FAQ
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| My husband (long term diabetic) has been diagnosed with elevated ammonia resulting in encephalopathy, which was treated at the hospital with Lactulose. He had numerous tests for the initial cause but to no avail. Kidneys, liver function, etc. seem OK. |
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| Increased ammonia levels are primarily the result of liver damage (usually cirrhosis). While the liver is recovering, it is important to reduce the sources of ammonia. Animal protein is the major source of ammonia. Replacing animal protein with soy products can lower this source. It has also been shown that adding zinc supplements to the diet can aid in lowering ammonia levels. Adding bacteria that do not produce ammonia to the intestine can also help. Lactobacillus acidophilus is one such organism. It is found naturally in yogurt and is also available as a dietary supplement. The use of Lactulose helps to lower ammonia levels and is often useful in treating encephalopathy. It is important to consult with your health care provider about such dietary changes, particularly in the case of a diabetic. |
| Is an elevated Bilirubin serious in an adult? |
| An elevated bilirubin is always a concern. However, there are a few things to take into consideration: Bilirubin is the breakdown product of the hemoglobin in the red cells. Through an involved process, bilirubin is eventually excreted in the bile along with bile acids and salts in the lower gut. These biles salts help in the absorption of fat from the diet. Increased levels of bilirubin are most commonly associated with liver disorders, but there are other (very infrequently occurring) causes of elevated bilirubin levels. Among these, the more common disorder is Gilbert's Syndrome (pronounced gill-bear) in which the bilirubin produced in the breakdown process is not excreted normally. The result is an increase of unconjugated bilirubin (bilirubin that is not attached to a carrier molecule that makes it easy for the body to excrete). Gilbert's Syndrome is easily diagnosed and is not a serious problem (an individual with Gilbert's Syndrome dies with the disorder and not from the disorder). It is important to ask "How elevated is it?" - the reference range for total bilirubin is 0.2-1.2 mg/dL, if the value is less than 1.5 mg/dL, an immediate concern is not warranted, but the elevation should be brought to the attention of your health care provider. If the value is greater than 1.5 mg/dL, it is a significant finding and should be discussed with your health care provider as soon as possible. The causes of elevated values are manifold and include the excessive use of acetaminophen (Tylenol), billiary obstruction (gallstones), Grigler-Najjar Syndrome (usually diagnosed in childhood), and Dubin-Johnson Syndrome (a rare genetic disorder that is diagnosed at the neonatal level). Elevated bilirubin levels are indicative of an imbalance, the imbalance may be as simple as dehydration or a serious liver or hematological disorder. The magnitude of the elevation is the guiding factor and your health care provider must interpret the elevation with the physical picture - - - not just one elevated metabolite. |
| On my recent blood test, "SEGS" was low (43), but I couldn't find any reference to SEGS on your website. Could you give me a brief explanation? |
| "SEGS" is short for polysegmented neutrophils, the reference range for neutrophils (48-73% for adults) applies to "segs", "neuts", and "polys". A neutrophil value of 43% really is within the refernce range. |
| Please explain to me the interaction between ESR and C-Reactive protein. My ESR is 13 mm/hr my C-Reactive Protein is 2.40 mg/L. What is this telling me? |
| The Erythrocyte Sedimentation Rate (ESR) is determined by putting blood in a tall small diameter tube and measuring how many millimeters the red cells settle in 1 hour. There are two methods used: Westergren uses anticoagulated blood (with some added citrate solution) in a 200 millimeter tube: Male 0-15 mm/h Female 0-20 mm/h Wintrobe uses anticoagulated blood in a 100 millimeter tube: Male 0-10 mm/h Female 0-20 mm/h The reference ranges vary a little among laboratories, but those above are reliable. About 25 years ago, it was recommended that the Westergren ESR be adopted as the "standard" ESR, however, both methods are still available. Increased sedimentation values are found in individuals with inflammatory disease, e.g. rheumatoid arthritis, infections, and conditions that produce globulins or fibrinogen. ESR values change rather slowly in response to the stimulus. C-Reactive Protein (C-RP) is produced in the liver in response to inflammation anywhere in the body, it is similar to immunoglobulin G (IgG) but does not have any specificity to an antigen. Interleukin-1 and interleukin-6 stimulate the production of C-RP. C-Reactive Protein was discovered in the 1930's and is named for its ability to precipitate a polysaccharide (C-polysaccharide isolated from a bacterium). C-RP levels change fairly rapidly in response to inflamation and infections. Until about 5 years ago, the reference range for C-RP was less than 10 mg/L (1 mg/dL). Now the reference range varies