Psoriasiform eruptions during Kawasaki disease (KD): A distinct phenotype

Abstract

Background: A psoriasis-like eruption develops in a subset of patients with Kawasaki disease (KD).

Objective: We sought to systematically compare KD-associated psoriasiform eruptions with classic psoriasis and the outcomes of KD in children with and without this rash.

Methods: This was a retrospective study of 11 KD cases with a psoriasiform eruption matched 1:2 by age, gender, and ethnicity with psoriasis-only and KD-only controls. Genotyping was performed in 10 cases for a deletion of 2 late cornified envelope (LCE) genes, LCE3C_LCE3B-del, associated with increased risk for pediatric-onset psoriasis.

Results: Similar to classic psoriasis, KD-associated eruptions were characterized clinically by well-demarcated, scaly pink plaques and histopathologically by intraepidermal neutrophils, suprabasilar keratin 16 expression, and increased Ki-67 expression. They showed less frequent diaper area involvement, more crust and serous exudate, and an enduring remission (91% vs 23% with confirmed resolution; P < .001). Frequency of LCE3C_LCE3B-del and major KD outcomes were similar between cases and controls.

Limitations: The study was limited by the small number of cases, treatment variation, and availability of skin biopsy specimens.

Conclusions: Although the overall clinical and histopathologic findings were similar to conventional psoriasis, this appears to be a distinct phenotype with significantly greater propensity for remission. No adverse effect on KD outcomes was noted.

Keywords: Kawasaki disease; Ki-67; LCE3C_LCE3B deletion; keratin 16; psoriasiform; psoriasis.