Beginnings of Medicine

• Chinese traditional medicine is over 5000 years old

• Sumerians and Egyptians knew about disease states and had healers and specialists.

• Diseases were thought to be caused by bad spirits, worms, and decay or as a punishment from the gods.

• Greece is considered the cradle of modern Western medicine.

• Greek physicians learned through observations and critical thinking.

  • No scientific method was used, no autopsies, and no human anatomic studies.

• Medicine revolved around the 4 humors: Blood, phlegm, yellow bile, and black bile.

  • When one of these was an off-balance that’s when you got sick.

Noteworthy Doctors

Imhotep

• Imhotep: his name means the one who comes in peace, lived around 2650 BC, he was a pyramid builder the physician to the pharaoh.

• Credited as the author of the Edwin Smith Papyrus which describes trauma, surgery, anatomy, diagnosis, and treatment of 48 conditions.

• The Edwin Smith Papyrus is the earliest writing on medicine and rejects magic in favor of the science of healing.

Hippocrates

• Hippocrates: (460-377 BC) founded a school for physicians whose writings have been preserved, credited with the Hippocratic Oath (Do No Harm), and the 4 humor theory.

Roman Doctors

• Celsus: a Roman, who identified the cardinal signs of inflammation, translated the work “cancer” (crab-like growth) described by Hippocrates, and wrote, “De Medicina” which describes surgery, diet, pharmacy, etc.

• Galen: considered the GOAT physician, a gladiator physician whose writings were used for 1500 years, worked for Claudius Aurelius and his son, was the 1st to describe that arteries were filled with blood and not air, that urine is produced by the kidneys, that the spinal cord and nerves control muscle function, that the heart is the origin of blood vessels, and that sensory nerves are not motor nerves. Did studies on monkeys since autopsies on humans were illegal in Rome. Medicine did not advance past him until the renaissance.

Honorable Mentions

• Da Vinci: learned through human dissection about muscles, tendons, and bones

• William Harvey: discovered that blood is moved through the body by the heart

• Rudolf Virchow: introduced the concept of cellular pathology (diseases arise from alterations within cells or tissues) using microscopic observation and discovered Leukemia, pulmonary embolism (PE), termed embolism, connected the supra-clavicle muscle to gastric cancer.

• Edward Jenner: Introduced the 1st systemic vaccine, and discovered that cowpox (vaccinia) could protect against smallpox.

• Ignaz Semmelweis: (1818-1865) (“Savior of Mothers”) known for sanitation, and washing hands between clinical settings, compared childbed fever in maternity wards staffed by midwives vs. doctors.

• Robert Koch: founder of Modern Bacteriology

• Louis Pasteur: Known for principles of vaccinations, fermentation, pasteurization, and rabies vaccine.

• Sigmund Freud: Father of Psychoanalysis

• Joseph Lister: created antiseptics, and used phenol to sterilize instruments, wounds, and dressings.

• George Papanicolav: discovered the PAP smearing technique to diagnose cervical cancer early.

• Alexander Flemming: discovery of Penicillin, research on lysozyme, noticed P. Notatim inhibited the growth of Staph A.

Basic Principles of Human Disease

• Diseases in the broadest sense are undesired deviations from the norm.

• Some diseases are predetermined (genetic defects).

• Some are acquired (traumas, infection, degenerative).

• Some can be seen by the eye (jaundice).

• Some are visible only through medical testing, imaging (pigmentation/inclusion), or microscopic methods (urine proteins).

Signs vs. Symptoms

• Signs: Seen by the doctor or detected by clinical test (fever, blood pressure)

• Symptoms: Reported by the patient and cannot be measured (pain, drowsiness, vertigo)

4 pillars of Understanding

1. Disease etiology - the cause of the disease (infection, injury, genetic defects)

2. Pathogenesis - disease process

   1. Example - Streptococcus infects the lung → lung damage, inflammation, fluid accumulation

3. Lesion - morphological changes or ultrastructural changes in the affected tissue

4. Functional changes - the impaired function of an organ system, clinical manifestation

Recognizing Disease (Pathological Alterations)

1. Reported by the patient (pain, nausea)

2. Gross Examination - alteration (lesion) is visible by the naked eye (physical exam, autopsy)

3. Histological Examination - alterations are visible by a microscope

4. Laboratory Examination - blood test, urine sample, DNA testing

5. Specialized Examination - x-ray, ultrasound, endoscopy, MRI

Inflammation

• Signs of Inflammation: Calor (heat), Dolor (pain), Rubor (redness), Tumor (swelling), function laesa (impaired function)

Phases of Acute Inflammation

• (0-4 hrs) - Preformed factors, antibodies, serum factors, vasoactive factors (Rubor and Calor)

• (4-48 hrs) - an influx of neutrophils, rubor calor, dolor, tumor

• (48-96 hrs) - macrophages, all 5 signs of inflammation

• (>96 hrs) - Adaptive immunity, T-cells are activated and migrate to inflammatory sites (dolor, tumor, function laesa)