Comitance

Comitance is a term used in medicine to describe the co-occurrence of signs or symptoms that accompany a given disease or condition within the same patient. It refers to features that attend a primary illness and help characterize its clinical presentation. The word derives from Latin comitans, meaning “attending” or “accompanying.” While once more common in medical prose, comitance is now often described using terms such as accompanying features, symptom clusters, or the constellation of symptoms associated with a syndrome.

Comitance is not the same as comorbidity. Comorbidity refers to the presence of additional diseases or disorders that are not essential to the principal condition being considered. Comitance, in contrast, concerns signs and symptoms that are part of the same disease process, reflecting how the illness manifests across organ systems or in characteristic patterns.

In practice, comitance can help clinicians recognize typical symptom patterns of a disease. For example, a fever accompanied by rash, conjunctival injection, and malaise may be described as comitant features of a viral exanthem. However, comitance is not by itself a diagnostic criterion; it must be interpreted within the broader clinical context and alongside laboratory or imaging findings when available.

Limitations: The use and emphasis of comitance vary by medical specialty and region, and the term is less frequently used in modern practice, where more specific descriptors of symptom clusters or syndromic patterns are preferred.

See also: comorbidity, syndrome, symptom cluster, accompanying signs.