Lec. 1 Dr. Abdullah K. Rabba Ph.D Pathophysiology 1 PHCL 324 Lec. 1 Dr. Abdullah K. Rabba Ph.D

Objectives: Define Pathophysiology Understand and define related terminology: etiology, pathogenesis, clinical manifestations… Acute vs Chronic diseases Local vs systemic diseases Define homeostasis, epidemiology

Pathophysiology: The study of the functional changes that occur in the body as a result of an injury, or disease. (study of mechanisms of diseases)

Pathology: the study of changes in cells and tissues as a result of injury or disease. Physiology: the mechanisms of human body functioning

Understanding Pathophysiology Etiology Pathogenesis Clinical manifestations Diagnosis and treatment

Pathogenesis Is the sequence of cellular and tissue events that take place from the time of initial contact with an etiologic agent until the ultimate expression of the disease or Origination and development Disease Beginning

Example to understand pathogenesis In Diabetes Mellitus (DM) Pancreatic beta-cells destruction years Progression of beta-cell destruction Developing signs and symptoms

Disease: functional impairment of cells, tissues, organs, or organ systems. The term Diseases are used to include: injuries, disorders, illnesses, and syndromes. Syndrome: a specific condition with a recognizable, predictable pattern. Or a group of symptoms that together are characteristic of a specific disorder

Etiology Etiology: The cause of the disease Etiologic agents can be : biologic agents (bacteria), physical forces (burns), chemical agents (poison), nutritional excess or deficit If the etiology is unknown, the disease said to be idiopathic If the disease is a byproduct of medical diagnosis or treatment it is said to be iatrogenic

Clinical manifestations Clinical Manifestations are the presenting signs and symptoms. Sings and symptoms are terms used to describe the structural and functional changes that accompany a disease

Symptoms: are complaints reported by the patient or by someone else on behalf of the patient (Subjective manifestations) Sings: direct observation by an examiner (Objective Manifestations)

Symptoms: e.g. Pain, Dizziness, etc difficult to observe or measure Signs: e.g. High temperature, or blood pressure. measurable

Signs and Symptoms Local Systemic Local: Manifestations found at the site of disease, e.g local swelling or redness, pain. Systemic: Manifestations present throughout the body, e.g. fever, lethargy, and high BP.

Signs and Symptoms Acute Chronic Acute: begins abruptly and lasts a few days to a few months. (e.g. common cold) Chronic: insidious (gradual in onset). Lasts more than 6 months

With chronic diseases patients can have remissions (symptom-free periods) and exacerbations (flaring of symptoms)

Pathophysiology Terms Etiology Signs Pathogenesis Clinical Manifestations Mechanism of Disease Symptoms Diagnosis Treatment

Diagnosis and treatment Prognosis: the forecast or prediction of how the patient will proceed through the disease process. Excellent prognosis complete recovery Poor Prognosis increasing risk of morbidity and mortality. Morbidity: a negative outcome of disease that affects the quality of life. Mortality: Death of patient.

What is homeostasis? Homeostasis: is a dynamic balance in the body marked by the appropriate and effective response to stimuli, thereby, keeping the body in a steady state. Homeostasis is an important body goal.

What is epidemiology? The study of disease in populations in order to: Recognize where a disease is most widely spread. Recognize who is most affected by the disease. Discover why the disease is presenting in certain population Discover how to reduce the spread of disease

Incidence: is the rate of occurrence of a disease at any given time Incidence: is the rate of occurrence of a disease at any given time. (probability). E.g. incidence of Down Syndrome is 1 in 733. Prevalence: the number or percentage of a population that is affected by a particular disease at a given time. E.g. 400,000 people in the US are currently living with Down Syndrome.

Quiz Pathophysiology is------------------------ A patient wants to know what has caused his illness. This information is termed: A: Etiology B: Pathogenesis. C: Epidemiology. D: Nosocomia. Which of the following terms indicate the dynamic steady state that the body strives to achieve every day? A: Mortality B: Morbidity C: Homeostasis D: Health Pathophysiology is------------------------