A case report and systematic literature review: insulin-induced type III hypersensitivity reaction

Insulin-induced type III hypersensitivity reactions (HSRs) are exceedingly rare and pose complex diagnostic and management challenges. We describe a case of a 43-year-old woman with type 1 diabetes mellitus (DM), severe insulin resistance, and subcutaneous nodules at injection sites, accompanied by elevated anti-insulin IgG autoantibodies. Treatment involved therapeutic plasma exchange (TPE) and intravenous immunoglobulin (IVIg) as bridge therapy, followed by long-term immunosuppression, which reduced autoantibody levels and improved insulin tolerance. Given the limited treatment guidelines, we conducted a comprehensive literature review, identifying 16 similar cases. Most patients were females with a median age of 36.5 years; 63% had type 1 DM, and 44% had concurrent insulin resistance (56% with elevated autoantibodies). Treatment approaches varied, with glucocorticoids used in 67% of cases. Patients with type 1 DM were less responsive to steroids than those with type 2 DM, and had a more severe course. Of those patients with severe disease necessitating immunosuppression, 66% had poor responses or experienced relapses. The underlying mechanism of insulin-induced type III HSRs remains poorly understood. Immunosuppressive therapy reduces anti-insulin IgG autoantibodies, leading to short-term clinical improvement and improved insulin resistance, emphasizing their crucial role in the condition. However, the long-term efficacy of immunosuppression remains uncertain and necessitates continuous evaluation and further research.

Autoimmune Hypoglycemia With Anti-Insulin Autoantibodies in an Eighty-One-Year-Old Woman Without Apparent Risk Factors

Background/Objective

Insulin autoimmune syndrome (IAS) is a very rare cause of hypoglycemia presenting with recurrent fasting or postprandial hypoglycemia episodes with elevated serum insulin levels and insulin autoantibodies. The objective of this case is to highlight the importance of considering IAS in patients with hypoglycemia.

Case Report

We present a case of an 81-year-old female who presented with symptoms of hypoglycemia. She was found to have hyperinsulinemic hypoglycemic episodes without any apparent risk factors for IAS. She had positive-insulin autoantibodies in her serum leading to the diagnosis of IAS. Acutely, hypoglycemia was managed with D50 pushes, oral glucose, and glucagon injection.

Discussion

Patients who present with hypoglycemia due to endogenous hyperinsulinemia should have IAS considered as a possible differential diagnosis. Insulin autoantibodies are measured as the gold standard diagnostic test for IAS. Foods with a low glycemic index are the primary treatment for IAS.

Conclusion

This case presentation highlights the importance of considering IAS as a differential diagnosis in patients presenting with hypoglycemia secondary to hyperinsulinemia, even in the absence of apparent risk factors.

Comparison of patient characteristics between East Asian and non-East Asian patients with insulin autoimmune syndrome

OBJECTIVE

Insulin autoimmune syndrome (IAS) is the third most common cause of spontaneous hypoglycaemia in Japan but very rare in the rest of the world. We aimed to identify factors, which are associated with the occurrence of IAS and which may differ between East Asian and non-East Asian patients.

DESIGN

A PubMed search using the search terms 'insulin autoimmune syndrome' and 'Hirata disease' revealed a total of 287 reports of IAS cases, including one previously unpublished own case.

RESULTS

Mean age (±standard deviation) was 52 ± 19 years in East Asian and 54 ± 21 years in non-East Asian patients (p > .05). In both groups, there were more females. Mean body mass index was lower in East Asian than in non-East Asian patients (23.0 ± 4.3 vs. 27.1 ± 5.6 kg/m² , p < .0001). Postprandial hypoglycaemia was more common in non-East Asian patients (p < .05). East Asian patients took more frequently antithyroid medications and non-East Asian patients angiotensin-converting enzyme (ACE) inhibitors (both p < .0001). Graves' disease and other autoimmune diseases were more frequently observed in East Asian patients (both p < .01). Parameters of glucose metabolism were comparable in both groups, independent of diabetes diagnosis (p > .05), except for insulin that was higher in East Asian compared to non-East Asian metabolically healthy patients (p < .01). Human leukocyte antigen (HLA)-DRB1*0406 was the most frequent HLA-type in East Asian patients (p < .0001), whereas DRB1*0403 and *0404 were more frequent in non-East Asian patients (both p < .05). Non-East Asian patients received more secondary treatments, including plasmapheresis and rituximab, whereas medication discontinuation was more common in East Asian patients (all p < .05). Outcome was similar in both groups (p > .05).

CONCLUSIONS

Factors associated with IAS markedly differ between East Asian and non-East Asian patients, with autoimmune disorders, particularly Graves' disease, antithyroid medications, and HLA-DRB1*0406 more prevalent in East Asian patients and cardiovascular and plasma cell diseases, ACE inhibitors and HLA-DRB1*0403 more prevalent in non-East Asian patients.

