Tests, General Diagnostic

Addison's Disease

Measuring your blood levels of sodium, potassium, cortisol and ACTH gives your doctor an initial indication of whether adrenal insufficiency may be causing your signs and symptoms. A blood test also can measure antibodies associated with autoimmune Addison’s disease.

Myasthenia Gravis

A special blood test can detect the presence of immune molecules or acetylcholine receptor antibodies. Most patients with myasthenia gravis have abnormally elevated levels of these antibodies. However, antibodies may not be detected in patients with only ocular forms of the disease.

Another test is called the edrophonium test. This approach requires the intravenous administration of edrophonium chloride or Tensilon(r), a drug that blocks the degradation (breakdown) of acetylcholine and temporarily increases the levels of acetylcholine at the neuromuscular junction. In people with myasthenia gravis involving the eye muscles, edrophonium chloride will briefly relieve weakness. Other methods to confirm the diagnosis include a version of nerve conduction study which tests for specific muscle “fatigue” by repetitive nerve stimulation. This test records weakening muscle responses when the nerves are repetitively stimulated. Repetitive stimulation of a nerve during a nerve conduction study may demonstrate decrements of the muscle action potential due to impaired nerve-to-muscle transmission.

A different test called single fiber electromyography (EMG), in which single muscle fibers are stimulated by electrical impulses, can also detect impaired nerve-to-muscle transmission. EMG measures the electrical potential of muscle cells. Muscle fibers in myasthenia gravis, as well as other neuromuscular disorders, do not respond as well to repeated electrical stimulation compared to muscles from normal individuals. Computed tomography (CT) may be used to identify an abnormal thymus gland or the presence of a thymoma.

A special examination called pulmonary function testing – which measures breathing strength – helps to predict whether respiration may fail and lead to a myasthenic crisis.

Lupus, SLE (Systemic Lupus Erythromatosis) / Risk

Diagnosing lupus can be a difficult and slow process. It may take months or even years for doctors to piece together the symptoms to diagnose this complex disease accurately.

No single test can determine whether a person has lupus, but several laboratory tests may help the doctor to make a diagnosis. The most useful tests identify certain autoantibodies often present in the blood of people with lupus. For example, the antinuclear antibody (ANA) test is commonly used to look for autoantibodies that react against components of the nucleus, or “command center,” of the patient’s own cells.

Most people with lupus test positive for ANA; however, there are a number of other causes of a positive ANA besides lupus, including infections, other rheumatic or immune diseases, and occasionally as a finding in normal healthy adults. The ANA test simply provides another clue for the doctor to consider in making a diagnosis.

In addition, there are blood tests for individual types of autoantibodies that are more specific to people with lupus, although not all people with lupus test positive for these and not all people with these antibodies have lupus. These antibodies include anti-DNA, anti-Sm, anti-RNP, anti-Ro (SSA), and anti-La (SSB). The doctor may use these antibody tests to help make a diagnosis of lupus.

Sjogren's Syndrome

During the 85th General Session of the International Association for Dental Research, scientists are reporting that, instead of blood tests and biopsy, saliva can be used to detect primary Sjögren’s Syndrome (pSS), an autoimmune disease which affects about 4 million American, 90% being women. pSS patients are 40 times more at risk than healthy people to develop lymphoma, a fatal lymphocytic cancer.

Gluten Sensitivity / Celiac Disease

If you suspect that you or anyone in your family might have celiac disease, or a gluten-sensitivity, you can ask your doctor to perform a tTG (tissue transgluminase test). Remember, if you have already eliminated wheat or gluten products from your diet, the test results will be negative, even if you have the sensitivity. However, if you have been consuming wheat

products and have the sensitivity, this test will do a better job of picking it up than previous tests.

Testing for fecal antigliadin IgA antibody is another test that some labs provide to help determine if there is a problem with gluten / gliadin consumption.

Angina

Some heart problems are easier to diagnose when your heart is working harder and beating faster than when it’s at rest. During stress testing, you exercise (or are given medicine if you are unable to exercise) to make your heart work harder and beat faster while heart tests are performed. During exercise stress testing, your blood pressure and EKG readings are monitored while you walk or run on a treadmill or pedal a bicycle. Other heart tests, such as nuclear heart scanning or echocardiography, also can be done at the same time. These would be ordered if your doctor needs more information than the exercise stress test can provide about how well your heart is working.

