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A total of 46 chromosomes with 22 matched pairs plus XX for females and XY for males.
Usage.
Diagnosis of chromosome abnormalities leading to Down syndrome, ring 20 syndrome(epilepsy), microphthalmia, other physical or mental retardation, and sex chromosome disorders
such as Turner's syndrome or Klinefelter's syndrome; establishes sex in hypogonadism or unclear
genitalia; part of the work-up for amenorrhea, infertility (male and female), frequent
miscarriages, and other chromosome-related disorders and some leukemias and transitional-cellcarcinoma of the bladder; used in genetic counseling for prospective parents and those with a
family history of genetic disease.
Description.
Chromosome analysis involves karyotyping human chromosomes from a culture of leukocytesfrom peripheral blood. Cell replication of the cultured leukocytes is chemically halted in
metaphase, and microscopic photographs are taken of the chromosomes within the cell nucleus.The chromosome pictures are enlarged, and the chromosomes are paired, sorted, and studied for
symmetry of pairs, number of chromosomes, identification of sex chromosomes, and staining patterns.
Professional Considerations
Consent form NOT required.
Preparation
1. See Client and Family Teaching .
2. Preschedule this test with the laboratory.
3. Tube: Green topped.
Procedure
1. Draw a 10-mL blood sample.
Postprocedure Care
1. Write the date and time of specimen collection on the laboratory requisition.
2. Send the specimen to the laboratory immediately and refrigerate until testing. Testing
To evaluate infertility in women and men (high serum values of LH are related to gonadaldysfunction, and low values of LH are related to dysfunction or failure of the hypothalamus or
pituitary gland); to evaluate hormonal therapy for inducing ovulation; and to evaluate endocrine
problems related to precocious puberty in children.
Increased.
Amenorrhea, anorchia (congenital absence of testicles), endocrine problems related to precocious puberty in children, hyperpituitarism, Klinefelter's syndrome (in prepubertal boys) (such as sex
chromosome disorder), liver disease, menopause, ovarian or testicular failure (primary gonadaldysfunction), polycystic ovarian disease, primary male hypogonadism, Stein-Leventhalsyndrome (polycystic ovarian disease), tumors (pituitary, testicular), and Turner's syndrome
(ovarian dysgenesis). Drugs include anticonvulsants, clomiphene, naloxone, and spironolactone.
Herbs or natural remedies include Unkei-to.
Decreased.
Adrenal hyperplasia or tumor, amenorrhea (pituitary failure, secondary gonadal insufficiency),
Luteinizing hormone (LH), a glycoprotein, is secreted by the anterior lobe of the pituitary glandin response to stimulation by the hypothalamic release of gonadotropin-releasing hormone. LH
plays a critical role in regulation of ovulatory and reproductive function. In women, LH initiates
luteinization in the ovary, and together with follicle-stimulating hormone (FSH) induces
ovulation. A surge of LH in blood levels indicates that ovulation has occurred. In men, LHstimulates the secretion of androgens and increases the production of testosterone. Together with
FSH, testosterone influences the development and maturation of spermatozoa. Luteinizing
hormone levels peak at midcycle in women of childbearing age, surging when ovulation has
occurred. In menopausal women, levels may be up to five times normal levels.
Anencephaly, erythroblastosis fetalis, hemolytic disease of the newborn, hydrops fetalis,
intestinal obstruction, and Rh sensitization.
Increased Lamellar Bodies in Amniotic Fluid.
Respiratory distress syndrome.
Positive Acetylcholinesterase.
Neural tube abnormalities that allow cerebrospinal fluid (which contains acetylcholinesterase) to
leak into the amniotic sac.
Positive Meconium.
Fetal distress.
Decreased Alpha-fetoprotein.
Not applicable.
Decreased Bilirubin.
Not clinically significant.
Decreased Creatinine.
Fetal lung immaturity.
Chromosome Analysis.
Interpretation required.
Description.
