Case report

A case report is a detailed, descriptive account of the clinical presentation, diagnosis, treatment, and follow‑up of an individual patient (or a small group of patients) that presents an unusual, novel, or noteworthy medical condition or outcome. Unlike randomized controlled trials or cohort studies, which aim to generate generalizable evidence, case reports focus on singular observations and serve to highlight unique clinical phenomena, suggest hypotheses for further research, and contribute to medical education.

Contents

1. Definition
2. Historical background
3. Structure and typical components
4. Clinical and scientific significance
5. Limitations and criticisms
6. Ethical considerations
7. Publishing and peer review
8. See also
9. References

Definition

A case report documents:

• Patient demographics (age, sex, ethnicity, relevant medical history)
• Presenting complaint and duration of symptoms
• Physical examination findings
• Diagnostic investigations (laboratory, imaging, pathology)
• Therapeutic interventions (pharmacologic, surgical, supportive)
• Outcome and follow‑up data
• Discussion that places the case in context of existing literature, explains its significance, and may propose mechanisms or future research directions.

Historical background

Case reports have been part of medical literature since antiquity. Hippocrates (c. 460–370 BC) described individual patient observations, and the Corpus Hippocraticum includes early case histories. In the 19th century, physicians such as Sir William Osler popularized bedside teaching with detailed case narratives. The modern format solidified in the 20th century with journals like The Lancet and BMJ routinely publishing “case reports” sections.

Structure and typical components

1. Title – concise, often includes the diagnosis or key feature.
2. Abstract – brief summary (≈150 words) covering background, case description, and conclusion.
3. Introduction – contextualizes the rarity or relevance; outlines the purpose.
4. Case Presentation – systematic description as outlined in the definition.
5. Discussion – compares with previously reported cases, explores pathophysiology, clinical implications, and suggests hypotheses.
6. Conclusion – succinct statement of the main learning point(s).
7. Patient consent statement – affirmation that written informed consent was obtained.
8. References – citation of pertinent literature.
9. Figures/Tables – images (e.g., radiographs, histology) and data summaries, where appropriate.

Clinical and scientific significance

• Early detection of emerging diseases (e.g., initial reports of AIDS, COVID‑19).
• Identification of rare adverse drug reactions (e.g., thalidomide teratogenicity).
• Illustration of novel therapeutic approaches or procedural techniques.
• Educational tool for trainees to practice critical appraisal and differential diagnosis.
• Hypothesis generation for subsequent larger observational or experimental studies.

Limitations and criticisms

• Lack of generalizability – findings pertain to a single patient and cannot infer population‑level effects.
• Potential for bias – selection bias (authors choose striking cases) and reporting bias.
• Variable quality – inconsistency in methodological rigor, especially in literature searches and differential diagnosis documentation.
• Citation impact – many case reports receive few citations, raising questions about their influence.

Ethical considerations

• Informed consent is mandatory; patients (or legal guardians) must approve publication of identifiable data.
• Privacy – de‑identification of personal information in compliance with regulations such as HIPAA (USA) or GDPR (EU).
• Conflict of interest disclosure – especially when reporting novel therapies or devices.

Publishing and peer review

Several specialty‑specific journals focus exclusively on case reports (e.g., BMJ Case Reports, Journal of Medical Case Reports). Many general medical journals retain a “case reports” section, although some have reduced space due to impact‑factor considerations. Peer review criteria typically assess:

• Novelty or educational value
• Clarity and completeness of clinical information
• Adequate literature review
• Ethical compliance

See also

• Case series – collection of multiple case reports with common features.
• Observational study – broader epidemiological designs (cohort, case‑control).
• Clinical trial – experimental studies evaluating interventions.
• Medical literature – hierarchy of evidence (systematic reviews, RCTs, etc.).

References

1. Vandenbroucke JP. “Cases versus populations: should we have a different “gold standard” for clinical epidemiology?” J R Soc Med. 2003;96(12):571‑575.
2. Nissen R, et al. “The value of case reports in medical education.” Int J Med Educ. 2015;6:1‑5.
3. Goonetilleke C, et al. “The role of case reports in emerging disease surveillance.” Emerg Infect Dis. 2020;26(1):1‑3.
4. CARE Group. “CARE Guidelines: Consensus‑based Clinical Case Reporting Guideline Development.” J Med Internet Res. 2013;15(12):e265.
5. Huwiler M, et al. “Ethics of publishing patient case reports.” J Med Ethics. 2018;44(8):529‑533.