MLAB 2401: Clinical Chemistry Keri Brophy-Martinez Chapter 5: Hemoglobin Production Disorders

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

Hemosiderosis Excessive levels of iron in storage

Hemochromatosis Characterized by an increased rate of absorption and less ferritin production Excessive iron deposits in organs 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 Iron Overdose Hematochromatosis Slight Decrease Malnutrition Variable Chronic anemia Normal/decreased Normal/increased decreased Acute liver disease

Case Scenario #1 A 40-year-old female is scheduled to have an elective surgery. Her physician ordered a routine CBC pre-op. The following test results were obtained: Test Result Reference Range Hgb (g/dL) 10 12-16.0 Hct (%) 29.9 42-52 MCV (fL) 75 80-100 MCHC (g/dL) 30 32-36 WBC (x 103/L) 6.0 4.5-11 Plts (x 109/L) 200 150-450

Case Scenario #1 On review of her blood smear, the technician noted target cells. What other types of morphology would we expect to see on this patient? The physician then ordered a serum iron, ferritin and TIBC level.

Case Scenario #1 Below are the results on the additional tests: What is her diagnosis? Test Result Reference Range Serum iron ( µg/dL) 20 65-165 Ferritin ( µg/dL) 5 20-200 TIBC ( µg/dL) 550 260-440

Hemoglobin Disorders Refer to Hematology notes Chapter 10: Hemoglobinopathies Chapter 11: Thalassemia

Porphyrin Disorders= Porphyrias Inherited or Acquired Enzyme deficiencies resulting in overproduction of heme precursors in bone marrow or liver

Porphrias Classification Based on Specific enzyme deficiency Hepatic vs erythropoietic Cutaneous vs neurologic

Porphyrias Clinical symptoms Cutaneous photosensitivity Itchy skin Hyperpigmentation Inflammatory reaction occurs on exposure to ultraviolet light Neurologic abnormalities due to increased ALA and PBG

Porphyrin Conditions Secondary Conditions Porphyrinuria Increase in coproporphyrin production Causes Lead intoxication Liver damage Infection Accelerated erythropoiesis Porphyrinemia Increase in erythrocytic protoporphyrin concentration Iron deficiency Impaired Iron absorption Chronic infection

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

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

Case Scenario #2 A mother brings her active 2-year-old son to the pediatrician for a routine visit. The physician orders a CBC. Below are the results: Test Result Reference Range Hgb (g/dL) 10.2 14-17.4 Hct (%) 30.6 36-46

Case Scenario #2 The mother reports that her son has had some constipation and abdominal pain. The child does eat well, and the mother gives the child a vitamin supplement, which includes iron The mother did mention that they live in an older home that is in need of repainting. The physician orders further testing…

Case Scenario #2 Results of testing Test Result Reference Range Serum iron 120 65-165 Ferritin 150 20-200 Whole blood lead (µg/dL) 60 < 10 Erythrocyte protoporphyrin (µg/dL) 17-77

What is the diagnosis? Lead Poisoning How does this occur? Lead inhibits certain enzymes in the heme synthesis pathway

Case Scenario #2 IDA was ruled out based on the serum iron and ferritin levels