Islet Autoantibodies in the Patients with Sjogren's Syndrome and Thyroid Disease and Risk of Progression to Latent Autoimmune Diabetes in Adults: A Case Series

The glutamic acid decarboxylase 65 antibody (GAD65-Ab) is an autoimmune marker in some diseases such as diabetes or autoimmune disorders of the central nervous system such as stiff-man syndrome. It can appear with other pancreatic autoantibodies, such as insulin autoantibodies (IAA), presenting as early signs of pancreatic islet β-cells impairing, and play roles in the pathogenesis of type1 diabetes (T1D) and latent autoimmune diabetes in adults (LADA). Positive GAD65-Ab is rarely observed in insulin-dependent diabetic patients with other acquired autoimmune diseases, such as Sjogren's syndrome (SS). Besides, LADA revealed by islet autoantibodies such as GAD65-Ab can also be complicated with Hashimoto's thyroiditis (HT), another autoimmune thyroid disease. To date, whether GAD65-Ab positive in patients with autoimmune diseases predicts the onset or progression to T1D or LADA remains unknown. Herein, two unique cases of middle-aged Chinese Han women free from diabetes for three years are described despite their blood tests persistently testing positive for GAD65-Ab or IAA. Both patients suffered from HT and SS. Follow-up OGTTs (oral glucose tolerance test) for three years revealed that the patients had a well-controlled glycemic level and normal pancreatic function. However, one of the patients had a temporary increase of postprandial glucose after a short-term loss of diet control. The presence of auto-immune antibodies in these patients had little impact on glucose tolerance or insulin secretion in 3 years. The study postulate that both the primary immune injury caused by serum GAD65-Ab positive, an autoimmune marker, and increased body weight contribute to the progression of LADA.

Immunogenicity and Efficacy of Insulin Glargine Biosimilar Ezelin versus Originator Insulin Glargine in Patients with Type 2 Diabetes

PURPOSE

To compare the immunogenicity and efficacy of insulin glargine biosimilar Ezelin (EZL) versus originator insulin glargine Lantus (LAN) as a reference basal insulin in patients with type 2 diabetes (T2D).

PATIENTS AND METHODS

This was a randomized, multicenter, open-label, 24-week study in insulin-naïve patients with T2D, with HbA1c of >7.0%. We randomly assigned 133 eligible patients to receive either EZL or LAN. Baseline characteristics, including insulin autoantibody (IAA), zinc transporter 8 (ZnT8) antibody, HbA1C, fasting plasma glucose (FPG), 2-hour postprandial plasma glucose (2hPPG), AST, ALT, BUN, eGFR, and oral antidiabetic drugs, were obtained before starting insulin treatment. After starting treatment, insulin dose was titrated to achieve FPG target along with oral antidiabetic drugs. Patients were given home glucometer and assisted to record plasma glucose measurement and adverse event (AE). Every month, patients came to the diabetes clinic and performed a regular physical examination and intensifying treatment if needed. Out of the 133 randomized patients, only 122 completed the study and can be examined for their IAA and ZnT8 after 6 months of treatment. The study was registered in clinicaltrials.gov, NCT03352674.

RESULTS

There is a similar proportion of patients with changes of IAA from baseline: 1 out of 58 (1.7%) patients receiving EZL versus 1 out of 64 (1.6%) patients receiving LAN (p = 1.000). One patient in the EZL group (1.7%) versus none in the LAN group experienced a change of ZnT8 antibody from baseline. Similar glucose control in EZL versus LAN was determined by the change in HbA1c, FPG, and 2hPPG (-2.0%, -67.46 mg/dL, and -76.51 mg/dL in the EZL group versus -1.7%, -58.11 mg/dL, and -70.03 mg/dL in the LAN group). There were six events of documented hypoglycemia in the EZL group versus five events in the LAN group. No patients experienced diabetic ketoacidosis during the study.

CONCLUSION

Overall, insulin glargine biosimilar EZL and originator insulin glargine LAN have shown a similar immunogenicity profile, as well as efficacy in providing glucose control and safety findings in T2D populations.

Glutamic Acid Decarboxylase Autoantibody-negative Slowly Progressive Type 1 Diabetes Mellitus: A Case Report and Literature Review

A 59-year-old non-obese Japanese woman developed diabetes mellitus with a negative glutamic acid decarboxylase autoantibody (GADA) test result. Her hyperglycemia was initially well controlled by oral hypoglycemic agents; however, despite continued treatment the hyperglycemia gradually worsened. As she had endogenous insulin deficiency and tested positive for insulin autoantibody (IAA), insulin therapy was initiated. Few studies have investigated GADA-negative patients with slowly progressive type 1 diabetes mellitus (SPT1D). Our IAA-positive SPT1D patient progressed from the clinical onset of diabetes mellitus to starting insulin therapy relatively quickly (1.5 years), similarly to other previously reported non-obese patients with GADA-positive SPT1D.

