Disease Processes & Terminology

What is health?

When the body performs vital functions normally

What does health depend on?

Homeostasis

What is Homeostasis?

Process used to maintain relatively stable internal conditioners under changing environmental conditions

What 4 things are regulated through homeostasis?

Temperature, pH, blood composition, and fluid levels

What does the body when fluctuations occur?

Correct them before they threaten your health

What can homeostasis be used for?

Recognizing and describing disease more precisely

What does a significant disturbance in homeostasis indicate?

A disease

What is a disease?

Disorder of structure or function in the body (dis - ease, so the body is not at ease), WITH a distinctive group of symptoms AND a known cause.

What is pathology?

Study of diseases and how they affect the body + the structural and functional changes associated with a disease

What does pathology include?

Study of causes, mechanisms, signs and symptoms, and treatments and preventions

What is a pathologist?

A physician who studies and interprets changes caused by a disease

What do pathologists examine and why?

Cells, tissues, organs, and lab results, to find clues about the nature of a disease

How do we recognize disease?

Signs and symptoms

What are signs?

Signs are objective observable evidence (abnormal pulse, fever, sweating, etc)

What are symptoms?

Symptoms are subjective indications self reported by the patient (itchiness, dizziness, thirst, etc)

How are signs and symptoms ascertained?

Physical examination, interview with patient and family

Why is family history important for recognizing disease?

Provides insight into shared genetics and predisposing factors for disease

What is a syndrome?

An abnormal structure or function with a set of associated symptoms that occur together

What is a disorder?

A functional abnormality not necessarily linked to a specific cause or physical abnormality

Do disorders have signs and symptoms?

They can but don’t need to in order to be termed a disorder

Diagnosis meaning

Process of identifying a disease or disorder using information such as signs or symptoms

What is diagnosis used for?

To provide an explanation of a person’s health issues and develop a treatment plan

What is prognosis?

Likely course/outcome of a disease

What is prognosis used for?

To predict chance of recovery, chance for complications, and life expectancy (based on age, illness, and available treatments)

What is inspection?

Visual examination of the outside of the body, its posture, and movements (used to look for abnormalities or evidence of disease)

What is palpation and what is it used for (4 things)

Feeling the body with fingers or hands to examine size, texture, location consistency, and tenderness of an organ or body part

What is an auscultation, what does it examine (3 things), and what does it evaluate (5 things)

Listening to the heart, lungs, and intestines to evaluate the frequency, intensity, duration, number, and quality of sounds inside the body

What is percussion and what is it used to evaluate (4 things)

Tapping on the body with fingers, hands, or small instruments; used to evaluate size, consistency, borders of organs, and presence/absence of fluid

What are vital signs>

Vital signs are measures of physiological stats used to assess basic body functions (pulse, temperature, blood pressure, etc)

How do vital signs vary?

With age, sex, weight, and exercise tolerance/physical conditions

What do lab tests analyze?

Lab tests analyze the composition of blood, urine, stool, throat swabs, sputum, and other patient samples

What is a biopsy?

Surgical removal and analysis of tissue samples

What is a biopsy used for?

Useful for understanding changes at the cellular level, especially for tumours and masses

Electrocardiograph

Reads the heart’s electrical impulses

Radiography

Uses x-rays to visualize internal structures

CT (Computed Tomography)

Uses computers and x-rays to create 3D images of internal structures

MRI

Analyses tissue responses to a strong magnetic field and uses that to create images of internal structures

CT vs MRI similarities

Both non-invasive imaging techniques that give detailed views inside of the body

CT vs MRI differences

CT is faster and better for bones, lungs, and emergency situations, while MRI provides more detailed images of soft tissues like muscles, ligaments, and the brain

Ultrasound

Analyses how low frequency sound waves interact with tissues, used to create live moving images of internal organs and systems

Acute Disease

Disease with a sudden onset and a short duration (few days - few weeks)

Chronic Disease

DIsease with a slower onset and a long duration (months - years)

Terminal Disease

A disease that will always end in death

Deaths due to chronic diseases

7/10 in the us 6/10 worldwide

What does the leading cause of death differ by in countries?

Income level and economic development

Leading cause of death in wealthier countries?

Chronic diseases

Leading cause of death in low income countries?

Infectious diseases

What are the 4 predicted leading causes of death in 2030

Heart disease, stroke, COPD, and lower respiratory infections

What is remission?

A period where signs and symptoms may subsidize or disappear

Is a remission a cure?

No

How long does a remission last?

Days, months, or even years, no set timeframe

What is exacerbation?

Basically the opposite of remission; signs and symptoms grow more severe

Recur and relapse

Certain diseases are characterized by periods of remission and exacerbation. For example, leukemia is a common disease that is known to recur and relapse (relapse is the return of a disease weeks or months after its apparent cure)

Complication

A complication is a related disorder that develops in a person already suffering from a disease

Example of a complication?

Someone with a serious infectious disease can go into sepsis where the body’s extreme response to an infection damages its own tissues and organs

What is a sequela?

Aftermath of a particular disease

Examples of diseases and their sequelas?

Polio: paralysis
Diabetes: Diabetic nephropathy (kidney damage), diabetic neuropathy (nerve damage), and diabetic retinopathy (retina damage)

What is etiology

Cause of a disease (the why of a disease)

What is pathogenesis

The biological processes that result in the disease (the how of a disease)

What is it called when the cause of a disease is unknown?

Idiopathic

Do disease have single or multiple causes?

Some diseases seem to have a single cause, but many diseases have several causes