Clinical symptom

A symptom (from Greek σύμπτωμα, "accident, misfortune, that which befalls", from συμπίπτω, "I befall", from συν- "together, with" and πίπτω, "I fall") is a departure from normal function or feeling which is noticed by a patient, reflecting the presence of an unusual state, or of a disease. A symptom is subjective, observed by the patient, and cannot be measured directly, whereas a sign is objectively observable by others. For example, paresthesia is a symptom (only the person experiencing it can directly observe their own tingling feeling), whereas erythema is a sign (anyone can confirm that the skin is redder than usual). Symptoms and signs are often nonspecific, but often combinations of them are at least suggestive of certain diagnoses, helping to narrow down what may be wrong. In other cases they are specific even to the point of being pathognomonic.

The term is sometimes also applied to physiological states outside the context of disease, as for example when referring to "symptoms of pregnancy".

Symptoms may be briefly acute or a more prolonged but acute or chronic, relapsing or remitting. Asymptomatic conditions also exist (e.g. subclinical infections and silent diseases like sometimes, high blood pressure).

Constitutional or general symptoms are those related to the systemic effects of a disease (e.g., fever, malaise, anorexia, and weight loss). They affect the entire body rather than a specific organ or location.

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