TRF

Abbreviation for thyrotropin-releasing factor.

IL5

A gene on chromosome 5q31.1 that encodes interleukin-5, a cytokine which acts as a growth and differentiation factor for B cells (inducing the terminal differentiation of late-developing B-cells to immunoglobulin secreting cell) and eosinophils, for the latter of which IL5 is a key regulator of eosinopoiesis, eosinophil maturation and activation.

Transferrin

Synonym/acronym: Siderophilin, TRF.

Common use

To assess circulating iron levels related to dietary intake to assist in diagnosing disorders such as iron deficiency anemia or hemochromatosis.

Specimen

Serum (1 mL) collected in a gold-, red-, or red/gray-top tube.

Normal findings

(Method: Nephelometry)

Age	Conventional Units	SI Units (Conventional Units × 0.01)
Newborn	130–275 mg/dL	1.3–2.75 g/L
1–9 yr	180–330 mg/dL	1.8–3.3 g/L
10–19 yr	195–385 mg/dL	1.95–3.85 g/L
Adult
Male	215–365 mg/dL	2.2–3.6 g/L
Female	250–380 mg/dL	2.5–3.8 g/L

Description

Transferrin is a glycoprotein formed in the liver. Its role is the transportation of iron, obtained from dietary intake or RBC breakdown; normally one-third of available transferrin is saturated. Inadequate transferrin levels can lead to impaired hemoglobin synthesis and anemia. Transferrin is subject to diurnal variation, and it is responsible for the variation in levels of serum iron throughout the day. (See monograph titled “Iron-Binding Capacity [Total], Transferrin, and Iron Saturation.”)

This procedure is contraindicated for

N/A

Indications

Determine the iron-binding capacity of the blood
Evaluate iron metabolism in iron-deficiency anemia
Evaluate nutritional status
Screen for hemochromatosis

Potential diagnosis

Increased in

Estrogen therapy (estrogen stimulates the liver to produce transferrin)
Iron-deficiency anemia (the liver produces transferrin in response to decreased iron levels)
Pregnancy (the liver produces transferrin in response to anemia of pregnancy)

Decreased in

(a negative acute-phase reactant protein whose levels decrease in response to inflammation)

(related to malnutrition)

(related to increased loss from damaged kidney)

(related to decreased synthesis in the liver)

(related to a protein-deficient diet that does not provide the nutrients required for synthesis)

Critical findings

N/A

Interfering factors

Drugs that may increase transferrin levels include carbamazepine, danazol, mestranol, and oral contraceptives.
Drugs that may decrease transferrin levels include cortisone and dextran.
Transferrin levels are subject to diurnal variation and should be collected in the morning, when levels are highest.
Failure to follow dietary restrictions before the procedure may cause the procedure to be canceled or repeated.

Nursing Implications and Procedure

Pretest

Positively identify the patient using at least two unique identifiers before providing care, treatment, or services.
Patient Teaching: Inform the patient this test can assist in evaluating for anemia.
Obtain a history of the patient’s complaints, including a list of known allergens, especially allergies or sensitivities to latex.
Obtain a history of the patient’s hematopoietic system, symptoms, and results of previously performed laboratory tests and diagnostic and surgical procedures.
Obtain a list of the patient’s current medications, including herbs, nutritional supplements, and nutraceuticals (see Effects of Natural Products on Laboratory Values online at DavisPlus).
Review the procedure with the patient. Inform the patient that specimen collection takes approximately 5 to 10 min. Address concerns about pain and explain that there may be some discomfort during the venipuncture.
Sensitivity to social and cultural issues, as well as concern for modesty, is important in providing psychological support before, during, and after the procedure.
Instruct the patient to fast for at least 12 hr before specimen collection.
Note that there are no fluid or medication restrictions unless by medical direction.

Intratest

Potential complications: N/A
Ensure that the patient has complied with dietary restrictions; ensure that food has been restricted for at least 12 hr prior to the procedure.
Avoid the use of equipment containing latex if the patient has a history of allergic reaction to latex.
Instruct the patient to cooperate fully and to follow directions. Direct the patient to breathe normally and to avoid unnecessary movement.
Observe standard precautions, and follow the general guidelines in Patient Preparation and Specimen Collection. Positively identify the patient, and label the appropriate specimen container with the corresponding patient demographics, initials of the person collecting the specimen, date, and time of collection. Perform a venipuncture.
Remove the needle and apply direct pressure with dry gauze to stop bleeding. Observe/assess venipuncture site for bleeding or hematoma formation and secure gauze with adhesive bandage.
Promptly transport the specimen to the laboratory for processing and analysis.

