Final answer:
A patient with an acute swollen painful joint and low WBC in synovial fluid may indicate infectious arthritis, requiring laboratory tests and appropriate antimicrobial therapy based on causative organism identification and antimicrobial susceptibility testing.
Step-by-step explanation:
A patient presenting with an acute swollen painful joint and synovial fluid analysis showing white blood cell count (WBC) of less than 200 suggests a potential infectious or inflammatory process, although the actual WBC count here is relatively low for a typical bacterial infection. In cases of infectious arthritis, joint fluid is examined for signs of infection, which often include increased WBCs, the presence of bacteria, low glucose levels, and increased protein. Appropriate antimicrobial therapy is critical, along with identification of the causative organism through culture, Gram stain, and sensitivity testing to ensure the use of effective antibiotics.
In the scenarios provided, each patient experiences symptoms including pain and swelling, which can potentially be associated with an infective process, where the immune response and the presence of inflammation are key clinical indications. Diagnosis is typically confirmed through laboratory tests such as complete blood counts, blood cultures, lumbar punctures for cerebrospinal fluid (CSF) analysis, and synovial fluid analysis for joint infections. The type of organism and resistance patterns guide the choice of antibiotics, with agents such as ß-lactams, oxacillin, cefazolin, and cephalosporins being commonly used, while mycobacterial and fungal infections require long-term antimicrobial therapy.