Microscopic polyangiitis (MPA) is an autoimmune systemic vasculitis of small vessels. The condition has been best characterized in older adults and little is known of the natural history of this disease in children and adolescents. In this report, a case of an adolescent presenting with symptomatic anemia and syncopal episodes is described. An extensive evaluation ultimately led to the diagnosis of MPA. The unique findings in this case and review of the literature are presented, outlining the variable clinical presentations and challenge of diagnosing this condition in pediatric patients.