Rheumatic manifestations of psoriasis

Psoriatic arthritis was described as a distinct rheumatic disease in the 1960s, and subsequently grouped among the spondyloarthropathies. Recently, other rheumatic manifestations of psoriasis, such as enthesopathy and osteoperiostitis, were recognized. This study attempts to examine the rheumatological and radiological manifestations of Psoriasis and their association with skin and nail disease. Eighty-one psoriatic outpatients were interviewed consecutively during 6 months. Questionnaires and indices were carried out to assess the extent and severity of skin and nail involvement, as well as the activity and severity of peripheral and axial rheumatic manifestations. Radiological examination of the hands, feet, spine and pelvis was also done for all patients. Fifty-nine psoriatic outpatients (73%) had rheumatic manifestations clinically and/or radiologically (Psoriatic arthropathy "PsA"). Clinical peripheral arthritis was found in 14 (23.7%) of the patients with PsA, being oligoarticular in 11, polyarticular in two, and exclusively of the distal interphalangeal (DIP) joints in one patient. Sacroiliitis and/or spondylitis were found in 38 (64.4%), enthesopathy in 36 (61%), dactylitis in two (3.3%), radiological DIP involvement in 24 (40.6%), and radiological osteoperiostitis in 49 (83%) of patients with PsA. Most PsA patients had more than one rheumatic manifestation, while four patients (6.7%) had isolated enthesopathy without any other rheumatic manifestations. Subungual hyperkeratosis of the nails was significantly correlated with PsA (p<0.05), as well as with clinical arthritis, enthesopathy, and DIP involvement (p<0.01), while other types of skin and nail lesions were correlated with selected rheumatic manifestations. The performance of existing criteria for PsA was poor, as individual sets favored either sensitivity or specificity. Psoriatic arthropathy (PsA), occurring in about three-quarters of hospital outpatients with psoriasis, is more common than previously thought. More sensitive and specific criteria for the diagnosis and classification of PsA need to be developed, taking into account the recently described clinical and radiological manifestations.     

A prospective, clinical and radiological study of early psoriatic arthritis: an early synovitis clinic experience

OBJECTIVE: To determine the clinical presentation and clinical and radiological outcome of early psoriatic arthritis (PsA) at 1 and 2 yr. METHODS: Patients with PsA were assessed at the St. Vincent's University Hospital Early Synovitis Clinic. Standardized clinical and laboratory assessment was performed at presentation and 1- and 2-yr follow-up. Radiographs of the hands and feet were evaluated in chronological order by two trained observers using the Sharp method modified to include the distal interphalangeal (DIP) joints. RESULTS: A total of 129 (12.7%) of 1018 patients were diagnosed with PsA [mean age at onset of arthritis was 40.4 yr (range 11-76); mean duration of disease was 9.9 months (range 0.3-48); 52 oligoarticular, 77 polyarticular]. Means and standard deviations of indices of disease activity at presentation were: 10-cm visual analogue scale = 4.8 +/- 2.7, HAQ score = 0.71 +/- 0.64, ACR functional class III/IV = 41 (35%), Ritchie Articular Index = 5.6 +/- 6, swollen joint count = 6.9 +/- 8, erythrocyte sedimentation rate = 24 +/- 26.4 mm/h, C-reactive protein = 27.6 +/- 58.5 mg/l. At presentation, 49 (38%) patients had peripheral enthesopathy, 13 patients (10%) had inflammatory spine pain and 50 (39%) patients had DIP involvement. A total of 119 had psoriasis at the time of presentation [plaque psoriasis in 112 (94%), mean age of psoriasis onset was 29.8 +/- 16.2 yr, nail dystrophy present in 78 patients (67%)]. At 1 yr of follow-up, 119 (92%) patients were reassessed and 70 (59%) were taking a disease-modifying anti-rheumatic drug (DMARD). At 2 yr, 97 (75%) patients were reassessed and 54 (56%) were taking a DMARD. Despite considerable improvement in inflammation and function scores, only 31 (26%) patients were in remission at 1 yr with 20 (21%) in remission at 2 yr. There was a low rate of DMARD-free remission [14 (12%) at 1 yr and 11 (11%) at 2 yr]. Radiographs of hands and feet were obtained for 117 (91%) patients at presentation and 86 (67%) patients at a median follow-up of 24 months (range 11-56); 47% of patients had joint erosions in hands or feet at follow-up with a mean Sharp erosion score of 3 (0) +/- 5.2 (range 0-25) and a mean Sharp narrowing score of 3.2 (0) +/- 7.5 (range 0-48). CONCLUSION: This study confirms that PsA is a chronic, progressive disease in the majority of patients. Despite clinical improvement with current DMARD treatment, PsA results in radiological damage in up to 47% of patients at a median interval of 2 yr.     

