Psoriasis is a chronic inflammatory skin disease affecting 1% to 3% of the world’s population1. A considerable proportion of patients with psoriasis will develop a form of inflammatory arthritis known as psoriatic arthritis (PsA). More rarely, PsA develops before the psoriatic lesions. The prevalence of PsA in patients with psoriasis varies from 7.6% to 36% according to the different populations studied2.
The inadequate response to treatment and the toxicity of traditional treatments opened the doors to the development of new therapeutic alternatives such as tumor necrosis factor-α (TNF-α) antagonists, which are utilized in patients with PsA and psoriasis for reducing the proinflammatory cell infiltration (macrophages, monocytes, keratinocytes, Langerhan’s cells, dermal dendritic cells, mast cells, and activated T cells) at the skin and synovial level3,4.
Some authors have demonstrated the utility of ultrasound (US) in PsA5,6, but to our knowledge no studies have aimed at assessing the potential of this technique in anti-TNF-α therapy monitoring in patients with psoriatic plaque. We describe potential short-term sonographic assessment in 3 patients with psoriasis on biological therapy.
The first case is a 52-year-old woman with PsA for more than 3 years. Because of the resistance to treatment with methotrexate (15 mg/wk), she started treatment with infliximab (at 5 mg/kg/infusion, administered at 0, 2, 6, and then every 8 wks). Figure 1 shows the US images taken at the beginning of treatment and 2.5 months later. A dramatic improvement is seen in terms of normalization of epidermis thickness, as shown by grayscale US, and disappearance of the dermis perfusion estimated by power Doppler technique.
The second case is a 32-year-old man, with psoriasis for more than 5 years. Due to the resistance to different therapeutic strategies (i.e., salicylic acid-vaseline, retinoids), he started treatment with etanercept (25 mg subcutaneous twice/wk). After 5 months, improvement was visible at US examination, showing a clear reduction of the epidermal and dermal thickness and disappearance of the power Doppler signal within the dermis layer (Figure 2).
The third case is a 33-year-old man, with a diagnosis of psoriasis, affected for 3 years. He started therapy with adalimumab (40 mg subcutaneous/wk). One month later, the US followup examination revealed a clear improvement of the morphostructural changes in grayscale (normalization of dermal thickness) and the perfusional status using the power Doppler technique (Figure 3).
Our report provides visual evidence that high resolution grayscale US with power Doppler technique allows a detailed morphostructural and perfusional assessment of psoriatic plaque, showing dramatic changes in patients undertaking biological therapy. Further studies of the validity of US are required to define its role for this purpose.