What forms of systemic vasculitis occur in childhood?
The most common small-vessel vasculitis in childhood is HSP . Small-vessel vasculitis can also be a component of many of the juvenile systemic CTDs including systemic JIA, JDM, and SLE. ANCA-associated small-vessel vasculitis (GPA, MPA, Churg–Strauss) may present initially mimicking HSP. Primary central nervous system (CNS) vasculitis may involve small- or medium-sized vessels of the brain and spinal cord. About 5% cases of polyarteritis nodosa (PAN) , which is a medium-vessel vasculitis, occurs in childhood and, as in adults, is characterized by rash, fever, weight loss, myositis, and cutaneous nodules. Life-threatening renal, gastrointestinal (GI), cardiac, and CNS involvement is often seen. Cutaneous PAN has also been reported. Kawasaki disease is a uniquely pediatric vasculitis
Large-vessel vasculitis is unusual in childhood; however, up to 30% of all Takayasu arteritis cases occur in childhood, typically developing in adolescent females.