Disorders of Iron, Porphyrins and Hemoglobin MLAB 2401: Clinical Chemistry Keri Brophy-Martinez

Iron Deficiency Iron depletion Diminished total body iron stores Functional iron not effected Advanced iron deficiency = ANEMIA Iron Deficiency Anemia(IDA) absolute iron deficiency Anemia of Chronic Disease(ACD) functional iron deficiency

Iron Deficiency Populations affected Children Young women/Expectant women Elderly

Iron Deficiency Anemia Decreased hemoglobin production due to decreased total body iron content Causes of IDA: Increased demand pregnancy Increased loss Menstruation GI bleed Nutritional deficiency Malabsorption Crohn’s or celiac disease Intestinal parasites

3 Stages of IDA Stage 1 : Iron DEPLETION Decrease in storage iron (ferritin decrease) No anemia RBC morphology normal Stage 2: Iron-deficient Erythropoiesis Decrease in iron for erythropoiesis Decrease in ferritin, serum iron Increased TIBC No anemia: RBC slightly microcytic, no hypochromia Stage 3 : Iron DEFICIENCY Decrease in hgb, ferritin, serum iron Decrease in peripheral tissue oxygen delivery Increased TIBC All lab tests abnormal Microcytic, hypochromic anemia

Iron Deficiency Anemia Lab Features Microcytic, hypochromic anemia Anisocytosis, poikilocytosis Total iron and ferritin decreased TIBC increased

Anemia of Chronic Disease Decreased hemoglobin production due to decreased amount of free iron Also known as anemia of chronic inflammation Decreased bone marrow erythropoiesis

Anemia of Chronic Disease Lab features Iron, TIBC decreased Ferritin increased

Iron Overload Syndromes HemochromatosisHemosiderosis Hereditary disorders of iron metabolism Hemosiderin is deposited within cells and interstitial fluid Primarily effects liver, heart, endocrine glands Irreversible Secondary/acquired iron accumulation Hemosiderin is deposited in cells only No tissue damage Reversible

Hemochromatosis Characterized by an increased rate of absorption of iron Excessive iron deposits in organs, tissues, and interstitial fluid Patient develops bronze color in the tissues Total iron, percent saturation increased TIBC decreased

Iron Status in Disease States ConditionSerum IronTransferrinFerritin% Saturation IDADecreasedIncreasedDecreased Iron OverdoseIncreasedDecreasedIncreased HematochromatosisIncreasedSlight DecreaseIncreased MalnutritionDecreased Variable Chronic anemiaDecreased Normal/decreasedNormal/increased decreased Acute liver diseaseIncreasedVariableIncreased

Hemoglobin Disorders Refer to Hematology notes Hemoglobinopathies Thalassemia Lab values Increased ferritin

Porphyrin Disorders= Porphyrias Enzyme deficiencies resulting in overproduction of heme precursors in bone marrow or liver Disorders of porphyrin metabolism = porphyrias Inherited Acquired - lead, alcohol and other toxins, iron deficiency, renal or liver malfunctions.

Porphyrias Classification Based on Specific enzyme deficiency Hepatic vs erythropoietic Cutaneous vs neurologic Inherited or acquired

Porphyrias Clinical symptoms Port wine colored urine Cutaneous photosensitivity Itchy skin (photodermitidis) Hyperpigmentation Inflammatory reaction occurs on exposure to ultraviolet light Neurologic abnormalities

Myoglobin Elevations Acute myocardial infarction Renal failure Vigorous exercise Electric shock Intramuscular injections

LEAD Clinical Features Children CNS symptoms: headache,clumsiness, seizures, behavioral changes GI symptoms: Abdominal pain, colic, constipation Adults Peripheral neuropathies, motor weakness, anemia

References Arneson, W. (2007). Clinical Chemistry: A Laboratory Perspective. Philadelphia, PA: F.A. Davis Company. Bishop, M., Fody, E., & Schoeff, l. (2010). Clinical Chemistry: Techniques, principles, Correlations. Baltimore: Wolters Kluwer Lippincott Williams & Wilkins. Sunheimer, R., & Graves, L. (2010). Clinical Laboratory Chemistry. Upper Saddle River: Pearson. Wier, Dr. Edward. (2010, December). Principles and Pathology of Iron Metabolism [PowerPoint slides].