Subcutaneous schwannoma, histopathology, S-100

Diagnosis: Subcutaneous schwannoma, histopathology, S-100

Case submitted by dermRounds Dermatology Network to the dermRounds community.

Clinical Presentation

Clinical photograph(s) submitted for peer review and discussion.

Clinical History

Submitted by dermRounds Dermatology Network. Originally posted June 27, 2008.

Treatment

See case discussion.

Differential Diagnosis

• Erythema multiforme • Toxic epidermal necrolysis • Staphylococcal scalded skin syndrome • Drug reaction with eosinophilia and systemic symptoms (DRESS) • Paraneoplastic pemphigus • Acute generalized exanthematous pustulosis (AGEP) • Bullous pemphigoid

Key Learnings

• SJS/TEN are a spectrum: SJS (30%) • Drug-induced in ~80% of cases — most common culprits: allopurinol, sulfonamides, carbamazepine, phenytoin, lamotrigine, nevirapine, NSAIDs (oxicam) • HLA-B*5801 screening before allopurinol (especially in Southeast Asian, Korean, African American populations) • HLA-B*1502 screening before carbamazepine (Han Chinese, Southeast Asian) • SCORTEN score predicts mortality • Mucosal involvement (≥2 sites) is characteristic — oral, ocular, genital • Ocular complications can be devastating — ophthalmology consultation essential • Treatment is largely supportive — transfer to burn unit for severe cases • Cyclosporine may reduce progression if started early (emerging evidence)

Tags: subcutaneous, schwannoma, histopathology, 100, dermrounds dermatology network