Insulin autoimmune syndrome: Three case reports

RATIONALE

Insulin autoimmune syndrome (IAS) is a rare endocrine disease characterized by repeated fasting hypoglycemia or episodes of hypoglycemia late after meals, elevated serum insulin, and positivity for insulin autoantibody (IAA) or insulin receptor antibody (IRA). We summarize the clinical manifestations and treatment experiences of 3 patients with IAS.

PATIENT CONCERNS

One patient with >20-year history of type 2 diabetes mellitus had irregular episodes of hypoglycemia 2 years of after treatment with insulin. Another patient with a 6-year history of type 2 diabetes mellitus presented irregular episodes of hypoglycemia after 6 months of treatment with insulin. One patient with a history of Graves' disease showed hypoglycemia after administration of thiamazole.

DIAGNOSIS

Serum islet cell antibody (ICA) and glutamic acid decarboxylase antibody (GADA) were negative, while antibody insulin autoantibodies were positive in all the 3 patients. Two patients demonstrated diabetes mellitus after an oral glucose tolerance test, while one had normal glucose tolerance. Furthermore, serum insulin levels significantly elevated and did not matched C peptide levels. No abnormalities were found on enhanced MRI of the pancreas, and all 3 patients were clinically diagnosed with IAS.

INTERVENTIONS

In case one, insulin aspart 30 injection was withdrawn after admission. In addition, the patient was prescribed sublingual acarbose 3 times daily. Two weeks after admission, prednisone acetate was administered orally once daily at night. In case 2, insulin aspart 30 injection was withdrawn after admission, the patient was prescribed sublingual acarbose 3 times daily with a meal. Five days after admission, oral prednisone acetate was administered once daily at night. In case 3, oral propylthiouracil was prescribed and thiamazole withdrawn after admission, and the patient consumed an extra meal before sleeping.

OUTCOMES

At the 3-month follow-up visit, the hypoglycemic episodes had disappeared, serum insulin levels were significantly decreased, and insulin antibody (IA) levels were no longer detectable in all 3 patients.

LESSONS

For those patients with high-insulin hypoglycemia, IAA should be evaluated if serum insulin concentrations are inconsistent with C peptide levels. Therapeutically, a lower dose of glucocorticoids with more appropriate medication timing can be used to achieve good results.

Autoantibodies against islet cell antigens in children with type 1 diabetes mellitus

We investigated the prevalence of glutamic acid decarboxylase 65 autoantibody (GADA), insulinoma-associated protein 2 autoantibody (IA2A), and insulin autoantibody (IAA) in 750 children with type 1 diabetes (T1D) living in Taiwan. GADA, IA2A, and IAA were measured by radioimmunoassay. The data were assessed by χ² test, binary logistic regression, and Spearman rank correlation. Of the 750 T1D patients, 66.3% had GADA, 65.3% IA2A, 35.7% IAA, and 17.2% no autoantibodies. The prevalence of GADA and IA2A significantly decreased along T1D duration. The positivity of either GADA or IA2A was 89.4% within the first year of disease and decreased to 36.7% after 9 years (P = 1.22 × 10^–20). Female patients had significantly higher prevalence of GADA compared with male patients (72.3% vs. 59.7%, P = 0.00027). The patients diagnosed before 12 years of age had a positive rate of 92.2% for either GADA or IA2A. Patients diagnosed at age 12 or above had a significantly lower positive rate of 81.6% (P = 0.011). GADA and IA2A significantly correlated with each other (rs = 0.245, P = 1.09 × 10^–11). We concluded that autoantibodies were detectable in 89.4% of T1D patients within one year after diagnosis. Their prevalence declined with disease duration. GADA was more prevalent in female patients. GADA and IA2A weakly correlated with each other.

Hypoglycemic coma due to insulin autoimmune syndrome induced by methimazole: A rare case report

Insulin autoimmune syndrome (IAS) is a rare cause of hypoglycemia characterized by the presence of insulin-binding autoantibodies and fasting or late postprandial hypoglycemia. The number of reports on the association of human leukocyte antigen (HLA) genotype with this disease in adolescents in China is limited. This is the case report of a 17-year-old female patient with Graves' disease who was treated with methimazole (MTZ). After 4 weeks of continuous MTZ treatment, the patient suffered an episode of unconsciousness during the late postprandial phase and was admitted to the hospital, where the blood glucose level was found to be 2.88 mmol/l. The symptoms were relieved following intravenous glucose administration. Imaging studies of the pancreas were unremarkable, but the laboratory investigations on admission revealed high serum levels of total insulin, associated with relatively low levels of free insulin and markedly elevated insulin autoantibody (IAB) levels. HLA testing revealed DRB1*0406/0901 and the patient discontinued MTZ and was prescribed propylthiouracil. During the long-term follow-up, the total insulin and IAB levels gradually declined. There was no other episode of hypoglycemia. Therefore, in adolescents with Graves' disease receiving antithyroid treatment with MTZ who experience hypoglycemia, the IAB levels should be assessed to exclude or confirm IAS as the underlying cause.