Detection of fetal jeopardy or genetic disease and determination of fetal maturity. Amniocentesisis a 20- to 30-minute procedure in which an aspiration of amniotic fluid is taken
transabdominally and is usually performed after week 12 of gestation. In routine analysis,
amniotic fluid is examined for levels of calcium, chloride, carbon dioxide, creatinine, estriol,
glucose, pH, potassium, sodium, protein, urea, uric acid, and culture and for genetic defects,
chromosomal studies, detection of fetal jeopardy or distress (by color, bilirubin), and to measurelung maturity (by L/S ratio) and age (by creatinine of the fetus). Alpha1-fetoprotein is a globulin
protein secreted by the yolk sac and by fetal liver cells during hepatic cell multiplication. The
highest amounts are found during pregnancy and in hepatic cancer. Measurement is usually performed from week 16 to 20 to help identify fetal neural abnormalities, gastroesophageal
atresia, and nephrosis. Chromosome analysis of amniotic fluid cells is performed by examination
of karyotyped cells for genetic abnormalities such as Down syndrome, Tay-Sachs disease, andother inborn errors of metabolism. Amniotic fluid is examined for color and bilirubin level for
detection of fetal jeopardy or distress caused by hemolysis of fetal red blood cells.
Erythroblastosis fetalis occurs when maternal antibodies attack fetal red blood cells, causing fetal
anemia. This occurs when the mother's blood contains the Rh factor that reacts with fetalerythrocyte antigens. The test is usually performed at gestation week 24 or later and can help
determine the need for intrauterine fetal blood transfusion. After the 35th week of pregnancy, the
phospholipid levels of lecithin and sphingomyelin change in a predictable pattern that indicatesthe level of maturity of fetal lungs. Lecithin rises and sphingomyelin decreases as the fetal lungsmature.
6. About 7 – 15 mL of amniotic fluid is aspirated through the spinal needle into a syringe,
and the needle is withdrawn. Use a 20-mL amniotic fluid sample for direct genetic
analysis for the four most common mutations responsible for Tay-Sachs disease.
Postprocedure Care
1. Apply a dry, sterile dressing to the aspiration site.
2. Inject 2 – 5 mL of amniotic fluid into a light-protected (foil-covered or amber) test tube to
test for bilirubin. Inject 5 – 10 mL of amniotic fluid into a sterile, siliconized glasscontainer or a polystyrene container for culture and genetic and other studies (AFP).
Specimens to be transported to another site for testing should be packed in a cool,
insulated container to maintain a temperature of 2 – 5 degrees C. Freezing temperaturesshould be avoided.
3. Obtain the mother's vital signs. Auscultate fetal heart tones for changes from the baseline
value.
4. The mother should rest on her right side for 15 – 20 minutes after the procedure.
5. RhoGAM may be prescribed for Rh-negative mothers.
6. Transport the amniotic fluid specimen to the laboratory immediately and refrigerate.
Client and Family Teaching
1. Empty your bladder immediately before the procedure if gestation is 21 weeks or more.
You must have a full bladder during the procedure if gestation is 20 weeks or less.
2. It is important to lie motionless throughout the procedure. You may experience a strongcontraction with the needle insertion.
3. Chromosome analysis results may take up to 4 weeks.
4. After the procedure, notify the physician for cramping, abdominal pain, unusual vaginal
drainage/fluid loss, fever, chills, dizziness, or more or less than the usual amount of fetalactivity.
5. Inform the client with abnormal genetic findings of choices regarding pregnancy and pregnancy termination. Also refer the client for genetic counseling before future attempts
to become pregnant.
Factors That Affect Results
1. Reject frozen or clotted specimens.
2. Inadvertent aspiration of maternal urine can be ruled out by testing the specimen for
blood urea nitrogen (BUN) and creatinine. Urine BUN is >100 mg/dL, whereas amniotic
fluid is well under 100 mg/dL. Urine creatinine is usually >80 mg/dL, whereas amnioticfluid creatinine is usually ≤4 mg/dL.
