polyarteritis nodosa (MONDO_0019170) (PAN) is a rare, clinically heterogeneous, rheumatologic disease characterized by necrotizing inflammatory lesions affecting small- and medium-sized blood vessels. PAN most commonly affects skin, joints, peripheral nerves, the gut, and the kidney. Also known as: Küssmaul-Maier disease, PAN, classic polyarteritis nodosa, classical polyarteritis nodosa, panarteritis nodosa, periarteritis nodosa.