Screening for staphylococcal superantigen genes shows no correlation with the presence or the severity of chronic rhinosinusitis and nasal polyposis.

BACKGROUND: Staphylococcus aureus secretes numerous exotoxins which may exhibit superantigenic properties. Whereas the virulence of several of them is well documented, their exact biological effects are not fully understood. Exotoxins may influence the immune and inflammatory state of various organs, including the sinonasal mucosa: their possible involvement in chronic rhinosinusitis has been suggested and is one of the main trends in current research. The aim of this study was to investigate whether the presence of any of the 22 currently known staphylococcal exotoxin genes could be correlated with chronic rhinosinusitis. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a prospective, multi-centred European study, analysing 93 Staphylococcus aureus positive swabs taken from the middle meatus of patients suffering from chronic rhinosinusitis, with or without nasal polyposis, and controls. Strains were systematically tested for the presence of the 22 currently known exotoxin genes and genotyped according to their agr groups. No direct correlation was observed between chronic rhinosinusitis, with or without nasal polyposis, and either agr groups or the presence of the most studied exotoxins genes (egc, sea, seb, pvl, exfoliatins or tsst-1). However, genes for enterotoxins P and Q were frequently observed in nasal polyposis for the first time, but absent in the control group. The number of exotoxin genes detected was not statistically different among the 3 patient groups. CONCLUSIONS/SIGNIFICANCE: Unlike many previous studies have been suggesting, we did not find any evident correlation between staphylococcal exotoxin genes and the presence or severity of chronic rhinosinusitis with or without nasal polyposis.

Evaluation of subjectivity in the interpretation of videonystagmography.

CONCLUSION: Subjectivity seems to play a definite role in the interpretation of the pendular test, but somewhat less for caloric testing, where pure visual analysis seems to be more reliable. Automated values provided by proof-tested software may be useful. OBJECTIVES: In some centers, the interpretation of videonystagmography is still based on direct visual analysis of recorded tracings. Our study addresses the importance of subjectivity in the interpretation of videonystagmographic readings. PATIENTS AND METHODS: Two experts (one junior and the other senior) were asked to interpret the same caloric and pendular tests on two different occasions, 3 months apart. Initial reading was performed without knowledge of the patient's history or the results of other neuro-otological tests. Three months later, interpretations were done with complete access to the patient's charts. The experts' answers were compared to the values provided by the computer software. RESULTS: For the pendular test, inter-expert agreement was poor. With knowledge of the patient's history, the expert's interpretations tended to coincide with the software's calculations. For the caloric test, interpretation was less variable.