D2I2.
autoimmune

Polyarteritis nodosa

Polyarteritis nodosa (PAN) is a necrotizing of blood (vasculitis) affecting medium-sized muscular , typically involving the arteries of the kidneys and other internal organs but generally sparing the lungs' circulation. Small aneurysms are strung like the beads of a rosary, therefore making this "rosary sign" an important diagnostic feature of the vasculitis. PAN is sometimes associated with by the B or hepatitis C virus. The condition may be present in infants.

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Plain-language summary adapted from Wikipedia. Not medical advice.