3. Nonsiliconized glass containers for routine analysis may result in cell adherence on the
sides of the container.
4. Amniotic fluid testing must be performed within 3 days of collection.
5. Amniocentesis should be performed between weeks 24 and 28 when one is checking for
hemolytic disease of the newborn and Rh sensitization.
6. Falsely low bilirubin levels may result from failure to protect the specimen from light.
7. Specimens contaminated with blood should be tested for fetal hemoglobin to determine
whether the blood is of maternal or fetal origin. Fetal blood contamination results infalsely high bilirubin levels. Fetal or maternal blood will interfere with measurements of
fetal lung maturity and amniotic fluid constituents that are also constituents of plasma,
such as protein, potassium, and glucose.
8. Creatinine levels are affected by maternal creatinine clearance and maternal creatinine
levels. A concurrent maternal serum creatinine should be drawn. Maternal serum to
amniotic fluid creatinine ratio should be about 2:1.
9. Elevated AFP results may be caused by contamination of the specimen with fetal blood.
10. Small and closed neural tube defects may not cause elevated AFP levels.
11. Accurate L/S ratio measurement is not possible if the specimen is contaminated with
blood (fetal or maternal) or meconium.
Other Data
1. Direct karyotyping of placental villi samples obtained by needle aspiration has been
found to yield faster results than amniotic fluid chromosome analysis. (See Chorionic
villi sampling — Diagnostic .)
2. Chromosomal aberration has been found in 4.6% of fetuses in women >38 years of age,
the most common being trisomy 21 (62%), Klinefelter's syndrome (11%), and Edward'ssyndrome (trisomy 18) (11%).
3. For diamniotic twin pregnancies, each amniotic sac should be sampled.
4. Early amniocentesis is feasible from 11 weeks of gestation and can be performed for the
usual indications as an alternative to chorionic villus sampling. Results are available in
less than 1 week using cytogenetic techniques.5. Prenatal cystic fibrosis profile may be performed by polymerase chain reaction (PCR) for
mutations (F508, R553X, g551D, g542X, n1303K, and w1282X).
6. Amniotic fluid neuron-specific enolase is useful as a marker for neonatal neurologic
Thyroglobulin (Tg) Undetectable (NOTE: Tg is only measured after total thyroid ablation todetect recurrent thyroid cancer.)
Usage.
Work-up of suspected thyroid disorder and differentiation of primary thyroid disease fromsecondary causes and from abnormalities in thyroid-binding globulin levels.
Description.
Thyroid function testing involves performing several measurements on one sample of blood.These tests have largely been replaced by the third-generation thyroid-stimulating hormone
assay. Tests included are as follows: Thyroid test: Free thyroxine index — Serum; Thyroid test:
Thyroid-stimulating hormone — Blood and sensitive assay; Thyroid test: Thyroxine — Blood; andThyroid test: Triiodothyronine — Blood. See individual test listings for further description. Many
clients are found to have subclinical thyroid disease as described below, which may or may not be treated. Subclinical hypothyroidism is more common than subclinical hyperthyroidism.
Identification of abnormal growth patterns by serial radiography. Detection of ankylosingspondylitis, congenital abnormalities, fractures, healing fractures, hyperparathyroidism,
infection, joint destruction, osteomalacia, osteomyelitis, osteoporosis, the presence of joint fluid,
rickets, and tumors.
Description.
Specific bones are radiographed in several positions for visualization of the bone from all angles.Kiru et al (2002) found magnetic resonance imaging superior to bone radiography for detecting
bone stress injuries in the early phase of damage.
Professional Considerations
Consent form NOT required.
Precautions
During pregnancy, risks of cumulative radiation exposure to the fetus from this and other previous or future imaging studies must be weighed against the benefits of the procedure.
