What does a cortisol test tell you?

A cortisol level test uses a blood sample to measure the level of cortisol in your blood.

Cortisol is a steroid hormone released by the adrenal glands. The adrenal glands sit on top of your kidneys. A cortisol level test may also be called a serum cortisol test.

What is cortisol?

Cortisol is a steroid hormone produced by the adrenal glands. Whenever you experience something your body perceives as a threat, like a large dog barking at you, a chemical known as adrenocorticotropic hormone (ACTH) is released in your brain. This triggers your adrenal glands to release cortisol and adrenaline.

Cortisol is the main hormone involved in stress and the fight, flight, or freeze response. This is a natural and protective response to a perceived threat or danger. Increased levels of cortisol result in a burst of new energy and strength.

In the fight, flight, or freeze response, cortisol suppresses any functions that are unnecessary or detrimental to that response. During a fight, flight, or freeze response, you can have:

• a rapid heart rate

• dry mouth

• stomach upset

• diarrhea

• panic

Cortisol release also:

• suppresses your growth processes

• suppresses your digestive system

• suppresses your reproductive system

• changes how your immune system responds

Why is the cortisol level test performed?

The cortisol level test checks whether your cortisol production levels are too high or too low. Certain conditions, such as Addison’s disease and Cushing’s disease, affect the amount of cortisol your adrenal glands produce.

The test is used in the diagnosis of these diseases and as a way to assess the functioning of the adrenal and pituitary glands.

Cortisol plays a role in several systems in the body, including:

• stress responses

• immune system

• nervous system

• circulatory system

• skeletal system

• the breakdown of proteins, fats, and carbohydrates.

How to prepare for the cortisol level test

Cortisol levels vary throughout the day but are usually highest in the morning. Your doctor will usually request that the test be done in the morning. You don’t need to fast for a cortisol test.

Certain drugs affect cortisol levels. Your doctor may request that you not take these drugs before the test is done. Cortisol levels are sometimes increased by:

• drugs containing estrogen

• synthetic glucocorticoids, such as prednisone

• pregnancy

Cortisol levels are sometimes decreased by:

• drugs containing androgens

• phenytoin

Cortisol levels can also be affected by physical and emotional stress and illness. This is due to the increased release of ACTH by the pituitary gland during the usual stress response.

What do the results of the cortisol level test mean?

Standard results for a blood sample taken at 8 a.m. range between 6 and 23 micrograms per deciliter (mcg/dL). Many laboratories have different measuring techniques, and what’s considered standard may vary.

Higher-than-usual cortisol levels may indicate that:

• your pituitary gland is releasing too much ACTH due to a tumor or excess growth of the pituitary gland

• you have a tumor in your adrenal gland, resulting in excess cortisol production

• you have a tumor elsewhere in your body that’s involved in cortisol production

Lower-than-usual cortisol levels may indicate that:

• you have Addison’s disease, which occurs when the production of cortisol by your adrenal glands is too low

• you have hypopituitarism, which occurs when the production of cortisol by your adrenal glands is too low because the pituitary gland is not sending proper signals

What is an LH test for?

This test measures the level of luteinizing hormone (LH) in your blood.

LH is made by your pituitary gland. In women, the pituitary sends out LH during the ovulation part of the menstrual cycle. This tells the ovaries to release a mature egg. In men, LH causes the testes to make testosterone.

This test can help find out the cause of fertility problems in both men and women. A higher LH level can help a woman find out the point in her cycle when it's best to try to conceive.

This test can also help diagnose a pituitary gland disorder.

Why do I need this test?

You may need this test if you are having trouble getting pregnant (infertility) and your healthcare provider needs to find out the cause. You may also have this test if you have symptoms of a pituitary disorder, such as a benign tumor in the pituitary gland (called a prolactinoma). Symptoms include:

• Males have trouble getting or keeping an erection (impotence) or have a lower sex drive

• Females who aren't pregnant or nursing start to produce breastmilk (lactation)

You may also have this test if you are having irregular menstrual periods.

What other tests might I have along with this test?

You may also need other tests for infertility. If you're a male, you may need a semen analysis, genetic tests, and other blood tests to measure different hormones. If you're a female, you may order other hormone-level blood tests, genetic tests, and basal body temperature testing. You may also need a pelvic ultrasound and a hysteroscopy to look at the inside of your uterus.

What do my test results mean?

Test results may vary depending on your age, gender, health history, and other things. Your test results may be different depending on the lab used. They may not mean you have a problem. Ask your healthcare provider what your test results mean for you.