Chronic Fatigue / Fibromyalgia Syndrome

Testing for urinary growth hormone levels could be helpful, as this important hormone is often low in those with CFS / fibromyalgia.

Hypoalbuminemia (A low albumin level)

A test for albumin level is usually included in a metabolic profile, otherwise known as a Chem 16, Chem 20, etc..

Narcolepsy

Polysomnography

Nocturnal polysomnography remains an important part of the evaluation process in the diagnosis of sleep disorders.

Multiple Sleep Latency Test

Once a “normal” night’s sleep has been confirmed and other causes of excessive daytime sleepiness, such as obstructive sleep apnea (OSA) and periodic limb movement disorder (PLMD), have been excluded, a multiple sleep latency test (MSLT) is performed, usually the morning after polysomnography. The MSLT is a similar test, but it measures fewer parameters. The MSLT measures EEG, EOG, chin EMG, and usually heart rate. The patient attempts to take four to five 20-minute naps (depending on the protocol) every 2 hours throughout the day. After these naps, the time it takes the patient to fall asleep (sleep latency) is averaged. Sleep latency usually fluctuates in narcolepsy patients, where it may lengthen, but will most often remain shorter than normal latency.

Cerebrospinal fluid (CSF) hypocretin-1 assessment

It has been found that many (about 90% of narcolepsy-cataplexy subjects) patients with narcolepsy have very low or undetectable levels of hypocretin-1/orexin A in the cerebrospinal fluid.

Hypokalemia / Potassium Need

Potassium level is one of several items tested for in a Chemistry Screen blood test. This test, which goes by various names – Chem 12, Chem 16, Chem 20, or Comprehensive Metabolic Screen is routinely ordered by doctors.

EFA (Essential Fatty Acid) Type 3 Requirement

The omega-3 assay can be used as a marker for both heart disease risk and cellular aging. A kit can be ordered and a small sample of blood taken by finger prick. The sample is sent to a lab and the results sent to you. The test is rather expensive, well over $100. Your doctor may also work with you if preferred to do this lab test.

In the USA and EU the average Omega-3 Index is from 4 to 5%. In Japan, the average diet is high in Omega-3 and the average Omega-3 Index is 9.5%. In the USA, sudden cardiac death rates are about 20 times HIGHER than they are in Japan.

If you are an average American with an Omega-3 Index of 4%, and you want to raise your Omega-3 Index to the goal of 8% (+ 4%), you need to take 25 gram per day weeks of Omega-3. Examples of how to achieve this include:

Diabetes Type II

Determination of hemoglobin A1c is valuable for the follow-up of diabetic patients and useful for measuring a diabetic tendency. While blood glucose monitoring is like a snapshot, hemoglobin A1c testing is more like a full length movie – it provides a view of how your blood glucose level has been doing over a period of two to three months. For people who have not undergone any major changes in their lifestyle or diabetes regimen, hemoglobin A1c tests provide a good assessment of long-term blood glucose control.

For monitoring diabetes, a satisfactory interval for test taking is every third month. It has been shown that well controlled diabetics have a lower incidence of complications. Since costs for treatment of diabetics are high, hemoglobin A1c testing is very cost effective.

Cirrhosis of the Liver

Today, the only way to detect cirrhosis is through a biopsy – where a tissue sample is taken by injecting a needle through the skin into the liver. Biopsy is not entirely risk-free and is very expensive.

VIB researcher Nico Callewaert and his colleagues in the team of Roland Contreras (Dept. for Molecular Biomedical Research, Ghent University) have developed a new method that only requires a little blood in order to detect the cirrhosis stage reliably. In a test group of patients, the researchers succeeded in detecting 70 to 80% of the early liver cirrhoses. Not a single patient was diagnosed incorrectly.

The new test detects changes in the quantities of the various sugars that are produced by the liver, which occur in the transition from fibrosis to cirrhosis. The researchers have been able to measure the sugar changes quite accurately with advanced instrumentation that is already being used in clinical laboratories, but for genetic tests.

The test is now being perfected. Through future collaborations with industry, the researchers hope to arrive at a test that is easy to use and that shows 100% specificity for cirrhosis of the liver. The test could then be used to follow people with chronic hepatitis C viral infection. [8-Mar-2004 Prof. Roland Contreras, Flanders Interuniversity Institute of Biotechnology ]

Gallbladder Disease

The ultrasound uses sound waves to visualize the bile ducts, liver, and pancreas. When gallstones are present, they are seen in either the gallbladder or bile ducts. Little risk is associated with the ultrasound test. The ultrasound may not see gallstones in obese patients, or in patients who have recently eaten.

