OBJECTIVES: I. Assess xylose absorption and blood levels of neopterin and von Willebrand factor antigen in children with active hypersensitivity vasculitis associated with connective tissue disease. II. Correlate the bioavailability and kinetic rate constant of absorption of oral methylprednisolone with that of xylose. III. Compare the bioavailability and kinetic rate constant of absorption of oral methylprednisolone during active and quiescent disease in the same child.

PROTOCOL OUTLINE: Following a 12-hour fast, patients receive oral xylose and 2 hours later, oral methylprednisolone. The following day, patients receive intravenous methylprednisolone. Pharmacokinetic studies are performed each day. Patients are re-treated when disease becomes inactive (6-12 months later).

Ages Eligible for Study:  4 Years   -   18 Years,  Genders Eligible for Study:  Both

Criteria

Inclusion Criteria:

• Juvenile dermatomyositis with evidence of active vasculitis
• Hemoglobin at least 9 g/dL

Exclusion Criteria:

• Severe renal involvement
• Critically ill or unstable
• Diseases other than dermatomyositis with vasculitis