Hereditary Hemochromatosis
Continuing Education Credits
Hereditary hemochromatosis is a disorder of iron regulation that can over time lead to widespread organ damage, a variety of chronic disorders, and even death. Early detection may permit treatment before the development of substantial iron overload. The laboratory technologist plays a major role in detecting and controlling this disease. In this course, you will learn about the basics of iron metabolism, the signs and symptoms of hemochromatosis, how it is treated, and the laboratory tests and procedures that are vital to its diagnosis and maintenance.
Objectives
- Describe basic aspects of normal iron metabolism.
- Explain the pathophysiology of iron overload associated with hereditary hemochromatosis (HH).
- Discuss mutations associated with HH, including prevalence in various ethnic groups and penetrance.
- List early and late clinical signs and symptoms of HH.
- Evaluate screening and confirmatory laboratory tests used in detection and diagnosis of iron overload and HH.
- Describe initial and long-term treatment and management options for HH.
Course Outline
- Introduction
- Introduction
- HH is the most common cause of which of the following conditions?
- Normal Iron Metabolism
- Overview of Iron Metabolism
- Storage Iron
- Iron Intake and Recycling
- Regulation of Iron Equilibrium
- Regulation of Iron Equilibrium, continued
- Iron Transport
- Which compound normally contains the majority of the body's total iron?
- What is a mobilizable, water-soluble form of storage iron bound to protein?
- What percentage of dietary iron is normally absorbed daily?
- True or False: Decreased hepcidin levels are related to increased iron absorption into the bloodstream.
- What is the protein that carries iron in the blood plasma?
- Pathophysiology of Iron Overload in HH
- Altered Iron Absorption
- Development of Iron Overload
- What is the fundamental defect involving iron metabolism in HH?
- Mutations Associated with HH
- HFE and Other Genes
- Specific HFE Mutations
- Specific HFE Mutations, continued
- Epidemiology of HFE Mutations
- Incomplete Penetrance
- Prevalence of HFE Mutations
- Mutations in which gene account for the majority of cases of HH?
- True or False: In C282Y mutation, the HFE protein's function is altered due to binding with beta-2 microglobulin decreasing and HFE remaining within the cell's Golgi apparatus.
- Which genotype accounts for the most significant percentage of cases of HH?
- Diagnosis
- General Clinical Considerations
- Signs and Symptoms of HH
- Diagnosing HH
- Example of a Testing Algorithm for HH
- Which of the following characterizes the early signs and symptoms of HH?
- Which of the following are needed for a diagnosis of HH?
- Laboratory Testing for HH
- General Overview of Laboratory Testing
- Serum Iron (SI)
- Transferrin (Tf) and Total Iron Binding Capacity (TIBC)
- Transferrin Saturation (TS)
- Transferrin Saturation (TS), continued
- Serum Ferritin (SF)
- Unsaturated Iron Binding Capacity (UIBC)
- Molecular Tests for Genetic Mutations
- Definitive Tests for Iron Overload
- Quantitative Phlebotomy
- Screening for Hereditary Hemochromatosis
- What laboratory test reflects circulating iron that is bound to transferrin?
- What would you expect the serum iron (SI) and total iron binding capacity (TIBC) to be in a person with HH?
- Which laboratory assay is considered to be a confirmatory test for HH?
- Why is serum ferritin (SF) a less than optimal screening test for HH?
- What unsaturated iron binding capacity (UIBC) result is consistent with a diagnosis of HH?
- Which statement best describes the use of the liver biopsy in suspected cases of HH?
- Treatment and Management of HH
- Rationale for Treatment
- Initial Treatment
- Initial Treatment, continued
- Maintenance Therapy
- Other Treatments
- Prognosis and Mortality
- What is a typical schedule for phlebotomy during the initial treatment phase for HH?
- What drug may be used to decrease iron levels in patients with iron overload?
- How long should therapy continue for patients with HH?
- What is the major determinant of prognosis for patients with HH?
- Case Study
- Case StudyAndrew is a 49-year-old Caucasian male seen by a primary care doctor. He reports that for the last 1-2 years or longer, he has experienced moderate fatigue, aches and pains in multiple joints, impotence, and mild depression. He has a family history, including diabetes in both parents and an older brother who died of liver disease at age 60. Andrew is unsure of his brother’s complet
- Case Study continuedAndrew is a 49-year-old Caucasian male seen by a primary care doctor. He reports that for the last 1–2 years or longer, he has experienced moderate fatigue, aches and pains in multiple joints, impotence, and mild depression. He has a family history, including diabetes in both parents and an older brother who died of liver disease at age 60. Andrew is unsure of his brother
- Case Study, continuedAndrew is a 49-year-old Caucasian male seen by a primary care doctor. He reports that for the last 1–2 years or longer, he has experienced moderate fatigue, aches and pains in multiple joints, impotence, and mild depression. He has a family history, including diabetes in both parents and an older brother who died of liver disease at age 60. Andrew is unsure of his broth
- References
- References
Additional Information
Level of instruction: Intermediate
Intended Audience: Medical laboratory scientists, medical laboratory technicians, pathology residents, MLS students, and other health care personnel who have an interest in this subject matter.
Author Information: Rebecca J. Laudicina, Ph.D., MLS(ASCP)CM is Professor Emeritus in the Division of Clinical Laboratory Science at The University of North Carolina at Chapel Hill’s School of Medicine. She obtained a Master of Education and Ph.D. in Educational Psychology from Temple University. She is the author of numerous publications including many in the field of hematology.
Reviewer Credentials:
Joshua J. Cannon, MS, MLS(ASCP)CMSHCM received
his Bachelor of Science and Master of Science in Medical Laboratory Science
from Thomas Jefferson University in Philadelphia, PA. He holds Medical
Laboratory Scientist and Specialist in Hematology certifications through the
ASCP Board of Certification. He was a professor at Thomas Jefferson University for
seven years before transitioning into his current role as Education Developer
at MediaLab. His areas of expertise and professional passions include clinical
hematology and interprofessional education.
Laurie Bjerklie, MA, MLS(ASCP)CM is currently an Education Developer for MediaLab and LabCE. She earned a B.S. in Medical Laboratory Science from the University of North Dakota and an M.A. in Curriculum and Instruction from Saint Xavier University. She has over 15 years of experience in higher education and has held program director and faculty positions in both MLT and MLS programs.
Course Description: This course offers an in-depth look at the condition of hemochromatosis. It begins with a discussion about normal iron metabolism and continues by explaining the pathophysiology of iron overload that occurs in the condition of hemochromatosis. Clinical considerations and laboratory testing are also discussed.