Acta Dermato-Venereologica 99-2CompleteContent | Page 11

152 CLINICAL REPORT Nail Involvement as a Predictor of Disease Severity in Paediatric Psoriasis: Follow-up Data from the Dutch ChildCAPTURE Registry Inge M. G. J. BRONCKERS 1 , Finola M. BRUINS 1 , Maartje J. VAN GEEL 1 , Hans M. M. GROENEWOUD 2 , Wietske KIEVIT 2 , Peter C. M. VAN DE KERKHOF 1 , Marcel C. PASCH 1 , Elke M. G. J. DE JONG 1,3 and Marieke M. B. SEYGER 1 1 Department of Dermatology, Radboud University Medical Center, 2 Department for Health Evidence, Radboud University, and 3 Radboud University, Nijmegen, The Netherlands Little is known about the relationship between nail psoriasis and psoriasis severity in children, and there has been no longitudinal assessment of psoriasis seve- rity related to nail psoriasis. The aim of this study was to assess whether nail psoriasis could serve as a pre- dictor for a more severe disease course. De-identified data were obtained from the ChildCAPTURE registry, a daily clinical practice cohort of children with psoriasis, from September 2008 to November 2015. Cross-sec- tional analyses were performed at baseline. Longitudi- nal data until 2-year follow-up were analysed by linear mixed models. Nail psoriasis was present in 19.0% of all 343 patients at baseline and cross-sectionally as- sociated with higher Psoriasis Area and Severity Index (PASI) (p  = 0.033). Longitudinal analysis demonstra- ted higher PASI (p  < 0.001) during 2-year follow-up in patients with nail involvement at baseline. These fin- dings suggest that nail psoriasis is a potential clinical predictor for more severe disease course over time in paediatric psoriasis. Key words: paediatric psoriasis; pediatric psoriasis; nail psoria- sis; psoriasis severity. Accepted Sep 11, 2018; E-published Sep 12, 2018 Acta Derm Venereol 2019; 99: 152–157. Corr: Inge M. G. J. Bronckers, Department of Dermatology, Radboud Uni- versity Medical Center, René Descartesdreef 1, PO Box 9101, NL-6500 HB, The Netherlands. E-mail: [email protected] P soriasis develops during childhood in almost one- third of cases, with an almost linear increase in pre- valence rates until 18 years of age (1–5). Nail psoriasis affects over 50% of the adult population with psoriasis, and is even more prevalent in patients with psoriatic arthritis (PsA) (6–11). Although a range of prevalence rates has been reported in children, a recent study of 4,853 children revealed an overall prevalence of 15.7% (12, 13). Evidence regarding nail psoriasis in children and its association with psoriasis severity is scarce. A recent multicentre, cross-sectional study demonstrated more severe disease in 313 children with nail involvement compared with those without nail involvement. Nail psoriasis was also associated with male sex, palmoplantar psoriasis and PsA (14). Two other cross-sectional studies in children reported no relationship between nail psoria- doi: 10.2340/00015555-3036 Acta Derm Venereol 2019; 99: 152–157 SIGNIFICANCE Psoriasis is a common chronic inflammatory skin disorder that can also affect the nails. It develops during childhood in almost one-third of cases. Early identification of children with an increased risk for a severe course of their psoria- sis is essential for adequate intervention and subsequent limitation of disease progression. This study shows that nail involvement in paediatric psoriasis is associated with a more severe psoriasis disease course during 2-year follow- up. These findings suggest that nail psoriasis is a poten- tial clinical predictor for a more severe disease course over time in children with psoriasis. sis and psoriasis severity (13, 15). Remarkably, reported signs of nail psoriasis and psoriasis severity scores in these studies were based on historical information rather than physical examination of the nails and skin. In adults, studies have found nail psoriasis to be a potential clinical predictor of developing enthesitis and PsA (16, 17), and have demonstrated an association between nail psoriasis and higher psoriasis severity scores (9, 18–21). Augustin et al. (20) reported higher Psoriasis Area and Severity Index (PASI) and Body Surface Area (BSA) scores in adult patients with nail psoriasis in a cohort of 3,531 patients. Based on these findings, they proposed to examine whether current nail involvement is predictive of a more severe psoriasis course in future. Approximately one-third of children with psoriasis experience more severe or recalcitrant disease (5, 22). Early identification of children with an increased risk for a severe disease course is essential for adequate interven- tion and subsequent limitation of disease progression. The presence of nail psoriasis as non-invasive, clinical predictor for a more severe disease course could contri- bute to this concept and become important for providing optimal treatment strategies. The aim of this prospective, observational study in a daily practice cohort of paediatric patients with psoriasis was to describe epidemiological and disease characteris- tics of children diagnosed with nail psoriasis at baseline, to determine the presence of nail psoriasis over time, to assess the relationship between nail psoriasis and repor- ted psoriasis severity scores, and, ultimately, to study the predictive value of nail psoriasis for a more severe disease course over time. This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Journal Compilation © 2019 Acta Dermato-Venereologica.