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Pemetrexed-Induced Pseudocellulitis Reaction With Eosinophilic Infiltrate on Skin Biopsy
Elisabeth H Tracey1, Badri Modi, Robert G Micheletti
1*Perelman School of Medicine, University of Pennsylvania; Departments of †Dermatology; and ‡Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
Abstract:
Peripheral edema with painful erythema is an increasingly recognized but poorly understood cutaneous adverse reaction to the antifolate agent pemetrexed. It is frequently misdiagnosed as cellulitis, and when it occurs, it is often dose-limiting. The authors report the case of a patient with preexisting lower extremity edema who developed extensive painful, bilateral erythema 5 days after administration of pemetrexed. An eosinophil-rich dermal inflammatory infiltrate was noted histologically. The authors review previously reported cases of pemetrexed-induced pseudocellulitis and discuss possible pathophysiology.
Insights
Pemetrexed, an antifolate drug, can cause painful skin redness and swelling, often mistaken for cellulitis. This reaction can limit treatment dosage and requires careful diagnosis.
Area of Science:
- Oncology
- Dermatology
- Pharmacology
Background:
- Pemetrexed is an antifolate chemotherapy agent.
- Cutaneous adverse reactions to pemetrexed are increasingly recognized.
- Peripheral edema with painful erythema is a poorly understood side effect.
Observation:
- A patient with pre-existing lower extremity edema developed erythema and edema post-pemetrexed administration.
- The reaction occurred 5 days after pemetrexed treatment.
- The symptoms were bilateral, extensive, and painful.
Findings:
- Histological examination revealed an eosinophil-rich dermal inflammatory infiltrate.
- The condition is frequently misdiagnosed as cellulitis.
- Pemetrexed-induced pseudocellulitis can be dose-limiting.
Implications:
- Accurate diagnosis of pemetrexed-induced pseudocellulitis is crucial for patient management.
- Understanding the pathophysiology may lead to better prevention or treatment strategies.
- This adverse reaction can impact chemotherapy treatment plans.
