From the Guidelines
The diagnostic blood test for Hereditary Hemochromatosis (HH) should include the assessment of serum iron parameters, specifically transferrin saturation and serum ferritin, as the first step in testing. This approach is based on the latest guidelines from the Journal of Hepatology 1, which provide a strong recommendation (LoE 3, strong consensus) for the use of these parameters in the initial assessment of haemochromatosis.
Key Diagnostic Parameters
- Transferrin saturation: This parameter is crucial in the diagnosis of haemochromatosis, although it shows significant variability, which limits its usefulness 1.
- Serum ferritin: Elevated levels of ferritin are indicative of iron overload and are a key marker in the diagnosis of haemochromatosis. However, ferritin is also an acute phase reactant and can be elevated in other conditions, such as fatty liver disease or metabolic syndrome, which must be considered during the diagnostic process 1.
Diagnostic Approach
The diagnostic approach should involve:
- Initial screening with transferrin saturation and serum ferritin levels.
- If these tests are abnormal, further evaluation, including genetic testing for HFE gene mutations (particularly C282Y and H63D), should be considered to confirm the diagnosis.
- It is essential to note that genetic testing should be accompanied by appropriate genetic counseling, discussing the risks, benefits, and limitations of such testing, as recommended by the American College of Physicians 1.
Importance of Early Detection
Early detection of hereditary hemochromatosis is critical because it allows for timely intervention with therapeutic phlebotomy, which can prevent organ damage and improve quality of life. Regular monitoring with ferritin tests is necessary to ensure that iron levels remain within the target range, thereby preventing the complications associated with iron overload, such as liver disease, diabetes, heart problems, and joint pain.
From the Research
Diagnostic Blood Test for Hereditary Hemochromatosis (HH)
The diagnostic blood test for Hereditary Hemochromatosis (HH) involves the measurement of certain parameters to detect iron overload. These parameters include:
- Serum transferrin saturation
- Serum ferritin level
- Serum iron concentration
- Total iron binding capacity (TIBC)
- Percent saturation of transferrin
Initial Screening Test
The initial screening test for HH is the evaluation of possible iron overload via measurement of serum transferrin saturation and ferritin level 2, 3, 4, 5. This test is used to identify individuals who may be at risk of developing iron overload and to detect those who already have significant iron loading.
Genetic Testing
Genetic testing, such as HFE genotyping, can be used in combination with serum biochemical measurements to define the presence of likely iron overload and the underlying genetic disorder 2, 4, 6. This test is particularly useful for families with an affected individual, as it can help identify other family members who may be at risk of developing HH.
Diagnostic Criteria
The diagnosis of HH requires confirmation of increased serum ferritin levels and transferrin saturation, with or without symptoms 5. Subtyping is based on genotypic expression, and serum ferritin measurement is the most useful prognostic indicator of disease severity.
Screening Recommendations
Screening for HH is recommended in high-risk groups, such as first-degree relatives of patients with classical HFE-related hemochromatosis, those with evidence of active liver disease, and patients with abnormal iron study results 2, 3, 4, 5. However, universal screening for HH is not recommended.