Background: Real life data often highlight side effects of certain drugs not previously reported in randomized controlled trials (RCTs). Objective. To describe cutaneous inflammatory eruptions in psoriatic patients treated with an anti IL-17A agent (secukinumab or ixekizumab). Methods: Retrospective analysis of a cohort of patients with chronic plaque psoriasis who started an anti IL17A agent between September 2016-February 2019 and who developed cutaneous inflammatory eruptions during treatment. A systematic review of similar events reported in the literature was performed. Results: Data of 468 patients were reviewed and 27 cutaneous inflammatory eruptions of 27 (5.8%) patients were collected. The eruptions appeared after a mean of 16.9 ± 17.0 weeks of therapy showing a classical acute eczema in 11 patients (40.7%), an atopic dermatitis-like rash in 11 patients (40.7%) and a psoriasiform eruption in 5 patients (18.5%). Histopathology of 12/27 cases showed epidermal spongiosis in all these variants. Conclusion: We described the clinic-pathologic features of some eczematous eruptions occurring in psoriatic patients, 3-4 months after treatment initiation with an anti IL-17A agent. Further investigations are needed to explain this phenomenon, that might be defined a paradoxical adverse event, based upon the role of IL17 in eczema pathogenesis. Keywords: psoriasis, IL17, secukinumab, ixekizumab, anti IL17, side effects, eczematous reactions

Background: The clinical variability of cutaneous sarcoidosis (CS) often makes its correct diagnosis challenging. Although traditionally employed for the diagnosis of skin tumors, during the past years dermoscopy also gained increasing interest as an aid in the clinical diagnosis of inflammatory and infectious skin manifestations in general dermatology. Objective: Our purpose was to evaluate the usefulness of dermoscopy in the differential diagnosis of CS. Methods: This was a retrospective analysis of 7 clinical and dermoscopic images of CS that were collected at dermatology clinics in France and Italy between 2005 and 2009. Results: Retrospective dermoscopic evaluation revealed small grouped, translucent orange globular structures associated with linear vessels of variable diameter in all 7 cases. In 5 cases, additional central scar-like areas were seen. Conclusion: Lesions showing dermoscopically translucent yellow to orange globular-like or structureless areas associated with linear vessels should raise the suspicion of a granulomatous skin disease, including CS.

Background. Given that clinical evaluation may underestimate the joint damage and that early treatment can slow down psoriatic arthritis (PsA) progression, screening psoriasis patients with imaging tools that can depict early PsA changes would entail clear benefits.Objective. To compare the ability of X-ray and ultrasound (US) examination in detecting morphological abnormalities consistent with early PsA in patients with psoriasis, using rheumatological evaluation as the gold standard for diagnosis.Methods. Patients with chronic plaque psoriasis and no previous PsA diagnosis attending our outpatient dermatology clinic and reporting finger/toe joint and/or tendon pain underwent X-ray and US evaluation; they were subsequently referred to a rheumatologist for clinical examination and review of imaging findings.Results. Abnormal US and/or X-ray findings involving at least one finger and/or toe (joints and/or tendons) were seen in 36/52 patients: 11 had one or more X-ray abnormalities, including erosion, joint space narrowing, new bone formation, periarticular soft tissue swelling, and periarticular osteoporosis; 36 had suspicious changes on US.Conclusion. US proved valuable in detecting joint and/or tendon abnormalities in the fingers and toes of patients with suspicious changes. The dermatologist should consider US to obtain an accurate assessment of suspicious findings.