Results are given in international units per milliliter (IU/mL). The normal range for a woman varies, depending on the timing of her menstrual cycle. Here are normal ranges:

• Men: 1.24 to 7.8 IU/mL

• Women, follicular phase of menstrual cycle: 1.68 to 15 IU/mL

• Women, midcycle peak: 21.9 to 56.6 IU/mL

• Women, luteal phase: 0.61 to 16.3 IU/mL

• Women, postmenopausal: 14.2 to 52.3 IU/mL

If you aree female, abnormally high levels of LH during nonovulatory times in your menstrual cycle may mean you are in menopause. It may also mean that you have a pituitary disorder or polycystic ovary syndrome. Low levels of LH may mean you have a pituitary disorder, anorexia, malnutrition, or are under stress.

If you are male, abnormally high LH levels along with low levels of testosterone may mean that your testicles aren't responding to LH's signal to make more testosterone. Low levels of LH may mean that your pituitary gland isn't making enough LH. That can lead to too little testosterone production

What might affect my test results?

If you are female, your results will vary depending on what day in your menstrual cycle the test is done.

How do I get ready for this test?

You don't need to get ready for this test. Be sure your healthcare provider knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illegal drugs you may use.  

what is FSH blood test?

Follicle-stimulating hormone (FSH) is a hormone associated with reproduction and the development of eggs in women and sperm in men. This test measures FSH in the blood.

FSH is made by the pituitary gland, a small organ located in the center of the head behind the sinus cavity at the base of the brain. Control of FSH production is a complex system involving the hypothalamus in the brain, the pituitary gland, and the hormones produced by the ovaries or testicles.

The hypothalamus releases gonadotropin-releasing hormone (GnRH), which stimulates the pituitary to release FSH and luteinizing hormone (LH), a closely-related hormone involved in reproduction.

Disorders affecting the hypothalamus, pituitary, and/or the ovaries or testicles can cause the production of too much or too little FSH, resulting in various conditions such as infertility, abnormal menstrual cycles, or early (precocious) or delayed puberty.

Purpose of the test

The FSH test is used to evaluate fertility issues, the health of your reproductive organs (ovaries or testicles), or pituitary function. In children, it is utilized to evaluate early or delayed puberty.

What does the test measure?

The test for FSH may be used with other hormone tests such as LH, testosterone, estradiol, and/or progesterone to help:

• Determine the cause of infertility

• Diagnose conditions associated with dysfunction of the ovaries or testicles

• Aid in the diagnosis of pituitary or hypothalamus disorders, which can affect FSH production

In women, FSH levels are also useful in:

• The investigation of menstrual irregularities

• Predicting when or if a woman is entering menopause

FSH levels help determine the reason for a low sperm count in men.

In children, FSH and LH help diagnose delayed or precocious (early) puberty. Irregular timing of puberty may be an indication of a more serious problem involving the hypothalamus, the pituitary gland, the ovaries or testicles, or other systems.

The measurement of LH and FSH may differentiate between normal patterns of development and true disease. Once it is established that symptoms are a result of true disease, further testing can identify the underlying cause.

When should I get this test?

For a woman, an FSH test may be ordered when she is having difficulty getting pregnant, has irregular or absent menstrual periods, or sometimes when it is suspected that she has entered menopause.

The test may be ordered when a man’s partner cannot get pregnant, when the man has a low sperm count, or when he has low muscle mass or decreased sex drive, for example.

In both women and men, testing may be ordered when a health care practitioner suspects a pituitary disorder is present. This can affect the production of several different hormones, so there may be signs and symptoms in addition to some of those listed above. They can include fatigue, weakness, unexplained weight loss, and decreased appetite, to name a few.

In children, FSH and LH may be ordered when a boy or girl does not appear to be entering puberty at an appropriate age (either too late or too soon). Signs of puberty may include:

• Breast enlargement in girls

• Growth of pubic hair

• Growth of the testicles and penis in boys

• Beginning of menstruation in girls

What is a Ferritin blood test?

A ferritin blood test measures the level of ferritin in your blood. Ferritin is a protein that stores iron inside your cells. You need iron to make healthy red blood cells. Red blood cells carry oxygen from your lungs to the rest of your body. Iron is also important for healthy muscles, bone marrow, and organs, including brain development in children.

Too little or too much iron in your body can cause serious health problems if not treated. A ferritin blood test can show how much iron you have stored in your body.

Other names: serum ferritin, serum ferritin level, ferritin serum

What is it used for?

A ferritin blood test is used to help check your iron levels. It can help your health care provider find out if your body is storing the right amount of iron to stay healthy.

The test may also be used to:

• Help diagnose or rule out conditions related to iron levels, including:

• Hemochromatosis, having too much iron in your body (also called iron overload)

• Iron deficiency anemia, having too few red blood cells because you lack iron

• Liver diseases (much of the ferritin in your body is stored in your liver.)

