Inmedicine, describing adisease asacutedenotes that it is of recentonset; it occasionally denotes a shortduration. Thequantification of how much time constitutes "short" and "recent" varies by disease and by context, but the core denotation of "acute" is alwaysqualitatively in contrast with "chronic", which denotes long-lasting disease (for example, inacute leukaemia andchronic leukaemia).
In the context of themass noun "acute disease", it refers to the acute phase (that is, a short course) of any disease entity.[1][2] For example, in an article on ulcerativeenteritis inpoultry, the author says, "in acute disease there may be increasedmortality without any obvioussigns",[3] referring to the acute form or phase of ulcerative enteritis.
A mildstubbed toe is an acute injury. Similarly, manyacute upper respiratory infections andacute gastroenteritis cases in adults are mild and usually resolve within a few days or weeks.[citation needed]
The term "acute" is also included in the definition of several diseases, such assevere acute respiratory syndrome,acute leukaemia,acute myocardial infarction, andacute hepatitis. This is often to distinguish diseases from their chronic forms, such aschronic leukaemia, or to highlight the sudden onset of the disease, such as acute myocardial infarct.[2]
Related terms include:
| Term | Meaning |
|---|---|
| Peracute | Very acute or violent. Denotesfulminant, whereas "acute" only sometimes connotesfulminant. Peracute ("very") is not to be confused withpreacute ("before", the opposite ofpostacute). |
| Recurrent | "Happening again"—the concept is often one of multiple acute episodes.Relapse can mean the same asrecurrent, althoughrelapse is usually used to describe recurrence of chronic conditions that go intoremission and then recur. |
| Acute on chronic | An acute exacerbation of a chronic condition. It is applied to a variety of conditions, includingliver failure,[4][5]subdural hematoma,[6]renal failure,[7]respiratory failure,[8][9] andbronchitis. |
| Acute on chronic inflammation | A term sometimes used in pathology to describe a pattern ofinflammation which is a mixture of chronic and acute inflammation.[medical citation needed] It may be seen inasthma,[10]rheumatoid arthritis,[11] chronicpeptic ulcer,[11]chronic periodontitis,[11]tuberculosis,[11]tonsillitis and other conditions. |
| Subacute | A vaguely defined state that is clearly not acute, but rather between acute and chronic,[1][2] for examplesubacute endocarditis, orsubacute sclerosing panencephalitis. |
| Chronic | A long-term condition.[1][2] |
Acute care is the early and specialist management of adult patients who have a wide range of medical conditions requiring urgent oremergency care usually within 48 hours of admission or referral from other specialties.[2]
Acute hospitals are those intended for short-term medical and/or surgical treatment and care which is amedical speciality ofacute medicine, as oftenprimary care is not positioned to assume this role.[12]