A Rare Case of New-Onset Crohn's Disease in a Patient With Chronic Palmoplantar Pustulosis

Abstract

A 44-year-old woman who had been diagnosed with palmoplantar pustulosis (PPP) at 34 years old was diagnosed with moderate Crohn's disease (CD) based on endoscopic, radiological, and pathological findings. As treatment with corticosteroids, ultraviolet, and cyclosporin had achieved partial response, PPP had been refractory in a chronic continuous state. Oral prednisolone was initially started to treat CD, but clinical remission was not achieved. Intravenous ustekinumab was subsequently started at 260 mg for clinical remission of CD. Eight weeks after starting ustekinumab, clinical remission and mucosal healing were achieved and PPP manifestations on the palms and soles were markedly improved. Ustekinumab appears to offer an effective therapeutic option for patients with PPP but has yet to be approved for this induction in Japan. CD is a rare gastrointestinal involvement in PPP patients that requires attention.

Keywords: Clinical remission; Generalized pustular psoriasis; New-onset Crohn’s disease; Palmoplantar pustulosis; Ustekinumab.

Figure 1

Findings from colonoscopy and radiology. (a) On admission, colonoscopic image shows skipped ulcers fused with the adjacent ulcer and/or longitudinally aligned in the mucosa of the transverse colon. (b) On admission, radiological findings with contrast media reveal longitudinal ulcers as well as edematous changes and stenoses in the transverse colon. (c) At 8 weeks after starting ustekinumab, colonoscopic image shows skipped ulcer scars (white arrows) in the transverse colon.

Figure 2

Skin findings of palmoplantar pustulosis on the palms and soles. A small number of blisters and pustules, and scattered scales on diffuse erythematous skin were present on both the palms (a) and soles (b) on admission. At 8 weeks after starting ustekinumab, focal scale is present on the right palm (c) without blisters, pustules, scales, or erythema on the left palm and both soles (c, d).

Figure 3

Clinical course through 8 weeks. Crohn’s disease activity index (CDAI) and palmoplantar pustulosis area and severity index (PPPASI) on admission were 359 and 15.8, respectively. Oral prednisolone (PSL) was started at 15 mg/day accompanied by mesalazine at 3,000 mg/day. CDAI decreased to 236. In November 2022, ustekinumab was started at 260 mg based on 6 mg/kg in week 0 with the aim of clinical remission of CD and PPP. The dose of PSL was tapered off in 1 week. At 8 weeks after starting ustekinumab, clinical remission was achieved with a CDAI of 46 and PPP manifestations on the palms and soles were markedly improved (PPPASI: 0.4).