Increased Risk of Diabetes ll

Determination of hemoglobin A1c is valuable for the follow-up of diabetic patients and useful for measuring a diabetic tendency. While blood glucose monitoring is like a snapshot, hemoglobin A1c testing is more like a full length movie – it provides a view of how your blood glucose level has been doing over a period of two to three months. For people who have not undergone any major changes in their lifestyle or diabetes regimen, hemoglobin A1c tests provide a good assessment of long-term blood glucose control.

For monitoring diabetes, a satisfactory interval for test taking is every third month. It has been shown that well controlled diabetics have a lower incidence of complications. Since costs for treatment of diabetics are high, hemoglobin A1c testing is very cost effective.

Increased Risk of Alzheimer's / Dementia

MRI scans can be used to diagnose Alzheimer’s disease, even before the onset of symptoms of dementia, say researchers.

Alzheimer’s disease is currently diagnosed by a process of elimination as many other diseases cause similar symptoms, furthermore a diagnosis of Alzheimer’s disease cannot be confirmed until after the patient has died by autopsy. However, results of a study by Ranjan Duara and colleagues at the Florida Alzheimer’s Disease Research Center (ADRC) has added to a growing body of evidence which suggests that MRI scans of the brain can be used to diagnose the neurodegenerative disease.

The researchers used a visual rating system to evaluate the extent of atrophy, or shrinkage, present on MRI scans in three parts of the medial temporal lobe of the brain which are vital for conscious memory. They then compared the MRI brain scans of 260 people, which included people with probable Alzheimer’s disease, people with varying degrees of mild cognitive impairment (MCI), and a control group of normal elderly with no symptoms of memory loss. Results showed that by using the rating system they could accurately distinguish those with probable Alzheimer’s disease from those with MCI, and from those in the control group. Furthermore, the scans even enabled the researchers to identify brain atrophy in some participants who did not have symptoms of memory loss at the start of the study, but who went on to develop memory problems several years later. Thus suggesting that MRI scans could enable doctors to identify those who will get Alzheimer’s long before they become symptomatic.

“This study demonstrates that MRI brain scans are accurate enough to be clinically useful, both in diagnosing Alzheimer’s disease itself at an early stage and in identifying people at risk of developing Alzheimer’s,” said Huntington Potter, PhD director of the Florida ADRC.

News release: MRI brain scans accurate in early diagnosis of Alzheimer’s disease. University of South Florida Health. December 18th 2008.

Increased Risk of Stomach Cancer

March 2013 – A quick and simple breath test can diagnose stomach cancer, study findings reveal. Scientists from Israel and China found the test was 90% accurate at detecting and distinguishing cancers from other stomach complaints in 130 patients. The British Journal of Cancer says the test could revolutionise and speed up the way this cancer is diagnosed.

Cancer appears to give off a signature smell of volatile organic compounds that can be detected using the right technical medical kit – and perhaps even dogs.

The science behind the test itself is not new – many researchers have been working on the possibility of breath tests for a number of cancers, including lung.

But the work by Prof Hossam Haick, of the Technion-Israel Institute of Technology, suggests it is a good way to spot stomach cancer.

In the study, 37 of the patients had stomach cancer, 32 had stomach ulcers and 61 had other stomach complaints. As well as accurately distinguishing between these conditions 90% of the time, the breath test could tell the difference between early and late-stage stomach cancers.

The team are now running a bigger study in more patients to validate their test.

Increased Risk of Prostate Cancer

Elevated Prostate Specific Antigen (PSA) levels can be a sign of prostate cancer spread in men with early cancer. However, the PSA test does not distinguish between slow-growing and aggressive cancers. As a result, there are suggestions that prostate cancer may be overdiagnosed and overtreated.

Robert W. Veltri, from Johns Hopkins University (Maryland, USA), and colleagues have developed a new blood test, known as the Prostate Health Index (PHI). It measures three forms of PSA, including pro-PSA, a shortened molecule that is missing a few of the amino acids that make up the PSA protein, and suggested to be a highly accurate form of PSA.