depending upon the proposed use of the test, however, a value of less than 0.3 mg/L is accepted as the upper limit. C-RP is now used as another indicator for risk of heart attack or stroke, when used in this fashion, there is a table used to determine the amount of risk. See this site: http://www.pslgroup.com/dg/ab49a.htm See the article on C-RP on our site: http://www.carbonbased.com/modules/news/article.php?storyid=4 The correlation of increased ESR and increased C-RP was made in about 1935. At that time the interest was concentrated on its correlation with infectious diseases and inflammatory processes. Because ESR and C-RP values increase with infections it is important to have these tests done when you are not "sick". Particularly if the individual had a recent bout with "flu", upper respiratory tract infection, urinary tract infection, etc., the test should be delayed for several weeks. Your results show an unremarkable ESR but an increased C-RP; the C-RP may be due to an infection that was acquired just before the testing was done. However, it is difficult to determine much from just these two test results. |
| I was wondering what 5' Nucleotidase is? And where I would be able to get more info? Also is there a breakdown of Iron, Iron Binding Capacity, Unsaturated Iron Binding Capacity, Total Iron Binding Capacity, Iron Saturation percent? |
| 5' Nucleotidase is an enzyme that breaks down pyrimidine-sugar nucleotides, these nucleotides are building blocks for nucleic acids (DNA and RNA) and are also used in building cell membranes. The enzyme is found in all cells but has its highest concentration in the liver. The reference range varies a bit among laboratories but the upper limit is about 18 IU/L. High levels are associated with hepatobiliary disease, liver tumors, cirrhosis, and obstructions caused by gallstones. The test has limited use, it assists in determining the source of elevated alkaline phosphatase levels. Alkaline Phosphatase is an enzyme that is elevated in liver and bone disorders. If 5' Nucleotidase and Alkaline Phosphatase are both elevated, there is a good correlation with liver problems. If 5' nucleotidase is normal and alkaline phosphatase is high, it is likely that the elevation is due to bone involvement (when bones grow, alkaline phosphatase is high). However, there is now an immunoassay that is specific for alkaline phosphatase from the bone. Furthermore, there are many more useful and specific tests to diagnose liver disease, see the site below: http://www.merck.com/pubs/mmanual/section4/chapter37/37a.htm Iron metabolism is assessed by measuring the: 1. Total amount of iron (50-190 mcg/dL) 2. Amount of iron that can be transported expressed in Total Iron Binding Capacity (TIBC 250-450 mcg/dL), it is an indirect measure of the amount of Transferrin*, the protein that transports iron, in the body. If you subtract the the Total Iron Measurement from the TIBC, that is the amount of Unsaturated Iron Binding Capacity (UIBC) or the additional capacity of the Transferrin that is available to carry more iron. When Total Iron is divided by TIBC (and multiply the result by 100%), it yields Iron Saturation or the Percent Saturation (15-50%). * Transferrin (215 - 380 mg/dL) can be estimated from the total iron binding capacity with the equation: Transferrin mg/dL = 0.70 X TIBC 3. Amount of iron stored is measured as Ferritin (10 - 320 ng/mL) See the Laboratory Testing FAQ #3 on this site. |
| Is a CA-125 level of 35 U.mL anything to be concerned about? The lab report notes it as high (anything under 35 as normal). How often should this test be repeated? |
| You must appreciate how reference ranges are determined and the errors that are inherent in laboratory testing. The reference ranges for laboratory tests are established after performing a large number of measurements on a known population; that is on patients who are known to have the disorder the test is intended to identify and on patients who are known to be free of the disorder. The data are then subjected to a statistical analysis to determine the appropriate cut off points or reference ranges (formerly called "normal ranges" but this description has been replaced with "reference range" or "reference interval"). Most reference ranges include 95% of the healthy population within the range, this means that 5% of the healthy population will be outside of the limits. However, the statistics used to develop the reference ranges also predict how far outside the range the healthy population will vary. These are usually expressed in "standard deviation" (SD) but even common sense will prevail when examining values that are outside of the range. As a consequence of this treatment, some "sick" people will have values within the reference range. The values are a continuum and there are not clear lines of distinction. Reference ranges for tumor markers are a little more difficult to define, for CA-125 the upper limit of < 36 (less than 36) or 0-35 U/mL is specifically based on the absence of ovarian cancer in 99% of healthy postmenopausal women tested. In this range, nearly 45% of women with ovarian malignancy had values that were < 36 U/mL and nearly 40% had values greater than 100 U/mL. Additionally, every