Diabetes Mellitus I PDF

Diabetes Mellitus By Dr. Dina Rasheed Issa Lecturer of Internal Medicine (Diabetes & Endocrinology)  Objectives: Define diabetes mellitus. Discuss the prevalence of diabetes both globally and locally. Classify the different disorders of glycemia. Understand the differ...

Diabetes Mellitus By Dr. Dina Rasheed Issa Lecturer of Internal Medicine (Diabetes & Endocrinology)  Objectives: Define diabetes mellitus. Discuss the prevalence of diabetes both globally and locally. Classify the different disorders of glycemia. Understand the difference between Type 1 and Type 2 diabetes in relation to the clinical presentation, patient characteristics and pathogenesis. Identify the laboratory investigations used to diagnose diabetes. Identify treatment regimens for diabetes.  Definition Diabetes mellitus is a syndrome with disordered metabolism and inappropriate hyperglycemia due to either a deficiency of insulin secretion or to a combination of insulin resistance and inadequate insulin secretion to compensate for the resistance.  Epidemiology Diabetes is one of the leading causes of morbidity, which results in huge health and financial burden worldwide. IDF listed Egypt among the world top 10 countries in the number of patients with diabetes. It is expected that the number of patients with diabetes in the Middle East and North Africa (MENA) region to grow by 86% from year 2019 to 2045 or from 54.8 million to 107.6 million with number of 223.3 thousands deaths due to diabetes before the age of 60 years. In Egypt, the prevalence of diabetes is around 20.9% among adults between 20 and 79 years of age (IDF,2021)  Classification & Pathogenesis I. Type 1 diabetes (beta cell destruction, usually leading to absolute insulin deficiency) A. Immune mediated B. Idiopathic II. Type 2 diabetes (may range from predominantly insulin resistance with relative insulin deficiency to a predominantly insulin secretory defect with insulin resistance) III. Other specific types of diabetes A. Genetic defects of beta cell function: (MODY 1- 6), Mitochondrial DNA B. Genetic defects in insulin action: Type A insulin resistance, Leprechaunism, Rabson-Mendenhall syndrome, Lipodystrophy syndromes.  Classification & Pathogenesis C. Diseases of the exocrine pancreas: pancreatitis, pancreatectomy, neoplasia, cystic fibrosis, hemochromatosis. D. Endocrinopathies: acromegaly, Cushing’s syndrome, glucagonoma, pheochromocytoma, hyperthyroidism, somatostatinoma. E. Drug or chemical induced: glucocorticoids F. Other genetic syndromes sometimes associated with diabetes (Down, Klinefelter, Turner) IV. Gestational diabetes mellitus (GDM): diabetes diagnosed in the second or third trimester of pregnancy that was not clearly overt diabetes prior to gestation.  Insulin Resistance Syndrome (Metabolic Syndrome)  It consists of a constellation of metabolic abnormalities that confer increased risk of cardiovascular disease and diabetes mellitus. The major features of the metabolic syndrome include central obesity, hypertriglyceridemia, low high-density lipoprotein (HDL) cholesterol, hyperglycemia, and hypertension.  Prediabetes It is the term used for individuals whose glucose levels do not meet the criteria for diabetes but are too high to be considered normal  Clinical features: A. Symptoms and Signs Type 1 diabetes: Clinical presentation can vary from non-emergency presentations (polydipsia, polyuria, enuresis, chronic weight loss or failure to gain weight in a growing child) to severe dehydration, frequent vomiting, acetone detected on the breath and hyperventilation of diabetic ketoacidosis, and shock. Type 2 diabetes: asymptomatic initially, polydipsia, polyuria, chronic skin infections, vaginitis, overweight or obesity, Acanthosis nigricans. Occasionally, patients with type 2 diabetes may have evidence of neuropathic or cardiovascular complications at the time of presentation. B. Laboratory Findings Plasma glucose Oral glucose tolerance test Glycated hemoglobin (HbA1c, A1C) measurements Urine glucose Urine and blood ketones C. Investigations of complications Criteria for the diagnosis of diabetes. Clinical characteristics of type 1 diabetes, type 2 diabetes, and monogenic diabetes  Treatment Regimens A. Lifestyle Modification: MNT, Physical activity. B. Medications for Treating Hyperglycemia 1. Medications that primarily stimulate insulin secretion by beta cell: Sulfonylureas, Meglitinide Analogs 2. Medications that primarily lower glucose levels by their actions on the liver, muscle, and adipose tissue: Metformin, Thiazolidinediones, 3. Medications that affect absorption of glucose: Acarbose 4. Incretins: gut hormones (glucose dependent insulinotropic peptide (GIP) and glucagon-like peptide-1(GLP-1): GLP-1 receptor agonists, DPP-4 inhibitors 5. Sodium-glucose co-transporter 2 inhibitors C. Insulin Insulin preparations: Bioavailability characteristics of the insulins:  Management: D. Transplantation: 1. Pancreas transplantation 2. Islet transplantation