Low Prevalence of Anti-cyclic Citrullinated Peptide Antibodies in Japanese Patients with Pustulotic Arthro-osteitis

Guselkumab for the Treatment of Palmoplantar Pustulosis: A Japanese Perspective

Palmoplantar pustulosis (PPP) is a chronic inflammatory disorder characterized by sterile pustules predominantly involving the palms and soles. PPP is refractory to various therapies such as topical ointment, oral medicine, and phototherapies. Pustulotic arthro-osteitis (PAO) is a major comorbidity of PPP that severely impairs patients’ quality of life. Recently, guselkumab, a monoclonal antibody against IL-23, has been available for the treatment of PPP in Japan. The purpose of the present review is to describe the characteristics of Japanese PPP patients and biologic therapy of PPP/PAO using guselkumab. Most Japanese dermatologists consider PPP as a distinct entity and co-existence of PPP and psoriasis is rare. However, outside Japan, PPP is often considered to be palmoplantar psoriasis, and extra-palmoplantar lesions associated with PPP are regarded as psoriasis. PPP develops or exacerbates either with or without arthralgia, following focal infections, such as tonsillitis, odontogenic infection, and sinusitis. Treatment of focal infection results in dramatic effects on cutaneous lesions as well as joint pain. By contrast, we sometimes see patients whose skin/joint symptoms do not improve after treatment of focal infection, whose focus of infection cannot be identified even in a detailed examination, and/or who refuse tonsillectomy even if strongly recommended. Such cases are considered to be indications of biologics. In this review, clinical features, pathophysiology and guselkumab therapy are discussed.

Similarity and difference between palmoplantar pustulosis and pustular psoriasis

Palmoplantar pustulosis is a chronic inflammatory disorder characterized by sterile pustules predominantly involving the palms and soles. Palmoplantar pustulosis has many similar aspects to psoriasis, either plaque and pustular type, namely familial occurrence between palmoplantar pustulosis and psoriasis, the appearance of the Köbner phenomenon, joint involvement, and nail involvement. Pustular psoriasis is classified into generalized and localized types, and there are a number of papers regarding palmoplantar pustulosis as an acral variant of localized pustular psoriasis. Many Japanese dermatologists consider palmoplantar pustulosis to be a distinct entity from pustular psoriasis, and the coexistence of palmoplantar pustulosis and psoriasis is rare. However, outside Japan, palmoplantar pustulosis is often considered to be palmoplantar psoriasis or palmoplantar pustular psoriasis, and extra-palmoplantar lesions are also considered to be psoriasis. The purpose of the current review is to compare the similarities and differences between palmoplantar pustulosis and generalized/localized pustular psoriasis. Japanese patients with palmoplantar pustulosis have a close relationship with focal infection, and the associated bone-joint manifestation exclusively involves the anterior chest wall. Furthermore, pediatric occurrence of palmoplantar pustulosis is extremely rare, and difference of genetic background between palmoplantar pustulosis and psoriasis has also been reported. Treatment of focal infection often results in dramatic effects on both cutaneous lesions and joint pain of palmoplantar pustulosis. Those findings suggest that palmoplantar pustulosis should be separately considered from either palmoplantar psoriasis or palmoplantar pustular psoriasis. The clinicopathological features and therapeutic approach of both diseases are discussed.

Characteristics of Japanese patients with pustulotic arthro-osteitis associated with palmoplantar pustulosis: a multicenter study

BACKGROUND

Pustulotic arthro-osteitis (PAO) is a major comorbidity of palmoplantar pustulosis (PPP), which is frequently seen in Japanese patients. To determine the characteristics of Japanese patients with PAO, we conducted a multicenter, retrospective epidemiologic survey at four university hospitals.

METHODS

Clinical features including age, gender, duration of disease, extrapalmoplantar lesion, smoking habit, focal infection, site of joint pain, bone scintigraphy with Technetium⁹⁹ , and therapies were retrospectively evaluated.

RESULTS

In total, 165 patients with PAO were identified among 576 patients with PPP (28.6%). The male to female ratio was 1 : 3.7, and the mean age was 50.2 years. The mean disease duration of PAO was 6.0 years. Smoking habit was observed in 104 patients. Focal infection was detected in 74 patients, who developed tonsillar infection (n = 41), sinusitis (8), odontogenic infection (40), and others (2). Fifteen patients had multifocal infection. Technetium bone scintigraphy was performed in 97 cases. Increased uptake was most frequently observed in the sternocostoclavicular regions, followed by wrist and ankle, sacroiliac joint, knee and elbow, finger and toe, lumbar spine, thoracic spine, scapula, and thigh. Patients were mainly treated with nonsteroidal anti-inflammatory drugs, methotrexate, cyclosporine, antibiotics, and biologics, as well as tonsillectomy and dental treatment.

CONCLUSION

PAO frequently involves the anterior chest wall of middle-aged women with smoking habit and is closely associated with focal infection.

Evaluation of the efficacy of granulocyte and monocyte adsorption apheresis on skin manifestation and joint symptoms of patients with pustulotic arthro-osteitis

Pustulotic arthro-osteitis, occasionally complicated with palmoplantar pustulosis, affects patients' activities of daily living. Granulocyte and monocyte adsorption apheresis selectively removes activated granulocytes and monocytes by means of extracorporeal circulation. Although the efficacy of granulocyte and monocyte adsorption apheresis in the treatment of generalized pustular psoriasis has been proved, very few reports have assessed its efficacy in the treatment of palmoplantar pustulosis and pustulotic arthro-osteitis. Ten pustulotic arthro-osteitis patients with five palmoplantar skin manifestations were treated with weekly granulocyte and monocyte adsorption apheresis over 5 weeks. Skin manifestations were assessed using palmoplantar pustulosis area and severity index, and joint symptoms were assessed using a visual analog scale of joint pain, tender joint count, swollen joint count and C-reactive protein immediately before, after and at the 3-month follow up of the five granulocyte and monocyte adsorption apheresis sessions. Two out of five patients with skin manifestations achieved more than 50% improvement in their score (remarkably improved). However, in two patients, deterioration was noted, in one of whom the skin manifestations remained unchanged at the 3-month follow up. In five out of the 10 patients, the joint symptoms were assessed as better than improved at the 3-month follow up. No deterioration was noted at the 3-month follow up. In three patients, reduction or cessation of medication for arthralgia was possible. We concluded that granulocyte and monocyte adsorption apheresis is a therapeutic option to consider when pustulotic arthro-osteitis is recalcitrant to conventional therapy.