test has a range of "error", which is also statistically determined and called the coefficient of variation or confidence limits. The "error" is usually small, on the order of 5% for most tests; however, it can be as high as 40%. In the case of a test with a 5% error, a reported value of 100 means that a repeat of the test will produce a value between 95-105. This again is a statistical definition because that 5% error is achievable 95% of the time. The same statistical treatments used to determine a reference range are used to predict the reliability of a test. However, in the case of tumor markers, a change by a factor of two (double or half) from a previously measured value is considered significant. If an individual were diagnosed with ovarian cancer and, at that time, had a CA-125 value of 97 U/mL is treated (surgery, chemotherapy, radiation, etc.) and a follow up CA-125 is then done 3-6 months later: 1. If the value were 36 U/mL, this would be consistent with good response to the treatment of the tumor. 2. If the value were to remain the same (e.g., 90-110 U/mL), it would imply that the tumor is not retreating. 3. If it were to be perhaps 170 U/mL, it would imply that the tumor is continuing to grow and the treatment is not effective. In the case of CA-125, most laboratories use an upper limit of < 36 U/mL. A value of 36 or 37 would probably not cause concern while a value of 70 is at a level of concern and action. CA-125 is not specific to ovarian malignancy, it can also be found in individuals with lung, breast, and pancreatic tumors. It is found in such non-malignant conditions such as cirrhosis of the liver and pancreatitis. The test is intended as a follow up to monitor disease progression and is usually done every 3-6 months. Every laboratory report value should be examined in the light of the reason for doing the test. A CA-125 measurement should not be performed out of curiosity with no basis for following the treatment of ovarian cancer. Unless you did not read your report correctly, a value of 35 should not be flagged high. Ask for another copy of the report to verify your printed result. |
| What does "Bands, absolute" mean in a CBC blood test? |
| This gives you the total number of immature neutrophils, called bands, expressed as cells per microliter of blood. The white blood cells are classified in five major groups: Neutrophils Lymphocytes Monocytes Eosinophils Basophils The numbers of the different types of cells normally occur in the order given above; the most abundant are neutrophils and the most infrequent are basophils. When a complete blood count (CBC) is performed, the total number of white blood cells (WBC) is one of the reported components. It is expressed in the number of cells in a microliter (mcL or uL, the u represents the Greek letter mu) of blood. The old unit of volume measurement was a cubic millimeter (cmm); there is no practical difference between a microliter and cubic millimeter. The commonly accepted range for the total white cell concentration in a healthy person is between 3.8 to 10.8 thousand cells per microliter. When a CBC is performed, each type of white cell is reported as a percentage of the total white cell count, this is the "differential", the amount of each different white cell present. A typical differential may be: Neutrophils (Polysegmented neutrophils) - 57% Lymphocytes - 30% Monocytes - 8% Eosinophils - 4% Basophils - 1% Neutrophils are a specific classification of white cells having special inclusion of granules, which puts them in the group of granulocytes (cells with grains). They are polysegmented neutrophils, which can cause confusion because some laboratories will report them as an abbreviation such as "segs", "polys", "neuts", etc. Neutrophils have a characteristic shape of the nucleus; it is segmented and looks like links of sausages. However, the human body is an ever changing thing, neutrophils are a collection of young and old cells. The older the neutrophil is; the more segments it has in its nucleus. Among other things, for a granulocyte to qualify as a neutrophil, it must have distinctly identifiable lobules in the nucleus. If the nucleus looks more like a single large curved sausage and not several sausage links, the cell is an early form of a neutrophil and is called a "band" or "banded neutrophil" ("stab" is an old discontinued term for a band). The "absolute" part of your question has to do with reporting the total number of bands in a microliter of blood instead of as a percentage. The value is normally very low, e.g. less than 5% of the total white count, so it would be less than 540 cells per microliter. Bands show up when there is an increased production of white cells such as in response to an infection. Visit this link to get an idea of what a stained blood smear looks like and what a laboratory technologist has to examine when performing a differential. http://www.echt.chm.msu.edu/courseware/blockII/Pathology/InfectiousDisease_3.html |
| Where can I find a list of medical terms? |
| There are many such lists, but this is a useful glossary of medical and scientific terms: http://lpi.orst.edu/infocenter/glossary.html#H |
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