Endocrine Abstracts

Introduction: Besides insulin allergy, several other forms of insulin intolerance are possible. Adipose panniculitis (AP) is an acute form.

Purpose: Describe the clinical, paraclinical and evolution of AP.

Clinical case: 64-year-old patient, type 2 diabetic for 24 years on premixed human insulin for 10 years. He consults for itchy erythematous lesions at the insulin injection sites. The lesion begins with an immediate pruritus then appearance a few hours later of a local inflammation which increases in diameter. The examination finds an induration of 10 cm in diameter of necrotic aspect with improvement under topical corticosteroids. Several types of human insulin and analogues have been used. We eliminated an allergy to protamine, metacresol and zinc. likewise, dermographism has been eliminated. The pharmacovigilance investigation incriminated INSULATARD, ACTRAPID, APIDRA and LANTUS. Skin biopsy showed fatty panniculitis. The management was to put the patient on Lantus and Apidra with dose splitting on different sites. The evolution was favorable.

Discussion: Manifestations of insulin intolerance can occur several weeks, months or sometimes years after the start of insulin therapy. The time to onset of symptoms was very suggestive of drug origin. The evolution when the injections were stopped was marked by a regression of the inflammatory signs. Re-administrations at other sites reproduced the same lesions. It is an inflammatory panniculitis compatible with type III delayed hypersensitivity. For our patient: favorable evolution under fractionated LANTUS + APIDRA with topical corticosteroid.

Conclusion: Insulin allergy requires prompt diagnosis and management to ensure safe glycemic control.