Essential Medical Concepts: Diseases, Treatments, and Body Systems
Common Health Conditions
Malformations and Birth Defects
Malformations are conditions present at birth, resulting from disorders during embryonic development or childbirth.
Autoimmune Diseases
Autoimmune diseases are conditions where the immune system mistakenly attacks the body’s own tissues, producing molecules (antibodies) that cause damage to various organ systems. Examples include systemic lupus erythematosus, rheumatoid arthritis, and multiple sclerosis. Immunomodulator drugs can help control these diseases.
Multiple Sclerosis
Multiple sclerosis is a chronic disease of the central nervous system that affects the brain and spinal cord, specifically damaging the myelin sheath.
Endocrine, Nutritional, and Metabolic Diseases
These are disorders affecting the body’s hormones, nutrient processing, and metabolism. Examples include diabetes and obesity.
Cancer: Pathology and Treatment
Cancer is a disease characterized by the abnormal and uncontrolled reproduction of cells within body tissues. It is the second leading natural cause of death globally, after cardiovascular diseases. Common types of cancer include lung, colon, breast, prostate, and pancreatic cancer.
Invasiveness
The ability of cancer cells to penetrate and extend through adjacent tissues.
Metastasis
The ability of cancer cells to penetrate blood and lymphatic vessels, travel through the bloodstream or lymphatic system, and establish secondary tumors in other parts of the body.
Cancer Treatments
- Surgery
- Radiotherapy
- Chemotherapy
- Immunotherapy
- Hormonal Treatments
Respiratory and Cardiovascular Health
Obstructive Pulmonary Disease (OPD)
Characterized by narrowing or obstruction of the airways, which reduces the volume of air exhaled.
Restrictive Pulmonary Disease
Caused by a loss of lung elasticity, which reduces the total volume of air the lungs can hold.
Common Cardiovascular Conditions
- Stroke: Occurs when blood flow to the brain is interrupted, often due to a thrombus (blood clot).
- Arteriosclerosis: Characterized by the accumulation of cholesterol and fats on the inner walls of arteries, hindering blood flow.
- Common Symptoms: Difficulty breathing and oppressive chest pain.
Mental Health and Disorders
Mental diseases are disorders of the brain’s chemistry and function, characterized by abnormal or unreasonable disturbances in personality, thought, or behavior. Examples include:
- Eating disorders (e.g., anorexia, bulimia)
- Attention deficit syndrome
- Personality disorders
- Dementia
Pharmacology: Drug Classifications
Drugs are substances that affect the body’s function. They can be categorized as:
- Depressants: (e.g., alcohol, benzodiazepines)
- Stimulants: (e.g., cocaine, nicotine, caffeine)
- Hallucinogens: (e.g., psilocybin mushrooms, cannabis, ecstasy)
The Immune System and Immunity
The Immune System
The immune system comprises external and internal defenses that protect the body from foreign substances, or antigens, that penetrate its interior. These include:
- Barriers: Skin, mucous membranes, saliva, urine, tears, and other biological barriers.
Immunity
Immunity is the resistance exhibited by organisms to infections caused by pathogens or foreign substances. It can be innate (non-specific) or acquired (specific).
B Cells and T Lymphocytes
B lymphocytes recognize specific antigens and produce antibody proteins (immunoglobulins) that bind to them. T lymphocytes recognize antigens presented on infected cells and destroy those cells, preventing the pathogen from reproducing.
Key Medical Definitions
Antibiotics
Antibiotics are substances that destroy or inhibit the growth of bacteria, but are ineffective against viruses.
Antisera
Serum is the liquid component of blood, devoid of blood cells, but containing antibodies produced by the body to fight infections. An antiserum is a purified serum obtained from a person or animal that has developed antibodies against a specific infection or toxic substance.
Interferon
A protein synthesized by infected cells to inhibit the entry and replication of viruses in other cells.
Pandemic
A pandemic is a disease that affects a very large territory, such as a continent or the entire world. Historical examples include the Spanish Flu (a type of pneumonia) and avian influenza outbreaks. AIDS is also considered a global pandemic.