Secukinumab-induced oral lichen planus in a psoriatic arthritis patient ameliorated after a switch to risankizumab.

Lichen planus is a chronic T-cell-mediated disorder in which lymphocytes, including Th17 cells, react toward the dermo-epidermal junction, which shows interface changes. Recently, IL-17-mediated changes in the oral mycobiome, including the proliferation of Candida and Aspergillus fungi, have been proposed as a possible pathomechanism of oral lichen planus (OLP). We treated a 54-year-old male who had been suffering from psoriatic arthritis. Secukinumab rapidly improved the skin and joint symptoms, but a painful erosion on the lip and thrush on the buccal mucosa appeared within 4 weeks. The erosion was histopathologically diagnosed as OLP. Although the candidiasis was successfully treated with topical miconazole nitrate, the labial OLP worsened during the secukinumab administration, despite the application of various topical agents. We finally switched from secukinumab to risankizumab, an anti-IL-23p19 agent, which dramatically improved the patient's OLP lesion in 4 weeks without candidiasis recurrence. Anti-IL-23p19 agents do not affect the oral mycobiome, and they are a potential therapeutic option for refractory OLP, including OLP induced by biologics.

Congenital nevi with hypomelanosis and fine scales.

BACKGROUND: Nevus is a hamartoma or malformation of one or more skin components, resulting in aberrant differentiation of the cell lineage(s) mostly during developmental stages. Although multiple lineages may be involved in a nevus, the combination of melanocyte and keratinocyte abnormalities has been rarely discussed. OBJECTIVES: To present two cases of congenital nevi with hypomelanosis and superficial fine scales. MATERIALS & METHODS: Skin specimens of the patients were analysed by immunohistochemistry and electron microscopy. RESULTS: Morphological and immunohistochemical studies indicated aberrant epidermal differentiation in the lesional skin specimens. Electron microscopy showed defective melanosome maturation in the melanocytes of the nevi samples. CONCLUSION: These results demonstrate that both epidermal and melanocytic lineages can concomitantly contribute to the formation of a nevus lesion.

Severe subcutaneous hematoma in a patient with psoriatic arthritis: Changes of platelet count in psoriatic patients with biologic agents.

The effectiveness of biologics has changed therapeutic strategies for psoriasis dramatically, but biologics are known to have various adverse effects. We report a 63-year-old woman with psoriatic arthritis who suddenly developed a subcutaneous hematoma after being successfully treated with adalimumab. As she had also suffered from alcoholic cirrhosis, we speculated that she had developed thrombocytopenia severe enough to cause a subcutaneous hematoma. Furthermore, we investigated the changes of platelet counts in 65 psoriatic patients treated with biologics at a single institute from 2010 to 2016. Platelet counts were found to have decreased by 17.4 ± 2.8% during adalimumab therapy (n = 16), 18.5 ± 3.8% during infliximab therapy (n = 17), 14.8 ± 2.1% during ustekinumab therapy (n = 20) and 18.5 ± 5.1% during secukinumab therapy (n = 12). Platelet counts decrease after the administration of biologics in accordance with disease activity, and there is the potential risk of subcutaneous hematoma and other adverse effects. When administrating biologics to psoriatic patients, especially to those with chronic liver disease, dermatologists should carefully monitor for thrombocytopenia.