MLAB 2401: Clinical Chemistry
Keri Brophy-Martinez
Disorders of Iron, Porphyrins and Hemoglobin
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
Hemochromatosis
Hemosiderosis
 Hereditary disorders of
 Secondary/acquired iron
iron metabolism
 Hemosiderin is deposited
within cells and interstitial
fluid
 Primarily effects liver,
heart, endocrine glands
 Irreversible
accumulation
 Hemosiderin is deposited
in cells only
 No tissue damage
 Reversible
Hemochromatosis
 Characterized by an increased
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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
Condition
Serum Iron Transferrin
Ferritin
% Saturation
IDA
Decreased
Increased
Decreased
Decreased
Iron Overdose
Increased
Decreased
Increased
Increased
Hematochromatosis
Increased
Slight Decrease
Increased
Increased
Malnutrition
Decreased
Decreased
Decreased
Variable
Chronic anemia
Decreased
Normal/decreased
Normal/increased
decreased
Acute liver disease
Increased
Variable
Increased
Increased
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.
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Philadelphia, PA: F.A. Davis Company.
Bishop, M., Fody, E., & Schoeff, l. (2010). Clinical Chemistry:
Techniques, principles, Correlations. Baltimore: Wolters Kluwer
Lippincott Williams & Wilkins.
http://phosphorus15.glogster.com/
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].