Exam Study Notes

Hyperthyroidism & Hypothyroidism

• Differences:

  • Thyroid Hormones (T3 & T4): Affect the basic metabolic rate.
  • Hypothyroidism: Deficiency in production & release of T3 & T4.
    • Causes:
      • Iodine deficiency.
      • Thyroiditis (autoimmune; autoantibodies lead to the destruction of thyroid cells).
      • Post-treatment (e.g., thyroidectomy) of hyperthyroidism can result in hypothyroidism.
      • Congenital.
  • Hyperthyroidism: Excess of T3 & T4 (HIGH).
    • Causes:
      • Graves’ disease – Autoimmune antibodies (TSI) stimulate TSH receptors on the thyroid gland.
      • Toxic multinodular goiter.
      • CA (Cancer) thyroid.
      • Excess in exogenous thyroid hormone (thyroxine replacement Tx).

• Signs & Symptoms (S&Sx):

  • Hypothyroidism:
    • Cold intolerance.
    • Decreased sweating.
    • Cardiovascular (CV): Slow heart rate (bradycardia).
    • Gastrointestinal (GI): Low motility leading to constipation.
    • Weight gain.
    • Goiter (overstimulation by TSH from pituitary).
    • Central Nervous System (CNS): Poor memory, slow thinking, depression.
    • Menstruation: Irregular & heavy periods.
  • Hyperthyroidism:
    • Heat intolerance.
    • Sweating.
    • Rapid heart rate (tachycardia); irregular.
    • High motility leading to “Diarrhea”; frequent bowel movement.
    • Weight loss despite good appetite.
    • Goiter (presence of nodules in the thyroid gland).
    • Irritable; anxiety.
    • Light; short periods.
    • Muscle weakness; osteoporosis.
    • Protruding eyeballs (Graves’ disease).

• Treatment (Tx):

  • Hypothyroidism:
    • Levothyroxine (natural form of thyroid hormone, T4) replacement.
    • Iodine supplement.
  • Hyperthyroidism:
    • Graves’ disease: Antithyroid drugs (inhibit the synthesis of thyroxine).
    • Removal or destruction of thyroid tissue: Surgery (thyroidectomy); radioactive iodine.

• Diagnosis (Dx):

  • Hypothyroidism:
    • Thyroid Function Test (TFT): ↑ TSH; ↓ T3 / T4.
    • Imaging: Ultrasound (US).
    • Test for autoantibodies against the thyroid gland.
  • Hyperthyroidism:
    • ↓ TSH; ↑ T3 / T4.
    • US.
    • Radioactive iodine (RI) uptake test.
    • Test for autoantibodies against TSH receptor (TSI).

Diabetes Mellitus (DM)

• Types:

  • Type 1 (T1DM)
  • Type 2 (T2DM)

• Causes:

  • T1DM (IDDM):
    • Onset: Childhood.
    • Autoimmune condition with genetic predisposition + environmental factors (e.g., viral infections).
  • T2DM (NIDDM):
    • Onset: Adulthood.
    • Metabolic syndrome: Overweight/obese.

• Pathophysiology:

  • T1DM:
    • Absolute deficiency in insulin due to the destruction of Beta cells of the pancreas.
  • T2DM:
    • Relative deficiency of insulin.
    • Insulin resistance / decreased sensitivity of insulin-dependent cell activities (despite higher normal production of insulin).
    • Decrease in production of insulin.
  • Insulin-Dependent Cellular Activities:
    • Glucose uptake by skeletal muscles, fat/adipose tissue (fat/adipose cells) & Utilization of glucose by skeletal muscles, fat tissues & liver → Hyperglycemia \Rightarrow glucosuria (presence of glucose in urine due to incomplete reabsorption of glucose by kidneys) \Rightarrow Ketone bodies formation \Rightarrow Breakdown of protein.
    • Hyperglycemia \Rightarrow Microvascular complications \Rightarrow kidneys, nerves & macrovascular complications (heart disease, stroke, peripheral vascular diseases, etc.).

