Subcorneal pustular dermatosis in a patient with Crohn's disease

Pustular Rash in Crohn's Patient on Ustekinumab Raises Concern for Drug-Induced Paradoxical Psoriasis

We report the case of a 51-year-old male with Crohn's disease (CD) who developed a reproducible pustular rash after ustekinumab (UST) administration. The patient first presented with a pustular rash on his hands, body, extremities, and scalp starting 5 weeks after his initial weight-based UST induction. The rash resolved spontaneously, then recurred 4 weeks after his first subcutaneous maintenance dose of UST 90 mg. Biopsy of the affected area demonstrated subcorneal pustular dermatosis (SPD). UST was discontinued and the rash resolved. Unfortunately, the patient experienced clinical recurrence of CD, and given prior failure of multiple CD medications, UST was restarted with premedication. Two weeks after UST re-induction, the rash recurred, though less severe. Given improvement in CD symptoms, UST was continued and the rash managed with topical corticosteroids. This is the first case of drug-induced SPD associated with UST. One case report has previously described de novo pustular psoriasis associated with UST in a patient with CD and enteropathic arthritis. Notably, SPD and pustular psoriasis can be histologically indistinguishable. The development of a paradoxical psoriasiform rash is thought to be one of the few dose and duration dependent side effects of TNF-antagonist therapy but has not previously been established as a side effect of UST. This case demonstrates a new potential side effect of UST.

Subcorneal pustular dermatosis: Comprehensive review and report of a case presenting during pregnancy

Subcorneal pustular dermatosis (SPD), also known as Sneddon-Wilkinson disease, is a rare, relapsing, sterile pustular eruption of unknown etiology that develops most commonly in middle-aged or mature women. This article reviews the presentation, associations, and management of the condition and highlights advances in pathophysiology. Onset of SPD during pregnancy has not been reported. Herein, we report a case of SPD that developed during pregnancy. The patient was treated with dapsone without complications for her or the fetus. An association between T helper (Th) 17 and Th2 environments in the development of SPD has been advocated. Pregnancy is characterized by a predominance of Th2 responses and increased interleukin-17 levels and thus may favor the development of the condition.

First presentation of Sneddon-Wilkinson disease with unexpected immunoglobulin A gammopathy: A case report and review of the literature

We present a case of Sneddon-Wilkinson disease in a 52-year-old female at her first presentation to dermatology. Outlined in the case are various investigations undertaken at this initial presentation, including rheumatologic and hematologic malignancy markers, which identified immunoglobulin A gammopathy. The systemic and topical therapies used to treat the patient’s condition are described, as well as her response to these treatments. In this discussion, we explain the epidemiology, pathophysiology, and clinical presentation of Sneddon-Wilkinson disease. Various medical conditions having known association with Sneddon-Wilkinson disease are discussed, including immunoglobulin A or immunoglobulin G monoclonal gammopathies and lymphoproliferative disorders. A comprehensive differential diagnosis for Sneddon-Wilkinson disease is provided, including immunoglobulin A pemphigus, acute generalized exanthematous pustulosis and pustular psoriasis, among others. We describe the systemic and topical therapy options for the treatment of Sneddon-Wilkinson disease, of which first line treatment is systemic dapsone. This patient serves as an excellent case of Sneddon-Wilkinson disease with unexpected immunoglobulin A gammopathy.

Autoinflammatory pustular neutrophilic diseases

This article provides a new categorization of inflammatory pustular dermatoses in the context of recent genetic and biological insights. Monogenic diseases with pustular phenotypes are discussed, including deficiency of interleukin 1 receptor antagonist, deficiency of the interleukin 36 receptor antagonist, CARD14-associated pustular psoriasis, and pyogenic arthritis, pyoderma gangrenosum, and acne. How these new genetic advancements may inform how previously described pustular diseases are viewed, including pustular psoriasis and its clinical variants, with a focus on historical classification by clinical phenotype, is also discussed.

Subcorneal pustular dermatosis in childhood: a case report and review of the literature

Subcorneal pustular dermatosis (SCPD, also known as Sneddon-Wilkinson disease) is a rare, benign, chronic, sterile pustular eruption which usually develops in middle-age or elderly women; it is rarely seen in childhood and adolescence. The primary lesions are pea-sized pustules classically described as half-pustular, half-clear flaccid blisters. Histologically the most important feature is a subcorneal accumulation of neutrophils with the absence of spongiosis or acantholysis, although acantholysis may be reported in older lesions. In this paper we present the case of a 7-year-old boy diagnosed with SCPD based on the characteristic clinical and histological features. Dapsone has been successfully used in the treatment of the disease.