Differential Diagnosis for Sudden Onset of Polyarteritis in Setting of Familial Hypercholesterolemia with Recent Discontinuation of Nexletol
Single Most Likely Diagnosis
- Rebound Effect of Bempedoic Acid (Nexletol) Discontinuation: The recent discontinuation of Nexletol, which works by inhibiting ATP citrate lyase to reduce cholesterol synthesis, could lead to a rebound effect. This effect might cause a sudden increase in cholesterol levels, potentially exacerbating or triggering polyarteritis in a patient with familial hypercholesterolemia. The mechanism involves a sudden surge in cholesterol production upon stopping the medication, which could lead to increased inflammation and vascular damage.
Other Likely Diagnoses
- Familial Hypercholesterolemia-Related Vasculitis: Given the patient's history of familial hypercholesterolemia, there's a possibility that the polyarteritis is directly related to the disease process itself, with high levels of LDL cholesterol contributing to vascular inflammation and damage.
- Cholesterol Emboli Syndrome: Although less common, the sudden onset of polyarteritis could be related to cholesterol emboli syndrome, where fragments of atherosclerotic plaques break off and lodge in smaller arteries, causing inflammation and damage.
Do Not Miss Diagnoses
- Giant Cell Arteritis: This condition, although not directly related to familial hypercholesterolemia or Nexletol, is a form of large vessel vasculitis that can present with sudden onset of symptoms, including polyarteritis. Missing this diagnosis could lead to serious complications, including blindness and aortic aneurysm.
- ANCA-Associated Vasculitis: This group of diseases, including granulomatosis with polyangiitis, microscopic polyangiitis, and eosinophilic granulomatosis with polyangiitis, can present with a wide range of symptoms, including polyarteritis. They are critical to diagnose due to their potential for severe organ damage and the availability of effective treatments.
Rare Diagnoses
- Kawasaki Disease: Although extremely rare in adults, Kawasaki disease is a form of vasculitis that can present with sudden onset of symptoms, including polyarteritis. It's more commonly seen in children but should be considered in the differential diagnosis due to its potential for serious cardiac complications.
- Polyarteritis Nodosa (PAN) Triggered by Medication Withdrawal: While PAN is a rare condition, the recent discontinuation of Nexletol could theoretically trigger an immune response leading to PAN in a susceptible individual, especially in the context of an underlying condition like familial hypercholesterolemia.