K E Y W O R D S : allergy, case report, diabetes, insulin, metacresol Since the introduction of human insulin, the incidence of allergic reactions has decreased from 50% to 1%-2.4%. 1 The culprit may be insulin or an excipient.
| CASE REPORTA 79-year-old woman presented with erythematous papules on the abdomen following the injections of biosynthetic insulin (Humuline; Eli Lilly, Brussels), spontaneously resolving after 3 days. Her treatment consisted of regular insulin with long-acting protamine-coupled insulin (Humuline 30/70). She reported previous urticaria and angioedema with sea food and amoxicillin + clavulanic acid.Allergy test results are summarized in Table 1. Skin biopsies of an abdominal lesion and a positive prick test to 10 −3 diluted metacresol showed superficial and deep perivascular infiltration of lymphocytes, neutrophils, and eosinophils. Skin contact allergy associated with immediate reaction to metacresol was diagnosed. The allergic symptoms did not recur using a metacresol-free insulin (Implantable Insuman; Sanofi) used in insulin pumps or in intraperitoneal insulin release devices (Figure 1).
316COLSON ET AL.