- Human pathology

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Wednesday 16 July 2003

human disease


Definition: A disease is a particular abnormal condition, a disorder of a structure or function, that affects part or all of an organism .

The causal study of disease is called pathology. Disease is often construed as a medical condition associated with specific symptoms and signs.

Diseases may be caused by external factors such as pathogens, or it may be caused by internal dysfunctions, such as autoimmune diseases. The study of the causes of diseases is etiology.

A disease differs from a syndrome , which is a collection of signs or symptoms that occur together. However, for historical reasons, many conditions have been identified, yet continue to be referred to as "syndromes". Furthermore, numerous conditions of unknown etiology are referred to as "diseases" in many contexts.


- Diseases
- Disease localizations

- Group of diseases

Etiological classification

- chromosomal diseases
- genetic diseases
- infectious diseases (infections / infection)
- dysimmunity
- environmental diseases
- nutritional diseases

Physiopathological classification

- developmental anomalies (malformations )
- metabolic diseases
- inflammatory diseases
- tumoral diseases (Tumors )


- systemic diseases
- localized diseases (diseases of a structure)

See also

- classification of diseases ( nosology )
- causes of diseases ( etiology )
- communicable diseases ( infectious diseases )
- non-communicable diseases (non-communicable diseases )




- Wright A, Charlesworth B, Rudan I, Carothers A, Campbell H. A polygenic basis for late-onset disease. Trends Genet. 2003 Feb;19(2):97-106. PMID: 12547519

- Reich DE, Lander ES. On the allelic spectrum of human disease. Trends Genet. 2001 Sep;17(9):502-10. PMID: 11525833