[Septic arthritis in adults]. / Septische Arthritis des Erwachsenen.

Septic arthritis is a true rheumatological emergency requiring immediate and thoughtful effort for rapid diagnosis establishment and treatment initiation. Children and elderly persons as well as immunocompromised individuals, patients with pre-existing joint damage and with inflammatory rheumatic joint diseases are preferentially affected. Bacteremia, joint surgery and intra-articular injections pose risk situations for the development of joint infections. The most frequent causative organism is Staphylococcus aureus but other relevant pathogens include coagulase-negative staphylococci, streptococci and mycobacteria. Synovial fluid analysis (e.g. appearance, cell count and microbiological examination) is the most important step to establish the diagnosis. The two main components of therapy consist of joint drainage and antibiotic treatment. The approach to periprosthetic joint infections depends on the duration of symptoms, causative organism and individual factors.

[Classification of haematogenous and post-traumatic osteomyelitis]. / Klassifikation der Osteomyelitis und Osteitis.

A classification of osteomyelitis must reflect the complexity of the disease and, moreover, provide conclusions for the treatment. The classification is based on the following eight parameters: source of infection (OM [osteomyelitis]/OT [post-traumatic OM]), anatomic region, stability of affected bone (continuity of bone), foreign material (internal fixation, prosthesis), range of infection (involved structures), activity of infection (acute, chronic, quiescent), causative microbes (unspecific and specific bacteria, fungi) and comorbidity (immunosuppressive diseases, general and local). In the long version of the classification, which was designed for scientific studies, the parameters are named by capital letters and specified by Arabic numbers, e.g., an acute, haematogenous osteomyelitis of a femur in an adolescent with diabetes mellitus, caused by Staphylococcus aureus, multi-sensible is coded as: OM2 Lo33 S1a M1 In1d Aa1 Ba2a K2a. The letters and numbers can be found in clearly arranged tables or calculated by a freely available grouper on the internet (www.osteomyelitis.exquit.net). An equally composed compact version of the classification for clinical use includes all eight parameters, but without further specification. The above-mentioned example in the compact version is: OM 3 S a Ba2 K2. The short version of the classification uses only the first six parameters and excludes causative microbes and comorbidity. The above mentioned example in the short version is: OM 3 S a. The long version of the classification describes an osteomyelitis in every detail. The complexity of the patient's disease is clearly reproducible and can be used for scientific comparisons. The for clinical use suggested compact and short versions of the classification include all important characteristics of an osteomyelitis, can be composed quickly and distinctly with the help of tables and provide conclusions for the individual treatment. The freely available grouper (www.osteomyelitis.exquit.net) creates all three versions of the classification in one step.

[Bacterial septic arthritis as rheumatological emergency]. / Bakteriell septische Arthritis als rheumatologischer Notfall.

Septic arthritis has always been a challenge to rheumatologists and surgeons. Treatment according to the current classification needs to be stage-adapted and has to be initiated rapidly as the time factor constitutes the key prognostic criterion. Failure to treat and late treatment initiation result in irreversible joint damage, functional impairment and increasing mortality. Particularly in cases of acute joint infection, clinical findings, laboratory markers of inflammation and synovial analysis lead to a rapid diagnosis of empyema in most cases. However, chronic septic arthritis may be associated with considerable diagnostic problems. In these cases further diagnostic methods, e.g. magnetic resonance imaging (MRI), computed tomography (CT) and skeletal scintigraphy may be needed. Consideration of prior treatment, extent of the infection and of the degree of joint damage is of high clinical relevance. After an optional initial antibiotic pretreatment, definitive surgical treatment is always necessary either arthroscopically or using open techniques, depending on the stage of infection. Both surgical techniques have comparable treatment success rates. Surgical radicality in removing the infected tissue is of high importance. Local and systemic antibiotic treatment is of adjuvant and supportive value. An intensive physical therapy should be initiated early to avoid functional deficits.

[Definition of the Diagnosis Osteomyelitis-Osteomyelitis Diagnosis Score (ODS)]. / Zur Definition der Diagnose Osteomyelitis - Osteomyelitis-Diagnose-Score (ODS).

AIM: The disease "osteomyelitis" is characterised by different symptoms and parameters. Decisive roles in the development of the disease are played by the causative bacteria, the route of infection and the individual defense mechanisms of the host. The diagnosis is based on different symptoms and findings from the clinical history, clinical symptoms, laboratory results, diagnostic imaging, microbiological and histopathological analyses. While different osteomyelitis classifications have been published, there is to the best of our knowledge no score that gives information how sure the diagnosis "osteomyelitis" is in general. METHOD: For any scientific study of a disease a valid definition is essential. We have developed a special osteomyelitis diagnosis score for the reliable classification of clinical, laboratory and technical findings. The score is based on five diagnostic procedures: 1) clinical history and risk factors, 2) clinical examination and laboratory results, 3) diagnostic imaging (ultrasound, radiology, CT, MRI, nuclear medicine and hybrid methods), 4) microbiology, and 5) histopathology. RESULTS: Each diagnostic procedure is related to many individual findings, which are weighted by a score system, in order to achieve a relevant value for each assessment. If the sum of the five diagnostic criteria is 18 or more points, the diagnosis of osteomyelitis can be viewed as "safe" (diagnosis class A). Between 8-17 points the diagnosis is "probable" (diagnosis class B). Less than 8 points means that the diagnosis is "possible, but unlikely" (class C diagnosis). Since each parameter can score six points at a maximum, a reliable diagnosis can only be achieved if at least 3 parameters are scored with 6 points. CONCLUSION: The osteomyelitis diagnosis score should help to avoid the false description of a clinical presentation as "osteomyelitis". A safe diagnosis is essential for the aetiology, treatment and outcome studies of osteomyelitis.