[Laboratory studies in pediatric bone and joint infections]

Area of Science:

• Orthopedics
• Infectious Diseases
• Clinical Pathology

Background:

• Acute osteomyelitis and septic arthritis diagnosis is primarily clinical.
• Acute-phase reactants aid initial diagnosis but have limitations.

Purpose of the Study:

• To evaluate the utility of acute-phase reactants in diagnosing and monitoring bone and joint infections.
• To compare the reliability of white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP).

Main Methods:

• Clinical diagnosis as the gold standard.
• Analysis of acute-phase reactant levels (WBC, ESR, CRP) in patients with suspected bone and joint infections.
• Monitoring CRP kinetics during treatment.

Main Results:

• White blood cell (WBC) count is often normal (up to 80%) and unreliable.
• Erythrocyte sedimentation rate (ESR) is elevated in 80% of cases.
• C-reactive protein (CRP) is elevated in over 80% of cases and shows rapid kinetics, making it useful for treatment response monitoring.
• Patients requiring surgical drainage have delayed CRP normalization.
• Procalcitonin (PCT) shows low sensitivity for bone and joint infections despite being a marker for severe infections.

Conclusions:

• CRP is a valuable and reliable marker for diagnosing and monitoring acute osteomyelitis and septic arthritis.
• CRP's rapid kinetics facilitate effective tracking of treatment response.
• WBC count is an unreliable diagnostic indicator for these conditions.