title: Classic polyarteritis nodosa associated with hepatitis C virus infection: a case report.
abstract: BACKGROUND
  Hepatitis C virus has been under-recognized as an etiologic factor for polyarteritis nodosa and the presence of hepatitis C antigenemia in patients with polyarteritis nodosa has been reported as insignificant. In the literature hepatitis C virus-associated polyarteritis nodosa is a rare and controversial entity.
  
  
  METHODS
  A 34-year-old Sri Lankan Tamil man presented to our facility with a two-week history of slow-resolving pneumonia of the right mid and lower zones. On physical examination he had panniculitic type tender skin nodules with background livedo reticularis. A skin biopsy was suggestive of a small and medium vessel vasculitis compatible with polyarteritis nodosa. He was tested positive for hepatitis C antibodies. A serum cryoglobulin test was negative but perinuclear antineutrophilic cytoplasmic antibody test was positive. Serum complement levels were reduced. He was diagnosed as having classic polyarteritis nodosa associated with hepatitis C infection. He later developed left-sided radiculopathy involving both upper and lower limbs and an ischemic cardiac event. His hepatitis C infection was managed with polyethylene glycol-interferon 2α combined with oral ribavirin. Simultaneously, his classic polyarteritis nodosa was treated with prednisolone and cyclophosphamide. He made a good recovery.
  
  
  CONCLUSIONS
  Hepatitis C virus infection is capable of inducing a fulminant form of vasculitis in the form of polyarteritis nodosa. It may be easily confused early in its course with mixed cryoglobulinemia, which is commonly known to be associated with hepatitis C virus. Awareness of hepatitis C virus-related polyarteritis nodosa helps in diagnosing the condition early so combined immunosuppressive and antiviral treatment can be started as soon as possible.
authors.affiliation: University Medical Unit, Colombo North Teaching Hospital, Ragama, Sri Lanka. damith_rodrigo@yahoo.com.
authors.forename: Damith
authors.initials: D
authors.lastname: Rodrigo
authors.forename: Ruwan
authors.initials: R
authors.lastname: Perera
authors.forename: Janaka
authors.initials: J
authors.lastname: de Silva