Fatal Coronary Artery Vasculitis With Mixed Features

Area of Science:

• Pathology
• Cardiovascular Medicine
• Immunology

Background:

• Atherosclerotic cardiovascular disease (ASCVD) is a common cause of sudden death, but its varied presentation necessitates cautious diagnosis by medical examiners.
• Accurate diagnosis is crucial, especially when underlying conditions mimic ASCVD, impacting patient management and understanding of disease processes.

Observation:

• Autopsy revealed hepatosplenic vasculitis with noncaseating granulomas and coronary fibrosis, initially suggesting late-stage polyarteritis nodosa (PAN).
• However, the absence of characteristic renal involvement and the granulomatous nature of hepatic vasculitis pointed towards IgG4-related disease, indicating a mixed-features presentation.

Findings:

• Histologic examination of coronary artery lesions was key to diagnosing vasculitis with mixed features.
• The case presented a diagnostic challenge due to overlapping features of polyarteritis nodosa (PAN) and IgG4 disease, complicated by limited patient history.

Implications:

• This case underscores the importance of detailed histologic examination in diagnosing complex vasculitides, particularly in sudden death investigations.
• Differential diagnosis of vasculitis affecting coronary arteries requires careful consideration of overlapping features, especially in cases with atypical presentations like the one described.