Post-Test

Inform the patient that a report of the results will be made available to the requesting health-care provider (HCP), who will discuss the results with the patient.
Instruct the patient to resume usual diet, as directed by the HCP.
Nutritional Considerations: Educate the patient with abnormal iron values that numerous factors affect the absorption of iron, enhancing or decreasing absorption regardless of the original content of the iron-containing dietary source. Patients must be educated to either increase or avoid intake of iron and iron-rich foods depending on their specific condition; for example, a patient with hemochromatosis or acute pernicious anemia should be educated to avoid foods rich in iron. Consumption of large amounts of alcohol damages the intestine and allows increased absorption of iron. A high intake of calcium and ascorbic acid also increases iron absorption. Iron absorption after a meal is also increased by factors in meat, fish, and poultry. Iron absorption is decreased by the absence (gastric resection) or diminished presence (use of antacids) of gastric acid. Phytic acids from cereals, tannins from tea and coffee, oxalic acid from vegetables, and minerals such as copper, zinc, and manganese interfere with iron absorption.
Reinforce information given by the patient’s HCP regarding further testing, treatment, or referral to another HCP. Answer any questions or address any concerns voiced by the patient or family. Educate the patient regarding access to nutritional counseling services. Provide contact information, if desired, for the Institute of Medicine of the National Academies (www.iom.edu).
Depending on the results of this procedure, additional testing may be performed to evaluate or monitor progression of the disease process and determine the need for a change in therapy. Evaluate test results in relation to the patient’s symptoms and other tests performed.

Related Monographs

Related tests include A/G, cancer antigens, CBC, CBC RBC count, CBC RBC indices, CBC RBC morphology, ferritin, iron/TIBC, prealbumin, and total protein.
Refer to the Hematopoietic System table at the end of the book for related tests by body system.

TRF

Acronym	Definition
TRF➣Transfer
TRF➣Tamiya Racing Factory
TRF➣Tribunal Regional Federal (Federal Regional Court; Brazil)
TRF➣Tactical Recognition Flash (UK)
TRF➣Thief River Falls (Minnesota)
TRF➣The Roadster Factory (UK)
TRF➣The Rotary Foundation
TRF➣Time Restricted Feeding (nutrition)
TRF➣Thomson Reuters Foundation (est. 1982)
TRF➣Tandem Repeats Finder (algorithm)
TRF➣Trade Reporting Facility (stock transactions)
TRF➣Teachers' Retirement Fund (various locations)
TRF➣Transportation Research Forum
TRF➣Tuesday, Thursday, Friday
TRF➣Trap Rule File
TRF➣Tutorial Request Form
TRF➣Transferrin
TRF➣Thoroughbred Retirement Foundation
TRF➣Target Redemption Forward (finance)
TRF➣Time Resolved Fluorescence
TRF➣Teacher Report Form
TRF➣The Recycling Factory (various locations)
TRF➣Trail Riders Fellowship (UK)
TRF➣Translational Research Facility (various locations)
TRF➣Tropical Rain Forest
TRF➣Tuned Radio Frequency
TRF➣Terrestrial Reference Frame
TRF➣The Royal Flush (gaming guild)
TRF➣Texas Renaissance Festival
TRF➣T cell Replacing Factor
TRF➣Trident Refit Facility
TRF➣Tetsuya Komuro Rave Factory (band; Japan)
TRF➣Thermal Recovery Facility (energy plant; UK)
TRF➣Tax Retirement Fund
TRF➣Travel Request Form
TRF➣Tibet Relief Fund (UK)
TRF➣Test Result Form
TRF➣Telomere Restriction Fragments
TRF➣Turbine Rear Frame (jet engine component)
TRF➣Treatment Record Form (health care billing)
TRF➣Sandefjord, Norway - Torf (Airport Code)
TRF➣Training Request Form
TRF➣Textbook Revolving Fund
TRF➣Turbine Research Facility
TRF➣Thrasher Research Fund
TRF➣The Rush Forum
TRF➣Tehuti Research Foundation (Greensboro, NC)
TRF➣Technical Reference File
TRF➣Transitional Results Framework
TRF➣Transport Research Facility
TRF➣Technical Replacement Factor
TRF➣Temporary Relocatable Facility
TRF➣Tactical Reconnaissance Fighter
TRF➣Technology Request Form (paper work)
TRF➣Third Revised Forecast (finance)

TRF

TRF

TRF

IL5