Endotype

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An endotype is a subtype of a health condition, which is defined by a distinct functional or pathobiological mechanism. [1] This is distinct from a phenotype, which is any observable characteristic or trait of a disease, such as development, biochemical or physiological properties without any implication of a mechanism. It is envisaged that patients with a specific endotype present themselves within phenotypic clusters of diseases.

Contents

One example is asthma, which is considered to be a syndrome, consisting of a series of endotypes. [2] This is related to the concept of disease entity.

Disease entity

The main concept in nosology is the disease entity. Normally there are two ways to define a disease entity: Manifestational criteria and causal criteria. [3]

Following Fred Gifford, [4] these criteria lead one to view any disease entity in three different forms: [5]

Following again F. Gifford, in fact each of the previous definitions can include the aetiology or can be aetiologically agnostic. Other authors simply continue with the classification of Whitbeck, leaving just three kinds of definition (clinical, pathological and aetiological). [6]

It is important to note that a real-world definition is normally a hybrid between these above kinds, and an endotype should use all three of the descriptors - including aetiology - to ensure specificity.

See also

Notes

  1. Russell C, Baillie JK (April 2017). "Treatable traits and therapeutic targets: Goals for systems biology in infectious disease". Current Opinion in Systems Biology. 004 (3): 139–45. doi: 10.1016/j.coisb.2017.04.003 . PMC   7185428 . PMID   32363252.
  2. Lötvall J, Akdis CA, Bacharier LB, Bjermer L, Casale TB, Custovic A, Lemanske RF, Wardlaw AJ, Wenzel SE, Greenberger PA (February 2011). "Asthma endotypes: a new approach to classification of disease entities within the asthma syndrome". The Journal of Allergy and Clinical Immunology. 127 (2): 355–60. doi:10.1016/j.jaci.2010.11.037. PMID   21281866.
  3. Victor J. Schoenbach, Phenomenon of disease, 2000
  4. Hucklenbroich P (December 2014). ""Disease entity" as the key theoretical concept of medicine". The Journal of Medicine and Philosophy. 39 (6): 609–33. doi: 10.1093/jmp/jhu040 . PMID   25344894.
  5. Philosophy of medicine. Gifford, Fred (Professor) (1st ed.). Amsterdam. 6 September 2011. ISBN   978-0-444-51787-6. OCLC   744637035.{{cite book}}: CS1 maint: others (link)
  6. Whitbeck, Caroline (1977). "Causation in Medicine: The Disease Entity Model". Philosophy of Science. 44 (4): 619–637. doi:10.1086/288771. ISSN   0031-8248. JSTOR   186942.

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