Nature and causation of disease
Disease or dis - ease

Aetiology
endogenous - arising within the organism
exogenous - originating outside the organism

Genetic
Congenital disorders
Deficiency
Teratogenic
Infections
Rhesus incompatibility

Exogenous disease

Mechanical causes
temperature
radiation
atmospheric pressure
electricity

Chemical causes
Effects may be local or systemic
Acids and alkalines
Heavy metals
Air pollution
Water/food pollution
Special areas of body, e.g. eye, mouth
Medicines as poisons
Intoxication
Auto-intoxication, eg renal failure

Malnutrition
Shortage, surplus
unbalanced diet
combinations of these factors

Biological causes
An infectious disease meets Koch`s postulates
Diseases caused by pathogenic micro-organisms
bacteria
fungi
virus
protozoa
mycoplasm
metazoans
prions

Vascular causes
Macrovascular, Microvascular
Atherosclerosis, Arteriosclerosis
Arteriolosclerosis
Ischaemic heart disease
Cerebrovascular disease

Allergy and hypersensivity
Antigen - antibody reaction
Allergens may take many forms
Asthma, Local allergy
Systemic allergy

Autoimmunity
A specific body tissue is attacked by the immune system
Diabetes mellitus type 1
Myasthenia gravis, Rheumatoid disease

Neoplasm
An abnormal (new) mass of tissue
A tumour
Cancer is a malignant neoplasm
Tumours may be benign

Causes of cancer;
ionising radiation
carcinogenic chemicals
oncogenic viruses
oncogenes

Degenerative causes
Wear and tear
Accumulation of unwanted material

Psychiatric problems
Functional
Organic
May be psychotic or neurotic
Psychosomatic disorders.
Interaction of factors in terms of the whole person.

Psychosomatic
Mind affects the body

Iatrogenic
Caused by medical treatments

Idiopathic
Primary disease

Terms
Aetiology
Aneurysm
Arteriosclerosis
Atherosclorosis
Carcinogenic
Delusion
Embolism
Haematemesis
Haematuria
Hallucination
Iatrogenic
Illusion
Inflammation
Infarction
Ischaemia
Multifactorial aetiology
Necrosis
Pathogenic micro-organism
Pathogenesis
Sclerosis
Shock
Thrombosis

Identify aetiological factors for the following diseases.
Pneumonia
Haemophilia
Blue-green colour blindness
Sickle cell anaemia
Pernicious anaemia
Down’s syndrome
Chronic obstructive airway disease
Malignant melanoma
Obesity
Amphetamine psychosis
Intermittent Claudication
Cerebral thrombosis
Myocardial infarction
Athlete’s foot (tinea pedus)
Amoebic dysentery