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Reactive arthritis induced by tonsillitis: a type of 'focal infection'
Shigeto Kobayashi1, Ginichiro Ichikawa
1Department of Rheumatology, Juntendo University Koshigaya Hospital, Fukuroyama Koshigaya-shi, Saitama, Japan. shigeto@juntendo.ac.jp
Objective:
The clinical manifestation of reactive arthritis (ReA ) induced by tonsillitis is demonstrated.
Methods:
Medical records of 21 patients with ReA induced by tonsillitis were analyzed.
Results:
Nine male and 12 female patients were recorded. The mean age was 31.7 years ranging from 20 to 51 years. The mean duration of arthritis was 29.8 months (2 weeks to 10 years). Acute or recurrent origoarthritis involved in ankle, knee and sternoclavicular joints associated with Achilles tendon enthesitis were demonstrated. Thirteen of 21 (62%) patients were demonstrated positive for ASO and/or ASK. Group A streptococcus was demonstrated in 12 of 21 (57.1%) patients and other bacteria were demonstrated by culture of tonsillar swab or from resected tonsillar microabscess. No bacteria was demonstrated in synovial fluid from 3 patients. Rheumatoid factor was demonstrated only in 2 of 21 patients. HLA-B39 and BW61 (B40) were significantly demonstrated in 5 and 7 patients (p=0.0004, 0.0006, respectively) compared with those of healthy controls. All patients were treated with antibiotics and nonsteroidal anti-inflammatory drugs (NSAIDs). Eight of 21 patients underwent tonsillectomy. Arthritis ceased after the treatments and no recurrence was found.
Discussion:
Sterile inflammatory arthritis induced by tonsillitis was cured by resection of the microabscess in the tonsils. Therefore, ReA induced by tonsillitis is one form of 'focal infection'.
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