Page 808 - Clinical Immunology_ Principles and Practice ( PDFDrive )

CHaPtEr 57 Spondyloarthritis 779

occasionally progresses to episcleritis, scleritis, or keratitis. Other Finally, pustular psoriasis is the type most closely associated
findings seen in AS, such as cardiac involvement, rarely occur. with HLA-B27. Usually, the disease appears coincident with or
Although renal involvement is mainly described in the context after the onset of skin manifestations, although approximately
of the urogenital triggering infectious process, sterile pyuria in 15–20% of patients will have preexisting arthritis. The joint
conjunction with proteinuria and microscopic hematuria are disease likewise occurs in different subtypes, as defined by the
sometimes encountered. Documented glomerulonephritis is Moll and Wright classification (Fig. 57.4), including oligoarticular,
rarely described. asymmetrical, polyarticular, symmetrical, distal interphalangeal
(DIP)-predominant, spondylitis (sacroiliitis), arthritis mutilans,
Juvenile Spondyloarthritis inflammation of DIP joints (often with nail involvement (≈80%)),
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There are two clinical subsets of JSpA: (i) undifferentiated JSpA, dactylitis (“sausage digits”), and enthesitis. Extraarticular features
which includes peripheral arthritis and enthesitis, primarily affects include nail pitting (which correlates best with DIP involvement)
the lower limbs, may also present with sacroiliac tenderness and/ and uveitis (which occurs in some series as high as 33% but in
or inflammatory spinal pain, and also includes isolated episodes most far less). Radiographically, large eccentric erosions are
of arthritis, enthesitis, tendinitis, dactylitis, and seronegative encountered.
28
enthesopathy and arthropathy (SEA) syndrome ; (ii) differenti-
ated JSpA (juvenile AS, PsA, IBD-related arthropathy) includes Enteropathic Arthritis
peripheral arthritis and enthesitis plus evidence of structural The arthritis associated with IBD (enteropathic arthritis) is most
changes in juvenile AS (radiographic sacroiliitis, spinal disease, commonly nondestructive and reversible. Two patterns have been
or tarsal ankylosis) and/or specific extraarticular symptoms (e.g., recognized (Table 57.4). Type 1 is oligoarticular, involving the
psoriasis or IBD). SEA syndrome was originally referred to the knees and ankles more than the upper extremities. It tends to
combination of enthesitis and arthritis or arthralgia as an resolve in <6 weeks. The second type has a polyarticular presenta-
idiopathic disease or as part of a well-defined SpA. 27 tion, is more likely to involve the metacarpophalangeal (MCP)
and proximal interphalangeal (PIP) joints than the lower extremi-
Psoriatic Arthritis ties, and is more likely to have a chronic course. The symptoms
29
Skin involvement exhibits four clinical patterns. The most of peripheral arthritis tend to coincide with activity of the bowel
common type is psoriasis vulgaris. Nearly as common is guttate disease in UC but not in CD. Total colectomy is associated with
psoriasis. The most severe type is the erythrodermic variety. remission of arthritis in half the patients. In contrast, axial

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FiG 57.4 Patterns of psoriatic arthritis, showing (A) rheumatoid-like distribution; (B) sausage
digits; (C) distal interphalangeal involvement; and (D) psoriatic arthritis mutilans.