Development and early experiences of a Swedish psoriatic arthritis register

OBJECTIVES: To present a programme for a psoriatic arthritis (PsA) register (SwePsA) and to report the early experiences of a test period. METHODS: Patients with symptoms and/or signs consistent with PsA or resembling PsA are enrolled into a follow-up programme, provided the disease duration at inclusion is not longer than two years. RESULTS: Ninety-two patients were included into the programme during the test period. Sixty patients were classified as having PsA, 39 mono/oligoarticular, 19 polyarticular and two predominant axial. Thirty-two patients were classified as possible PsA. Thirty-two of the 92 included patients were followed for one year. Seven of 18 with mono/oligoarticular PsA had advanced to polyarticular PsA. Four of nine patients initially classified as possible PsA evolved into definite polyarticular PsA. Patients with polyarticular PsA had evidence of more severe disease than had patients with mono/oligoarticular PsA. CONCLUSIONS: The programme was easy to administrate and not very time-consuming in daily clinical practice. The preliminary experiences emphasize the importance of early diagnosis and the need for reliable outcome predictors for this potentially severe disorder.     

Hypothesis-free analyses from a large psoriatic arthritis cohort support merger to consolidated peripheral arthritis definition without subtyping

Current ClASsification criteria for Psoriatic ARthritis classification criteria for psoriatic arthritis (PsA) provide a preliminary definition of inflammatory articular disease. This study aimed to further characterize PsA peripheral arthritis using purely data-driven approaches for the affected joint distribution pattern. PsA patients from the Swiss Clinical Quality Management in Rheumatic Diseases (SCQM) database were clustered according to similarities in 66 swollen and in 68 tender joints. Clusters were compared in terms of other disease characteristics and studied for coincidence with traditional PsA subtypes, stability over time and treatment response upon first tumour necrosis factor alpha (TNF-α) therapy. Clustering of 957 patients resulted in an oligoarticular, a polyarticular hand dominated, a polyarticular foot dominated and a fourth cluster which was characterized by polyarticular involvement of the hands and feet. Of the traditional PsA subtypes, only a non-PsA-specific oligoarticular joint involvement pattern was retrieved by clustering. When comparing clusters in other disease manifestations, only minor and clinically probably irrelevant differences occurred. Over time, clusters were more robust than traditional PsA subtypes. Patients in different joint clusters had similar response rates upon first anti-TNF-α therapy, and minimal disease activity was achieved in 56% of 285 patients, irrespective of cluster membership. Hypothesis-free approaches to group PsA patients yield clusters with improved consistency, but without clinically important differences. Taken together, the current peripheral arthritis definition by GRAPPA without further specification into subtypes is strongly supported by the data.     

Type and outcome of reconstructive surgery for different patterns of psoriatic arthritis

OBJECTIVE: To describe our experience of musculoskeletal surgery in patients with different patterns of psoriatic arthritis (PsA). METHODS: From 1986 to 1996, 71 operations in 43 patients with established PsA were performed at our institution. The patterns of PsA recognized in this patient group were: distal PsA, oligoarticular PsA, and polyarticular PsA, with or without associated spondylitis. Surgical findings and procedure, intra- and postoperative complications were recorded. Nineteen patients were available for clinical evaluation, both by conventional surgeon generated and by patient generated self-administered questionnaires. RESULTS: The majority of patients had polyarticular PsA. All operations in patients with distal PsA were distal interphalangeal (DIP) and proximal interphalangeal (PIP) joint fusions. All operations in patients with oligoarticular PsA involved the hip or knee. Polyarticular patients underwent a range of procedures. Soft tissue contractures and bone loss required specific attention in 14 procedures. In the 19 patients who were reviewed clinically, conventional scoring of individual procedures showed good to excellent results. Patient oriented outcomes had low scores compared to a disease-free general population. CONCLUSION: The 3 principal patterns of PsA are associated with different types of surgery. Although traditional surgeon generated scores evaluating individual procedures indicated results comparable to patients who have osteoarthritis, patient generated outcome measures of global health and function scored substantially lower than a general, arthritis-free population, reflecting the burden of polyarticular involvement.     

