A case report is a detailed report of the symptoms, signs, diagnosis, treatment, and follow-up of an individual patient. The most important aspect of a case report is that the case is unique, rare or interesting and that other medical professionals will learn something from it.
"Case reports and case series have their own role in the progress of medical science. They permit discovery of new diseases and unexpected effects (adverse or beneficial) as well as the study of mechanisms, and they play an important role in medical education. Case reports and series have a high sensitivity for detecting novelty and therefore remain one of the cornerstones of medical progress; they provide many new ideas in medicine. At the same time, good case reporting demands a clear focus to make explicit to the audience why a particular observation is important in the context of existing knowledge."
Vandenbroucke JP. . In Defense of Case Reports and Case Series. Annals of Internal Medicine. 2001;134(4):330-334.
The CARE guidelines (for CAse REports) were developed by an international group of experts to support an increase in the accuracy, transparency, and usefulness of case reports. The CARE guidelines for case reports help authors reduce risk of bias, increase transparency, and provide early signals of what works, for which patients, and under which circumstances.
The CARE guidelines help increase the completeness, accuracy, and transparency of published case reports.