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Published on: October 20, 2013
Eosinophilic Synovitis Masquerading as Septic Arthritis in a Pediatric Patient: A Case Report and Diagnostic Insights
Nikhil Cs1, Sharafuddeen Mammu2, Jayesh Neerngat1
1Depatment of Orthopedics, Baby Memorial Hospital, Kozhikode, India.
Insights
Eosinophilic synovitis in children can mimic septic arthritis, complicating diagnosis. Prompt synovial fluid analysis and treatment with diethylcarbamazine led to full recovery in a pediatric case.
Area of Science:
- Pediatric Rheumatology
- Pediatric Infectious Diseases
- Clinical Pathology
Background:
- Eosinophilic synovitis is a rare inflammatory joint condition.
- It often presents symptomatically similar to septic arthritis in children.
- Potential causes include allergic reactions, parasitic infections, or idiopathic factors.
Observation:
- A 4-year-old boy presented with symptoms suggestive of septic arthritis of the knee.
- Arthrotomy and synovial fluid analysis revealed marked eosinophilia.
- Histopathological examination confirmed eosinophilic synovitis.
Findings:
- The pediatric patient was treated with a 3-week course of diethylcarbamazine (DEC).
- The patient experienced complete resolution of symptoms.
- No recurrence of the condition was observed post-treatment.
Implications:
- Synovial fluid analysis is crucial for diagnosing pediatric monoarticular joint swelling.
- Eosinophilic synovitis should be included in the differential diagnosis for pediatric joint inflammation.
- Accurate diagnosis prevents misdiagnosis and unnecessary invasive treatments.
Introduction:
Eosinophilic synovitis, though rare, can closely mimic septic arthritis in children, often complicating diagnosis. This inflammatory condition is typically linked to allergic reactions or parasitic infections, though idiopathic cases have been documented.
Case Report:
We describe a 4-year-old boy initially diagnosed with septic arthritis of the knee. The patient underwent arthrotomy, and synovial fluid analysis surprisingly revealed significant eosinophilia. Histopathology confirmed eosinophilic synovitis. Following a 3-week course of diethylcarbamazine (DEC), the patient achieved full recovery with no recurrence.
Conclusion:
This case emphasizes the importance of synovial fluid analysis in pediatric monoarticular joint swelling, as eosinophilic synovitis should be considered in differential diagnoses to avoid misdiagnosis and unnecessary interventions.
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