From the Guidelines
For knee infected bursitis, vancomycin is recommended as the initial empirical therapy, with the addition of an agent active against enteric gram-negative bacilli in immunocompromised patients or those with a history of open trauma to the muscles. This recommendation is based on the practice guidelines for the diagnosis and management of skin and soft tissue infections, as outlined in the 2014 update by the Infectious Diseases Society of America 1. The guidelines suggest that vancomycin is a suitable choice for initial empirical therapy, given its effectiveness against a range of pathogens, including methicillin-resistant Staphylococcus aureus (MRSA).
When considering the treatment of knee infected bursitis, it is essential to note that the causative organisms are often similar to those found in other skin and soft tissue infections. As such, the principles of treatment outlined in the guidelines can be applied to this specific condition. Some key points to consider include:
- The importance of obtaining cultures of blood and abscess material to guide antibiotic therapy 1
- The use of imaging studies, such as MRI or CT scans, to establish the diagnosis and assess the extent of the infection 1
- The need for early drainage of purulent material to reduce the risk of complications and promote healing 1
- The potential for oral antibiotics to be used once the patient has shown clinical improvement, with a recommended duration of therapy of 2-3 weeks 1
In terms of specific antibiotic regimens, the guidelines recommend cefazolin or antistaphylococcal penicillin (e.g., nafcillin or oxacillin) for the treatment of pyomyositis caused by methicillin-susceptible Staphylococcus aureus (MSSA) 1. However, for knee infected bursitis, the initial empirical therapy with vancomycin is a more appropriate choice, given its broader spectrum of activity.
From the FDA Drug Label
Bone and Joint Infections: Due to S. aureus. The antibiotic option for knee infected bursitis is cefazolin (IV), as it is indicated for the treatment of bone and joint infections due to S. aureus 2.
- Key points:
- Cefazolin is effective against S. aureus, a common cause of bone and joint infections.
- The drug label specifically mentions bone and joint infections as an indication for cefazolin use.
- Appropriate culture and susceptibility studies should be performed to determine susceptibility of the causative organism to cefazolin.
From the Research
Antibiotic Options for Knee Infected Bursitis
- The treatment of knee infected bursitis, also known as septic bursitis, often involves the use of antibiotics 3.
- The choice of antibiotic may depend on the severity of the infection and the presence of any underlying health conditions 4.
- Common antibiotics used to treat septic bursitis include clindamycin, doxycycline, and trimethoprim-sulfamethoxazole 4, 5, 6.
- In some cases, intravenous antibiotics such as cefazolin may be used, followed by oral antibiotics like clindamycin 5.
- The duration of antibiotic treatment can vary, but it is typically continued for several days to ensure that the infection is fully cleared 4, 5.
Considerations for Antibiotic Choice
- The presence of methicillin-resistant Staphylococcus aureus (MRSA) can affect the choice of antibiotic, with some antibiotics being more effective against MRSA than others 4, 6, 7.
- Clindamycin, doxycycline, and trimethoprim-sulfamethoxazole have been shown to be effective against MRSA in some studies 6, 7.
- However, the activity of clindamycin against MRSA can be impacted by the size of the inoculum and the presence of inducible resistance 7.
- Other antibiotics, such as daptomycin and vancomycin, may also be effective against MRSA, but may be reserved for more severe infections 4, 7.