Articles on Medical Diseases and Conditions

Entries Tagged ‘tests’

Tests for Allergy

The atopic diseases were originally defined as sensitization based on hereditary predisposition (thus differentiating affected persons from nonaffected persons exposed to the same commonly found antigens) and characterized by immediate urticarial skin reaction to offending antigen and by the Prausnitz-Kьstner reaction. Prausnitz and Kьstner demonstrated in 1921 that serum from a sensitized person, when injected […]

Selected Tests of Interest in Pediatrics

Neonatal immunoglobulin levels. Maternal IgG can cross the placenta, but IgA or IgM cannot. Chronic infections involving the fetus, such as congenital syphilis, toxoplasmosis, rubella, and cytomegalic inclusion disease, induce IgM production by the fetus. Increased IgM levels in cord blood at birth or in neonatal blood during the first few days of life suggest […]

Toxicology

This section includes a selected list of conditions that seem especially important in drug detection, overdose, or poisoning. Treatment of drug overdose by dialysis or other means can often be assisted with the objective information derived from drug levels. In some cases, drug screening of urine and serum may reveal additional drugs or substances, such […]

Biochemical Tests for Congenital Anomalies

Besides giving information on fetal well-being, amniocentesis makes it possible to test for various congenital anomalies via biochemical analysis of amniotic fluid and tissue culture chromosome studies of fetal cells (see Chapter 34). In addition, certain substances of fetal origin may appear in maternal serum. In some cases it is possible to detect certain fetal […]

Fetal Maturity Tests

Tests for monitoring fetal maturity via amniocentesis are also available. Bilirubin levels in erythroblastosis are discussed in chapter 11. Amniotic creatinine assay, amniotic epithelial cell stain with Nile blue sulfate, fat droplet evaluation, osmolality, and the Clemens shake test, alone or in combination, have been tried with varying and not entirely satisfactory results. Most current […]

Pregnancy Tests

Most pregnancy tests are based on the fact that the placenta secretes human chorionic gonadotropin (hCG), a hormone that has a luteinizing action on ovarian follicles and probably has other functions that are not completely known. Serum hCG levels of about 25 milli-international units (mIU)/ ml (IU/L) are reached about 8-10 days after conception. The […]

Tests of Gonadal Function

The most common conditions in which gonadal function tests are used are hypogonadism in males and menstrual disorders, fertility problems, and hirsutism or virilization in females. The hormones currently available for assistance include lutropin (luteinizing hormone; LH), follitropin (follicle-stimulating hormone; FSH), testosterone, human chorionic gonadotropin (hCG), and gonadotropin-releasing hormone (GnRH). Gonadal function is regulated by […]

Prolactin Secretion Abnormalities

Prolactin is another peptide pituitary hormone. It stimulates lactation (galactorrhea) in females, but its function in males is less certain. The major regulatory mechanism for prolactin secretion is an inhibitory effect exerted by the hypothalamus, with one known pathway being under control of dopamine. There is also a hypothalamic stimulating effect, although a specific prolactin-stimulating […]

Pituitary Insufficiency

Body organs affected by stimulatory hormones from the pituitary include the thyroid, adrenals, and gonads. Bone growth in childhood is dependent on pituitary GH. Pituitary failure does not produce a clear-cut syndrome analogous to syndromes produced by failure of pituitary-controlled organs (“end organs”) such as the thyroid. Therefore, pituitary hormone deficiency is considered only when […]

Adrenal Medulla Dysfunction

The only syndrome in this category is produced by pheochromocytomas. Pheochromocytoma is a tumor of the adrenal medulla that frequently secretes epinephrine or norepinephrine. This causes hypertension, which may be continuous (about 30% of patients) or in short episodes (paroxysmal). Although rare, pheochromocytoma is one of the few curable causes of hypertension and so should […]