• Restless legs syndrome, a tingling or burning feelings in your legs that may be caused by a lack of iron

• Adult Still disease (also called adult-onset Still disease or AOSD), an uncommon disease that causes joint pain, fever, and rash, often with high ferritin levels

• Monitor chronic (long-lasting) conditions that may affect your irons levels, such as cancer, kidney disease, and autoimmune diseases

If you're being treated for problems with iron, the test may be used to check how well the treatment is working.

Why do I need a ferritin blood test?

You may need this test if you have symptoms of iron levels that are too low or too high.

Symptoms of iron levels that are too low include:

• Shortness of breath

• Weakness or fatigue

• Dizziness

• Arrhythmia (a problem with the rate or rhythm of your heartbeat)

Symptoms of iron levels that are too high can vary and tend to get worse over time. Symptoms may include:

• Weakness or fatigue

• Joint pain, commonly in the knees or hands

• Loss of interest in sex or erectile dysfunction (ED)

• Abdominal (belly) pain

• Change in skin color, which may look gray, metallic, or bronze

You may also need this test if the results of other blood tests show that you have low hematocrit or hemoglobin levels.

What do the results mean?

Lower than normal ferritin levels may mean you have iron deficiency anemia, or another condition related to low iron levels. Iron deficiency anemia is a common type of anemia, in which your body doesn't make enough red blood cells. Without treatment it can lead to heart problems, infections, slow growth and brain development in children, and other health issues.

Higher than normal ferritin levels can mean you have too much iron in your body. Conditions that cause increased iron levels include:

• Liver disease

• Alcohol use disorder

• Hemochromatosis

• Hyperthyroidism

If your ferritin results are not normal, it does not always mean you have a medical condition that needs treatment. Certain medicines can decrease or increase your ferritin levels. If you have questions about your results, talk with your health care provider.

What does vitamin B-12 test for?

Purpose of the test

The purpose of vitamin B12 testing is to determine whether you have a deficiency or a lower-than-normal level of B12 in your body. Sometimes a vitamin B12 level will be tested by itself, and other times it will be measured along with other tests to diagnose or monitor certain health problems.

Your doctor might order a vitamin B12 test if you show symptoms of anemia or issues with the nervous system like mental changes, weakness, loss of balance or numbness, pain, and tingling in the arms and legs. A vitamin B12 test can also be ordered as a follow-up if you had an abnormal blood test that suggests megaloblastic anemia, when red blood cells are unusually large and do not function properly.

What does the test measure?

The test measures your vitamin B12 levels, which are important for many aspects of health. Adequate levels of vitamin B12 are needed for your body to maintain a healthy nervous system, make red blood cells, and create DNA, the genetic material in all of our cells.

When should I get this test?

Up to 15% of people in the U.S. have a vitamin B12 deficiency. Testing is usually performed when you have symptoms of a vitamin B12 deficiency, such as anemia or nervous system problems. Some people are at a greater risk of vitamin B12 deficiency due to age or preexisting health conditions. They may undergo regular vitamin B12 testing to check whether their levels are normal.

Anemia is one factor related to inadequate vitamin B12, with symptoms including fatigue, difficulty concentrating, pale skin, shortness of breath, diarrhea, nausea, and loss of appetite. With anemia, your body doesn’t have enough healthy red blood cells to carry oxygen to tissues.

A vitamin B12 deficiency can lead to a type of anemia known as megaloblastic anemia. Megaloblasts may be detected through routine blood testing before you develop symptoms of anemia. When this happens, follow-up testing is typically performed, including a vitamin B12 test.

Nervous system symptoms are another trigger for vitamin B12 testing. Common symptoms include neuropathy, weakness, poor balance, confusion, and dementia.

And you might have risk factors associated with a vitamin B12 deficiency, including age (75 years or older), lack of protein in the diet, medications that interfere with vitamin B12 absorption like histamine blockers, or decreased absorption of vitamin B12 because of a stomach disease like celiac, cancer, or pancreatic insufficiency.

People more likely to experience low vitamin B12 levels include older adults, children, vegans and vegetarians, diabetics, those who have had gastric bypass surgery, women who are breastfeeding, and if you have a condition that can impact absorption like Crohn’s disease.

Your doctor can best assess the nuances involved in determining whether you should get vitamin B12 testing because many of these symptoms overlap with other health conditions and could require different types of screening.

what does total IgE test for?

What is Total IgE?

Total IgE measures the level of antibodies in the blood made by the immune system in response to an allergen.

Immunoglobulin E (IgE) is an antibody that causes an allergic reaction. When exposed to an allergen (typically a harmless substance that the immune system considers dangerous, such as peanuts), the body produces specific IgE antibodies designed to recognize that allergen in the future. Then, with repeated exposure to the same allergen, the immune system quickly produces large numbers of allergen-specific IgE particles to identify and eliminate the allergen.

What is Total IgE?

The total IgE test detects the presence of IgE antibodies in the blood, indicating an increased chance of an allergic reaction. The test for allergen-specific IgE particles is then used to obtain information about the specific substance causing the allergic reaction.

