Case Report: Localized hyperinflammatory response in the bulla after mosquito bites in a patient with systemic lupus erythematosus.

A patient with systemic lupus erythematosus developed localized swelling with blistering after mosquito bites. A complete blood count showed eosinophils were 1.09 × 109/L (13.9%). Total IgE was more than 5,000 KU/L. Examination of the blister fluid showed very high levels of interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17, tumor necrosis factor (TNF)-α, interferon (IFN)-α, and IFN-γ cytokines, while these serum cytokine levels were normal. After sterile extraction of the blister fluid, the inflammatory substances were removed, and the blister gradually disappeared. This might be a special manifestation after mosquito bites in a patient with a background of autoimmune diseases. Particular attention should be paid to patients with autoimmune diseases after insect bites.