Unit 5 Review Flashcards
Which of the following electrolyte measurements would be of clinical usefulness to the clinician treating patients for pregnancy-induced hypertension?
Magnesium
Which of the following statements best reflects the clinical usefulness for measuring ionized or free calcium in blood?
It is the best indication of calcium status because it is biologically active and tightly regulated by PTH and vitamin D
Which of the following blood drawing tubes is most appropriate for measuring magnesium?
Plain red top with no additives
Which of the following reagents is used to determine the concentration of serum magnesium?
Methylthymol blue
Monitoring intraoperative PTH is useful for:
Surgical management of primary hyperparathyroidism
Blood levels of ionized calcium are sensitive to which of the following?
- pH and temperature
Which of the following additives is preferred when drawing blood samples to measure parathyroid hormone (PTH)?
Potassium (3)-EDTA (K3-EDTA) because PTH is most stable using this additive
Which of the following statements best illustrates the diagnostic criteria for primary hyperarathyroidism?
Detectable amounts of serum PTH concomitant with elevated total serum calcium
Which of the following feedback mechanisms regulate the productions of 1, 25(OH) 2D3?
Negative feedback mechanism associated with circulating levels of calcium and inorganic phosphorus
Which of the following is an effect of increased parathyroid secretion?
Increased intestinal absorption of calcium
Which of the following laboratory results reflects a patient diagnosed with rickets as a result of a dietary deficiency of vitamin D?
Increased serum PINP, increased serum TRAP, and increased serum DPD
Which of the following do calcium, phosphorus, and magnesium have in common?
They all exist as free or ionized forms, bound to proteins and complexes to radicals, e.g. sulfates to form salts
A blood specimen is received in the laboratory from a maternity in the obstetric unit with blood magnesium ordered by the attending physician. The serum magnesium level is 5.0 mg/dL (RI = 1.6–2.6 mg/dL). Which of the following explains the elevated serum magnesium?
The patient is on magnesium sulfate intravenous infusion because she is experiencing preclampsia
Which of the following is considered a significant problem with using biomarkers of bone turnover in the management of patients with osteoporosis in a clinical setting?
The measurements are affected by several preanalytical variables both controllable and uncontrollable
Which laboratory test listed would be clinically useful to the clinician to assess patents with osteoporosis?
Serum NTX-1
Which of the following laboratory results best represents a patent with Paget’s disease?
Decreased urinary hydroxyproline and increased serum alkaline phosphatase
A progressive systemic skeletal disease characterized by low bone mass and micro architertural deterioration of bone tissue, with a consequent increase in bone fragility and susceptible to fracture describes which of the following disorders?
Osteoporosis
Which of the following reagents is used in the colorimetric method to determine the concentration of calcium in serum?
Cresolpthalein complexone
Which of the following is an example of a controllable preanalytical variable associated with specimen collection for bone biomarker testing?
Diet
Pyridinoline, Carboxy, amino-terminal cross-linked telopeptide of type I collagen, and tartrate-resistant acid phosphatase are all examples of which of the following?
Biomarkers of resorption
Which of the following compounds promote osteoclast formation?
1, 25-dihydroxy Vitamin D3
Heat inactivation and chemical inhibiton are two method used to measure which of the following analytes?
Alkaline phosphatase isoenzymes
Measuring RANK and/or RANKL may be clinically useful for assessing which of the following conditions?
Bone fractures
Which of the following instruments can measure calcium, magnesium, and phosphorus in blood samples?
Atomic absorption spectrometer
Biomarkers of bone formation include which of the following?
Osteocalcin
What hormone is produced by the placenta?
- hCG
Pituitary gigantism associated with which of the following?
Growth (GH) excess
Which of the following is the principle estrogen produced by the ovaries and measured to evaluate ovarian function?
Estradiol
Cushing’s syndrome is characterized by which of the following?
ACTH independent
Which of the following laboratory tests provides a valid index of glucocorticoids secretion?
