Expression of Tumor Necrosis Factor-Alpha (TNF-TNF-Converting Enzyme and Matrix Metalloproteinase-3 in SAPHO Syndrome Synovium - A Rare Case Accompanied by Acrodermatitis Continua of Hallopeau: A Case Report and Review of Anti-TNF-Therapy

Synovitis-acne-pustulosis-hyperostosis-osteitis (SAPHO) syndrome is a rare disorder characterized by osteoarticular and dermatological manifestations. The denotation was first proposed by Chamot et al. in 1987 after investigation of 85 cases (Chamot et al., 1987). The most common site of SAPHO syndrome is the upper anterior chest wall, characterized by predominantly osteosclerotic lesions and hyperostosis. The axial skeleton and peripheral bones can be involved. Peripheral synovitis is also common. Skin manifestations include palmoplantar pustulosis (PPP), severe acne and various patterns of psoriasis. The pathogenesis of SAPHO syndrome has not been determined. Most of the reported series to date are anecdotal, small or uncontrolled, thus a variety of therapeutic approaches exist. Treatment remains empirical with several drugs including non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroids, antibiotics, disease modifying anti-rheumatic drugs (DMARDs) and/or bisphosphonates (BPs), but results are inconsistent and usually variable. Recently, some successful experiences with anti-tumor necrosis factor-alpha (TNF-α) agents for refractory cases have been reported (Asmussen, 2003; Ben Abdelghani et al., 2010; Castellvi et al., 2010; Deutschmann et al., 2005; Iqbal & Kolodney, 2005; Kyriazis et al., 2004; Massara et al., 2006; Moll et al., 2008; Olivieri et al., 2002; Sabugo et al., 2008; Wagner et al., 2002; Widmer et al., 2003). The therapeutic strategy was largely originated from that for spondyloarthropathies, because accumulated arguments indicate that SAPHO syndrome can be classified with the inflammatory spondyloarthropathies (Takigawa et al., 2008) and treatment with anti-TNF-α agents is now well established in spondyloarthropathies or rheumatoid arthritis (RA). Chronic proliferative synovitis is one of the most important