Traditional and new types of spondarthritis with special consideration of spondylodiscitis.

In rheumatology the so-called "seronegative spondarthritis" is a group of diseases characterized by the presence of HLA-B 27. This group includes the typical ankylosing spondylitis as well as atypical spondylopathies such as those occurring in psoriasis, Reiter's disease and chronic inflammatory enteropathies, which attack mainly the spine and secondarily the peripheral joints. In some severe cases, non-infectious, sterile spondylodiscitis was observed. These can lead to instability and fracture, followed by pseudarthrosis of the involved segment of the spine. In contrast to these traditional spondarthritides three new types are marked by the lack of HLA-B 27. 1) "Spondarthritis hyperostotica pustulo-psoriatica" (F. Schilling), a very rare variation of psoriatic spondylopathy, sometimes accompanied by spondylodiscitis. 2) Arthritis and spondarthritis in acne fulminans. 3) Destructive arthropathy and spondylopathy in long-term hemodialysis, occasionally occurring with spondylodiscitis, a very new type of spondarthritis. The amyloid B (beta-2-micro-globulin), discovered only four years ago, plays a dominant role in the pathogenetic chain of this disease. Details of the etiology of these very impressive diseases are presented. Destructive spondylodiscitis will no doubt be a challenge to neurosurgeons.