Although formal limits for client exposure are relative to this risk-benefit comparison, theUnited States Nuclear Regulatory Commission requires that the cumulative dose equivalent to
an embryo/ fetus from occupational exposure not exceed 0.5 rem (5 mSv). Radiation dose to
the fetus is proportional to the distance of the anatomy studied from the abdomen anddecreases as pregnancy progresses. For pregnant clients, consult the radiologist/radiology
department to obtain estimated fetal radiation exposure from this procedure.Preparation
1. Handle injured parts carefully.
2. Shield the client's testes, ovaries, or pregnant abdomen.
Procedure
1. The client is placed on the radiography table in several positions, with a radiograph taken
in each position.
2. The client must lie still for the radiograph.
Postprocedure Care
1. The client remains in the radiology department until it is determined that the films aresatisfactory.
Client and Family Teaching
1. The amount of exposure to radiation is minimal and not dangerous.
2. It is important to stay still during the radiograph.
3. Results are normally available within 24 hours.
Factors That Affect Results
1. Movement results in an unsatisfactory radiograph.
2. Too little or too much exposure results in a radiograph that is too light or too dark and
may need to be repeated for interpretation.
Other Data
1. Wear a lead apron if remaining in the room with the client during radiography.
aminosalicyclic acid, pargyline hydrochloride, phenacetin, phenazopyridine, phenelzine sulfate, phenformin, propranolol (in diabetic clients), and tranylcypromine sulfate.
Description.
Glucose is a monosaccharide formed from the digestion of carbohydrates and the conversion of
glycogen by the liver and is the body's main source of cellular energy. The glucose tolerance test
is most commonly used to aid in the diagnosis of diabetes mellitus. If blood glucose levels peakat higher than normal levels at 1 and 2 hours (after injection or ingestion of glucose) and are
slower than normal to return to fasting levels, diabetes mellitus is confirmed.
Professional Considerations
Consent form NOT required.
Preparation
1. See Client and Family Teaching .
2. Tubes: Gray topped × 6 – 7.
3. Label each tube as shown in the table below (See Procedure 4).
Procedure
1. Begin the test between 7 and 9 AM.
2. Draw a 1 – 4-mL venous blood sample.
3. Intravenous GTT: Inject a standardized intravenous solution of 0.5 g/kg of body weight
of 50% glucose, or 50 mL of 50% glucose intravenously over 4 minutes.
4. Oral GTT: Adults should completely ingest a solution containing 75 – 100 g of glucosewithin 5 minutes.
5. Repeat step 2 at the following precise time intervals after infusion or ingestion of glucose
is started.
6. If evaluating for postprandial hypoglycemia, draw an additional sample at 4 hours.
Postprocedure Care
1. Current administration of medications known to affect the test results should be noted on
the laboratory requisition.
2. Send blood samples to the laboratory immediately or refrigerate them.Client and Family Teaching
1. Eat a high-carbohydrate (200 – 300 g) diet for 3 days before testing.
2. Avoid alcohol, coffee, and smoking for 36 hours before testing.
3. Fast (except for water) for 10 – 16 hours.
4. When possible, drugs affecting results should be stopped 3 – 21 days before the test.
5. Insulin and oral hypoglycemic agents should be withheld the morning of the test.
6. Avoid strenuous exercise for 8 hours before and after the test.
7. Because the test requires multiple blood samples, suggest bringing a book or other quietdiversion to the test because it usually requires a minimum of 3 hours.
8. Alert the client to the symptoms of hypoglycemia and instruct the client to report these
symptoms immediately.
Factors That Affect Results
1. No eating, smoking, or exercise is permitted during the testing period. Caffeine interfereswith the accuracy of the results.
2. Water may be given to help ease the collection of urine specimens.
3. Failure to adhere to a high-carbohydrate diet for 3 days before the test may produce
abnormally increased results.
4. Stresses caused by acute illness, pregnancy, or surgery invalidate the results.
5. Slight increases are normal in clients more than 50 years of age (up to 1 mg/dL per yearfor ages more than 50 years).
6. When the glucose oxidase/peroxidase procedure is used, falsely decreased glucose values
may occur when the client has recently taken acetaminophen or oxycodone.