• Signs & Symptoms (S&Sx):

  • T1DM & T2DM:
    • Hyperglycemia.
    • Glucosuria \Rightarrow polyuria (osmotic diuresis); dehydration; polydipsia.
  • T1DM:
    • Weight loss (glucose lost) \Rightarrow polyphagia.
    • Poor growth & development if not properly treated with insulin.
  • Both T1DM & T2DM:
    • UTI; genital itch
    • Neuropathy (nerve pain; abnormal sensations); Retinopathy (retina = nerves \Rightarrow vision).
    • Poor wound healing.
    • Poor immune response.
    • Foot infections \Rightarrow gangrene \Rightarrow amputations.

• Diagnosis (Dx):

  • Tests on blood glucose levels (Fasting blood glucose - ~ 8 hr fasting; Post-prandial; 2 hr after meals) & related glycation with cellular molecules (HbA1c).
  • Oral glucose tolerance test (OGTT).

• Treatment (Tx):

  • T1DM:
    • Insulin replacement therapy \Rightarrow Insulins of different onset (rapid onset) & duration of action \Rightarrow Try to mimic physiologic insulin response to glucose intake from diet.
  • T2DM:
    • Insulin replacement therapy.
    • Oral antidiabetic drugs to:
      • Stimulate secretion of insulin (e.g., sulfonylureas).
      • Increase sensitivity of insulin (e.g., metformin).
      • Increase excretion of urinary glucose (e.g., SGLT1 inhibitors).

Osteoporosis

• Causes and risk factors
• Signs and Symptoms
• Diagnostic methods
• Treatment options

Gout vs. Rheumatoid Arthritis (RA) vs. Osteoarthritis (OA)

• Causes & Risk Factors:

  • Gout:
    • KEY: Uric acid (the end metabolic product of purines – Adenine (A) & guanine (G) found in nucleic acids, RNA & DNA
    • Overproduction or under-secretion of uric acid.
    • Purine-rich foods.
    • Kidney failure \Rightarrow under-secretion.
  • RA:
    • Autoimmune arthritis + Extra-articular involvements (heart, rheumatoid nodules, etc.).
  • OA:
    • Degeneration of cartilage that normally cushions the articulating bones.
    • Overweight (stress to the weight-bearing joints).
    • Repeated joint injury.

• Pathophysiology:

  • Gout:
    • Hyperuricemia \Rightarrow Deposition of urate (uric acid) crystals in the affected joint.
    • Attraction of inflammatory cells to the joint & attempt to remove the crystals by inflammatory cells.
    • Intense inflammation \Rightarrow S&Sx.
  • RA:
    • Citrullination of proteins \Rightarrow Auto-Immune response.
    • Attraction of inflammatory cells to the joint \Rightarrow antibodies, response by T cells.
    • Destruction of the joint tissues (cartilage, bones) by invasion of inflamed synovium.
    • Permanent change in shape & functions of the affected joints.
  • OA:
    • Degradation by … from Inflammatory response within cartilage.
    • Rubbing of the 2 bones \Rightarrow bone erosion \Rightarrow pain & new bone growth (bone spurs / osteophytes).

• Signs & Symptoms (S&Sx):

  • Gout:
    • Acute during gouty attacks: Severe pain, swelling, redness, tenderness even from light touch.
    • Chronic: Presence of tophi (singular: tophus) in soft tissues.
  • RA:
    • Pain
    • Deformity of joints \Rightarrow range of motion / flexibility of joints & loss of joint functions.
    • Fatigue (anemia).
    • Weakness.
    • Rheumatoid nodules.
  • OA:
    • Pain & stiffness
    • Range of motion
    • Crepitus (grinding sensation when the affected joint moves).

• Diagnosis (Dx):

  • Gout:
    • Elevated uric acid levels in the blood.
    • Joint fluid examination.
    • Imaging: X-ray, US, DECT.
  • RA:
    • Anti-CPP antibodies / RF (antibodies).
    • Inflammatory indices: CRP; ESR.
    • Joint fluid exam.
    • CBC: Anemia.
    • Imaging: X-ray; MRI.
    • Lab tests.
  • OA:
    • Arthroscopy
    • X-ray; MRI

• Treatment (Tx):

