Final answer:
In sickle cell patients, septic arthritis is most commonly caused by Salmonella spp., with diagnosis and treatment tailored to the pathogen identified via synovial fluid analysis.
Step-by-step explanation:
In sickle cell patients, the most common causative agent of septic arthritis is Salmonella spp., although Staphylococcus aureus remains the predominant pathogen in the general population. The presence of sickle-shaped red blood cells, which obstruct tiny blood vessels, can cause pain and organ damage, including joints, making individuals with sickle cell disease more susceptible to infections from certain bacteria like Salmonella. Diagnosing septic arthritis involves aspirating synovial fluid from the affected joint for microscopic evaluation, culture, antimicrobial susceptibility testing, and possibly PCR analyses. Treatment generally includes antimicrobial drugs effective against the identified pathogen, guided by susceptibility testing. In cases where normal Staphylococcus infections are diagnosed, treatments may include β-lactams or third-generation cephalosporins depending on resistance patterns. However, the management of infections in sickle cell patients can be more complex due to their distinctive blood characteristics and potential for differing bacterial etiologies.