Abstract
We report the case of a 4-year-old boy with IgA vasculitis who developed a recurrence of IgA
vasculitis 6 months after its first episode. He had a high fever, severe abdominal symptoms, arthralgia, and a
marked increase in serum C-reactive protein（CRP） level （up to 22.18mg/dL）. Thus, differentiation from
sepsis was needed. Abdominal sonography revealed thickening of the small intestinal wall, enlarged
mesenteric lymph nodes, and elevated echogenicity of mesenteric adipose tissue in the lower right abdomen.
He was diagnosed as having mesenteric lymphadenitis and panniculitis caused by recurrence of IgA
vasculitis, which required prednisolone administration. As sepsis could not be ruled out, an antibacterial drug
was administered after blood culture. Palpable purpura was observed in his lower extremities after the
clinical features promptly improved.
We speculate that the patient’s high fever and elevated serum CRP level resulted from the formation
of mesenteric lesions after the breakdown of the gut barrier by IgA vasculitis.
