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Indurated Plaque with Bullae Formation on the Left Arm
Jennifer N Harb1, Thomas Hagele2, Paul Rodriguez-Waitkus3
1University of South Florida Morsani College of Medicine, Tampa, FL.
Skinmed
|December 22, 2018
Summary
A man presented with a worsening skin lesion. Absolute eosinophilia was noted, suggesting an underlying condition beyond typical infections.
Area of Science:
- Dermatology
- Hematology
- Immunology
Background:
- A 72-year-old male presented with a 4-month history of a progressive, tender, and pruritic lesion on his left arm.
- The lesion was characterized as an erythematous to violaceous, indurated, and sclerotic plaque with crusting and erosions.
Observation:
- The patient reported no history of trauma, recent travel, fever, chills, weight loss, or other constitutional symptoms.
- Previous treatments with cephalexin, prednisone, and doxycycline yielded no improvement.
Findings:
- Laboratory results were negative for antinuclear antibody and SCL70 antibody.
- A significant finding was an absolute eosinophilia of 1478/uL.
Implications:
- The presence of absolute eosinophilia in the context of a persistent, treatment-refractory skin lesion warrants further investigation.
- This case highlights the importance of considering hematologic or immunologic etiologies in complex dermatological presentations.
- Further diagnostic workup is needed to determine the cause of eosinophilia and the nature of the skin lesion.
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