Diabetes Mellitus Overview

Diabetes Mellitus

• Chronic multisystem disease with hyperglycemia caused by abnormal insulin production (type 1), impaired insulin utilization (type 2), or both.
• 8th leading cause of death in the US.
• Leading cause of end-stage renal disease, adult blindness, and non-traumatic lower limb amputations.

Risk Factors

• Family history
• Gestational diabetes
• Minority groups (American Indians, African Americans, Hispanics, Asian Americans)
• Age over 35
• Obesity (BMI over 30)
• Having given birth to an infant over 9 lbs
• Inactivity

Etiology and Pathophysiology

• Combination of genetic, autoimmune, and environmental factors.
• Primarily a disorder of glucose metabolism related to insufficient or ineffective insulin.
• Insulin, produced by beta cells in the islets of Langerhans, promotes glucose transport into cells.
• Counterregulatory hormones like glucagon, epinephrine, growth hormone, and cortisol work against insulin, increasing glucose levels.

Prediabetes

• At risk for type 2 diabetes.
• Defined as impaired glucose tolerance (IGT), impaired fasting glucose (IFG), or both.
• IGT is diagnosed with a 2-hour oral glucose tolerance test (OGTT) value of 140-199 mg/dL.
• IFG is diagnosed with a fasting glucose level of 100-125 mg/dL.
• Usually asymptomatic.

Type 1 Diabetes

• Insulin-dependent (abnormal insulin production).
• Result of destruction of beta cells in the pancreas, the only cells that produce insulin.
• Signs and symptoms: polydipsia, polyuria, polyphagia, fatigue/weakness, nausea/vomiting.
• Treatment requires both long-acting and short-acting insulin.

Type 2 Diabetes

• Insulin-resistant (impaired insulin utilization).
• Combination of inadequate insulin secretion and insulin resistance.
• The pancreas usually produces some insulin, but it may not be enough or used effectively.
• Signs and symptoms: slow onset with possible polyuria and polydipsia.

Insulin Therapy

• Usually available as U100 insulin (1 mL contains 100 units of insulin).
• Inject at a 45-90-degree angle.
• Wash injection sites with soap and water, not alcohol swabs.

Insulin Pump

• Delivers continuous subcutaneous insulin infusion through a small device.
• Delivers short-acting insulin.
• Preprogrammed to deliver varying hourly basal rates.
• Ideal candidates are individuals who have failed other regimens, pregnant women, or those wanting flexibility.
• Expensive, with a risk for infection at the site.
• Infusion site needs to be changed every 24-48 hours.

Problems with Insulin Therapy

• Hypoglycemia: Treatment includes administering glucagon and carbohydrates.
• Allergic Reaction: Local inflammatory reactions may occur around the injection site.
• Lipodystrophy: Changes in subcutaneous tissue may occur with frequent use of the same injection site.
• Somogyi Effect: Rebound hyperglycemia in the morning due to a high insulin dose at night.
• Dawn Phenomenon: Hyperglycemia on awakening due to counterregulatory hormones.

Acute Complications

• Diabetic Ketoacidosis (DKA): Serious condition caused by a profound insulin deficiency. Characterized by hyperglycemia, ketosis, acidosis, and dehydration.

### Hyperparathyroidism

• Most common disease of the parathyroid glands.
• Characterized by excess parathyroid hormone (PTH) and high blood calcium levels.
• Most commonly caused by a benign tumor called an adenoma on a parathyroid gland.
• Symptoms: kidney stones, abdominal pain, bone and joint pain, fragile bones, irritability, depression, anxiety, heart palpitations, arrhythmias.

### Diagnostic Studies (Hyperparathyroidism)

• Serum PTH: Increased
• Serum Calcium: Increased (8.5-10 mg/dL)
• Serum Phosphate: Decreased (2.5-4.5 mg/dL)
• Urine Calcium: Increased
• Bone Density: Decreased

### Management (Hyperparathyroidism)

• Surgical: Partial or complete removal of the parathyroid glands.
• Non-surgical: Monitoring of lab values, exercise, increased fluids, moderate calcium intake, medications like calcimimetic agents, bisphosphonates, and phosphate.
• Severe: IV sodium chloride, loop diuretics, IV bisphosphonates.

### Nursing Management (Hyperparathyroidism)

• Patient education.
• Postoperative monitoring for pain, bleeding, and tetany (due to sudden decrease in calcium).

### Hypoparathyroidism

• Very rare condition characterized by inadequate circulating PTH.
• Most commonly caused by iatrogenic factors (accidental removal or damage during neck surgery).

Symptoms (Hypoparathyroidism)

• Due to hypocalcemia: tetany, tingling lips, stiffness of limbs, muscle spasms, Trousseau's sign, Chvostek's sign.

### Diagnostic Studies (Hypoparathyroidism)

• Serum PTH: Decreased (10-65 pg/mL)
• Serum Calcium: Decreased
• Serum Phosphate: Increased (2.5-4.5 mg/dL)

### Management (Hypoparathyroidism)

• Calcium supplements, vitamin D, magnesium, high calcium diet.
• Treatment goals are to treat acute complications, maintain normal calcium levels, and prevent long-term complications.
• Give IV calcium slowly with ECG monitoring.

Thyroid Gland

• Located in the front of the neck.
• Produces thyroid hormone, which controls metabolic rate, metabolism, and growth/development.
• Thyroid hormones: calcitonin (regulates calcium), T3 (regulates metabolism), T4 (regulates metabolism).
• Iodine deficiency can prevent the thyroid from secreting sufficient thyroid hormone.
• TSH (thyroid stimulating hormone) is released from the pituitary gland, stimulating the thyroid to release T3/T4.

### Hypothyroidism

• Condition in which the thyroid gland produces inadequate amounts of thyroid hormone.
• Primary hypothyroidism: Thyroid gland malfunction. Causes: insufficient iodine, Hashimoto's disease, surgical removal, therapeutic radiation, atrophy, tumors.
• Secondary hypothyroidism: Related to pituitary tumors or disorders, affecting the hypothalamic-pituitary axis.

### Clinical Manifestations (Hypothyroidism)

• Fatigue, weight gain, cold intolerance, constipation, dry skin, thinning hair, periorbital edema.

### Myxedema Coma

• Severe hypothyroidism with loss of brain function due to prolonged low thyroid hormone.
• Life-threatening.

Explore the intricate details of Diabetes Mellitus, including its causes, risk factors, and impact on health. Understand the differences between type 1 and type 2 diabetes, along with their etiology and pathophysiology. This quiz sheds light on the seriousness of this chronic disease and its complications.