|
A symptom is a manifestation of a disease, indicating the nature of the disease, which is noticed by the patient. This may be contrasted to signs which are observed by a medical practitioner. A symptom is subjective,http://www.uwo.ca/pathol/glossary.html#S observed by the patient,http://www.emedicine.com/asp/dictionary.asp?keyword=symptom and not measured.Devroede G (1992). "Constipation--a sign of a disease to be treated surgically, or a symptom to be deciphered as nonverbal communication?". J. Clin. Gastroenterol. 15 (3): 189–91. PMID 1479160.
Contents |
A symptom may loosely be said to be a physical condition which indicates a particular illness or disorder.Longman Dictionary of Contemporary English (1995). Third edition.
A given phenomenon, such as a rash, can be both a symptom and a sign-- it is a symptom when observed by the patient, and a sign when observed by the phycisian, as explained in below.
Some symptoms, such as nausea, occur in a wide range of disease processes, whereas other symptoms are fairly specific for a narrow range of illnesses. For example, a sudden loss of sight in one eye has a significantly smaller number of possible causes.
Some symptoms can be misleading to the patient or the medical practitioner caring for them. For example, inflammation of the gallbladder often gives rise to pain in the right shoulder, which may understandably lead the patient to attribute the pain to a non-abdominal cause such as muscle strain, rather than the real cause.
The terms chief complaint, presenting symptom, or presenting complaint is used to describe the initial concern which brings a patient to a doctor. The symptom that leads to a diagnosis is called a cardinal symptom.
A symptom can more simply be defined as any feature which is noticed by the patient. A sign is noticed by the doctor or others. It is not necessarily the nature of the sign or symptom which defines it, but who observes it.
The same feature may be noticed by both doctor and patient, and so is at once both a sign and a symptom. A sign or a symptom may be one, the other, or both, depending on the observer(s).
Some features, such as pain, can only be symptoms. A doctor cannot feel a patient\'s pain. Others can only be signs, such as a blood cell count measured by a doctor or a laboratory.
In engineering, symptom may be used to refer to an undesired effect occurring in a system. To eliminate the effect, a root cause analysis is performed which traces the symptom to its cause and again through the cause\'s cause and so on until the subsystem is identified that can be changed to eliminate the symptom.
| This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (December 2007) |
This article is licensed under the GNU Free Documentation License. It uses material from Wikipedia