Psoriatic arthritis: epidemiology, clinical features, course, and outcome

Psoriatic arthritis (PsA) has been defined as a unique inflammatory arthritis associated with psoriasis. Its exact prevalence is unknown, but estimates vary from 0.3% to 1% of the population. The clinical features described initially are recognised by most experienced clinicians, although they are most distinct in early disease. Initially, PsA typically presents as an oligoarticular and mild disease. However, with time PsA becomes polyarticular, and it is a severe disease in at least 20% of patients. Patients with PsA who present with polyarticular disease are at risk for disease progression. In addition to progression of clinical and radiological damage, health related quality of life is reduced among patients with PsA. It important to note that patients included in recent drug trials resemble patients followed prospectively in a clinic.     

Leflunomide addition in patients with articular manifestations of psoriatic arthritis resistant to methotrexate

In contrast to rheumatoid arthritis, in psoriatic arthritis (PsA), the efficacy of disease-modifying antirheumatic drugs (DMARDs) combination has not been documented. We conducted a retrospective study to evaluate the effectiveness of leflunomide (LEF) addition in 11 PsA patients with articular manifestations that failed to respond to methotrexate (MTX) monotherapy [disease activity score in 28 joints (DAS28) > 3.2)]. Eight of them, all with moderate disease activity (DAS28 < 5.1) at baseline, tolerated the combination. A statistically significant improvement of the mean DAS28, based on erythrocyte sedimentation rate (ESR), and its variables, and C-reactive protein (CRP) at 12–16 weeks after LEF addition was observed. Mean change of DAS28 in patients with polyarticular disease did not differ compared with those with oligoarticular. Based on the European League Against Rheumatism (EULAR) response criteria, none of our patients achieved a good response, seven had a moderate response, and one was a non-responder. The two patients with the lower DAS28 at baseline attained low disease activity (LDA, DAS28 ≤ 3.2), while none reached remission (DAS28 ≤ 2.6). Achievement of clinical remission or at least LDA has been recently proposed as the goal of treatment in PsA. Our results imply that LEF addition may serve as an alternative therapeutic modality for patients with moderately active PsA and, as lower as possible, residual disease activity after the initial therapy with MTX alone.     

Comparison of criteria for the classification of childhood arthritis

OBJECTIVE: To evaluate the applicability of the ILAR criteria for classification of childhood arthritis in an outpatient pediatric rheumatology clinic population, and to determine the proportion of children who met standard classification criteria, but failed to meet ILAR criteria for specific arthritides, and therefore became unclassifiable. METHODS: We reviewed the charts of 70 consecutive patients who had arthritis for at least 6 months, and attended the clinic between September and November 1997. Sixty-nine patients were categorized according to one of the traditional classifications [ACR for juvenile rheumatoid arthritis (JRA), European Spondylarthropathy Study Group (ESSG) for spondyloarthropathy, Vancouver Criteria for juvenile psoriatic arthritis (JPsA)], and the ILAR classification system. RESULTS: Sixty-one patients (88.4%) were classifiable by the ILAR system; 8 others failed to fulfill ILAR criteria for any specific category, and were assigned to the "other arthritis" category. Of the 29 patients with oligoarticular onset JRA, 6 were unclassified, 5 because of exclusions, and one because he fulfilled criteria for 2 categories. Presence of a family history of psoriasis accounted for most of the exclusions in the oligoarthritis and enthesitis related arthritis categories. All patients with polyarticular onset or systemic onset JRA were classified in the corresponding category in the ILAR system. One 9-year-old patient with spondyloarthropathy was reclassified as "other arthritis" because of exclusions. All 6 children with definite JPsA met ILAR criteria for PsA. Of 4 patients with probable JPsA, only 2 met ILAR criteria for PsA, a third was classified as rheumatoid factor negative polyarthritis, and the fourth was classified as "other arthritis" because of exclusions. CONCLUSION: The ILAR classification criteria applied to a group of children with chronic arthritis classified by traditional criteria results in reassignment of 11.6% of the patients, predominantly in the oligoarticular group. It will be important to determine the role of the presence of a family history of psoriasis in classifying these patients.     

Evaluation of ILAR classification criteria for juvenile idiopathic arthritis in Spanish children.

