des Arbeitsbereichs Spondyloarhtritiden im Kompetenznetz Rheuma

Spondyloarthritis Research Section

Experimental spondyloarthritis (SpA) projects investigated the detection and behaviour of Chlamydia trachomatis:

• Detection of Chlamydia trachomatis by PCR: PCR technology for detection of Chlamydia DNA was refined, standardised, and ready to become a diagnostic tool but. Unfortunately, industry did not further endorse this important development.
  
  
• Detection and behaviour of Chlamydia trachomatis in monocytes: the cytokine profile in serum and synovial fluid in reactive arthritis was studied as persistent infection of monocytes with Chlamydia. These findings contribute to a better understanding of the interaction between host and Chlamydia trachomatis.

The core element of the SpA network within the Competence Network Rheumatology was the establishment of the German Spondyloarthritis Inception Cohort (GESPIC) which was initiated in late 2000. GESPIC is a nation-wide, prospective observational cohort on SpA patients with early disease with focus on axial SpA. The aim of this cohort was to study the course of the disease, assess socioeconomic aspects and identify predictors of a poor outcome.

Altogether 21 centres included 750 SpA patients (n=632 adult and n=118 juvenile SpA patients and) SpA patients in GESPIC. The key features of GESPIC are the following:

• SpA-subgroups: AS: n= 246; axial SpA: n=266; peripheral SpA: n=73; reactive arthritis: n=30.
  
  
• Early disease stage: patients with very early disease were included: the mean symptom duration in AS patients was 5.4 yrs with the mean duration since diagnosis of only 1.3 yrs. As many as 46% having a symptom duration < 5 yrs (mean 3.1 years).  Among axial uSpA patients, symptom duration was only 2.7 years (all had symptoms < 5 yrs) and duration since diagnosis was 0.95 yrs. Such AS cohort with short disease duration is worldwide unique. 
  
  
• High disease activity in early disease:  both AS patients and axial uSpA patients had comparable disease activity (mean BASDAI 4.0 vs 4.1) while function (BASFI 2.4 vs 3.2) and spinal mobility (BASMI 1.1 vs. 2.0) was better in axial uSpA than in AS. Persistently high disease activity:  Over a period of 1 year of follow-up as much as 31% of AS patients had a BASDAI ≥, and also 31% had an elevated CRP.
  
  
• Radiographic progression: in AS and axial uSpA patients, radiographic progression has been assessed after 2 and after 4 years. The two year datasets have currently been scored by two independent blinded readers according to the mSASSS and BASRI scoring systems. The rate of progression and predictors for poor outcome are currently being analysed.
  
  
• Cytokine and genetic studies: experimental projects associated with GESPIC related to cytokine and genetic studies. These studies confirmed the role of the TNFa -308 polymorphism. Yet, no other cytokine gene appeared to be relevant.
  
  
• Networking character of the cohort: The network of GESPIC centres served to conduct several clinical trials with anti-TNF agents and NSAIDs in AS. Further, diagnostic algorithms for early AS/axial SpA were developed based on GESPIC. This knowledge was transferred into daily clinical practice by numerous symposia, presentations at national and international meetings, and several publications in international but also national journals.
  
  
• Current status of GESPIC: the cohort is ongoing in 2007, pharmaceutical industry contributes 50% of the budget of the cohort after governmental funding was reduced by 50% in 2005. An official research application to the BMBF/ DLR to continue and expand GESPIC has been formulated in July 2007 and is currently under review.