Introduction to Pathophysiology, Stress and
Adaptation
Sections:
• Pathophysiology Terms
• Etiology
• Framework for Pathophysiology
• Concepts Related to Stress
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Pathophysiology
Pathophysiology = The study of
functional changes associated with a
particular disease.
Pathology = Study of disease
Etiology = Cause or reasons for
phenomena
Clinical manifestations – How the
disease presents
Pathogenesis = Development or
evolution of disease, from initial
stimulus to ultimate expression of
manifestations of the disease – How the
disease progresses.
- Occurs in stages
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Overview of Health and Illness
Characteristics of Health and Illness
– Health– absence of disease or functional changes that
result with disease
– Disease – Impaired function
– Disorder – Describes a disruption of physiologic or
psychologic function
– Illness – In healthcare is used to describe the individual
experience that a person has with disease
– Syndrome – Refers to a group of signs and symptoms
from a disease state
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Framework for Pathophysiology
Topics in pathophysiology
– Etiology - Study of causes
or reasons for
phenomena—Why
someone gets sick.
– Risk Factors – A factor
that when present
increases the likelihood of
disease.
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Etiologic Classes of Disease
Other Etiological Terms
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• Idiopathic- cause is unknown
• Iatrogenic- Cause results unintentionally from medical treatment,
diagnostic procedure or error
• Inherited – ie., genetic
• Congenital – ie., born with it
• Metabolic – screwed up chem reactions
• Degenerative – tissues/organs progressively degrade over time
• Neoplastic – abnormal growth of cells
• Immunologic - caused by dysfunction of immune system
• Infectious – caused by organisms such as bacteria, viruses, fungi
etc.
• Physical Agent-Induced – like altitude, wetness, radiation, lightning ,
fire, etc
• Psychogenic – mental or emotional connection
Framework for Pathophysiology
Topics in pathophysiology
– Clinical manifestations – How the disease presents
• Signs: objective or observed manifestation of disease by the
person conducting the exam
– Examples: Fever, change in heart or respiratory rate
• Symptoms: subjective feeling of abnormality in the body by
the affected individual but is not observed by the examining
the individual
– Examples: Pain, nausea, numbness
• Syndrome: A collection of clinical signs, symptoms and data
– Treatment implications - Understanding the particular
disorder/disease/illness may determine which
treatments could be helpful—Not the main focus of
this class….
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More Important Terms
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•
•
•
•
Acute – sudden onset
Chronic – long-term
Exacerbation – gets worse
Remission – decrease in severity
Mortality – death
• Morbidity – state of disease, disorder, injury, or
disability
• Evidence based practice – peer reviewed, science
informed
• Differential diagnosis
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Differential Diagnosis
• Systematic technique for identifying an “unknown”
– i.e., attempt to narrow down possible diagnoses
– Some disease is easily defined … one cause
– Many are a set of signs/symptoms … may have 1 cause or many à
syndromes
• Make a list of symptoms
• Make a list of possible diagnoses à always start with most obvious or most
simple explanation
• Run tests to gradually “rule out” potential diagnoses
• Why it’s important in medicine
– Better understand potential and assess prognosis
– Deal immediately with life-threatening things
– Plan treatment/intervention
– Facilitate patient/family understanding/compliance
• If treatment doesn’t improve condition … then differential diagnosis process
revisited
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Question
Which of the following is an example of the clinical
manifestation known as a sign?
A.
B.
C.
D.
Nausea
Bruise
Headache
Loss of appetite
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3
Question
Which of the following is an example of the clinical
manifestation known as a sign?
A.
B.
C.
D.
Nausea
Bruise
Headache
Loss of appetite
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Question
You are caring for patients with syndromes. Which
of the following defines this term?
A. Situation that is impairing functional ability
B. Something that puts a patient at greater risk of
developing a disease
C. Disruption of psychological function
D. Group of signs and symptoms that emerge from
a disease state
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Question
You are caring for patients with syndromes. Which
of the following defines this term?
A. Situation that is impairing functional ability
B. Something that puts a patient at greater risk of
developing a disease
C. Disruption of psychological function
D. Group of signs and symptoms that emerge from
a disease state
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Homeostasis vs Allostasis
Homeostasis- Remaining stable while staying
the same-balance
– An ideal “set point” despite alterations within
the body
– A state of equilibrium
Allostasis- Ability to successfully adapt to
challenges
• Intricate regulatory processes
orchestrated by the brain
• A dynamic process that maintains or reestablishes homeostasis in light of
environmental and lifestyle changes
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Adaptation, Coping and Illness
Allostatic overload: inadequate adaptation
mechanisms or excessive allostatic load;
results in inability to maintain homeostasis
– Leads to various illnesses and disorders, both
physical and emotional
– Chemical mediators from the stress response
contribute to various illnesses: cortisol,
catecholamines, cytokines
Pathophysiology
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The Physiology of Stress
A series of neural and chemical reactions meant
for physical survival
By beginning to understand the physiology of stress, then
you can begin to use this knowledge to augment your
own health and well-being in terms of techniques like
mental imagery, biofeedback, diaphragmatic
breathing, etc.
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5
Systems Affected by Stress
vImmune system
vCardiovascular system
vGastrointestinal system
vMuscles
vSkin
vReproductive
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Diseases Related to Stress
•
•
•
•
•
•
•
•
•
•
Hypertension
Stroke
Coronary Heart Disease
Ulcers
Migraine Headaches
Tension Headaches
Allergies
Rheumatoid Arthritis
Backache
TMJ Syndrome
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Adaptation, Coping and Illness
Individual stress responses: change with time and
circumstances
Effects of stress response influenced by:
– Genetics
– Socioeconomic status
– Prior susceptibilities
– Preexisting health status
– Allostatic state
– Ability to manage stress
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