Stoll Matthew L, Zurakowski David, Nigrovic Lise E, Nichols David P, Sundel Robert P, Nigrovic Peter A
Children's Hospital Boston, Harvard Medical School, Massachusetts 02115, USA.
Arthritis Rheum. 2006 Nov;54(11):3564-72. doi: 10.1002/art.22173.
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.
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.
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.
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.
儿童银屑病关节炎（PsA）在临床上具有异质性。我们研究了大量青少年PsA患儿，以寻找可能提示存在不同临床实体的表型聚类证据。
我们回顾了139例符合青少年PsA温哥华标准患者的病历。为了确定表型分组，我们比较了年龄较小的患者与其年龄较大的同龄人，并对整个人群进行了两步聚类分析。
在青少年PsA患者中，发病年龄呈双相性，高峰分别出现在约2岁时和儿童晚期。与5岁及以上儿童相比，年龄较小的患者更可能为女性，表现出指（趾）炎和小关节受累，并表达抗核抗体。年龄较小的儿童进展为多关节疾病（≥5个关节）更为常见，尽管大多数儿童的关节受累仍为少关节性。相比之下，年龄较大的患者倾向于表现为附着点炎、轴性关节疾病和持续性少关节炎。葡萄膜炎在两个年龄组中的发生率相同。尽管甲氨蝶呤治疗的使用率较高，但年龄较小的患者平均需要两倍以上的时间才能达到临床缓解（23个月对9.2个月；P = 0.044）。聚类分析确定了大部分重叠的亚组，但表明指（趾）炎的存在而非年龄具有最大的能力来预测临床表型的基本特征。
青少年PsA包括两个不同的患者群体。尽管这一发现的病理生理相关性尚不清楚，但未来的研究应避免假设儿童期PsA构成单一病因实体。
