All You Need to Know About a VMA Test

Submitted on March 27, 2012

Definition

VMA lab test stands for 'Vanillylmandelic acid' and is an end-stage metabolite (intermediates or products of metabolism), adrenalin, and norepinephrine (hormones and neurotransmitter). VMA is generally found in human urine, along with other hormones released by the adrenalin glands in the body to fight stress. It is observed that in patients with tumors that secrete catecholamines the levels of urinary VMA are higher than normal.

The VMA test is basically used to detect neuroblastomas in children that have abdominal mass or other symptoms that are associated with the disease. The VMA test is carried out in conjunction with the homovanillic acid test to diagnose neuroblastomas, to monitor the effectiveness of the treatment and also to check for the recurrence of neuroblastomas. A urine creatinine is almost always done, especially with random urine testing, and tests results are usually reported as ratios of VMA-to-creatinine and HVA-to-creatinine. The reason being that creatinine is a substance that is excreted in the urine at a relatively constant rate; and this serves as a comparison to the rate of VMA and HVA excretion.

Urine VMA Test

Medically termed as an Vanillylmandelic acid test, the urine VMA test is primarily a medical test that is ordered by a doctor when suspecting a child of suffering from symptoms including the development of a hard lump in the abdominal area as well as a lack of appetite. The development of this tumor around the belly is usually one of the foremost indicators of the condition and will also cause a significant amount of pain that will restrict the child's ability to eat and swallow any foods. In some cases, the tumor is also likely to press onto the spine - thereby causing a significant amount of pain when it comes to walking. There are a number of further complications that are likely to develop if the tumor is allowed to grow any further. The tumor is likely to cause a significant amount of pain when pushing onto the bones while, in the event that it affects the bone marrow - it will significantly affect the production of red blood cells. Some other physiological symptoms that one is more likely to notice include significant tiredness, bruising around the eyes, purple spots on the skin as well as drooping eyelids.

The urine VMA test is performed on an individual's urine in an effort to detect the presence of Vanillylmandelic acid that is an end stage metabolite and is produced within the body along with a host of other hormones. These hormones are all released by the adrenal glands in an effort to help the body fight stress. Studies have shown that although the causing factor - the neuroblastomas are considered to be rare cancers, they are known to be the most common cancers affecting children. Recent figures show that as many as about 650 new cases of the condition are reported each year in the United States of America alone. Most cases show that children between the ages of 2 and 5 account for as many as about 90% of all cases, while there are a few cases in which the baby may be born with the condition. One factor that place certain individuals at more of a risk than others include a family history of the condition. Anxiety and stress are also known to be common contributing factors and should be guarded against as much as possible.

Reasons For Conducting This Test

VMA lab tests are done when the following signs and symptoms show up in a patient. The presence of any unusual and hard lump in the abdomen, especially near the belly is a symptom. Also the lack of appetite or abdominal pain is a sign to check for neuroblastomas. At times any tumors in the neck which cause swelling and make it hard to swallow or breathe are tell tale signs.

Also tumors that press on nerves by the spine may affect a child's ability to walk. If the tumor spreads to the bones, it may cause pain in the bones, and also may affect the production of blood cells if it spreads to the bone marrow. Fatigue, pallor, and bleeding are also a direct result of tumors in the bone marrow. Bruising around the eyes, drooping eyelids, purple spots on the skin, bladder and bowel dysfunction along with muscle spasms are also noticed in neuroblastoma patients.

Preparation and Results

As part of the VMA test preparation, you need to speak to your doctor about different aspects that can affect the VMA test results. When preparing for the VMA test, diet is another aspect that needs to be kept in minds. You should avoid caffeine in your diet. Drug abuse and stress can also affect your results. As a result, it is important to consult your physician before you choose to have a test performed and find out also if any medications that you may be taking are likely to affect the test in any way. The VMA test kit contain VMA test instructions that will require the collection of urine samples over a period of about 24 hours. These samples need to be refrigerated during this period after which a single urine sample will be selected randomly for the VMA urine test to be performed on it.

When undergoing a VMA blood test, it is important to understand that the amount of VMA found in the urine sample in no way corresponds to the size of the tumor present in the body. Some doctors will tend to evaluate the VMA to HVA ratio with the neuroblastoma test that is sometimes performed alongside the VMA test. The VMA test results used in this relation conform to the scale of the lower numbers representing a poor prognosis. Because of the fact that the testing requires a certain amount of specialist equipment as well as a full laboratory, it is unlikely that you will be able to perform the test at your doctor's clinic.

There are a lot of false positive results with the test, the reason being that VMA lab tests are sensitive to many other outside influences.; If a person has more than normal amount of VMA in his urine, further investigation is necessary to determine its cause. Amount of VMA produces does not have any direct relation to the size of the tumor, as this is mostly a physical characteristic of tumor tissue. Finally a doctor must always be consulted while testing for VMA, or before discontinuing any medication.

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