Tehran University Medical Journal

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Background: Determining the etiologic causes of septic arthritis is of the most importance. Goal of this study was to investigate presence of staphylococcal enterotoxins A, B, C and Toxic Shock Staphylococcal toxin-1 in the synovial fluid of patients with arthritis.

Methods: This cross-sectional study was performed in the Pediatric and Orthopedic Wards of Hazrat Rasoul Hospital in Tehran, Iran during 2008- 2010. Gram stains, conventional cultures, direct detection of soluble bacterial antigens were used to detect H. influenza, S. pneumonia, group B streptococci, and N. meningitidis while Latex particle agglutination test was used for staphylococcal supper antigens (by enzyme immunoassays) upon synovial fluid tapping of 62 individuals (5 mo to 16 yrs, mean=113.8 yrs). P<0.05 was considered statistically significant.

Results: Positive SF cultures (n=11): 5 positive cases of S. aureus 5 S. pneumonia 1 H. influenza, and 1 Klebsiella. Positive gram stains: 10% and positive LPA: 4%. Staphylococcal arthritis was diagnosed in 7 (39%) cases upon positive culture or positive gram stain. The most common type was TSST-1 (47%) and the least common was enterotoxin B (18%). Isolation of S. aureus (positive culture) was correlated to presence of enterotoxin A in synovial fluid but not to enterotoxins B, C or TSST-1.

Conclusion: Staph. aureus had a prominent role in arthritis. 47% of cases with negative culture for S. aureus had at least one type of staphylococcal super antigens in the synovial fluid. Searching for antigens of usual organisms or staphylococcal supper antigens could be helpful for diagnosis and

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Background: Staphylococcus aureus secretes numerous superantigenes which trigger the inflammatory mechanisms of sinus mucosa and cause chronic rhino-sinusitis. This study was designed to evaluate the role of staphylococcus aureus superantigens in polyp tissues of patients with chronic rhino-sinusitis in comparison with a control group.
Methods: Polyp tissue samples of 28 patients and mucosal specimens of 19 healthy individuals were evaluated for staphylococcus aureus bacterium superantigens, exotoxins A, B, C and D and TSST-1 with RT-PCR and ELISA methods Rasoul Akram Hospital during 2 years.
Results: Polymerase chain reaction (PCR) results revealed that 88.2% of the patients and 45.5% of the controls had at least one type of superantigen (P=0.03). Evaluation of superantigens using ELISA method showed presence of at least one type of superantigen in the nasal samples of all patients and in 35.3% of the controls (P<0.001).
Conclusion: A relationship between staphylococcal superantigens and nasal polyps is concluded from this study which indicates the probable role of these superantigens in the pathogenesis of nasal polyposis.

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Background: Nasal polyp (NP) is a benign mucosal mass located in both sinuses and nares which is mostly seen in association with cystic fibrosis, asthma or oversensitivity to aspirin. The prominent histological feature of NP is inflammatory cell infiltration with eosinophil predominance. Superantigens role in causing NP complications is already proven. Superantigens, which are mostly originated from Streptococci and Staphylococci, activate T cells strongly and increase the process of production and release of cytokines, and secretion of IgE from B cells, which in turn directly affects proinflammatory cells such as eosinophils, both in their tissues infiltration and functions.
Methods: The samples are collected from patients referring to ENT clinic in Rasoul Akram training Hospital in Tehran after thorough clinical and paraclinical examinations. For control group the samples collected from patients undergoing rhinoplasty. All the samples kept frozen and sent to immunology lab. The DNA of the excised tissues extracted and amplified by using the superantigens specific primers and PCR product detected by gel electrophoresis. The date analyzed by using mean and SD and χ2 analytical tools. 
Results: Fifteen healthy individuals, 25 patients with rhinosinusitis and 24 with polyposis entered this trial. Group A Streptococcus toxin detection was significantly more frequent in those with nasal polyp and rhinosinusitis compared to healthy individuals (P=0.001 and 0.005, respectively), but the results were almost the same for those with nasal polyp and rhinosinusitis (P=0.4).
Conclusion: Streptococci may play an important role in induction or clinical exacerbation of polyposis and group A Streptococcus pyogenes exotoxin (SPEs) with superantigenic effects may have a crucial role in etiology and pathogenesis of polyps with or without rhinosinusitis. It is postulated that, T cells polyclonal activation by SPEs may cause recruitment of inflammatory cells in nasal mucosa. These inflammatory cells include IgE producing B cells laeding to allergic and inflammatory reactions in NP.