musculoskeletal and connective tissue disorders
Acute Infectious Arthritis
Treatment of Acute Infectious Arthritis
IV antibiotics Drainage of pus from infected joints (for acute nongonococcal bacterial arthritis or any septic arthritis with persistent effusion) Initial antibiotic selection is directed at the most likely pathogens. The regimen is adjusted based on the results of culture and susceptibility testing. Gonococcal arthritisis treated with Azithromycin1 g orally once plusceftriaxone1 g IV once a day IVceftriaxoneis continued until at least 24 hours after symptoms and signs resolve, followed bycefixime400 mg orally 2 times a day for 7 days if the organism is proved susceptible. Consult an infectious disease specialist if the patient does not improve on this regimen or cannot tolerate cephalosporins. In such cases, alternative regimens may includeazithromycinplus eithergemifloxacinorgentamicin.Ciprofloxacin750 mg orally 2 times a day may be used only if the organism is isolated and proved susceptible. Any coexisting genital infection withC. trachomatiswill be adequately treated by the initial dose ofazithromycin. Ifnongonococcal gram-positive infectionis suspected by Gram stain in anadult,or if no organisms are seen, treatment is with: A semisynthetic penicillin (eg,nafcillin2 g IV every 4 hours) A cephalosporin (eg,cefazolin2 g IV every 8 hours) Vancomycin1 g IV every 12 hours However, because methicillin resistance is now common in community-acquiredS. aureus, for patients with gram-positive cocci in clusters on gram stain or a negative gram stain whenS. aureusis suspected,vancomycinis the empiric choice. Ifgram-negative infectionis suspected (eg, in patients with immunosuppression or serious comorbid disorders, injection drug use, a recent infection with antibiotic use, or an indwelling vascular catheter), empiric treatment includes a parenteral 3rd-generation cephalosporin with antipseudomonal activity (eg,ceftazidime2 g IV every 8 hours) and, if infection is severe, an aminoglycoside. Neonatesshould be treated initially with an antibiotic that covers gram-positive infection (eg,nafcillin,vancomycin) plus an antibiotic that covers gram-negative infection (eg,gentamicinor a 3rd-generation cephalosporin such ascefotaxime). Children>3 monthsof age should be treated initially similarly to adults. Parenteral antibiotics are continued until clinical improvement is clear (usually 2 to 4 weeks), and oral antibiotics should be given at high doses for another 2 to 6 weeks according to the clinical response. Infections caused by streptococci andHaemophilusare usually eradicated after 2 weeks of oral antibiotics after IV treatment. Staphylococcal infections are treated with antibiotics for at least 3 weeks and often 6 weeks or longer, especially in patients with prior arthritis in the affected joint, immunosuppression, or whose diagnosis was delayed. In addition to antibiotics,acute nongonococcal bacterial arthritisrequires large-bore needle aspiration of intra-articular pus at least once a day, or tidal irrigation lavage, arthroscopic lavage, or arthrotomy for debridement. Joints affected with rheumatoid arthritis should generally undergo early and aggressive surgical debridement and drainage. Forgonococcal arthritiswith persistent effusion, pus is aspirated and drainage may need to be repeated as necessary. Acute bacterial arthritis requires joint splinting for the first few days to reduce pain, followed by passive and active range-of-motion exercises to limit contractures, with muscle strengthening as soon as it can be tolerated. NSAIDs (nonsteroidal anti-inflammatory drugs) can help decrease pain and inflammation once a diagnosis is confirmed. Intra-articular corticosteroids should be avoided during the acute infection. Because bacteriologic tests may be falsely negative, potent anti-inflammatory therapy should generally be avoided until a bacterial source has been definitively excluded. Opioids can be used for pain control. Viral arthritis is treated supportively. Bite wounds are treated with antibiotics and surgical drainage as necessary (see Treatment ). 