Investigations on allergic fungal genesis of chronic rhinosinusitis

Abstract

The incidence of allergic fungal sinusitis (AFS) is estimated differently. The importance of hyphal findings in nasal mucus for initiation of chronic hyperplastic sinusitis is not proven. 124 patients with clinical signs and CT-scan findings of a chronic-hyperplastic rhinosinusitis were treated by functional endoscopic sinus surgery. During the operation a thick mucus was found in each patient. The mucus was isolated and investigated by histopathological analysis with special Grocott-stain and a culture for fungal growth was initiated. Furthermore the diagnostic for allergic reactions against fungus was done by prick- and RAST-tests. 21 patients had positive histopathological findings of fungus. In 10 cases fungal hyphae were found embedded in typical eosinophilic mucus. A positive allergic reaction against fungus was seen in 7 of these 10 patients. The culture results showed different pictures according to the isolated species, in 3 cases of the 10 AFS cases the culture was negative. The other 11 cases of 21 positive histological findings of fungus were cases of a fungus ball. The other 103 patients were without any sign for fungus in the HE- or Grocott-stain. A high incidence of AFS is not evident in group of chronic hyperplastic rhinosinusitis. The presence of eosinophilic "allergic" mucus is not the evidence for AFS. The inflammatory cascade leading to the clinical picture is a multifactorial event. The role of detectable fungus hyphae have to be estimated by further investigations.