Chlamydia pneumoniae arthritis in a patient with common variable immunodeficiency

Background: Arthritis is an important and sometimes life-threatening complication in patients with common variable immunodeficiency (CVID). Objective: To describe a patient with CVID and arthritis due to Chlamydia pneumoniae, which is usually regarded as a respiratory tract pathogen and has not previously been detected in the synovial fluid by cell culture technique. Methods: Routine bacteriologic, virologic, mycologic, and tuberculosis cultures were performed. The patient's synovial fluid was examined for fastidious organisms that might be causative pathogens of arthritis, such as chlamydiae, and special cell culture methods were used. Serologic tests were performed to determine viral and bacteriologic etiology. Results: The patient had a history of recurrent respiratory tract infections, and the latest exacerbation was followed by arthritis. Cytologic examination of the fluid yielded abundant lymphocytes. Chlamydia pneumoniae was detected in synovial fluid specimens by cell culture technique. Her nasopharyngeal swab and sputum culture specimens were also positive for this pathogen. She was diagnosed as having arthritis caused by C pneumoniae and was given antibiotherapy. Conclusion: Chlamydia pneumoniae should be kept in mind as a causative pathogen in patients with CVID and arthritis, especially when effusion fluid is full of lymphocytes rather than polymorphonuclear cells and no organism is grown on routine cultures.