Clinical case reports correspond to articles that have the lowest level of evidence within different research trials. However, not only are they common and significant in the medical field, but they have often been the basis the generation of research. The purpose of their publication can be scientific or educational. In general terms, the discovery of new diseases, the presentation of rare diseases, unusual forms of common diseases, the complications of a common treatment, or the effect (beneficial or adverse) of a treatment, among other things, are narrated in these documents. Clinical case reports continue to be one of the most important sources of knowledge. The advent of a standardized guideline for the creation of this type of reports allows homogenizing the form and content of the cases intended to be described in the near future and, furthermore, will enable authors to have a reference when preparing this type of publications. Case reports are valuable resources of new and unusual information that can encourage and serve to conduct future research studies with a higher level of evidence.