AbstractSeveral studies have suggested that mutation of the interleukin 36 receptor antagonist gene (IL36RN) is related to generalized pustular psoriasis (GPP), and the presence of IL36RN mutation may affect the clinical manifestations and treatment responses. However, genetic testing is not routinely available in clinical practice for the diagnosis of GPP. Previously, GPP patients with acrodermatitis continua of Hallopeau (ACH) were found to have a high percentage of carrying IL36RN mutation. In this study, we reported six patients with pustular psoriasis presenting as diffuse palmoplantar erythema with keratoderma among 60 patients who carried IL36RN mutation. ACH was present in five patients and five patients had acute flare of GPP. This unique presentation may serve as a predictor for IL36RN mutation in patients with pustular psoriasis, similar to ACH.