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Knee Arthrocentesis in Adults
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Etiology of septic arthritis in children: an update for the new millennium

Timothy P Young1, Lee Maas, Andrea W Thorp

  • 1Division of Pediatric Emergency Medicine, Department of Emergency Medicine, Loma Linda University Children's Hospital, Loma Linda, CA 92354, USA. tpyoung@llu.edu

The American Journal of Emergency Medicine
|August 3, 2010
PubMed

Insights

Pediatric septic arthritis cases show hip and knee involvement is common. Methicillin-sensitive Staphylococcus aureus is the most frequent cause, but community-associated MRSA is also a concern.

Area of Science:

  • Pediatric infectious diseases
  • Orthopedic infections
  • Microbiology

Background:

  • Pediatric septic arthritis epidemiology has shifted post-vaccination. Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is increasingly prevalent.
  • Understanding causative organisms and affected joints is crucial for timely diagnosis and treatment.

Purpose of the Study:

  • To describe causative organisms and joint involvement in pediatric septic arthritis.
  • To analyze trends in the post-Haemophilus influenzae type B and post-pneumococcal vaccine era, considering CA-MRSA.

Main Methods:

  • Retrospective chart review of children under 13 diagnosed with septic arthritis (2003-2007).
  • Analysis of synovial fluid Gram stain, synovial fluid culture, and blood culture results.
  • Definition of septic arthritis based on positive pathogen identification in any of these tests.

Main Results:

  • Thirteen cases of pediatric septic arthritis were identified, involving fifteen joints.
  • The hip was the most commonly affected joint (6/15), followed by the elbow (3/15).
  • Methicillin-sensitive Staphylococcus aureus (MSSA) was the most frequent pathogen (6/13), followed by CA-MRSA (2/13) and Streptococcus pneumoniae (2/13).

Conclusions:

  • Hip and knee joints remain key sites for pediatric septic arthritis.
  • Elbow involvement should also be considered in diagnosis.
  • Empiric antibiotic coverage should include CA-MRSA, MSSA, and Streptococcus pneumoniae.
Abstract

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