A case of insulin allergy: the crystalline human insulin may mask its antigenicity

A case of insulin allergy successfully managed using multihexamer-forming insulin degludec combined with liraglutide

BACKGROUND

Insulin allergy, one of insulin's adverse effects, is rare, especially in patients with Type 2 diabetes, but management is difficult and no effective strategy has yet been established. We experienced an insulin allergy case successfully managed with a novel combination of insulins.

CASE REPORT

A 38-year-old woman started insulin therapy when diabetes was diagnosed at age 19 years. Despite poorly controlled diabetes because of poor adherence, she hoped to conceive a child and continuous subcutaneous insulin infusion was introduced using insulin aspart at age 32 years. One month thereafter, she developed skin reactions at the subcutaneous insulin infusion catheter insertion site. The patient was then tested for all rapid-acting insulin formulations, all of which triggered local reactions. She decided to continue the continuous subcutaneous infusion of human regular insulin, accompanied by oral cetirizine hydrochloride and betamethasone valerate ointment. The patient was admitted to our hospital at age 38 years with high HbA_1c levels. She was tested for all long-acting insulin analogues. All results, except for insulin degludec, were positive. She discontinued continuous subcutaneous insulin infusion and switched to insulin degludec combined with liraglutide. The allergic reactions had completely disappeared and her blood glucose was well controlled by the time of discharge.

CONCLUSION

Our patient was allergic to all insulin formulations except insulin degludec. Her allergic reactions completely disappeared after switching to insulin degludec. The crystallized structure of this insulin might mask its skin allergen antigenicity. Furthermore, her postprandial hyperglycaemia was successfully controlled with liraglutide. We propose multihexamer-forming ultra-long-acting insulin plus glucagon-like peptide-1 analogues as a therapeutic option for patients with insulin allergy.

Successful management of insulin allergy and autoimmune polyendocrine syndrome type 4 with desensitization therapy and glucocorticoid treatment: a case report and review of the literature

Introduction. Insulin allergy is a rare complication of insulin therapy, especially in type 1 diabetes mellitus (T1DM). Key manifestations are hypersensitivity-related symptoms and poor metabolic control. T1DM, as well as insulin allergy, may develop in the context of autoimmune polyendocrine syndrome (APS), further complicating management. Case Report. A 17-year-old male patient, diagnosed with T1DM, was treated with various insulin therapy schemes over several months, which resulted in recurrent anaphylactoid reactions and poor glycemic control, after which he was referred to our Endocrinology and Immunology Department. A prick test was carried out for all commercially available insulin presentations and another insulin scheme was designed but proved unsuccessful. A desensitization protocol was started with Glargine alongside administration of Prednisone, which successfully induced tolerance. Observation of skin lesions typical of vitiligo prompted laboratory workup for other autoimmune disorders, which returned positive for autoimmune gastritis/pernicious anemia. These findings are compatible with APS type 4. Discussion. To our knowledge, this is the first documented case of insulin allergy in type 4 APS, as well as this particular combination in APS. Etiopathogenic components shared by insulin allergy and APS beg for further research in immunogenetics to further comprehend pathophysiologic aspects of these diseases.

Solitary pancreas transplantation for life-threatening allergy to human insulin*

We report on a 30-year-old man, with type 1 diabetes mellitus, who developed generalized allergy to insulin consisting of several bouts of tremor, tachycardia, breathlessness and syncope. Strong positive reactions to protamine and metacresol were demonstrated by skin-prick testing. Symptoms persisted despite the use of antihistamine therapy, Actrapid HM Paraben and Monotard (insulin without protamine and metacresol) and immunosuppression (tacrolimus). He underwent a cadaver pancreas transplantation with portal-enteric drainage in June 2003. Following the antithymocyte globulin induction, immunosuppression consisted in tacrolimus and sirolimus without steroids. The patient subsequently reported a complete resolution of his symptoms and excellent glycaemic control. Thirteen months after transplantation, the patient developed oral ulcerations and severe leucopoenia initially attributed to sirolimus, which was subsequently stopped. A hyperglycaemic episode following corticosteroid therapy for acute rejection therapy required the reintroduction of insulin. Allergic manifestations reappeared promptly. Currently, 2 years after transplantation, the patient is euglycaemic without insulin (glycated haemoglobin 5.8%) and he is free of allergic reactions.

