RIME or erythema multiforme major? Diagnostic classification before attributing clinical response to IVIg

This letter questions whether some IVIg-treated cases classified as erythema multiforme major may instead represent reactive infectious mucocutaneous eruption. Diagnostic heterogeneity, concomitant therapies and inconsistencies in the reported data limit attribution of clinical improvement specifically to IVIg, underscoring the need for explicit phenotypic classification before therapeutic inference.