Etiologi

Etiologi, often rendered as etiology in English, is the study of the causes and origins of diseases and other health conditions. It aims to identify the factors that initiate or contribute to disease onset, including biological, environmental, genetic, and behavioral elements.

In medicine, etiologi distinguishes the cause of a disease from its progression or mechanism. Etiology refers to the source or trigger, while pathogenesis describes the biological processes by which the cause leads to disease.

Etiological categories include infectious etiologies (pathogens such as bacteria, viruses, fungi, parasites); genetic etiologies (inherited mutations or chromosomal abnormalities); congenital etiologies (present at birth due to developmental factors); environmental etiologies (toxins, radiation, nutritional deficiencies); and lifestyle-related etiologies (smoking, alcohol use, poor diet). Many diseases are multifactorial, arising from interactions among several factors.

Clinical and public health relevance. Determining etiologies guides treatment choices, prevention strategies, and risk communication. Some conditions have well-established etiologies; others remain idiopathic or uncertain despite investigation.

Terminology and research approaches. An etiologic factor or etiologic agent is the direct cause of disease (for example, the bacterium that causes tuberculosis). Risk factors are variables that increase the likelihood of disease but are not direct causes. Etiologic research employs observational methods such as case-control and cohort studies, as well as experimental designs, to assess causal relationships and mechanisms.