodium normal values

• 135-145 mmol/liter for men and women

Sodium is another important electrolyte in the body. It helps to keep the cell fluid balance at normal levels and it performs other important body functions.

High sodium

• This can be a sign of Cushing's syndrome or water loss through the skin
• Too much sodium might also be a sign of increased renal sodium conservation in hyperaldosteronism

Low sodium

• Also known as hyponatremia, too little sodium in the blood might signify diuretics abuse, salt-losing nephropathy (kidney disease) or excessive sweating
• Low sodium might also be caused by excessive vomiting or diarrhea
• A low sodium level has many causes, including consumption of too many fluids, kidney failure, heart failure, cirrhosis, and use of diuretics.
• Symptoms result from brain dysfunction.
• At first, people become sluggish and confused, and if hyponatremia worsens, they may have muscle twitches and seizures and become progressively unresponsive.
• Restricting fluids and stopping use of diuretics can help, but severe hyponatremia is an emergency requiring use of drugs, intravenous fluids, or both.