- Homocysteine- Homocysteine is commonly used as a screen for people at high risk for heart attack or stroke. It may be useful in patients who have a family history of coronary artery disease but no other known risk factors. However, its utility for this purpose continues to be questioned because the role, if any, that homocysteine plays in the progression of cardiovascular disease (CVD) has not been established. Routine screening, such as that done for total cholesterol, is not yet recommended. A physician may also order a homocysteine test to determine if a patient has B12 or foliate deficiency.
- Cardio CRP – This test is useful in assessing the risk of cardiovascular disease. Patients with more than 10.0 mg/L would represent a high cardiovascular risk. Also, persistently elevated levels could represent non-cardiovascular inflammation.
- DHT - is a potent androgen derived from testosterone via 5-alpha-reductase activity. DHT avidly binds to sex hormone binding globulin (SHBG). Deficiency results in incompletely virilized males; this would be supported by an elevated testosterone to DHT.
- Insulin, Free – Free insulin is useful in patients with insulin antibodies to evaluate the relationship between glucose concentration with insulin injections.
- Progesterone – Progesterone is a hormone secreted by the adrenal glands. Decreased concentrations of progesterone are observed in women in the short and inadequate luteal phase of menstrual period. Increased concentrations of progesterone are observed in patients with tumors of the adrenals and ovaries during pregnancy.
- Pregnenolone - Pregnenolone is a precursor to all of the corticosteroids and is of great benefit in both hyperadrenalism as well as hypoadrenalism. Testing for Pregnenolone is helpful in diagnosing a problem in function and secretion of any of the corticosteroids.
- Estrogens:
- Estradiol – Estradiol is the major estrogenic hormone secreted by the ovaries. Measurement of estradiol may by useful in women to assess ovarian function in patients with menstrual disorders, precocious or delayed puberty, and menopause and used in men to assess gynecomastia.
- Estriol – The placenta converts DHEA-S produced by the fetal adrenals to Estriol and other estrogens. Estriol is useful in assessing the fetal adrenals and placenta during pregnancy.
- Estrone - Estrone is primarily derived from metabolism of androstenedione in peripheral tissues, especially adipose tissues. Individuals with obesity have increased conversion of androstendedione to Estrone leading to higher concentrations. In addition, an increase in the ratio of Estrone to Estradiol may be useful in assessing menopause in women.
- Testosterone, Total, Free & Bioavailable - Testosterone circulates almost entirely bound to transport proteins: normally less than 1% is free. The principal transport protein for testosterone is known as sex hormone binding globulin (SHBG) or testosterone-estradiol binding globulin (TeBG). Testosterone measurements are used to assess erectile dysfunction, infertility, gynecomastia, and osteoporosis and to asses hormone replacement therapy. Certain drugs and medical conditions may affect the concentration of Free Testosterone even while the Total Testosterone concentration is within the reference range. The Bioavailable Testosterone is biologically active. Historically, the albumin bound Testosterone was not considered active. The weak Testosterone-albumin bound is weak and quickly dissociates. In men, approximately 40% of the Total Testosterone is albumin-bound; in women, approximately 20% of Total Testosterone is albumin-bound.
- SHBG (Sex Hormone Binding Globulin) - The hormones testosterone, dihydrotestosterone, and estrogens are bound to SHBG. SHBG concentrations are increased with pregnancy and decreased with testosterone and obesity. Changes in SHBG concentrations will influence the total hormone concentration but not necessarily the free/active concentrations.
- A SHBG test is primarily ordered to help evaluate the status of a patient’s androgens (male hormones). With men, the issue of concern is testosterone deficiency, while with women the concern is excess testosterone production. A total testosterone may be ordered prior to or along with a SHBG test, which can be useful in determining whether or not a total testosterone measurement is reflecting the amount of testosterone that is available to the body’s tissues.
- SHBG and testosterone levels may be ordered on an adult male to help determine the cause of infertility, a decreased sex drive, and erectile dysfunction, especially when total testosterone results are inconsistent with clinical signs.
- In women, small amounts of testosterone are produced by the ovaries and adrenal glands. Even slight increases in testosterone production can disrupt the balance of hormones and cause symptoms such as amenorrhea, infertility, acne, and hirsutism. These symptoms and others are often seen with polycystic ovarian syndrome, a condition characterized by an excess production of androgens. SHBG and testosterone testing may be useful in helping to detect and evaluate excess testosterone production and/or decreased SHBG concentrations.
- Albumin - Since albumin is low in many different diseases and disorders, albumin testing is used in a variety of settings to help diagnose disease, to monitor changes in health status with treatment or with disease progression, and as a screen that may serve as an indicator for other kinds of testing. Low albumin levels can suggest liver disease. Other liver enzyme tests are ordered to determine exactly which type of liver disease.
- Low albumin levels can reflect diseases in which the kidneys cannot prevent albumin from leaking from the blood into the urine and being lost. In this case, the amount of albumin (or protein) in the urine also may be measured.
- Low albumin levels can also be seen in inflammation, shock, and malnutrition.
- Low albumin levels may also suggest conditions in which your body does not properly absorb and digest protein (like Crohn’s disease or sprue) or in which large volumes of protein are lost from the intestines.
- High albumin levels usually reflect dehydration.