OBJECTIVE: To evaluate the proposed International League of Associations for Rheumatology (ILAR) classification criteria for juvenile idiopathic arthritis in a cohort of Spanish children. METHODS: One hundred twenty-five patients with chronic arthritis were categorized according to one of the traditional classifications and the proposed ILAR classification system after at least 6 months of disease. The traditional classifications included the European League Against Rheumatism (EULAR) criteria for pauciarticular, polyarticular rheumatoid factor (RF) negative, and systemic juvenile chronic arthritis (JCA), as well as for RF+ polyarthritis; the Vancouver criteria for juvenile psoriatic arthritis (JPsA); and the European Spondylarthropathy Study Group (ESSG) preliminary criteria for juvenile spondyloarthropathy (JSpA). RESULTS: The ILAR criteria classified 106/125 patients (84.8%). All patients with systemic and polyarticular JCA, RF+ polyarthritis, and definite juvenile psoriatic arthritis were reclassified in the corresponding ILAR category. In contrast, only 80% of pauciarticular JCA and 47% of JSpA patients could be allocated to the ILAR oligoarthritis (47/59 patients, 35 persistent and 12 extended) and enthesitis related arthritis (ErA. 8/17 patients) categories. Two children with probable PsA were reclassified in the RF- polyarthritis category. Nineteen patients (15.2%) were allocated to the ILAR "other arthritis" group, 13/19 because they did not fulfill criteria for any of the other categories (12 due to family history of psoriasis and one because of family history of HLA-B27 associated disease). The remaining 6 patients met criteria for 2 categories, RF- polyarthritis and either ErA (n = 5) or PsA (n = 1). No differences other than family history of psoriasis were found in any of the variables studied between pauciarticular JCA patients classified in the oligoarthritis (n = 47) and those in the "other arthritis" (n = 11) ILAR categories. CONCLUSION: The proposed ILAR criteria allocated 84.8% of the patients classified by traditional criteria. Family history of psoriasis (n = 12) and polyarticular onset of disease in patients with ErA (n = 5) were responsible for most of the exclusions from other ILAR categories.     

Progression of peripheral joint disease in psoriatic arthritis: a 5-yr prospective study

OBJECTIVE: To assess the evolution of disease subgroups and the frequency of progression of peripheral joint disease in a prospectively studied cohort of patients with psoriatic arthritis (PsA). METHODS: The cohort was identified as the first consecutive 100 patients attending a psoriatic arthritis clinic and who had been the subject of a previously published cross-sectional retrospective study. Nine of the 100 patients had died, three declined follow-up and one could not be traced. The remaining 87 patients (49 females, 38 males) completed the study proforma at a median follow-up interval of 65 months (range 39-90). An analysis of initial plasma viscosity compared with rates of progression of joint score was performed. RESULTS: Eighteen patients changed subgroup; 11 had an increase in the number of joints involved, six a decrease, and one changed from an oligoarticular pattern to predominant spondylitis. Within the polyarticular group 37/51 patients had an increase in the number of joints involved. For the whole population, there were significant increases in the number of joints involved (median 6 vs 11, P < 0.001 Wilcoxon signed rank) and Health Assessment Questionnaire scores (median 0.375 vs 0.5, P < 0.001). The median rate of joint progression was 0.42 peripheral joints per year (range 0-7.2). However, the rate of peripheral joint involvement was highest in the first year of arthritis (median 4.0 joints/yr) as measured in 13 patients who had onset within 12 months of baseline assessment. There were no significant differences in skin and nail scores although nine more patients had developed nail disease. There was a significant correlation between the initial viscosity and rate of progression of joint damage (Spearman correlation, P < 0.011). CONCLUSIONS: Peripheral joint disease is progressive in the majority of patients with PsA and reinforces the need for effective monitoring and treatment.     

Distal interphalangeal joint abnormalities in children with polyarticular juvenile rheumatoid arthritis

Involvement of the distal interphalangeal (DIP) joints was noted radiographically in 24 (43.6%) of 55 patients with polyarticular juvenile rheumatoid arthritis. DIP changes were apparent later in the course of the disease and were less severe than in other affected joints. Soft tissue swelling and joint space narrowing were the most frequent abnormalities in the DIP joints. Erosive changes and angular deformities were uncommon. There was no significant correlation between DIP joint involvement and sex, age at presentation, involvement of the hands and wrists at presentation, or positivity of either rheumatoid factor or antinuclear antibody. There was a strong correlation between the presence of extraarticular signs and symptoms and involvement of the DIP joints; however, this may reflect the greater severity of the disease in these patients generally.     

