Dear editor,

The article of Niederfuhr et al. entitled Staphylococcus aureus in nasal lavage and biopsy of patients with chronic rhinosinusitis (1) published in Allergy, October 2008, comes to the conclusion that there is no higher prevalence of S. aureus among chronic rhinosinusitis patients with (CRSwNP) or without nasal polyps vs control patients. They also conclude that S. aureus does not intensify the TH2 shift in CRSwNP patients. We do not share these conclusions for the following reasons.

First, there are various studies showing that colonization with S. aureus is more frequent in patients with CRS, more specifically with nasal polyps, either pre- or postoperatively compared with control patients (2–5). The authors of the article do fail to confirm this finding possibly because of the technique they used for sampling (nasal lavage), which does not specifically harvest the bacteria from the middle meatus, but instead from the whole nasal cavity and vestibulum.

Second, the authors could not regularly identify S. aureus in tissue using fluorescence in situ hybridization with the specific peptide nucleic acid probe (PNA-FISH). However, PNA-FISH has repeatedly demonstrated excellent sensitivity and specificity for the detection of S. aureus in blood (6) and of other bacteria (7) in different tissues. In addition, Lefmann et al. identified isolates of mycobacteria in paraffin embedded tissue sections (8). In our hands, this technique gives reliable results to identify S. aureus in the nasal mucosa (Fig. 1, unpublished data). We therefore believe that a technical mistake may account for the difference in observations.


Figure 1.  Nasal polyp tissue stained for S. aureus with PNA-FISH Kit (Cat. No. KT001, AdvanDX, Woburn, MA, USA). Zeiss axioplan epifluorescence microscope with a CCD camera (Sony IMAC-CCD S30) using a fluorescein isothiocyanate filter at 100 × under oil.

Download figure to PowerPoint

Third, the authors refer to some of our publications (1, 2), but seem to wrongly interpret them; they do not refer to a recent publication showing no difference in the superantigen production potential between germs from healthy people and nasal polyp patients (9); otherwise, they would not have expected a correlation between S. aureus presence and inflammatory parameters. Such changes are dependent on an immune reaction of the local TH2 cells to S. aureus superantigens (SAE). As described in previous studies, we refer to the presence of SAE-specific IgE antibodies as a marker of such reaction, which is associated with a significant increase in eosinophil-related inflammatory parameters such as IL-5 and ECP (2, 10, 11). Unfortunately, although taking a biopsy, the authors did not attempt to measure total and SAE-IgE in tissue homogenates.

Finally, the authors used nasal lavage for the measurement of cytokines and mediators of inflammation, hoping that concentrations in nasal secretions would reflect those in tissue. They confirmed that IL-5 and IgE were higher in CRSwNP compared with controls, but did not report a difference in ECP. However, the amplitude of concentrations of IgE and IL-5 is very small, so that differences between subgroups obviously would be difficult to uncover. The authors, as they comment themselves in their discussion, should better have used homogenates from mucosal tissue instead of nasal lavage.

In summary, the authors should have interpreted their results much more carefully and should have discussed the shortcomings in order to avoid wrong conclusions from their paper.


  1. Top of page
  2. References
  • 1
    Niederfuhr A, Kirsche H, Deutschle T, Poppert S, Riechelmann H, Wellinghausen N. Staphylococcus aureus in nasal lavage and biopsy of patients with chronic rhinosinusitis. Allergy 2008;63:13591367.
  • 2
    Van Zele T, Gevaert P, Watelet JB, Claeys G, Holtappels G, Claeys C et al. Staphylococcus aureus colonization and IgE antibody formation to enterotoxins is increased in nasal polyposis. J Allergy Clin Immunol 2004;114:981983.
  • 3
    Lin A, Busada NY. Staphylococcus aureus and endoscopic sinus surgery. Curr Opin Otolaryngol Head Neck Surg 2006;14:1922.
  • 4
    Araujo E, Dall C, Cantarelli V, Pereira A, Mariante AR. Microbiology of middle meatus in chronic rhinosinusitis. Braz J Otorhinolaryngol 2007;73:549555.
  • 5
    Ozcan M, Unal A, Aksaray S, Yalcin F, Akdeniz T. Correlation of middle meatus and ethmoid sinus microbiology in patients with chronic sinusitis. Rhinology 2002;40:2427.
  • 6
    Oliveira K, Procop GW, Wilson D, Coull J, Stender H. Rapid identification of Staphylococcus aureus directly from blood cultures by fluorescence in situ hybridization with peptide nucleic acid probes. J Clin Microbiol 2002;40:247251.
  • 7
    Perry-O’Keefe H, Rigby S, Oliveira K, Sorensen D, Stender H, Coull J et al. Identification of indicator microorganisms using a standardized PNA FISH method. J Microbiol Methods 2001;47:281292.
  • 8
    Lefmann M, Schweickert B, Buchholz P, Gobel UB, Ulrichs T, Seiler P et al. Evaluation of peptide nucleic acid-fluorescence in situ hybridization for identification of clinically relevant mycobacteria in clinical specimens and tissue sections. J Clin Microbiol 2006;44:37603767.
  • 9
    Van Zele T, Vaneechoutte M, Holtappels G, Gevaert P, Van Cauwenberge P, Bachert C. Detection of enterotoxin DNA in S aureus strains obtained from the middle meatus in controls and nasal polyp patients. Am J Rhinol 2008;22:223227.
  • 10
    Bachert C, Gevaert P, Holtappels G, Johansson SG, Van Cauwenberge P. Total and specific IgE in nasal polyps is related to local eosinophilic inflammation. J Allergy Clin Immunol 2001;107:607614.
  • 11
    Bachert C, Gevaert P, Zhang N, Van Zele T, Perez-Novo C. Role of staphylococcal superantigens in airway disease. Chem Immunol Allergy 2007;93:214236.