The team studied 71 men who were diagnosed with small, low-grade, and low-stage prostate cancer based on their PSA results. Approximately four years later, 39 had unfavorable biopsy results that signaled a need for treatment. The PHI test was performed on blood samples, banked at the time of biopsy, from all 71 men.

When the researchers combined the biopsy results with the PHI data, they were able to predict 7 in 10 men that might progress, leading them to conclude that: “Measurement of the serum PHI and tissue DNA content at the time of diagnosis are able to predict which men enrolled in an [active surveillance] cohort will ultimately require treatment for [prostate cancer].” [American Association for Cancer Research 101st Annual Meeting 2010]

Stomach Cancer

March 2013 – A quick and simple breath test can diagnose stomach cancer, study findings reveal. Scientists from Israel and China found the test was 90% accurate at detecting and distinguishing cancers from other stomach complaints in 130 patients. The British Journal of Cancer says the test could revolutionise and speed up the way this cancer is diagnosed.

Cancer appears to give off a signature smell of volatile organic compounds that can be detected using the right technical medical kit – and perhaps even dogs.

The science behind the test itself is not new – many researchers have been working on the possibility of breath tests for a number of cancers, including lung.

But the work by Prof Hossam Haick, of the Technion-Israel Institute of Technology, suggests it is a good way to spot stomach cancer.

In the study, 37 of the patients had stomach cancer, 32 had stomach ulcers and 61 had other stomach complaints. As well as accurately distinguishing between these conditions 90% of the time, the breath test could tell the difference between early and late-stage stomach cancers.

The team are now running a bigger study in more patients to validate their test.

Breast Cancer

In the U.S., a novel technology soon may be available to detect the spread, or metastasis, of breast cancer earlier than now possible, according to research presented at the first international meeting on Molecular Diagnostics in Cancer Therapeutic Development, organized by the American Association for Cancer Research.

Since secondary tumors, ignited by spreading malignant cells, and not the primary breast cancer tumor, are the primary cause of cancer death, early detection of metastatic spread is crucial to a woman’s prognosis.

Albert said that the company’s diagnostic tool, which is being evaluated in clinical studies at The University of Texas M. D. Anderson Cancer Center in Houston, can spot one malignant cell in a typical blood sample. A typical sample is 5 milliliters and contains over 2.5 x 1010 cells.

As a biomarker for breast cancer metastasis, cancer cells circulating in the blood system have not been easy to detect and analyze because they are a “needle in the haystack” among the millions of cells in the bloodstream.

However, Albert said that AdnaGen’s technology can detect the “needle” with a specificity of 97 percent (only three “false” positive results in tests of 100 seemingly healthy people).

“Metastasis usually is detected by costly, cumbersome physical methods like computer tomography (CT),” added Albert. “We have seen cases, where our test was positive, when there was still no clinical evidence. But at a careful second look through a CT scan, small metastatic lesions have been detected.”

To produce its diagnostic tool, AdnaGen links an antibody-mix to magnetic beads. This antibody-mix is tailored to home in on specific molecular features, or antigens, of the respective cancer cells.

When exposed to a blood sample, the magnetic antibody-beads capture tumor cells possessing the specified antigens. A magnetic particle concentrator then removes the tumor cells labeled with the magnetic beads, and the cells are then analyzed to identify several gene products, including potential molecular targets for a specific drug.

Using this technology, AdnaGen discovered that the genetic signatures of the breast cancer and its metastases may differ, with the circulating tumor cells reflecting the gene expression profile of the metastases.

When a metastases has been diagnosed, treatments “usually has been chosen according to the features of the primary tumor, neglecting the fact that metastases can differ considerably from them,” Albert noted.

AdnaGen, which is marketing its breast cancer assay (as well as assays for colon and prostate cancer) in Europe, is awaiting the results of a clinical trial before applying for FDA approval to make the test available in the U.S. [Medical News Today 15 Sep 2006]

Endometriosis

Endometriosis is a notoriously difficult condition to diagnose, the conclusion often being reached only after excluding other problems. The presence of endometriosis can only be confirmed through examination of the tissue. Fiberoptic laparoscopic techniques allow a direct look at the problematic tissue. The average age at diagnosis is 37 years, and the majority of cases occur in women between the ages of 25 and 40. Endometriosis is rare before the onset of menstruation and after menopause but not unknown.

Female Infertility

If both the semen analysis and hormone tests are normal, there is also additional testing that your fertility specialist may recommend. These tests include any of the following: