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Thursday, September 23, 2010

3.3g Blood Testing Groups & Interpretation

Physician's Notebooks 3  - http://physiciansnotebook.blogspot.com - See Homepage

(Continues Chapter 3, Physician's Notebooks 3)
3g Blood Test Groups/Interpretation/Affect of Diet & Environment
Update 01 Aug. 2021
Blood Tests Groups Discussed Below
The following descending shows contents in order of appearance for using search & find or scrolling.

Inflammation Markers
Lipid Profile
Diabetes Mellitus
Kidney Function & Nitrogen Metabolism Tests
Electrolytes and Acidity/Alkalinity (pH) of Blood
Liver Function Tests and Pancreas Inflammation
Cardiovascular Disease Blood Tests
Bone Metabolism Tests
Tests for Hormones Relating to Aging and Stress
Endocrine Disease
Toxic Metals
Infection Tests
 Cancer Markers like PSA
Vitamins 

Inflammation Markers show an inflammatory process which means irritation of tissues either from trauma, toxin or infection. These markers are the RBC sedimentation rate, aka BSR or ESR, which is the length-height of a standard tube sediment (settled to bottom) RBC column after 1 hour; the WBC count, whose name tells all, and the C-Reactive Protein (CRP, which is based on rise of a serum protein that reacts with bacterial capsule). The CRP increases in acute and chronic disease and in USA and Japan is reported in milligram per deciliter (mg/dL) or in other countries in mg/Liter. It may rise in infection, inflammatory disease or cancer. Serial CRP is used to monitor healing and improvement, and cure. It is useful as part of screen for disease inflammation and when it is low indicates an absence of inflammation. It is a risk factor in coronary heart disease and then reported as “high-sensitivity CRP” or hsCRP with <1 mg/L low-risk and >3 mg/L high-risk for coronary heart disease.

Lipid Profile
Interest is on total cholesterol (TC), the low- and high-density lipoprotein cholesterol (LDL-C & HDL-C), and triglyceride (TRG or TG). The key test here is the LDL- cholesterol. Its finding over 100 mg % is bad; under 60 mg % is very good. Together the tests make up “lipid profile” a.k.a "lipid screen" whose results predict risk for clogged artery in heart and brain. It is a key to healthy longevity by warning of high-risk and motivating to change eating and lifestyle in healthy direction. Lipid profile should start at early age (Convenient in newborn or anytime a child is hospitalized) since early detection is the most effective preventive. Bad lipid profile suggests you reform your eating toward a low-fat, lower calorie diet and take a lipid-lowering drug like one of the Statins.
   The TC, LDL-C, HDL-C and TRG  are the key tests but recently the Apolipoprotein A-1 and B-100 (Apo A-1 & Apo B-100) are suggested as lipid risk factors but are not routine. Note that Apo B-100 shows direct risk (higher risk for higher level) while Apo A-1 shows opposite (lower risk, higher level). Ratios are also used to determine relative risk: LDL-C/HDL-C & Apo B-100/A-1 ratios.
Note affect of high banana intake (3 a day for several days): I discovered it ups the TRG. My usual TRG ranges from 30 to 70 mg% but after a month of heavy banana intake as a remedy for constipation, the TRG upped to above 100.

Diabetes Mellitus (Commonly, just diabetes)
  Blood Glucose, blood insulin and glycosylated hemoglobin Hgb A1c diagnose and monitor diabetes mellitus (DM). More than with usual blood chemistry, the blood glucose diagnosis depends on blood sample being drawn after overnight fast. Abnormal low is hypoglycemia and high is hyperglycemia. The Glycosylated Hemoglobin (expressed as percent of total hemoglobin) gives idea how long a diabetic hyperglycemic state has existed. The percent value will vary in proportion to the average level of plasma glucose over the 120-day lifespan of the Red Blood Cell. It provides an index of diabetic blood glucose levels over previous 6 to 12 weeks, which, for a diabetic, is a measure of control of blood glucose by insulin injection or oral med. Also it can pick up diabetes when a single blood sample has a normal plasma glucose.
   In diabetes, an elevated plasma or serum glucose to 140 mg% is seen in early stage. Above 140 is more serious. Borderline glucose should be referred for glucose tolerance test, which is gold standard of diagnosing diabetes. When the test is done in hospital or clinic, blood plasma should be used for sample; with portable machine, use whole-blood glucose, which is 10% lower.

Kidney Function & Nitrogen Metabolism Tests
Blood urea nitrogen (BUN) and creatinine (Cr) are end products of nitrogen metabolism. The BUN and Cr are used to measure kidney function and diagnose kidney failure leading to dialysis. The BUN/Cr ratio is used to differentiate a high BUN due to bleeding in GI tract or state of cardiovascular shock from a high Creatinine that may occur in absence of kidney disease due to muscle trauma, muscle disease or heavy eating red meat. The BUN/Cr ratio in chronic renal failure or with normal kidney function is about 10. But with GI bleeding or shock state from other causes, the BUN/Cr will be >12 and may be >15, and in such case, the high BUN cannot be used to diagnose kidney failure. Creatinine is a better guide in kidney failure, but it must be controlled for meat-eating and muscle trauma, which give high Cr. From the Cr, the Glomerular Filtration Rate (Gfr) is computed. Its lowering is a warning for renal failure and eventual dialysis.
Uric Acid also rises with failing kidneys but is mostly used in diagnosis of hyperuricemia (high-uric acid in blood) and in gout. Normal UA is higher in men than in women. Regardless of gender, UA >10 mg% is dangerous marker not only for uric acid kidney stone but also for hypertension and other causes of cardiovascular mortality. 

Electrolytes and Acidity/Alkalinity (pH) of Blood
   Measurement unit in U.S.A. is mEq/L serum (In other parts of the world it is mMoles/L). Includes sodium (Na+), chloride (Cl), potassium (K+), bicarbonate (HCO3), magnesium (Mg2+). The pH measures acidity/alkalinity. As a screen for good health the most important electrolyte is serum K+. It is a useful marker of the adrenal cortex, being high in adrenal cortical failure (Addison’s disease, suffered by late US President JFK) and low in hyper-adrenal state (overproduction of adrenal hormone cortisone, use of steroid drugs). It is also useful for one taking certain diuretics for heart failure or hypertension because of risk of low-K from chronic thiazides diuretic treatment. Low-K in someone with hypertension but not on diuretic suggests endocrine gland abnormality as cause of the hypertension. False high-K is frequent when blood sample is left standing or handled roughly or when tourniquet applied too strongly to arm for blood drawing. It is due to trauma to RBC and liberation of high intracellular K into the blood serum.
  A borderline low blood magnesium ion (Mg2+) is not rare in a seemingly healthy person. Almond nuts have lots of Mg2+. 

Liver Function Tests and Pancreas Inflammation
Bilirubin is the yellow liver pigment of bile. It is measured as total bilirubin (TB), and is divided into direct (DB) and indirect (IB) bilirubin. Jaundice occurs when TB rises; it starts with deep amber urine with yellowing eye whites. In youth it means hepatitis; in oldster, especially alcoholic drinker it is sign of cirrhosis or cancer. Obstructive gall bladder or liver disease makes high bilirubin of direct type and typically darkens urine and makes the feces a light-clay color. A high indirect Bilirubin occurs where many RBC are destroyed (malaria and other hemolytic anemias). Pure Indirect Bilirubin elevation does not discolor urine or feces.
  Observing your urine and feces for color is useful: A colorless or light clay gray feces with deeply amber or brown urine means obstructive jaundice due to stones in gallbladder or liver ducts or to cancer there. (It may be observed at an early stage of liver disease when skin jaundice has not yet appeared). A normal color feces and urine with skin jaundice suggests infection like Malaria or other cause of hemolysis (break up) of red blood cell.
   Protein is produced in liver from amino acids. The total protein blood test is split into albumin and globulin expressed as the A/G ratio. Albumin low value is sign of under-nutrition or liver damage. It may be a cause of ankle swelling because the albumin molecule holds water in the blood vessels and, when it gets low, the water leaks out of the veins, especially in the feet due to gravity effect. Globulin is a protein involved in immune function, so it is elevated in hyper-immune state and shows low value with defect in immunity.
   Alanine aminotransferase (ALT, formerly SGPT) and aspartate aminotransferase (AST, formerly SGOT) go into blood plasma and are reported from the serum when liver cells get damaged, so high ALT and high AST are signs of liver cell damage from infection or poisoning. Of the two tests ALT is more specific for liver disease because AST can be elevated by heart and skeletal muscle disease or trauma. The height of the rise indicates extent of liver damage. It rises into thousands-units in severe acute hepatitis, and the test, along with gamma-glutamyl transferase (GGT) is good monitor of hepatitis and also for alcoholic liver damage.
There are other liver function tests but the above are best. As screens, they are useful to a person worried about liver damage because he or she may be taking (or have taken) medication or because of work in occupation with high risk for liver damage (high-dose acetaminophen (Tylenol often combine with opioid in USA) oil, coal and other hydrocarbon industry, painter). Also for one worried about the effect of his alcohol drinks on liver.

Pancreatitis is diagnosed by high Amylase, the enzyme made by non-insulin pancreas cells, it functions to digest sugars in small intestine.
By the way - the suffix "-ase", pronounced "aze" means an enzyme produced in cells and released to the blood in cell damage, e.g., creatine-phosphokinase, or CPK when heart muscle cells are destroyed in a coronary artery obstruction heart attack.

Cardiovascular Disease Blood Tests
Two cardiac muscle proteins Troponin and Creatine Kinase (CK, formerly Creatine PhosphoKinase, or CPK) are important diagnosing acute myocardial infarction (AMI). Cardiac specific troponin I (cTnI) is best test for heart muscle damage of Acute Myocardial Infarction (Heart attack from coronary artery blockage). Its elevation may be detected as early as 12 hours after a coronary artery blockage and the height and prolongation of its rise are predictive for recovery or death. The CK shows a similar rise and fall but it also rises in many skeletal muscle diseases and after exercise. The cardiac specific fraction of CK is CK-2 or CK-MB and is the only CK fraction that should be relied on for heart specificity.
   Most recently the B-type Natriuretic Peptide (BNP) has become a blood test to discover early heart failure before it is obvious, for example with mysterious ankle swellings or with deep vein thrombosis and multiple small pulmonary emboli. A normal BNP rules out increased pressure values inside the heart but mildly elevated BNP is frequent without overt heart failure.  
   Also CRP blood test for risk-factor determination. (See CRP) and  homocysteine test for increased coronary heart disease risk.

Bone Metabolism Tests
   Calcium (Ca) and inorganic phosphorus (IP) are tests for parathyroid gland function and calcium and vitamin D nutrition and bone metabolism. The parathyroids are several small glands located alongside thyroid gland, low in neck front. They produce parathormone (PTH). Its effect is to cause a rise in plasma calcium ion (Ca2+) and a drop in Inorganic Phosphorus (IP). Sign of hyperparathyroidism is high PTH and Ca and a low IP. Oppositely, a low PTH and Ca and a high IP is a sign of hypoparathyroidism. An isolated high Ca is not infrequently a sign of metastasis in cancer to bone; also sarcoidosis can cause isolated high Ca. And if one runs across an apparently healthy boy with a high blood test Ca2+, it probably is a case where a ‘soccer mom’ (Fanatic, health oriented mother) has socked her boy with too much vitamin D. The Vitamin D3, 1,25-dihydroxy blood test checks for vitamin D deficiency or overdose, which may be a cause of high or low Ca or IP. Also it may be a sign of Ca deficiency. It should initially be checked as part of parathyroid/Ca/Bone Metabolism tests. Finally, include Magnesium-2+ ion. It is often oppositely abnormal to Calcium-2+.

Effect of Calcium and vitamin D intake on blood test Ca2+ and on Parathyroid Hormone (PTH) test level: Several years ago I was taking Ca carbonate, 500 mg, with vitamin D, 0.250 microgram 3 times a day to slow or prevent osteoporosis. And I noted it upped my blood Ca2+ from c.8.8 up to 9.2 (averages). I became worried about this because calcium and vitamin D intake elevating serum Ca has been reported to up atherosclerosis so now I take my calcium and vitamin D once a day only.

Tests for Hormones Relating to Aging and Stress
Female or male gonad sex hormone – estradiol (E2) and testosterone (TE) are produced in women or men in ovary, testes and adrenal cortex under stimulation of pituitary follicular stimulating hormone (FSH) and luteinizing, hormone (LH). A feedback results in rhythmic rise and fall of E2 and TE and is connected to sperm release and ovulation. The low E2 and low TE is seen in old women and very old men, each feeds back to stimulate anterior pituitary gland cells to over-produce FSH and LH. Testing for the sex hormones can evaluate aging in men and women with view of treating it with sex hormone therapy.
   Free hormone test refers to hormone that is free from its usual combination with a carrier protein (It is not free of charge; au contraire, very expensive). The usual test for hormone in blood measures its combined state with carrier protein. When genetic condition is suspected, it is useful to get the free hormone together with the usual combined hormone test because a high free hormone may be the only indication of a hyperglandular condition (cf. a form of hyperthyroidism with normal usual blood thyroid hormone test).

Endocrine Diseases: The thyroid gland is tested by T3, T4 and TSH tests. T3/T4 are the closely related thyroid hormones whose excess gives hyperthyroidism, the pop-eyed, neck goiter, hyper personality disease; and T3/T4 deficiency gives hypothyroidism with sleepy fat face and thickened skin, and general dull personality. TSH is thyroid stimulating hormone from the anterior pituitary at base of brain. When it is high that means tumor or over-activity of the anterior pituitary and causes secondary hyperthyroidism and symptoms of increased pressure in brain. When it is low, it may mean primary pituitary failure. Be careful interpreting borderline low thyroid tests (slightly low TSH and slightly low T3/T4); it is normal and probably beneficial in old age and should not be treated with thyroid pills as it often is by inexperienced doctors. Any abnormality of thyroid blood tests should have endocrinologist consultation.
   Parathyroid gland effect, mentioned above here, is dealt with also in Mineral chapter of Notebooks 2 under Calcium. It is stimulated by low Ca2+ and inhibited by high Ca2+ in blood. Primary hyperparathyroidism is due to tumor or overactivity of the gland and shows high PTH, high Ca2+ and low inorganic phosphorus (IP). The PTH blood test is an important part of the bone metabolism blood test screen for aging osteoporosis as discussed in the Minerals chapter.
   Adrenal cortex gland test is the blood cortisol level. It is hard to interpret because very sensitive to even minor stress. Ideally the test should be measured from blood sample taken 8 to 9 AM after lying down quietly for 30 minutes. A high value means hyper-adrenalism (Cushing disease or syndrome) a low value is from Addison disease. But, as with thyroid gland, be very careful interpreting low cortisol levels. Especially in old age mildly low levels are normal and possibly beneficial. Serious low cortisol disease should show high K+ test (hyperkalemia) and changes on EKG that go with the hyperkalemia. Again, an endocrinologist should be consulted. The adrenal medulla (central gland) releases excess epinephrine and its products, in the adrenal tumor, pheochromocytoma, with shockingly high blood pressure sudden spiking elevations and severe headache.

Toxic Metals.
 Aluminum and iron are important for Alzheimer or Parkinson Disease; mercury for Minamata disease and “Mad Hatter” syndrome, and city dweller needs to check his blood lead (Plumbum, or Pb) because of the Pb in big city water pipe. Painter, in addition to Pb should check blood cadmium and mercury, or Hg. And health store faddist should get thallium blood test. These tests sometime require preparation so one should seek out clinical lab experienced in the testing.

Infection Tests
Involve the various microorganisms - virus, bacteria, fungus and yeasts, tiny worms, and protozoa like those causing malaria. The rapid tests involve scrapings and smears from skin, and cerebrospinal and joint fluids, and also urine. Although often not blood tests, it is convenient to group all infection tests here.
   Certain words are useful for lay readers. Thus, bacteria smears may be reported to show cocci (perfect circle dot; singular "coccus") and these may be single or may be single linked chains, streptococci, or bunches, staphylococci. Rod-like bacteria are bacilli (singular, bacillus) and spiral motile bacteria are spirochetes (Usually syphilis).
Bacteria get diagnostically divided according to certain staining techniques; thus, the Gram stain divides gram-positive and gram-negative cocci and bacilli; the acid fast stain divides acid-fast bacteria (AFB, usually tuberculosis) from non acid-fast (AFB negative, AFB positive, or non AFB, usually benign bacteria that may be mistaken under microscope for TB). These micro slide tests can be done quickly and therefore are useful but not always highly accurate. The most accurate tests are by culture which may take days or by special antibody testing which is expensive and not often available. Finally, the PCR (polymerase chain reaction) is a highly accurate test. It identifies the DNA of an organism and can be done on blood but takes days and is only available in advanced infectious disease labs.
   While mentioning tuberculosis, the PPD, or Mantoux, skin test is used (mainly outside USA). It is a preparation from killed TB bacteria injected under the skin, often just above the palmar aspect of one’s wrist. If one has has had TB infection in the past it shows positive with a red, elevated wheal after 48 hours. It does not necessarily mean active TB but it does tell the tester that the positive test patient will not benefit from a BCG TB immunization, and a negative test rules out TB as a cause of one’s illness. This is form of skin testing also used in many esoteric semi-infectious diseases like sarcoidosis.
 Antibody/Antigen Titer tests (Hepatitis virus groups, Widal test for typhoid, syphilis, HIV-AIDS and lupus or LE tests) may be key in infectious diagnoses. Except for the Widal test I have not included them in my list of lab values. They are under the specific diseases.


Cancer Markers like PSA
Cancer markers are useful to follow the progression of a cancer case. The most important and useful blood test is prostate specific antigen (PSA) as a screen and prognostic test in prostate cancer. It is usually reported as single unit value - ng/ml -  but recently more accurately for cancer prediction it is reported as velocity of rise and/or related to mgm size of the prostate gland as determined by ultrasound. It is discussed in the prostate chapter. Other cancer blood tests have not proved out as accurate screens but can be useful to follow the progress of a known cancer, its response to treatment, and especially to detect recurrence.
The beta sub unit of human chorionic gonadotropin (hCG) predicts a type of cancer in nonpregnant women and the elevated alpha-fetoprotein test predicts endodermal tumors of ovary. 

Vitamins  
   The vitamin blood levels are important in a general nutrition and aging checkup - especially folic acid and B12. These are mentioned under individual vitamins.

END OF CHAPTER; Next, Blood Test Reference Values List. Click



1 comment:

Joe Root said...

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