Hip joint disease in psoriatic arthritis: risk factors and natural history

OBJECTIVE: To determine the natural history of hip joint disease in psoriatic arthritis (PsA) and identify clinical risk factors for its early identification. PATIENTS AND METHODS: 504 patients with PsA according to ESSG criteria were studied. Mean follow up was 5.7 years (range <1-45). Mean age at onset of psoriasis was 32 years and of PsA, 39 years. The most common pattern of PsA at onset was oligoarticular (49%) and at the latest examination, polyarticular (65%). Sacroiliitis or spondylitis was diagnosed in 94 (18.7%) patients. RESULTS: 32 (6.3%) patients developed psoriatic hip arthropathy, and of these, 26 (81%) also had sacroiliitis or spondylitis. In 7/17 (41%) patients the hip became affected within 1 year after the onset of PsA. Hip disease occurred more often in younger patients. Sex, pattern of peripheral arthritis, duration of psoriasis before arthritis affected the distal interphalangeal joints, dactylitis, or enthesitis were not associated with the risk of hip disease. Seventeen patients were followed up and nine required hip arthroplasty. Sixteen (50%) first had arthroplasty within 5 years after the onset of hip pain. CONCLUSIONS: Psoriatic hip arthropathy occurs infrequently in PsA and is associated with earlier onset of arthritis and psoriatic spondylitis. Bilateral hip involvement and rapid progression to hip arthroplasty are common.     

Psoriatic arthritis: one or more diseases?

Psoriatic arthritis (PsA) is a common, debilitating auto-immune disease with diverse clinical features. In this paper, published evidence is examined, which addresses the issues that (a) PsA exists; and (b) PsA can or cannot be viewed as a distinct rheumatic disease from other spondyloarthritides. Evidence derived from epidemiological, clinical, genetic and immunohistological studies is included. Summarizing the evidence, it is clear that PsA does indeed exist, with the prevalence of rheumatic disease in patients with psoriasis (Ps) higher than would be expected. Certain clinical features also occur more commonly in PsA, although none can differentiate consistently from other arthropathies. Both genetic and immunohistological studies suggest that PsA, both oligo- and polyarticular disease, can be clearly separated from rheumatoid arthritis and that it belongs to the family of spondyloarthritides. The presence of Ps may confer a more severe clinical phenotype with poor radiological outcome. It may be that, with time, a specific genetic marker or diagnostic feature will emerge; additional, more detailed pathogenic studies are required. In the meanwhile, particularly with new treatments being evaluated, it is important to continue to develop specific classification or diagnostic criteria and to define both clinical and laboratory-based outcome measures.     

Synovitis in Psoriatic Arthritis: Immunohistochemistry,Comparisons With Rheumatoid Arthritis,and Effects of Therapy

Psoriatic arthritis (PsA) is a chronic inflammatory arthropathy associated with psoriasis that affects the peripheral joints, spine, and entheses. Most patients with PsA present with peripheral synovitis of the oligoarticular or polyarticular subtype. As one of the targets of this disease, studies on the synovium may provide insight into the mechanisms involved in this condition. Key findings from the available studies comparing synovial tissue of PsA and rheumatoid arthritis patients are discussed in this review. Also, changes in the synovial infiltrate, expression of proinflammatory cytokines and adhesion molecules, and vascularity in synovial tissue after treatment with various medications are addressed. Finally, a model for proof-of-principle study design using serial synovial biopsies is described, which could be used to predict clinical (in)efficacy in early clinical trial design in PsA.     

