Polyarteritis nodosa: an evolving primary systemic vasculitis.

Area of Science:

• Rheumatology
• Immunology
• Genetics

Background:

• Polyarteritis nodosa (PAN) is a primary vasculitis of medium-sized arteries.
• Key discoveries include separating microscopic polyangiitis, identifying hepatitis B association, and recognizing DADA2.
• Changing nomenclature and identifying secondary causes have decreased reported PAN incidence.

Purpose of the Study:

• To review the evolving understanding and management of Polyarteritis Nodosa.
• To highlight the importance of differentiating primary PAN from secondary causes, particularly DADA2.
• To discuss current treatment strategies and their impact on prognosis.

Main Methods:

• Literature review of key historical and recent findings in PAN.
• Analysis of diagnostic criteria and evolving disease classification.
• Summary of clinical manifestations and treatment outcomes.

Main Results:

• PAN incidence has declined due to reclassification and identification of secondary causes.
• Common PAN manifestations include constitutional, skin, neurological, gastrointestinal, and renal symptoms.
• Adenosine deaminase 2 deficiency (DADA2) is a critical genetic mimic requiring specific treatment (e.g., TNF inhibitors).

Conclusions:

• Effective management of PAN relies on accurate diagnosis, distinguishing primary from secondary forms.
• Early identification of DADA2 is vital for preventing severe outcomes with targeted therapies.
• Modern immunosuppressive therapy has transformed PAN prognosis, with survival rates exceeding 80%.