How do I know if I have allergies?

Allergic reactions range from localized red spots, itchy skin, to anaphylaxis, which includes a sudden drop in blood pressure and difficulty breathing.

Allergic reactions can vary greatly in type and severity depending on the individual and allergy. The following symptoms are strong indications that IgE needs to be measured:

• Itchy eyes or watery eyes

• Sneezing and/or coughing

• Intermittent or persistent itching, hives

• Stuffy nose

• Persistent diarrhea

• Difficulty breathing

• Nausea or vomiting 44

What is a normal IgE level?

IgE test results are expressed in Fluorescent Assay Standard Units (FSU). A number less than 0.01 FSU indicates no detectable IgE.

Generally, the higher the IgE level, the higher the risk of allergic symptoms. Each potential allergen is assigned a class according to this level as shown below.

Class 0/1

0.01–0.34 BSS

Clinical significance not established

Class 1

0.35-0.70

Low sensitivity

Class 2

0.71-3.50

Moderate sensitivity

Class 3

3.51-17.50

High Sensitivity

Class 4 or higher

17.51-50.00

Ultra High Sensitivity

Class 5

50.01-100.00

Ultra High Sensitivity

>100

Highly sensitive

What does high IgE mean?

Higher IgE levels are more likely to cause symptoms of allergy to a specific allergen, but lower classes of allergens also need to be controlled. They can contribute to the buildup of allergy burden during allergy season, for example.

What if IgE is elevated?

If your IgE levels are elevated due to indoor, outdoor or food allergies, a board-certified allergist can work with you to develop a program to help relieve your symptoms.

This may include the use of antihistamines and other drugs, allergen avoidance, and immunotherapy.

What is RA test?

What is a rheumatoid factor (RF) test?

The rheumatoid factor (RF) test looks for rheumatoid factor (RF) in a blood sample. Rheumatoid factor is a protein produced by the immune system.

Your immune system makes proteins called antibodies to attack germs that can normally make you sick. However, rheumatoid factor is an antibody that sometimes mistakenly attacks the body's healthy cells and tissues.

When this happens, you have an autoimmune disease.

Not everyone has rheumatoid factor in their blood. And some people who have them are healthy. However, if you have certain symptoms and higher levels or rheumatoid factor, you may have an autoimmune disease or other health problem associated with high RF levels.

The

RF test is primarily used in conjunction with other tests to diagnose rheumatoid arthritis.

Rheumatoid arthritis (RA) is a type of autoimmune disease that damages joints and causes pain, swelling, and stiffness. It is a chronic (long-term) condition that can affect organs and cause other symptoms.

High levels of rheumatoid factor can also be a sign of other autoimmune diseases, some infections, and some types of cancer.

Other Name: RF Blood Test

What is it used for?

The RF test is often used to diagnose rheumatoid arthritis and other autoimmune diseases.

RF testing can also be used to understand how severe your rheumatoid arthritis is and whether it can affect your organs. RF testing by itself cannot diagnose a health problem.

Why is RF testing needed?

If you have rheumatoid arthritis symptoms, you may need an RF test. Symptoms often start in the wrists, hands, and feet.

They usually affect the same joints on both sides of the body and tend to come and go.

Symptoms of rheumatoid arthritis may include:

• Joint pain

• Tenderness, swelling, and warmth of the joint

• Joint stiffness that lasts longer than 30 minutes

• Fatigue

• Occasional low fevers

• Loss of appetite

• Problems outside of the joints that may include dry eyes or mouth, firm lumps under the skin, or anemia

What do the results mean?

An RF test alone cannot diagnose any conditions. To make a diagnosis, your provider will look at the results of other tests along with your symptoms and medical history.

A negative (normal) result means that you have little or no rheumatoid factor in your blood.

However, that does not rule out rheumatoid arthritis or other health problems. Many people with rheumatoid arthritis have little or no rheumatoid factor. If you have rheumatoid arthritis symptoms but your RF test results are normal, your doctor may order additional tests to make a diagnosis.

A positive (abnormal) result means a higher level of rheumatoid factor was detected in the blood. This does not always mean that the symptoms are caused by rheumatoid factor.

However, the higher the RF test result, the higher the chance that a person has a rheumatoid factor-related disorder. Your doctor may do more tests to find out if you have a disease, such as:

• Rheumatoid arthritis or other autoimmune diseases

• Chronic infections

• Certain types of cancer

Anything else I should know about the RF test?

Radiofrequency testing is not used to diagnose osteoarthritis. Although rheumatoid arthritis and osteoarthritis both affect joints, they are very different conditions. Osteoarthritis is not an autoimmune disease and is not related to rheumatoid factor.

Researchers aren't sure what causes osteoarthritis. It mainly affects the elderly.