Background: Staphylococcal superantigens (SAg's) may have some role in otitis media with effusion (OME). The aim of this study was the search of staphylococcal SAg's in middle ear effusion of children with OME. 
Methods: This cross sectional-analytic study was done in ENT & pediatric wards upon 64 children with otitis media with effusion (OME) between 1-15 years, (mean age=7.42+4 years) of Rasoul Akram University Hospital, Tehran, Iran in 2009-2011. Fifty six percent (36) of cases were male, 43.8% (28) were female. Staphylococcal SAg's; Toxic Shock Syndrome Toxin-1 (TSST-1), Staphylococcal enterotoxin A, B, C, D (Enzyme immune assay, AB Cam, USA) were detected in middle ear effusion samples after conventional culture.
Results: None type of SAg's found in 39% of OME cases, enterotoxin B found in: 22%; enterotoxin A: 17%, enterotoxin C: 15.6%, enterotoxin D: 12.5%, Toxic Shock Syndrome Toxin-1 (TSST-1): 7.8% Mean age of cases with positive TSST-1, enterotoxin A, B, C, and D was: 1, 5, 8.6, 9.6 and 9.6 years respectively. Positive TSST had no agreement with positive enterotoxin A and C but had weak agreement with type B and D. Mean age of cases with positive TSST was one years which had significant difference with (7.9 years) in cases with negative TSST test (P<0.0001).
Conclusion: At least one or more type of staphylococcal toxins had found in middle ear effusion of 70% of OME cases with negative culture for Staphylococcus aureus. Even in culture negative cases, staphylococcal toxins might have some immunologic role in middle ear effusion forming. Finding the SAg's (at least one type) are important for treatment of immunosuppressive or corticosteroid in cases with resistant OME.