Insulin Allergy and Extensive Lipoatrophy in Child with Type 1 Diabetes

Insulin allergy and lipoatrophy in type 1 diabetic patients have been previously reported but the mechanisms are not well documented. Here, we report a case emphasizing the role of abnormal local immune reaction associated with cytokine hyper production. The patient is a 7-year-old boy with a familial history of common variable immunodeficiency. Eight months after the diagnosis of type 1 diabetes, he developed signs of insulin allergy expressed as continuously extensive and profound lipoatrophy contrasting with a well-preserved metabolic control. Specific insulin allergy was confirmed by skin prick tests that showed lymphoid activated cells in the subcutaneous tissue at the site of insulin injection. All therapies reported in the literature (antihistaminic, local steroid, change to lispro insulin, immunosuppressive treatment, subcutaneous insulin pump, peritoneal insulin infusion) were not efficient. It is suggested that familial disorders of immune cell functions with abnormal and excessive cytokine production might explain these adverse effects triggered by insulin with severe allergic reactions and lipoatrophy.

A case of human insulin allergy induced by short-acting and intermediate-acting insulin but not by long-acting insulin

A 66-year-old woman suffering from pollinosis developed generalized urticaria after injection of intermediate-acting insulin for diabetes mellitus. She had human insulin-specific IgE, and in skin tests was positive for human recombinant insulin and negative for additives. Uniquely, she reacted to fast-acting and slow-acting insulin but not to long-acting insulin. We further confirmed that human insulin preparations could stimulate her peripheral basophils to release a significant amount of histamine. Genetically generated human insulin analogs, aspart and lispro, induced positive skin tests and histamine release from basophils. She was recommended to use a long-acting insulin preparation and was free from symptoms thereafter.

Insulin allergy; desensitization with crystalline zinc-insulin and steroid tapering

The insulin analogues, aspart and lispro, have been considered safe alternatives for patients with insulin allergy, because of their decreased immunogenicity. However, recent several reports showed that neither of them was completely free from allergic reactions. We also experienced a patient with insulin allergy not only to human regular insulin but also to both of the insulin analogues. Interestingly, the insulin analogues, which readily dissociate from polymer to monomer, induced the most severe allergic reaction among several types of human insulin reagents in the present case. Allergy to crystalline zinc-insulin, the three-dimensional structure of which results in delayed dissociation and absorption, was negative on intradermal tests. However, its large subcutaneous injection caused local allergic reaction. These results suggested that the allergic reaction might depend on the rapidity of insulin monomerization and absorption, and thus that the immunogenic residue of insulin is concealed when insulin is polymerized. Based on the intradermal tests, we speculated that the antigenic epitope might be B30-Thr in the present case. We also report here the modified method of insulin desensitization using crystalline zinc-insulin with prednisolone tapering. This might be a simple and useful treatment for insulin allergy.

Primary systemic allergy to human insulin: recurrence of generalized urticaria after successful desensitization

Primary systemic allergy to human insulin is rare. We report a case of recurrent immediate local reactions followed eventually by generalized urticaria to recombinant human insulin (Humulin) in an insulin-dependent diabetic. Skin test to Humulin R was positive, and the patient was successfully desensitized using a modified rapid desensitization protocol. Two weeks later, he had another episode of generalized urticaria after Humulin R injection. His treatment was resumed at a lower dose, and within a week he was able to tolerate his usual regimen of insulin. To our knowledge, this is the first report of a recurrence of systemic reaction after successful desensitization.