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Published on: October 12, 2012
Granuloma annulare masquerading as erythema multiforme
Kenneth Beer1, Michael S Beer, Danielle Appelbaum
1kenbeer@aol.com
Abstract:
Erythema multiforme (EM) is a serious cutaneous and/ or mucocutaneous disorder that typically develops within 10-14 days of exposure to an offending medication or infection and resolves within 4 weeks. Common offending agents include antibiotics, anticonvulsants, nonsteroidal anti-inflammatory medications, and various viral, fungal, and bacterial infections. Herpes simplex virus is a common cause of recurrent EM. Although this condition may be relatively benign in its minor form, EM major can lead to serious complications and even death. As such, it is imperative to find and remove the etiologic agents in patients with EM. We present a case that presented clinically as erythema multiforme, with arcuate, indurated, erythematous plaques on the volar aspect of her hands. Histopathology, however, demonstrated the lesions to be granuloma annulare. The medications in our patient were essential and alterations to her medical regimen would have been problematic. As such, this case demonstrates the importance of histopathologic examination in patients with lesions suspected to be EM.
Insights
Erythema multiforme (EM) can mimic other skin conditions. This case highlights the critical role of histopathology in diagnosing EM, especially when essential medications are involved.
Area of Science:
- Dermatology
- Pathology
Background:
- Erythema multiforme (EM) is an acute, immune-mediated mucocutaneous condition.
- It is typically triggered by infections or medications, presenting with characteristic skin lesions.
- Severe cases (EM major) can lead to significant morbidity and mortality.
Observation:
- A patient presented with clinical signs suggestive of EM, including arcuate, indurated, erythematous plaques on the hands.
- The patient was on essential medications, making their removal a problematic consideration.
Findings:
- Histopathological examination revealed the lesions were consistent with granuloma annulare, not EM.
- This finding underscores the potential for clinical misdiagnosis in EM-like presentations.
Implications:
- Histopathological examination is crucial for accurate diagnosis of suspected EM.
- It guides appropriate management, especially when potential triggers are essential medications.
- This case emphasizes avoiding premature discontinuation of necessary therapies based solely on clinical suspicion.
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