Q.31 Identify the autoimmune diseases among the following
(A) Type II Diabetes Mellitus (B) Type I Diabetes Mellitus
(C) Gestational Diabetes (D) Pernicious Anaemia

Type I Diabetes Mellitus and Pernicious Anaemia are autoimmune diseases among the options. Type II Diabetes Mellitus and Gestational Diabetes are not primarily autoimmune conditions.​

Option Analysis

Type II Diabetes Mellitus (A)
Type II diabetes results from insulin resistance and relative insulin deficiency, driven by lifestyle, obesity, and genetic factors rather than immune-mediated destruction of beta cells. No autoantibodies target pancreatic cells as in autoimmune diseases.​

Type I Diabetes Mellitus (B)
Type I diabetes is a classic autoimmune disease where T-cells and autoantibodies destroy insulin-producing pancreatic beta cells, leading to absolute insulin deficiency. It often associates with other autoimmune conditions like thyroiditis.​

Gestational Diabetes (C)
Gestational diabetes arises from pregnancy-induced insulin resistance and hormonal changes, not autoimmunity. While rare cases show autoantibodies (less than 10%), it lacks consistent immune-mediated beta cell destruction.​

Pernicious Anaemia (D)
Pernicious anaemia is an autoimmune disorder where antibodies attack gastric parietal cells or intrinsic factor, preventing vitamin B12 absorption and causing megaloblastic anaemia. It links to other autoimmune diseases like Type I diabetes.​

Autoimmune diseases Type I Diabetes Pernicious Anaemia represent key examples where the immune system attacks self-tissues, crucial for CSIR NET Life Sciences preparation. Understanding distinctions from non-autoimmune conditions like Type II and Gestational Diabetes aids exam success.​

Pathophysiology

In autoimmune diseases Type I Diabetes Pernicious Anaemia, autoantibodies drive tissue damage: beta cell destruction in Type I diabetes elevates blood glucose, while anti-parietal cell antibodies in pernicious anaemia block B12 absorption. Both show genetic links (HLA genes) and polyglandular syndromes.​

Clinical Features

• Type I Diabetes: Sudden onset polydipsia, polyuria, weight loss; ketoacidosis risk.

• Pernicious Anaemia: Fatigue, glossitis, neuropathy; macrocytosis on blood smear.
  Non-autoimmune contrasts: Type II involves gradual insulin resistance; gestational resolves post-delivery.​

Diagnosis and Management

Screen with autoantibodies (anti-GAD/IA-2 for Type I; anti-IF/parietal for pernicious). Lifelong insulin for Type I; B12 injections for pernicious. CSIR NET emphasizes these immune mechanisms.​