LabCE Course - Hereditary Hemochromatosis
Increased
Decreased levels of hepcidin are related to __________ iron absorption into the bloodstream
Middle-aged adults
In which age group is HH most likely to be initially detected based on clinical symptoms
Remove 2-6 blood units yearly
typical regimen for long-term maintenance therapy of individuals with HH
Inherited iron overload
HH is the most common cause of which of the following conditions
Its binding with beta-2 microglobulin is decreased and it remains within the cell's Golgi apparatus
How is the function of HFE protein altered in the C282Y mutation
Therapy should continue throughout the lifetime
How long should therapy continue for patients with HH
HFE
Mutations in which gene account for the majority of cases of HH
He had a brother who died of liver disease and parents with diabetes
What about this patient's medical and family histories suggests that he might have HH
Deferoxamine
What drug may be used to decrease iron levels in patients with iron overload
Joint pain
What is a common early symptom of HH
Ferritin
What is a mobilizable, water-soluble form of storage iron that is bound to protein
The serum ferritin decreases to between 20 and 50 ng/mL
What is a typical finding for determining the endpoint for the initial or iron-depletion phase of treatment for HH
Removing one unit (450 mL) of whole blood once or twice weekly
What is a typical schedule for phlebotomy during the initial treatment phase for HH
Testing family members of persons with HH
What is an appropriate use for molecular (DNA) tests for mutations of the HFE gene, the gene found in the majority of patients diagnosed with HH
Excessive dietary iron is absorbed
What is the fundamental defect involving iron metabolism in HH
Degree of organ damage from iron overload
What is the major determinant of prognosis for patients with HH
Absorption of excessive amounts of iron in the small intestine
What is the pathophysiology (direct cause) of the iron overload in HH
Transferrin
What is the protein that carries iron in the blood plasma
Serum iron
What laboratory test reflects circulating iron that is bound to transferrin
5-15%
What percentage of dietary iron is normally absorbed daily
Low
What unsaturated iron binding capacity (UIBC) result is consistent with a diagnosis of HH
Increased SI and normal to decreased TIBC
What would you expect the serum iron (SI) and total iron binding capacity (TIBC) to be in a person with HH
Homozygous for C282Y
Which HFE genotype is most common in patients with HH
Hemoglobin
Which compound normally contains the majority of the body's total iron
C282Y/C282Y
Which genotype accounts for the greatest percentage of cases of HH
Molecular (DNA) assays for HFE mutations
Which laboratory assay is considered to be a confirmatory test for HH
Iron overload as identified through laboratory analyses for iron Presence of HFE mutations or other genetic mutations associated with iron metabolism Clinical signs and symptoms consistent with HH
Which of the following are needed for a diagnosis of HH
Vague, nonspecific, and variable
Which of the following characterizes the early signs and symptoms of HH
Elevated hemoglobin and hematocrit
Which of the following is NOT an expected or common laboratory finding in patients with HH
Only a small percentage of dietary iron is absorbed and used
Which statement best describes the relationship between dietary iron and iron absorption in a healthy individual
It can detect both liver fibrosis and assess the amount of iron in the liver
Which statement best describes the use of the liver biopsy in suspected cases of HH
It lacks specificity because ferritin is increased in inflammation
Why is serum ferritin (SF) a less than optimal screening test for HH
It is frequently elevated in a variety of clinical conditions
Why might serum ferritin (SF) alone be considered a less than optimal screening test for HH
Hemosiderin Ferritin
iron storage compounds
Regular blood donation
protective effect delaying symptoms in a person with HH