Other Data
1. This test usually takes 3 – 5 hours.
2. 10 mL of urine for glucose measurement may also be collected at the same time as the
blood samples.
3. The intravenous glucose tolerance testing method is recommended for clients who may
have impaired or erratic intestinal absorption of glucose.
4. The oral glucose tolerance test has been shown to be unreliable for use in the evaluation
of reactive hypoglycemia.
5. In a client with non – insulin-dependent diabetes (type 1), fasting serum glucose levels
may be within normal range, but insufficient secretion of insulin after ingestion of
carbohydrates causes serum glucose to increase sharply and return to normal slowly.
6. If a client develops severe hypoglycemia during the test, draw a blood sample, record the
time on the laboratory requisition, and discontinue the test. Have the client ingest an oral
form of glucose or administer intravenous glucose according to the physician's orders.
7. A 2-hour glucose level is better than a fasting level alone in identifying older adults atincreased risk of major incident cardiovascular events (Smith et al, 2002).
8. A 2-hour glucose ≥11.1 mmol/L increases risk for pr eterm delivery.
Dependent on time and content of last meal. In normal clients, glucose levels return to the fastinglevel (given in these norms) within 2 hours after the last meal.
NOTE: Treatment choice(s) depend(s) on client's history and condition and episode history.
1. Administer subcutaneous or intravenous injection of insulin per sliding scale.Intravenous insulin is typically administered by continuous infusion for panic levels
accompanied by reduced level of consciousness. Hourly adjustments are based onsubsequent blood glucose measurements.
2. Perform hourly neurologic checks.
3. Monitor hourly intake and output.
4. Monitor for hypokalemia as side effect of treatment.
Panic Level Symptoms and Treatment — Decreased Symptoms.
Confusion, headache, hunger, irritability, nervousness, restlessness, sweating, and weakness.
Treatment
NOTE: Treatment choice(s) depend(s) on client's history and condition and episode history.
1. Administer oral form of glucose followed by oral ingestion of carbohydrates. Forneonates or unconscious clients, give IV glucose or IV/IM glucagon.
aminosalicylic acid, pargyline hydrochloride, phenacetin, phenazopyridine, phenelzine sulfate, phenformin, propranolol (in diabetics), tetracyclines, theophylline, and tranylcypromine sulfate.
Herbs or natural remedies include zhi mu (‗know-mother,' Anemarrhena asphodeloides, an herb)
and shi gao (‗stone-plaster,' calcium sulfate, gypsum) taken in combination; xuan shen (‗blackginseng,' Scrophularia ningpoensis, figwort) and cang zhu (‗green- shu/zhu herb,' Atractylodeslancea, var. ovata) taken in combination; shan yao (‗mountain-medicine,' Dioscorea batatas,
potato yam) and huang qi (‗yellow-old 60,' Astragalus reflexistipulus, or A. hoantchy, yellow
vetch) taken in combination; and karela ( Momordica charantia, balsam apple) taken incombination with chlorpropamide. Herbs or natural remedies include teas (decoctions, infusions)
Glucose is a monosaccharide found naturally occurring in fruits. It is also formed from thedigestion of carbohydrates and the conversion of glycogen by the liver and is the body's main
source of cellular energy. Glucose is essential for brain and erythrocyte function. Excess glucose
is stored as glycogen in the liver and muscle cells. Hormones influencing glucose metabolism
include insulin, glucagon, thyroxine, somatostatin, cortisol, and epinephrine. Fasting glucose
levels are used to help diagnose diabetes mellitus and hypoglycemia. A randomly timed test forglucose is usually performed for routine screening and nonspecific evaluation of carbohydrate
metabolism. The American Diabetes Association criteria for diagnosis of diabetes mellitusinclude a fasting plasma glucose level of >126 mg/dL (7 mmol/L).