Type B insulin resistance syndrome with fasting hypoglycemia and postprandial hyperglycemia

Clinical characteristics of insulin resistance syndromes: A nationwide survey in Japan

AIMS/INTRODUCTION

Insulin resistance syndrome (IRS) of type A or B is triggered by gene abnormalities of or autoantibodies to the insulin receptor, respectively. Rabson-Mendenhall/Donohue syndrome is also caused by defects of the insulin receptor gene (INSR), but is more serious than type A IRS. Here, we carried out a nationwide survey of these syndromes in Japan.

MATERIALS AND METHODS

We sent questionnaires to a total of 1,957 academic councilors or responsible individuals at certified facilities of the Japan Diabetes Society, as well as at the department pediatrics or neonatology in medical centers with >300 beds.

RESULTS

We received 904 responses with information on 23, 30 and 10 cases of type A or B IRS and Rabson-Mendenhall/Donohue syndrome, respectively. Eight cases with type A IRS-like clinical features, but without an abnormality of INSR, were tentatively designated type X IRS, with five of these cases testing positive for PIK3R1 mutations. Fasting serum insulin levels at diagnosis (mean ± standard deviation) were 132.0 ± 112.4, 1122.1 ± 3292.5, 2895.5 ± 3181.5 and 145.0 ± 141.4 μU/mL for type A IRS, type B IRS, Rabson-Mendenhall/Donohue syndrome and type X IRS, respectively. Type A and type X IRS, as well as Rabson-Mendenhall/Donohue syndrome were associated with low birthweight. Type B IRS was diagnosed most frequently in older individuals, and was often associated with concurrent autoimmune conditions and hypoglycemia.

CONCLUSIONS

Information yielded by this first nationwide survey should provide epidemiological insight into these rare conditions and inform better healthcare for affected patients.

The insulin autoimmune syndrome (IAS) as a cause of hypoglycaemia: an update on the pathophysiology, biochemical investigations and diagnosis

Insulin autoimmune syndrome (IAS) is considered to be very rare in Caucasians. Understanding its pathophysiology is paramount in (a) appreciating its potential impact on analyses of pancreatic hormones and (b) explaining its highly variable clinical manifestations in non-diabetic, non-acutely ill patients with indeterminate hypoglycaemia. The underlying aetiology of IAS is the presence of variable affinity/avidity endogenous insulin antibodies in significant amounts. The two types of insulin antibodies namely antibodies which bind insulin and/or proinsulin(s) and receptor antibodies (insulin mimetic) will be discussed. Their biochemical and immunological roles in causing hypoglycaemia will be highlighted. Clinical manifestations of IAS can vary from mild and transient to spontaneous, severe and protracted hypoglycaemia necessitating in extreme cases plasmapheresis for glycaemic control. Antibodies of IAS can interfere in pancreatic immunoassay tests causing erroneous and potentially misleading results. Thorough testing for endogenous insulin antibodies must be considered in the investigations of non-diabetic, non-acutely ill patients with indeterminate and/or unexplained hypoglycaemia.

The effects of liraglutide on both hypereosinophilic insulin allergy and the characteristics of anti-insulin antibodies in type 2 diabetes mellitus: a case report

Background

Liraglutide is one of the glucagon-like peptide-1 analogs; there are only a few reports of liraglutide being used for the treatment of insulin allergy. Furthermore, anti-insulin immunoglobulin G antibodies are occasionally detected in patients with diabetes. Hence, we report a case in which switching to liraglutide therapy ameliorated both the symptoms of insulin allergy with hypereosinophilia and the characteristics of insulin antibodies in a patient with type 2 diabetes mellitus.

Case presentation

We present the case of a 70-year-old Japanese man with type 2 diabetes who developed insulin allergy with hypereosinophilia. Anti-insulin antibodies, high glycated hemoglobin levels (approximately 12 %), and high serum insulin levels were detected. Because a change in his insulin treatment was inefficient, treatment with liraglutide to protect residual insulin secretion was started, resulting in improvements in his insulin allergy, serum glycated hemoglobin, insulin, and eosinophil levels. Scatchard plots revealed decreased binding capacity and increased affinity constant for high affinity sites of anti-insulin antibodies.

Conclusions

Liraglutide might be useful for treating insulin allergy and anti-insulin antibodies in patients with type 2 diabetes.