Genetic Testing for HHT Should Not Be Approved for This Patient
This patient does not meet clinical criteria for HHT genetic testing and should be denied coverage based on current evidence-based guidelines. The patient fails to satisfy the Curaçao diagnostic criteria, which require at least 2 of 4 clinical features for a "possible" diagnosis that would warrant genetic testing 1, 2.
Clinical Assessment Against Curaçao Criteria
This 45-year-old woman meets only one criterion out of four required 3, 1:
- Epistaxis: Absent - Patient explicitly denies recurrent nosebleeds 1
- Telangiectases: Absent - No documented cutaneous or mucosal telangiectases 3
- Visceral lesions: Absent - Normal brain MRI, no AVMs identified on multiple imaging studies including abdominal CT/ultrasound and echocardiogram 1
- Family history: Does NOT meet criteria - Mother's records show she did not meet Curaçao criteria for HHT diagnosis 1, 2
The diagnosis is "unlikely" with fewer than two criteria present, making genetic testing inappropriate at this time 1, 2.
Critical Analysis of the Family History
The family history does not support testing 1:
- The mother had a brain AVM rupture but did not meet Curaçao criteria for HHT diagnosis 2
- Isolated brain AVMs occur in the general population without HHT 4
- The children's nosebleeds and "possible" telangiectasias are unconfirmed and do not establish the mother's diagnosis retrospectively 1, 2
A first-degree relative must have a definite HHT diagnosis (3 Curaçao criteria) to satisfy the family history criterion 3, 1, 2.
Age-Related Penetrance Argument Against Testing
The genetic counselor's note that "90% of people with HHT will have symptoms by their 40's" actually argues against this patient having HHT 1:
- At age 45, she should have manifested epistaxis (present in >90% of adults with HHT) if she carried a pathogenic mutation 5, 4
- The absence of any characteristic symptoms at this age makes HHT highly unlikely 4
Appropriate Indications for HHT Genetic Testing
Guidelines specify clear indications where this patient does not qualify 1:
Hayes Rating B (appropriate for testing):
- Symptomatic individuals meeting definite Curaçao criteria (3+ features) for family member testing 1
- Symptomatic individuals NOT meeting definite criteria when used to confirm diagnosis - this patient is asymptomatic 1
- Asymptomatic family members when a relative has confirmed HHT - the mother did not have confirmed HHT 1, 4
This patient falls into none of these categories 1.
Recommended Clinical Pathway
The appropriate next steps are 1:
Defer genetic testing until/unless the patient develops at least one additional Curaçao criterion 1, 2
Evaluate the children directly - If they truly have recurrent epistaxis and telangiectases, they should be assessed independently using Curaçao criteria 1, 2
Clinical surveillance only - Given the family history of brain AVM (even without confirmed HHT), consider brain MRI screening, which has already been performed and was normal 1
Reassess if symptoms develop - If the patient develops spontaneous recurrent epistaxis or visible telangiectases, genetic testing would become appropriate 1, 2
Common Pitfall to Avoid
Do not conflate "family history of AVMs" with "family history of HHT" 2. Isolated AVMs occur in non-HHT populations, and the Curaçao criteria specifically require a first-degree relative with a definite HHT diagnosis (3 criteria), not just vascular malformations 3, 1, 2. The mother's failure to meet Curaçao criteria is explicitly documented and disqualifies this as a valid family history criterion 1.
Coverage Decision
Deny genetic testing - The patient does not meet MCG criteria (requires 2+ Curaçao features), does not fit Hayes Rating B categories for appropriate testing, and lacks sufficient clinical suspicion to justify the expense and potential for uninformative results 1.