The structure:

My simple and short approach to writing abstract for case reports is to organize the abstract of case report in three sub-sections, consisting of 150-200 words:

Introduction, Case Presentation, and Take-away Lesson.

The approach:

Introduction:
In 1-2 sentences refer to the topic in general and its importance. That’s all!

Case Presentation:
in 2-3 sentences present the case in brief, the summary of the main signs, symptoms, and laboratory and imaging findings. Then, the author is required to write 1-2 sentences about any treatment measures, follow ups (if applicable), and the final outcome of the case.

Take-away Lesson:
Here, at the end of abstract, provide any relevant practical conclusion (for health or treatment policy makers), in 1-2 sentences.