Addressing Palliative Care Gaps for Rare Congenital Disease in Adults: CM-AVM2 as an Example.

Capillary malformation-arteriovenous malformation type 2 (CM-AVM2) is a rare vascular disorder marked by complex, progressive symptoms and limited treatment options. As more individuals with rare diseases reach adulthood, palliative care plays an essential role in supporting quality of life when disease-directed therapies begin to fail. We present a young adult male with EPHB4-positive CM-AVM2, transferred to our tertiary care center for progressive malnutrition, refractory diarrhea, and worsening abdominal pain despite extensive subspecialty care. His hospitalization was marked by escalating symptom burden, limited response to medical therapies, and increasing emotional distress for both patient and family. Palliative care was consulted to assist with pain control and symptom management, with initial reluctance for discussing goals of care (GOC). Through medication optimization, dynamic communication, and consistent interdisciplinary collaboration, the team helped stabilize aspects of his comfort and gradually facilitated GOC discussions. Our case emphasizes the value of integrating palliative care in rare disease management, particularly when longstanding treatments are refractory. We further discuss how palliative care in this setting differs from standard frameworks, requiring proactive use of disease-specific resources and protracted, anticipatory care planning to optimize quality of life.