Differential diagnosis
915081
223642458
2008-07-05T01:16:53Z
59.167.212.218
/* Machine differential diagnosis */
{{Refimprove|date=June 2008}}{{nofootnotes}}{{expert-subject|Pathology|article}}In [[medicine]], '''differential diagnosis''' (sometimes abbreviated '''DDx''', '''ddx''', or '''ΔΔ''') is the systematic method healthcare providers use to identify the [[disease]] causing a patient's [[symptom]]s. In other words, part of [[diagnosis]] is attempting to narrow down the list of possible diagnoses until one emerges as the best. The term differential evolves from the word differences. The concept of differential diagnosis involves observing and discovering signs and symptoms, then progressively considering the most likely illnesses, then continuously narrowing down the possible diagnoses, eliminating one after another, until one is left with only one specific diagnosis for the patient's signs and symptoms.
Differential Diagnosis is the process whereby a given condition or circumstance, called the presenting problem or chief complaint, is examined in terms of underlying causal factors and concurrent phenomena as discerned by appropriate disciplinary perspectives and according to several theoretical paradigms or frames of reference, and compared to known categories of pathology or exceptionality. Differential diagnosis allows the physician to:
#more clearly understand the condition or circumstance
#assess reasonable prognosis
#plan treatment or intervention for the condition or circumstance
#enable the patient and the family to integrate the condition or circumstance into their lives, until the condition or circumstance may be ameliorated, if possible.
If the patient's condition does not improve, the diagnosis must be reassessed. The method of differential diagnosis was first suggested for use in the diagnosis of mental disorders by [[Emil Kraepelin]]. It is more systematic than the old-fashioned method of diagnosis by ''[[gestalt]]'' (impression).{{Fact|date=August 2007}}
The method of differential diagnosis is based on the idea that you begin by first considering the statistically more probable diagnoses. Medical students are taught the adage, "When you hear hoof beats, think horses, not zebras." It means that only after more probable diagnoses are ruled out do the somewhat less likely ones considered, and so forth. It used to be that doctors ordered only particular blood tests, but now the standard is a full blood chemistry profile which can speed up the process of diagnosis as well as uncover [[sub-clinical]] conditions. With the advent of better radiological studies like MRI and the wider use of nuclear medicine, it has become more likely that there will be unexpected findings that will be further studied, despite the fact that the findings will not be supported by further investigation. They are a valuable tool, but not infallible. It still often takes a physicians or medical team to track down either a more common illness with a rare presentation or a rare illness with symptoms suggestive of many other conditions. Sometimes a definitive diagnosis might take years.
Differential diagnosis also refers simply to a list of the most common causes of a given symptom, or a list of disorders similar to a given disorder; or such lists when they are annotated with advice on how to narrow down the list (the book ''French's differential diagnosis'' is an example).{{Fact|date=August 2007}} Thus, a differential diagnosis in this sense is medical information specially organized to aid in diagnosis.
The professional Merck Manual of medical diagnosis has 11 index entries describing the topic as differential diagnosis. The topic is mentioned within the body of 125 other separate articles on various medical conditions. reference below
==Machine differential diagnosis==
Machine differential diagnosis is the use of [[computer software]] to partly or fully make a differential diagnosis. It may be regarded as an [[application of artificial intelligence]].{{who}}
Typing in [[symptoms and signs]] in [[web search engines]] such as Google is one way of making a machine differential diagnosis.{{Fact|date=February 2008}} This, however, still requires medical skills to compare multiple results. A more specific search engine is [[eMedicine]], in which the entries are in addition graded on importance.
More advanced tools of differential diagnosis, e.g. [http://en.diagnosispro.com/ DiagnosisPro], are [[commercial software]]s.
However, these tools all still require advanced medical skills, in order to rate the symptoms and choose additional tests to deduce the probabilities of different diagnoses. Thus, non-professionals still need to see a [[health care provider]] in order to get a proper diagnosis.
{|class="wikitable"
|+Comparison
|-
! Tool !! External link !! Free !! Requires medical skills
|-
! Google
| [http://www.google.com/] || yes || yes
|-
! eMedicine
| [http://www.emedicine.com/diagnosis.shtml] || yes || yes
|-
! DiagnosisPro
| [http://en.diagnosispro.com/] || yes || yes
|-
! Dynamic Differential Diagnosis
| [http://www.quickddd.com/] || yes || yes
|-
|}
== Use in popular culture ==
The television show ''[[House (TV series)|House, M.D.]]'' focuses on a team of diagnosticians that use differential diagnosis to identify patients' varied afflictions.
== See also ==
*[[List of medical symptoms]]
*[[Medical sign]]
== Notes ==
{{reflist|2}}
==References==
* "differential diagnosis." Merriam-Webster's Medical Dictionary. Merriam-Webster, Inc. 12 Aug. 2007. [http://dictionary.reference.com/browse/differential%20diagnosis Dictionary.com].
* "differential diagnosis." The American Heritage Stedman's Medical Dictionary. Houghton Mifflin Company. 12 Aug. 2007. [http://dictionary.reference.com/browse/differential%20diagnosis Dictionary.com].
* "differential diagnosis." Google search of the online Merck Manual.http://www.merck.com/mmpe/search.html?qt=differential&qp=%2Bsite%3Awww%2Emerck%2Ecom+%2Burl%3A%2Fmmpe+%2Durl%3Aprint%2F+%2Durl%3Aindex%2F+%2Durl%3Aresources%2Fpronunciations+%2Durl%3Amultimedia%2F+%2Durl%3A%2Fmmpe%2Fau+%2Durl%3A%2Fmmpe%2Fag+%2Durl%3Alexicomp%2F&charset=utf8&la=en&start=0
[[Category:Medical terms]]
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[[el:Διαφορική διάγνωση]]
[[fr:Diagnostic différentiel]]
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