Local production of Aspergillus fumigatus specific immunoglobulin E in nasal polyps.

BACKGROUND

Aspergillus spp. play a significant role in the etiology of immunoglobulin (Ig)E mediated allergic fungal sinusitis (AFS). It is unclear whether Aspergillus spp. are also involved in nasal polyps without the characteristic clinical features of AFS.

OBJECTIVES

The frequency of Aspergillus spp. and Aspergillus-specific IgE in nasal lavages and serum of patients with severe nasal polyps (n = 33) without clinical features of AFS should be investigated.

STUDY

DESIGN

Prospective study.

METHODS

An aliquot of nasal lavage fluid was treated with dithiothreitol and examined for Aspergillus fumigatus by culture and an Aspergillus-specific polymerase chain reaction (PCR) assay. An additional aliquot of nasal fluid and serum of the same patient were tested for specific IgE (Unicap, Pharmacia, Freiburg, Germany) to recombinant Aspergillus fumigatus allergen (rAspf) 1 to 6.

RESULTS

All patients had negative skin prick tests for Aspergillus fumigatus. Four of 33 (12%) lavage samples were positive for Aspergillus spp. by PCR. In one of these samples, rAspf-specific IgE was detected but none in the serum. Nasal lavage and serum samples of the remaining 29 patients were negative for rAspf-specific IgE.

CONCLUSIONS

Aspergillus spp. detection is rare in patients with severe nasal polyps without characteristic clinical features of AFS. Specific IgE in nasal secretions may be elevated in patients with negative skin prick tests and serum IgE. In these cases, immunologic mechanisms similar to AFS may be involved. Fungal etiology has been proposed to underlie severe nasal polyps in general. However, Aspergillus spp. seem not to play a significant role.