Evaluation of revised International League of Associations for Rheumatology classification criteria for juvenile idiopathic arthritis in Spanish children (Edmonton 2001)

OBJECTIVE: To evaluate the revised (Edmonton 2001) International League of Associations for Rheumatology (ILAR) classification criteria for Juvenile Idiopathic Arthritis (JIA) in a cohort of Spanish children. METHODS: One hundred twenty-five patients with chronic arthritis categorized according to traditional criteria and to the first revision of ILAR JIA criteria (Durban 1997) were reclassified according to the second JIA criteria revision (Edmonton 2001). RESULTS: Edmonton criteria allocated 92% of the patients classified by traditional criteria in their corresponding ILAR categories. Most patients with systemic (94%), pauciarticular (91%) and polyarticular (88%) juvenile chronic arthritis as well as those with juvenile spondyloarthropathy (94%) were reclassified in the corresponding ILAR categories. Two children with probable psoriatic arthritis (PsA) were reclassified in the rheumatoid factor-negative (RF-) polyarthritis category, whereas only one of 2 children with definite PsA could be allocated to the ILAR PsA class. Ten patients (8%) constituted the undifferentiated arthritis group, 8 because of psoriasis in a first-degree relative, one because of the presence of RF in a girl with oligoarthritis, and another because of psoriasis in a boy who was HLA-B27-positive. In comparison with the Durban JIA criteria the Edmonton revision decreased the number of patients whose arthritis fulfilled criteria in no category or in 2 or more categories (from 19 to 10), and delineated better the population included in the RF- polyarthritis category. CONCLUSION: The Edmonton criteria made the ILAR classification more transparent and easy to apply. Family history of psoriasis was responsible for most allocations to the undifferentiated arthritis category (8/10).     

Patients with antinuclear antibody-positive juvenile idiopathic arthritis constitute a homogeneous subgroup irrespective of the course of joint disease

OBJECTIVE: We recently hypothesized that in the International League of Associations for Rheumatology (ILAR) classification of juvenile idiopathic arthritis (JIA), the presumably homogeneous patient group characterized by early onset of disease, a female predilection, the presence of antinuclear antibodies (ANA), asymmetric arthritis, and the risk for iridocyclitis is classified into different categories. We sought to investigate whether ANA-positive patients belonging to the ILAR categories of oligoarthritis and rheumatoid factor (RF)-negative polyarthritis share homogeneous features and to compare these features with those of ANA-negative patients with JIA in the same categories. METHODS: We identified patients who were followed up during a 15-year period. All patients had JIA according to the ILAR criteria, with oligoarticular or polyarticular onset. ANA positivity was defined as 2 or more positive results at a titer of >or=1:160. Demographic and clinical features, including the number of joints involved over time and measures of JIA severity at the last followup visit, were recorded retrospectively. RESULTS: A total of 256 patients were included: 190 were ANA positive (109 had persistent oligoarthritis, 48 had extended oligoarthritis, and 33 had RF-negative polyarthritis), and 66 were ANA negative (35 had RF-negative polyarthritis, and 31 had oligoarthritis). All patients who were positive for ANA were similar in terms of age at disease presentation, female-to-male ratio, and frequency of symmetric arthritis and iridocyclitis. Compared with ANA-positive patients with polyarticular disease, ANA-negative patients with polyarticular arthritis were older at disease presentation and had a lower frequency of iridocyclitis, a higher frequency of symmetric arthritis, a greater cumulative number of joints affected over time, and a different pattern of joint disease, with a greater frequency of shoulder and hip involvement. The strong relationship between the presence of ANA and younger age at disease presentation, asymmetric arthritis, and development of iridocyclitis was confirmed by multivariate regression analysis. CONCLUSION: Our results support the hypothesis that patients with similar characteristics are currently classified into different JIA categories. The value of ANA positivity as a possible modifier of the current classification system deserves consideration.     

Prevalence of psoriatic arthritis in psoriasis patients according to newer classification criteria

The aim of this study is to determine the prevalence of psoriatic arthritis (PsA) according to CASPAR criteria, ASAS peripheral and axial SpA criteria, and New York criteria for AS. The first 100 patients consecutively attending a psoriasis dermatology clinic were assessed. Demographic and clinical data were collected; all patients were questioned and examined for joint manifestations. Rheumatoid factor and radiographies of hands, feet, cervical spine, and pelvis for sacroiliac joints were obtained. X-rays were read independently by two experienced observers in blind fashion. Patients with objective joint manifestations, both axial and peripheral, were evaluated for fulfillment of CASPAR, ASAS peripheral and axial, and New York criteria. Median age 48 years; 93 % of patients had psoriasis vulgaris and 56 % nail involvement. Seventeen patients had peripheral arthritis as follows: nine mono/oligoarticular and eight polyarthritis. Median arthritis duration was 8 years. Seventeen percent of patients fulfilled CASPAR and ASAS peripheral criteria, 6 % New York, and 5 % ASAS axial criteria. Patients who met CASPAR criteria showed a significantly higher psoriasis duration compared to those without arthritis (M 16 vs. 10 years, p?=?0.02), and a higher frequency of nail involvement (88.2 vs. 49.4 %, p?=?0.003). Five patients (29.4 %) fulfilled ASAS axial criteria; all of them had peripheral involvement as follows: mono/oligoarticular in three patients and polyarticular in two. Patients with peripheral and axial involvement presented a significantly higher frequency of erythrodermic psoriasis compared to the other patients (35.3 vs. 1.2 %, p?=?0.0006 and 80 vs. 16.7 %, p?=?0.02). Prevalence of PsA, for CASPAR and ASAS peripheral criteria, was of 17 %. Five percent of patients met ASAS axial criteria, while 6 % met New York criteria. Worth noting, few patients without signs or symptoms of arthritis had radiological changes, both axial and peripheral, precluding a proper classification.     

