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Subungual Hematoma with Feline Resemblance
Divya Sharma1, Brienne D Cressey2, Nathaniel J Jellinek1,3
1Department of Dermatology, The Warren Alpert Medical School at Brown University, Providence, Rhode Island, USA.
Skin Appendage Disorders
|April 8, 2020
Summary
A coincidental cat-shaped pigmented lesion on a thumbnail was noted in a patient with a cat tattoo. Dermoscopy is crucial for distinguishing such lesions from trauma.
Area of Science:
- Dermatology
- Dermatopathology
- Medical Coincidences
Background:
- Pigmented lesions on nails can be concerning and require accurate diagnosis.
- Differentiating benign findings from malignant melanoma is critical.
- The role of patient history and unique patient factors in diagnosis.
Observation:
- A 54-year-old woman presented with an incidental pigmented lesion on her right thumbnail.
- The lesion's shape coincidentally resembled a cat.
- The patient also had a cat tattoo, adding to the unusual presentation.
Findings:
- The case highlights unusual coincidences in dermatological presentations.
- Dermoscopy proved valuable in assessing the pigmented lesion.
- The importance of considering trauma-induced changes alongside neoplastic processes.
Implications:
- This case underscores the need for thorough dermatological evaluation, even with unusual presentations.
- Dermoscopy is an essential tool for the accurate diagnosis of nail-pigmented lesions.
- Awareness of coincidental findings can aid clinicians in avoiding diagnostic pitfalls.

