Interviews with paediatric rheumatologists about psoriasis and psoriatic arthritis in children: how can specialties learn from each other?

Opportunities exist for cross-specialty learning between dermatology and other medical disciplines; to the benefit of patients, clinical decision making and professional development. The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) promotes the concept of ‘psoriatic disease’ to encompass psoriasis and psoriatic arthritis, and in their new disease management recommendations emphasise the importance of collaborative working between dermatologists and rheumatologists1. Whilst the group primarily focuses on adult disease we suggest that a similar model should exist for the paediatric population. 
 
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DOI: 10.1111/bjd.15090 DEAR EDITOR, Opportunities exist for cross-specialty learning between dermatology and other medical disciplines, to the benefit of patients, clinical decision making and professional development. The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis promotes the concept of 'psoriatic disease' to encompass psoriasis and psoriatic arthritis, and their new disease management recommendations emphasize the importance of collaborative working between dermatologists and rheumatologists. 1 While the group focuses primarily on adult disease we suggest that a similar model should exist for the paediatric population. Juvenile psoriatic arthritis (JPsA) is a separate disease from psoriatic arthritis in adults and is a distinct subset of juvenile idiopathic arthritis, an inflammatory arthritis with onset under the age of 16 years and unknown aetiology. 2 Cutaneous psoriasis and psoriatic nail disease are both core components of the diagnostic classification of JPsA. 3 However, recognition of psoriasis in children can be more challenging compared with adult disease, as the signs are often more subtle. 4 Local experience in our Nottingham combined paediatric dermatology and rheumatology clinics has demonstrated the shared benefit of cross-speciality learning for the assessment and management of JPsA. To identify learning opportunities we conducted structured telephone interviews with U.K. paediatric rheumatologists. The interviews aimed to ascertain paediatric rheumatologists' current practice for assessing for psoriasis, the impact a diagnosis of JPsA has on the management of arthritis, experience of the presentation of skin and joint disease, and recommendations on improving the detection of JPsA.
In the U.K., paediatric rheumatology is a specialist commissioned service with 12 designated centres; a rheumatologist at each centre was identified through the British Society of Paediatrics and Adolescent Rheumatology. Rheumatologists were contacted and provided study information by e-mail, verbally consented for audio recording and undertook the interviews as part of service evaluation. The interviews were conducted by one interviewer (E.B.-T.) following an interview guide of open and closed questions and were transcribed as intelligent verbatim. Categorical responses were analysed quantitatively as percentages, and framework analysis was used to identify common themes in open responses. 5 Rheumatologists at 10 of 12 (83%) centres of paediatric rheumatology expertise were interviewed, based in England, Scotland and Northern Ireland. These form a moderate sample that is likely to be representative of current paediatric rheumatology practice. All clinicians had children with inflammatory arthritis under their care. Table 1 presents the results of questions about the assessment for psoriasis and the impact a diagnosis of JPsA has on the management of arthritis. Hidden-site psoriasis was defined as psoriasis occurring behind the ears or in the umbilicus, flexures, groin, genitals or natal cleft. Only 50% of rheumatologists ask about or examine at least one hidden site, and a smaller number examine the groin (20%), genitals (10%) and natal cleft (10%). However, paediatric rheumatologists rated their confidence in assessing for psoriasis on average at 6Á4 (0, no confidence at all; 10, very confident).
The three most frequent suggestions to improve rheumatologists' recognition of psoriasis were a close working relationship with dermatologists, experiential training and a diagnostic tool. The majority of rheumatologists felt a diagnosis of JPsA compared with other juvenile idiopathic arthritis subtypes made an impact on the explanation given to patients and families (70%), the treatment plan (80%) and long-term outcomes (70%), highlighting the likely chronic and aggressive course of JPsA.
Eight rheumatologists (80%) found it difficult to estimate the percentage of patients presenting with skin, joint or simultaneous disease. Nine rheumatologists (90%) recommended that paediatric dermatologists could use the Paediatric Gait Arms Legs Spine (pGALS) tool to screen children with psoriasis for JPsA, and one-third (30%) commented that it is important to practise the technique. 6 Opportunities exist for paediatric dermatologists and rheumatologists to learn from each other. JPsA may be missed by paediatric rheumatologists if psoriasis occurring in hidden sites is not asked about and examined. It is important to examine these sites as there is sometimes discordance between patients' awareness of psoriasis and changes detected on examination. Future work could further explore dermatological practice among rheumatologists, including recognition of nail disease and disease severity. Dermatologists are best placed to develop paediatric psoriasis training material and diagnostic guidance for their rheumatology colleagues.
Currently there is no specific guidance on how children with psoriasis should be screened for JPsA. Available screening Table 1 Responses to questions about how paediatric rheumatologists assess children with inflammatory arthritis for psoriasis and the impact a diagnosis of juvenile psoriatic arthritis has on their management of arthritis. Hidden psoriasis refers to psoriasis behind the ears and in the umbilicus, flexures, groin, genitals and natal cleft

Structured question Number of respondents
When assessing children with inflammatory arthritis, do you routinely ask any questions about skin disorders?
Yes 10/10 (100%). Directly ask about psoriasis 7/10 (70%) When assessing children with inflammatory arthritis, are there any specific areas of the body where you ask about changes to the skin?
Yes, 8/10 (80%); no, 2/10 (20%). Specific rheumatological features in JPsA, 7/10 (70%), which include dactylitis 5/10 (50%), enthesitis 1/10 (10%), small joints of the hand/DIP 4/10 (40%), minimal swelling/drier synovitis/subtle 3/10 (30%), more aggressive 1/10 (10%), systemic inflammation 1/10 (10% tools for adult psoriatic arthritis have not been validated for use in children. 7 Paediatric rheumatologists are likewise best placed to develop screening recommendations and related training for JPsA assessment by dermatologists. From these interviews pGALS should be considered as an annual screening tool for use in paediatric dermatology clinics. We conclude that these interviews provide clear examples of the need for paediatric dermatologists and rheumatologists to learn from each other. Working groups, consensus work and research studies are needed to take forward these strategies to improve the detection of JPsA. At a time of limited healthcare resources, this work should open discussions about electronic multidisciplinary working and teaching material.