Patients with juvenile psoriatic arthritis comprise two distinct populations

OBJECTIVE: Psoriatic arthritis (PsA) in children is clinically heterogeneous. We examined a large population of children with juvenile PsA for evidence of phenotypic clustering that could suggest the presence of distinct clinical entities. METHODS: We reviewed the medical records of 139 patients meeting the Vancouver criteria for juvenile PsA. To identify segregation into phenotypic groups, we compared younger patients with their older counterparts and subjected the whole population to 2-step cluster analysis. RESULTS: Among patients with juvenile PsA, the age at onset is biphasic, with peaks occurring at approximately 2 years of age and again in late childhood. Compared with children ages 5 years and older, younger patients are more likely to be female, exhibit dactylitis and small joint involvement, and express antinuclear antibodies. Progression to polyarticular disease (>or=5 joints) is more common in younger children, although joint involvement remains oligoarticular in the majority of children. In contrast, older patents tend to manifest enthesitis, axial joint disease, and persistent oligoarthritis. Uveitis is equally represented in both age groups. Despite a higher utilization of methotrexate therapy, younger patients required, on average, more than twice as long to achieve clinical remission (23 months versus 9.2 months; P = 0.044). Cluster analysis identified largely overlapping subgroups but suggested that the presence of dactylitis, rather than age, has the greatest capacity to predict essential features of the clinical phenotype. CONCLUSION: Juvenile PsA comprises 2 distinct populations of patients. Although the pathophysiologic correlate of this finding remains undefined, future studies should avoid the assumption that PsA in childhood constitutes a single etiologic entity.     

The Swedish early psoriatic arthritis register-- 2-year followup: a comparison with early rheumatoid arthritis

OBJECTIVE :Patients with symptoms and signs compatible with psoriatic arthritis (PsA), with or without psoriasis, have been documented in the Swedish Early Psoriatic Arthritis (SwePsA) register. Our aim was to find markers for disease progression and to evaluate treatments for PsA using these data. METHODS: Patients referred to rheumatology outpatient clinics within 2 years of onset were assessed on inclusion and at followup 2 years later. Data collection was performed according to the program for SwePsA, and classification was as described by Moll and Wright and the ClASsification Criteria for Psoriatic ARthritis (CASPAR). Remission was recorded if the patient had no tender or swollen joints and if erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were within the reference range. Patients with early rheumatoid arthritis (RA) recruited from the Swedish Early Rheumatoid Arthritis Register (Ramona) provided comparison data. RESULTS: One hundred thirty-five patients with PsA according to CASPAR were assessed; 44% were classified as having mono/oligoarthritis and 47% as polyarthritis. Two patients (1%) were in remission initially, and 23 (17%) at followup. Patients with polyarticular disease had the highest inflammatory activity, measured by swollen and tender joint counts, ESR, Health Assessment Questionnaire, and self-assessment by visual analog scale of pain and global disease activity. Dactylitis was associated with radiological findings. Compared with RA patients, they had significantly lower CRP, ESR, and number of swollen joints (p = 0.0003, p = 0.0026, p = 0.0380, respectively) at inclusion, but equal numbers of tender joints and self-assessment of pain and disease activity. CONCLUSION: About half the patients had polyarthritis and the other half had mono/oligoarthritis at followup after 2 years. Patients with polyarthritis had the highest inflammatory activity. Apart from ESR, CRP, and swollen joint count, there were no significant differences in activity between RA and polyarticular PsA.