Joint prostheses have an increased risk of acute and chronic infections that can lead to sepsis, morbidity and mortality.
Joint prostheses have an increased risk of acute and chronic infections that can lead to sepsis, morbidity and mortality. Etiology infections are more common than in natural joints with joint prostheses. These infections are often caused by contamination of the perioperative joint with bacteria or postoperative bacteremia caused by skin infection, pneumonia, dental procedures, invasive procedures, urinary tract infection or potential falls. In two thirds of cases they develop within one year after the procedure. In the first post-operative months the infections to 50% by Staphylococcus aureus, in 35% by mixed flora, in 10% are caused by gram-negative pathogens, and in 5% by anaerobes. Propionibacterium acnes is particularly common in infected prosthetic shoulder joints and requires a longer culture (up to 2 weeks) to the discovery. Candida spp. infected joint prostheses in <5% of cases. A history of symptoms and complaints are reported falls within 2 weeks before the onset of symptoms and 20% earlier surgical revisions in 25% of patients. Some patients had a postoperative wound infection that was apparently healed, then pointed for months satisfactory healing process and then eventually evolved to persistent joint pain at rest and during exercise. Symptoms may include pain, swelling and restricted movement; the body temperature may be normal. Diagnosis Clinical, microbiological, pathological and imaging criteria The diagnosis is often based on a combination of clinical, microbiological, pathological and imaging criteria. The communication between a sinus tract and the prosthesis can also be regarded as diagnostic of the infection. For cell count and culture of synovial fluid should be sampled. Röngenaufnahmen can show a loosening or periosteal reaction, but are not diagnostic. A bone scan with technetium-99m and a Szintigraphei with indium-labeled leukocytes are more sensitive than regular X-ray images, but show a lack of specificity in the immediate postoperative period. Finally periprothetisches tissue that was removed during surgery, is submitted for culture and histological analysis. Therapy arthrotomy with debridement Long-term systemic antibiotic therapy Treatment must be carried out long lasting and usually involves arthrotomy to remove the prosthesis with behutsamem debridement of all cement, abscesses and devitalized tissue. The debridement immediate prosthesis revision or placing an impregnated with an antibiotic spacer and then later (2-4 months) following the implantation of a new prosthesis using an impregnated with an antibiotic cement. A long-term systemic antibiotic therapy should be carried out in any case. Empirical therapy is initiated after an intraoperative culture was applied and typically covers both methicillin-resistant Gram-positive microorganisms (eg. As vancomycin 1 g IV every 12 h) and aerobic gram-negative microorganisms (z. B. Piperacillin / tazobactam 3.375 g iv every 6 h or 2 g ceftazidime iv every 8 h) and is revised based on the results of culture and sensitivity testing. In 38% of cases, however, it comes to the infection of the new dentures, regardless of whether they be replaced immediately or later. If patients do not tolerate surgery, long-term antibiotic therapy may be tried alone. The surgical excision with or without reinforcement is reserved with uncontrolled infection and incompetent bone usually patients. Prevention The question of whether patients with joint prostheses in the absence of other indications (eg. As valvular heart disease) require prophylactic antibiotics before procedures such as dental and urological manipulation, is currently ungklärt. Detailed recommendations are available at www.aaos.org and www.idsociety.org. At many centers, patients are screened for colonization with S. aureus by nasal cultures are created. Carrier to be treated pre-operatively with mupirocin containing ointment prior to implantation of a joint prosthesis.