1) They are sometimes clinically hard to distinguish from EVHC, and both are associated with keratin 17 gene mutations and type 2 pachyonychia congenita.
4) Although EVHC have been reported in association with hypohidrotic ectodermal dysplasia, this patient does not have any of the dysmorphic features associated with this syndrome.
Patients with pachyonychia congenita (type 2) also may have EVHC as part of their presentation, but this patient does not have nail dystrophy, focal palmoplantar tar keratoderma, follicular keratoses, or multiple steatocysts, which also are features of this condition.
A 2012 review of 220 cases of EVHC found that topical retinoic acid, incision/excision, C[O.
Forty years have passed since EVHC was identified as a distinct disease entity.