OVERVIEW

What is insulin resistance?

Insulin has the effect of lowering blood sugar and maintaining stable blood sugar levels. Insulin resistance refers to the reduced effectiveness of insulin, where the body responds poorly to normal concentrations of insulin, which may be accompanied by high blood sugar.

Insulin resistance is not a standalone disease but rather a phenomenon that can occur in various conditions. It may be observed in the following groups:

• Diabetic patients treated with animal-derived insulin (now rarely used);

• Type 2 diabetes patients;

• Patients with polycystic ovary syndrome, metabolic syndrome, hyperlipidemia, acromegaly, Cushing's syndrome, or uremia;

• Obese individuals, those under stress, or pregnant women;

• Patients taking excessive glucocorticoids;

• Individuals with certain rare genetic disorders, such as leprechaunism;

• Patients with severe insulin resistance syndromes, such as Type B insulin resistance syndrome.

What is immune-mediated insulin resistance?

Immune-mediated insulin resistance is a special type of insulin resistance caused by immune factors. It may occur in conditions such as insulin antibodies, Type B insulin resistance syndrome, and ataxia-telangiectasia.

Is immune-mediated insulin resistance common?

It is relatively rare.

SYMPTOMS

What are the manifestations of immune insulin resistance?

Different types of immune insulin resistance present differently:

• Insulin antibodies: Mainly seen in diabetic patients injected with animal insulin (such as porcine or bovine insulin). Diabetic patients who develop insulin antibodies exhibit highly unstable blood sugar levels, fluctuating unpredictably, making it difficult for doctors to adjust insulin dosages based on blood sugar levels.

• Type B insulin resistance syndrome: Patients may experience hyperglycemia or fasting hypoglycemia. It is often associated with autoimmune thyroid diseases, diabetes, Addison's disease, systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, and other conditions. Blood tests show significantly elevated insulin levels and positive insulin antibodies or insulin receptor antibodies.

• Ataxia-telangiectasia: Symptoms include progressively worsening unsteady gait, lack of coordination, skin telangiectasia, recurrent respiratory infections, and possible elevated blood sugar. Blood tests show no insulin antibodies.

CAUSES

What are the causes of immune-mediated insulin resistance?

In general, the etiology of immune-mediated insulin resistance involves the presence or production of antibodies that interfere with insulin's normal function. Some antibodies bind to insulin itself, while others bind to insulin receptors, ultimately impairing insulin's effectiveness. Specifically:

• Insulin antibodies: Primarily observed in diabetic patients treated with animal insulin (e.g., porcine or bovine insulin). Since animal insulin differs significantly from human insulin, the body recognizes it as a "foreign substance," triggering antibody production to eliminate these "foreign" molecules.

• Type B insulin resistance syndrome: A severe form of insulin resistance caused by autoimmune dysfunction. The body produces antibodies targeting insulin receptors, which occupy receptor sites and prevent insulin from binding, resulting in severe insulin resistance.

• Ataxia-telangiectasia: Caused by low-molecular-weight IgG antibodies binding to insulin receptors.

DIAGNOSIS

##What tests do patients with immune insulin resistance need to undergo?{sort-2}

• Blood glucose, glycated hemoglobin, oral glucose tolerance test (OGTT), etc.: To determine the presence of hyperglycemia or hypoglycemia.

• Insulin and C-peptide: To assess for hyperinsulinemia, which is common in many insulin-resistant patients.

• Insulin antibodies, insulin receptor antibodies: Used to differentiate the types of insulin resistance.

• Antinuclear antibody profile, etc.: To evaluate for the presence of other autoimmune diseases. Type B insulin resistance is often associated with other autoimmune conditions.

TREATMENT

How to treat immune-mediated insulin resistance?

• Insulin antibodies: Discontinue animal insulin and switch to recombinant human insulin or insulin analogs.

• Type B insulin resistance syndrome: Mainly involves immunomodulatory therapy. Due to the rarity of this condition, there is limited research data on treatment, and a unified treatment standard is currently lacking. Doctors often rely on their clinical experience to prescribe medications such as glucocorticoids, plasmapheresis, cyclophosphamide, and cyclosporine. Additionally, metformin and insulin can be used to control blood sugar.

• Ataxia-telangiectasia: There is no specific treatment for the disease itself, only symptomatic and supportive care. For infections, aggressive use of anti-infective drugs is recommended; for interstitial lung disease, glucocorticoid therapy may be attempted. Overall, this disease is difficult to treat and has a poor prognosis.

DIET & LIFESTYLE

What should be paid attention to in daily life for immune insulin resistance?

For specific precautions, please refer to each disease.

PREVENTION

Can Immunological Insulin Resistance Be Prevented?

If it is caused by insulin antibodies produced due to injections of animal insulin, it can be prevented. Animal insulin is now rarely used to treat diabetes, so this situation has also decreased.

Other forms of immunological insulin resistance are difficult to prevent.