Nomenclature of diseases 2024 - Copy.pptx

Nomenclature & classification of disease Nomenclature of disease Classification of disease Learning outcomes 1. To understand the concept of disease 2. To be familiar with the standard conventions to name a disease 3. To describe how diseases are classified Nomenclature The System of names used in P...

Nomenclature & classification of disease Nomenclature of disease Classification of disease Learning outcomes 1. To understand the concept of disease 2. To be familiar with the standard conventions to name a disease 3. To describe how diseases are classified Nomenclature The System of names used in Pathology and Medicine - definition and concept Nomenclature of disease  Uniform nomenclature helps communication and enables accurate epidemiological studies  Many standard conventions are used to derive names of disease It is important to clarify the meaning of some of the common terms, prefixes and suffixes used in the nomenclature of diseases and their pathological features Disease  A condition in which the presence of an abnormality of the body causes a loss of normal health  The abnormality can be structural or functional  Due to the inability of an organism to adapt to a challenge  Clinical manifestation through signs and symptoms Nomenclature of Disease Primary and secondary: (used in two different ways) 1. To describe the causation of a disease Primary: disease without apparent cause (essential; idiopathic; spontaneous; cryptogenic) Secondary: disease is a complication or manifestation of some underlying lesion 2. To distinguish between the initial and subsequent stages of a disease (most commonly in cancer) Nomenclature of Disease Acute and chronic: To describe the dynamics of a disease  Acute: a rapid onset often but not always followed by a rapid resolution  Chronic: may follow an acute initial episode, and have a prolonged course lasting months or years Nomenclature of Disease Benign and malignant: To classify certain diseases according to their likely outcome  Benign tumours: remain localised to the tissue of origin and are very rarely fatal  Malignant tumours: invade and spread from their origin and are commonly fatal Prefixes Prefixes Meaning Example Ana- absence anaplasia Dys- disordered dysplasia Hyper- excess over normal HypoMeta- hypertension deficiency below normal hypotension change from one stage metaplasia to another Neonew neoplasia Suffixes Suffixes Meaning Example -itis, inflammatory process -oma, tumour -osis, abnormal increase -oid, bearing resemblance to rheumatoid disease -plasia disorder of growth -opathy abnormal state lacking specific characteristics appendicitis carcinoma atherosclerosis hyperplasia cardiomyopathy Eponymous names Disease or lesion is named after a person or place associated with it. Examples: − Graves’ disease: primary thyrotoxicosis − Crohn’s disease: a chronic inflammatory disease of the gut affecting most commonly the terminal ileum and causing narrow of the lumen General Classification of Disease Diagnosis uses the concept of disease classification to identify a disease in an individual patient Aims of disease classification are to: − Determine the best treatment − Estimate the prognosis − Ascertain the cause: so the disease can be prevented in the future The most widely used disease classifications are based on causes (aetiology) and underlying mechanism (pathogenesis) Genetic, acquired and congenital diseases Genetic diseases are due to abnormalities in the genome. Most are inherited, but ~15-20% occur due to new mutations in the affected individuals Acquired diseases are caused by environmental factors such as pollution In most diseases genetic and environmental factors interact Based on pathogenesis or disease mechanisms, most diseases can be assigned into the two classifications: Congenital and Acquired Congenital Disease Congenital Diseases: ~5% of birth in UK Initiated before or during birth, but some may not cause clinical manifestation until adult life Genetic: Inherited from parents or genetic mutation before birth Example: Down’s syndrome Non-genetic: External interference with normal embryonic and foetal development Example: deafness Genetic Disease Trisomy 21 (Down’s syndrome) Acquired diseases  Inflammatory  Haemodynamic  Growth disorders  Injury and disordered repair  Disordered immunity  Metabolic and degenerative disorders In lecture MCQ test Classification of diseases is commonly based on: a) The on-set of a disease b) The reversibility of a disease c) The name of the doctor who discovered it d) The mechanisms of a disease e) None of the above In lecture question and discussion Congenital Acquired Infectious Non-infectious 1. 2. 3. 4. Down’s syndrome Marfan syndrome Lung tuberculosis Huntington's disease 5. Parkinson's disease 6. Swine flu 7. Sickle-cell anaemia 8. Migraine 9. Meningitis