  • Gout:
    • Lifestyle.
    • Acute: Anti-inflammatory & pain relief
      • Colchicine (anti-inflammatory).
      • Corticosteroid (anti-inflammatory) / NSAID (anti-inflammatory & pain killing).
    • Chronic: Reduction of uric acid
      • Inhibition of uric acid production.
      • Increase urinary excretion.
  • RA:
    • Inflammation & Pain relief – SHORT term
      • NSAID / Corticosteroids
    • Disease-modifying that helps to slow down or even prevent permanent joint damage – Long- term
      • DMARDs (e.g., methotrexate).
      • Biologics for inhibiting different inflammatory cytokines.
    • Surgery – Different methods
  • OA:
    • Pain relief
    • Drug & non-drug
    • Weight control if overweight
    • Surgery – Different methods

Uterine Fibroid (Leiomyoma)

• Uterine Fibroid (子宮肌瘤)
  • Risk factors
  • Signs and symptoms
  • Diagnostic methods
  • Treatment options

Cervical Cancer

• Cervical Cancer (子宮頸癌)
  • Risk factors
  • Signs and symptoms
  • Diagnostic methods
  • Treatment options
  • Preventive measures

Breast Cancer

• Breast Cancer (乳癌)
  • Causes
  • Risk factors
  • Signs and symptoms
  • Diagnostic tests
  • Treatment options

Benign Prostatic Hyperplasia (BPH)

• Benign Prostatic Hyperplasia (BPH) (良性前列腺增生)
  • Signs and symptoms/ Clinical manifestations of BPH
  • Diagnostic tests for BPH

Uterine Fibroid (Leiomyoma), Cervical CA, Breast CA Comparison

• Locations:

  • Uterine fibroid: Uterus = Myometrium (muscle layer of the uterus).
  • Cervical CA: Cervices of the Uterus.
  • Breast CA: Epithelium cells of the breast tissue.

• Cause:

  • Uterine fibroid: --
  • Cervical CA: HPV (high risk strains, e.g., HPV 16 & 18).
  • Breast CA: Growth factors, including estrogen, etc. Genetic mutations: Oncogene (e.g., HER2, c- Myc) & tumor suppressor genes (e.g., p53, BRCA1, BRCA2).

• Risk Factors:

  • Uterine fibroid: Estrogen/progesterone fluctuation.
  • Cervical CA: HPV + other risk factors (such as sexual activity).
  • Breast CA: Reproductive factors, Hormonal factors, Environmental, familial & genetics, Others.

• Signs & Symptoms (S&Sx):

  • Uterine fibroid: Depending on the type (locations of the fibroid & sizes). Uterine bleeding, Pain, Related symptoms related to adjacent organs (bladder & rectum) due to pressure from the fibroid mass, Infertility.
  • Cervical CA: Staging: I, II, III, & IV. S&Sx of Metastasis - Organ/tissue involved. Vaginal bleeding – Different manifestations. Discharge; pain; anemia. Related symptoms related to adjacent organs (bladder & rectum) in advanced stages (spread).
  • Breast CA: Palpable mass in breast. Physical changes in breast, such as … Pain.

• Diagnosis (Dx):

  • Uterine fibroid: Medical Hx, Physical examination – Bimanual pelvic exam, Hysteroscopy; Imaging: US, MRI.
  • Cervical CA: PAP test / HPV test, Colposcopy, CT & PET scan for metastasis, Etc.
  • Breast CA: Imaging: Mammogram, US. Biopsy. Status of Hormone receptors & HER2 – Molecular profiling.

• Treatment (Tx):

  • Uterine fibroid: Conservative Tx in early stage. Medical Tx - Hormonal, NSAID, Tranexamic acid. Surgery - Different methods.
  • Cervical CA: Solid CA \Rightarrow Surgery (depending on the stage of the CA) \Rightarrow Different methods & extents \Rightarrow Radiotherapy \Rightarrow Chemotherapy \Rightarrow Palliative care (to keep the patient as comfortable as possible) when cure is not possible.
  • Breast CA: Solid CA \Rightarrow Surgery – Different extents \Rightarrow Radiotherapy \Rightarrow Chemotherapy \Rightarrow Hormonal therapy (e.g., Tamoxifen, Aromatase inhibitors, such as letrozole) \Rightarrow Targeted therapy (e.g., HER2) \Rightarrow Palliative care.

• Prevention:

  • Uterine fibroid: --
  • Cervical CA: Reduction of sexual contacts. Screening (early detection). Vaccination against HPV (most effective is before contraction).
  • Breast CA: --