Urinary free cortisol
Diabetes inspidius is characterized by:
Copious production of urine (polyuria)
Which of the following classes of compounds are derived from tyrosine and includes epinephrine, norepinephrine and dopamine?
Catecholamines
Pheohromocytoma is a tumor arising from which of the following?
Neurochromaffin cells in the adrenal medulla
Which metabolite is most often increased in carcinoid tumors?
5-hydroxyindolacetic acid (5-HIAA)
Which of the following is a metabolite of catecholamine?
Vanillylmandelic acid (VMA)
Thyroid hormones are derived from which of the following amino acids?
Tyrosine
The designation of “high sensitivity” for select quantitative serum thyroid stimulating hormone (TSH) tests indicates which of the following?
The test exhibits low analytical sensitivity
A normally functioning thyroid gland is clinically referred to as:
Euthyroid
Which of the following are characteristic of serum hormone binding globulin (SHBG)?
Tightly bound to protein moiety, not biologically active and binds to testosterone
The goal of early detection and treatment of neonatal hypothyroidism is to eliminate?
severe mental retardation associated with thyroid hormone deficiency in early infancy
Which of the following describes the hypothalamic hormones?
They at as releasing hormones on the pituitary
Unconjugated estriol (uE3) is clinically useful for identifying which of the following?
a fetus with Down syndrome
Which of the following hormones is useful in identifying women with ectopic pregnancies or abnormal intrauterine pregnancies?
Human chorionic gonadotropin
Oxytocin and antidiuretic hormone (ADH) are hormones that are released by the:
Posterior pituitary
In the thyroid gland, which of the following is described as the secretory unit?
Follicle
Pituitary secretion of ACTH is inhibited by elevated levels of:
Cortisol
Tetraiodothyronine describes which of the following compounds?
T4 (thyroxine)
Which of the following is described as a smooth muscle stimulant and vasoconstrictor?
Serotonin
Which of the following is the principle method used to measure hormone levels in blood in many clinical laboratories?
Immunoassays
Once produced, the thyroid hormones are stored as thyroglobulin in which of the following:
Colloid
In a patient with suspected primary hyperthyroidism (Graves’ disease), one would expect the following laboratory serum results: total T4__________ FT4________. And TSH________.
Increased, increased, decreased
Free thyroxine assays measure which of the following?
Only the unbound thyroxine level
Thyroid peroxidase autoantibodies are most sensitive for detecting which thyroid disorder?
Autoimmune thyroid disease (Hashimoto’s thyroiditis)
3, 5, 3’-triodothyronine is characterized as which of the following?
The most potent thyroid hormone
A patient with Addison’s disease would present with which of the following?
Low blood sodium, high blood potassium levels
Mini, little and big are all descriptors for which of the following peptides?
Gastrin
Which of the following is the primary physiological role of secretin??
Stimulate the pancreas to secrete an increased volume of juice with high bi carbonate content
The structure of cholecystokinin (CCK) is described as:
Linear polypeptide with multiple molecular forms
Which of the following compounds key physiological action includes stimulation of insulin secretion in the presence of hyperglycemia and increasing intestinal fluid and electrolyte secretion?
Gastric inhibitory polypeptide
Which of the following represents two primary functions of the GI tract?
Assimilation of nutrients and elimination of waste
Transmural inflammation is associated with:
Crohn’s disease
A gastrinoma is classified as which of the following?
Neuroendocrine tumor (NET)
Which of the following GI disorders is characterized by a modified gut immune function?
Celiac disease
Which of the following cells contain cholecystokinin (CCK)?
I cells from the upper small intestinal mucosa
Which of the following laboratory analytes is tested from a patient with suspected lactose intolerance?
Glucose
Which of the following is test(s) are clinically useful for assessing patients with possible mucosal blood loss?
Serum iron and total iron binding capacity (TIBC)
Which of the following is a useful clinical laboratory test for bile salt malabsorption?
Measurement of 7a-hydroxy-4-cholesten-3-one
Which of the following clinical laboratory tests is useful for diagnosis of peptic ulcer disease (PUD)?
