Septic Arthritis: Microbial Etiology, Diagnosis, and Treatment

Septic arthritis is a serious musculoskeletal infection characterized by the invasion of a joint space by microorganisms, leading to inflammation and joint destruction.

Microbial Etiology

The most common causative pathogens of septic arthritis include:

• Staphylococcus aureus - The most frequent bacterial agent.
• Streptococcus species - Including Group A and Group B streptococci.
• Neisseria gonorrhoeae - Common in sexually active young adults.
• Gram-negative bacilli - More prevalent in immunocompromised patients.

Diagnosis

Diagnosis of septic arthritis relies on a combination of clinical evaluation, laboratory testing, and imaging studies:

• Clinical Signs - Joint pain, swelling, erythema, fever, and reduced mobility.
• Synovial Fluid Analysis - Elevated WBC count, low glucose levels, and positive Gram stain or culture.
• Imaging - X-ray, ultrasound, or MRI can help assess joint damage.

Treatment

Management of septic arthritis includes antimicrobial therapy and joint drainage:

• Empiric Antibiotic Therapy - Based on patient risk factors and likely pathogens.
• Joint Aspiration - Removing infected synovial fluid to relieve symptoms.
• Surgical Intervention - Arthroscopic or open drainage in severe cases.
• Supportive Care - Pain management and physical therapy for joint recovery.

Conclusion

Early recognition and timely treatment of septic arthritis are crucial to prevent joint damage and systemic complications. A multidisciplinary approach involving infectious disease specialists, rheumatologists, and orthopedic surgeons ensures optimal patient outcomes.