Based on this study, an involvement of IL-31 in the pathogenesis of the Th-2 mediated immune response in SRMA and also in MUO can be assumed; in particular, the systemic changes in SRMA like generalized arteritis and the proinflammatory status (pyrexia, leukocytosis) can be well explained in SRMA. The gene discussed is IL31; the disease is Fever.