Serum measurement of IgA, IgG, and cytotoxic-associated gene A (CagA)
A patient with suspected protein-losing enteropathy (PLE) would have which of the following laboratory results?
Fecal clearance of Alpha-1-antitrypsin
Which of the following GI peptides relaxes smooth muscles of gut, blood and genitourinary system; increases water and electrolyte secretion and stimulate the release of hormones from pancreas, gut, and hypothalamus?
Vasoactive intestinal polypeptide
Which of the the following statements is correct regarding glycocholic and taurocholate acid
They are bile acids synthesized in the liver
Which of the following test results are correct for a patient with Zollinger-Ellison syndrome?
Elevated serum gastrin, increase in basal gastric acid output
The cutoff point for fasting serum glucose in the lactose tolerance test is > 30 mg/dL (>1.7 mmol/L). Which of the following is the correct interpretation for a patient whose fasting serum glucose is <20 mg/dL (<1.1 mmol/L)?
The pateint is lactose intolerant
The consumption of nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin can lead to which of the following?
Helicobacter pylori disease
Which of the following laboratory results is consistent with with protein-losing enteropathy (PLE)?
Hypoalbuminemia
Scurvy is a disorder caused by a deficiency is which of the following?
Vitamin C
Vitamins A, D and K are classified as:
Fat-soluble
Vitamin B12 is also named?
Cyanocobalamin
Which disorder is associated with vitamin B1 (thiamin) deficiency?
Beriberi
A deficiency of vitamin K (menaquinone) can result in which of the following?
Increased clotting time
The term associated with indirect methods for assessment of vitamin status is termed:
Functional assays
Retinol is formed from which of the following vitamins?
Preformed vitamin A
Insufficient amounts of vitamin A can lead to degenerative changes to the cornea, which leads to poor dark adaption, or night blindness, also known as:
Nyctalopia
Vitamin D deficiency leads to which of the following conditions?
Rickets
Which of the following functions as a chain-breaking antioxidant and is a pyroxyl radical scavenger the protects LDL and polyunsaturated fats in membranes from oxidation?
Alpha-tocopherol
Vitamin E toxicity has been associated with which of the following?
An affliction of premature infants who have been exposed to high oxygen therapy and later developed retinopathy of prematurity (formerly retrolental fibroplasias)
A direct assay for measurement of plasma phylloquinone is useful to assess:
Vitamin K status
Decreased serum levels of vitamin B12 and folic acid are seen in patients with which of the following?
Sprue
A pateint with megaloblastic anemia would show which of the following?
Decreased vitamin B12, decreased folic acid
An individual who consumes massive amounts of vitamin C may develop kidney stones consisting of:
Oxalic acid
Coenzyme A (CoA) contains which of the following?
Pantothenic acid
Changes in vitamin B12 are most dramatic in tissues with the greatest rate of cell turnover because:
Deficiencies result in impaired DNA synthesis in any cell where chromosomal replication and division takes place
Three natural forms of vitamin B6 are:
Pyridoxine (pyridoxol) (PN), pyridoxamine (PM), and pyridoxal (PL)
A patient with presents with the following symptoms: loss of appetite
generalized weakness
abdominal pain and vomiting
bright red tongue (glossitis)
skin rash (casal’s necklace)
Which of the following is associated with these symptoms?
Pellagra
Measurement of vitamin B12 concentration in serum using an immunoassay is an example of which of the following?
Direct assay
Which of the following is described as a nervous system ailment because of a deficiency of thiamine?
Beriberi
Rickets in children of osteoporosis in adults can be minimized through dietary supplementation with which of the following?
Vitamin C, calcium and phosphorus
Pellagra is associated with a deficiency of which of the following vitamins?
Vitamin B3
Niacin is converted to which of the following two cofactors?
Nicotinamide- adenine dinucleotide and nicotinamide-adenine dinucleotide phosphate
Which vitamin is a component of two redox coenzymes?
Vitamin B2
