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 Disorders of iron metabolism are evaluated primarily by : 1. packed cell volume 2. Hemoglobin & red cell count and indices 3. Total iron and TIBC, percent.

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Presentation on theme: " Disorders of iron metabolism are evaluated primarily by : 1. packed cell volume 2. Hemoglobin & red cell count and indices 3. Total iron and TIBC, percent."— Presentation transcript:

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2  Disorders of iron metabolism are evaluated primarily by : 1. packed cell volume 2. Hemoglobin & red cell count and indices 3. Total iron and TIBC, percent saturation, transferrin, and ferritin

3  Total iron-binding capacity (TIBC) refers to the amount of iron that could be bound by saturating Transferrin and other minor iron- binding proteins present in the serum or plasma sample.  Typically, about 1/3 of the iron- binding sites on Transferrin are saturated.  TIBC is determined by adding sufficient Fe+ 3 to saturate the binding sites on Transferrin, with the excess iron removed by addition of Mg CO3 to precipitate any Fe+ 3 remaining in solution.

4  After centrifugation to remove the precipitated Fe+3, the supernatant solution containing the soluble iron bound to proteins is analyzed for total iron content.  TIBC ranges from around 250 to 425 mg/dL.  Transferrin or TIBC is increased in iron deficiency and decreased in iron overload and hemochromatosis.  Transferrin (TIBC) may also be decreased in chronic infections and malignancies

5  Measurement of serum iron concentration refers specifically to the Fe+3 bound to transferrin and not to the iron circulating as free hemoglobin in serum.  The specimen may be collected as serum without anticoagulant or as plasma with heparin.  Oxalate, citrate, or EDTA all are unacceptable anticoagulants as they binds Fe ions.  Early morning sampling is preferred because of the diurnal variation in iron concentration.

6  Specimens with visible hemolysis should be rejected.  Spectrophotometric determinations have been adapted to automated analysis. These procedures generally have the following steps:  Fe+3 is released from binding proteins by acidification, reduced to Fe+2 by ascorbate or a similar reducing agent, and complexed with a color reagent such as ferrozine, ferene, or bathophenanthroline.

7  TS% is an indication of your ability to bind iron and transport it to various sites such as the bone marrow or liver.  The percent saturation “Transferrin saturation”, is the ratio of serum iron to TIBC * 100%.  Normal range is approximately 20% to 50%, but it varies with age and sex  Transferrin saturation is a more useful indicator of iron status than just iron or TIBC alone.

8  Transferrin is a protein capable of combining with and transporting two atoms of iron.  Transferrin is measured by immunochemical methods such as nephelometry.  It is primarily monitored as an indicator of nutritional status.  As a negative acute-phase protein, its concentration decreases in inflammatory conditions.

9  Serum ferritin is often referred to as the body’s place for storing iron.  Ferritin is measured in serum by immunochemical methods, such as (IRMA), (ELISA), and chemiluminescent techniques.  Several manufacturers provide kits for measuring serum ferritin by either manual or automated means.  Ferritin is decreased in iron-deficiency anemia and increased in iron overload and hemochromatosis.  Ferritin is often increased in several other conditions, such as chronic infections, malignancy, and viral hepatitis.

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11  In iron deficiency, the iron level is low but the TIBC is increased, thus transferrin saturation becomes very low.  In iron overload states, such as hemochromatosis, the iron level will be high and the TIBC will be low or normal, causing the transferrin saturation to increase.

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13  Fasting is required for a TIBC test to ensure the most accurate results. This means the patient shouldn’t eat or drink anything for at least 8 hours before the test.  Certain medicines also may affect the result.  These medicines include: 1. Adrenocorticotropic hormone (ACTH) 2. Birth control pills 3. Chloramphenicol 4. Fluorides  Only the doctor will tell if someone need to stop taking any of these medicines or others.

14  Doctors typically order TIBC tests to check for medical conditions that cause abnormal iron levels.  A TIBC test may be ordered along with a serum iron test, which measures the amount of iron in your blood. Together, these tests help to evaluate people suspected of having either iron deficiency or iron overload.

15  It is customary to test for transferrin (instead of TIBC) when evaluating a person's nutritional status or liver function.  Because it is made in the liver, transferrin will be low in those with liver disease.  Transferrin levels also drop when there is not enough protein in the diet, so this test can be used to monitor nutrition.

16  Hemolytic anemia  Iron or lead poisoning  Frequent blood transfusions  Liver damage  In rare cases, high iron levels may be caused by an overdose of vitamins or iron supplements.

17  A high TIBC or transferrin usually indicates iron deficiency  But they are also increased in pregnancy and with the use of oral contraceptives.

18 Questions : 1.What are your impression about serum iron picture ? 2.In your oponion; What is the possible diagnosis of her status ? 3.Explain the possible causes of your judgment ?

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