What is pathophysiology?
• Pathophysiology is the study of what happens when
normal anatomy and physiology go wrong.
• It is the “why” that unlocks all the mysteries of the human
body.
• Pathophysiology is the basis for understanding the
intricate world of the human body, its response to disease,
and the rationale for treatment.
Introduction to pathophysiology
Why is it so important to understand pathophysiology?
Understanding why patients look the way they do when they have a
certain disease?
Why this medicine works in this disease?
Why complications sometimes transpire?
Pathophysiology provides the rationale for evidence-based medicine.
Can bring meaning and understanding to the world of health and
disease.
Introduction to pathophysiology
For each disease we should know:
Etiology
Signs
pathophysiology
Investigations
Symptoms
Treatment
Introduction to pathophysiology
prognosis
Diseases can be classified according to the aetiology in
several ways.
• Hereditary: meaning it is transmitted before birth e.g., sickle cell
disease.
• Genetic diseases are caused by abnormalities in the individual’s
genes (e.g., down syndrome).
• Inflammatory diseases are those that trigger the inflammatory
response. e.g., bronchitis.
• Traumatic: are caused by trauma e.g. fracture caused by car
accident.
• Degenerative diseases include conditions that cause parts of the
body to deteriorate (e.g., arthritis).
• Metabolic diseases: Conditions that affect metabolism (e.g.,
diabetes mellitus).
Introduction to pathophysiology
• Neoplastic diseases: are caused by abnormal or uncontrolled
cellular growth, which can lead to benign and malignant tumours
• Idiopathic: the cause is unknown.
• A syndrome comprises a group of signs and symptoms that occur
together. E.g. Down’s Syndrome.
• Predisposing factors are tendencies that put an individual at risk
for developing certain diseases. E.g., dust is a predisposing factor
for bronchial asthma.
• Give more examples?
• Why do we need to know the aetiology and predisposing factors
for a disease?
For disease prevention
For disease treatment
Introduction to pathophysiology
The onset of the disease
• Can be classified into:
1. Sudden onset e.g., fracture leg in trauma
2. Acute onset e.g., infections
3. Gradual, or insidious onset may be associated with only
vague signals e.g., HTN, DM, cancer
Introduction to pathophysiology
Classifications of the disease according to The duration
• Can be classified into:
1. Acute disease: disease of a short term, occurring and
resolving quickly e.g., Gastroenteritis.
2. Chronic disease: When the disease does not resolve after a
short period, it may move into a chronic state. E.g., Diabetes
mellitus and bronchial asthma .
3. Acute on top of chronic disease: e.g., acute asthma attack.
Introduction to pathophysiology
How can we make the diagnosis?
Diagnosis of the disease depends on:
1. History taking
2. Physical examination.
3. Investigations (lab, radio or invasive like a biopsy).
Introduction to pathophysiology
Signs VS Symptoms
 Signs are objective manifestations
detected by an observer during a
physical examination e.g.,
abnormal heart sounds
 Symptoms what the patient
describes but is not visible to the
healthcare practitioner e.g.,
Fatigue , abdominal pains
Introduction to pathophysiology
Treatment
Treatment refers to strategies used to manage or cure a disease.
Treatment may be:
1. Specific treatment to the cause of the disease e.g.,
antibiotics in acute bronchitis.
2. Symptomatic treatment that used to alleviate the patient’s
symptoms., antipyretics for fever.
3. Preventive treatment: used for disease prevention. E.g.,
COVID 19 vaccination.
Introduction to pathophysiology
• Prognosis refers to an individual’s likelihood of making a full
recovery or regaining normal functioning.
• Complications are new problems that arise because of a
disease. For example, renal failure can be a complication of
uncontrolled hypertension or diabetes mellitus.
Introduction to pathophysiology
Each team choose any disease and
comment on:
Disease aetiology
Onset (sudden, acute, gradual)
Duration of the disease (Acute, chronic)
Symptoms
Signs
Possible complications
Investigations
Treatment
Prognosis (good/bad)
Introduction to pathophysiology