The term 'symptom' (from the
Greek '' meaning 'chance', 'mishap' or 'casualty', itself derived from ''συμπιπτω'' meaning 'to fall upon' or 'to happen to') has two similar meanings in the context of physical and
mental health:
★ Strictly, a symptom is a sensation or change in health function experienced by a patient. Thus, symptoms may be loosely classified as
strong,
mild or
weak. In this, medically correct, sense of the word, it is a ''
subjective'' report, as opposed to a sign, which is ''
objective'' evidence of the presence of a
disease or disorder. Examples of ''symptoms'' are
fatigue/
tiredness,
pain, or
nausea. In contrast,
elevated blood pressure, or abnormal appearance of the
retina, would be a
medical sign indicating the nature of the disease.
★ A symptom may loosely be said to be a physical condition which indicates a particular illness or disorder (e.g. Longman, 1995). An example of a symptom in this sense of the word would be a
rash. However, correctly speaking, this is known as a
sign, as would any indication detectable by a person other than the sufferer without verbal information from the
patient.
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 only a very limited 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. Clearly then, the same feature may be noticed by both doctor and patient, and so is at once both a sign and a symptom. The distinction is as simple as this, and therefore it may be nonsensical to argue whether a particular feature is a sign or a symptom. It 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 (unless he is the patient!). 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.
See also
★
Diagnosis
★
Disease
★
★
List of diseases
★
★
List of disorders
★
List of medical symptoms
★
Pathogenesis
★
Symptomatic treatment
Reference
★ ''Longman Dictionary of Contemporary English'' (1995). Third edition.
External links
★
Medical Decision Support Computing
★
Medical symptom report creator
★
Medical Symptoms Database
★
Online Medical Symptom Checker
★
Symptomat Online Medical Symptom Checker
★
MSO Online Medical Symptom Checker