[Peculiarities of fungal and bacterial microorganisms persistence in the structure of fungal balls of paranasal sinuses].

A total of 148 samples were obtained from patients histologically diagnosed with fungal balls. Microscopic evaluation of the specimens stained according to the Gram method, Gomori-Grocott method and PAS-reaction method, revealed phase changes in the fungal balls conditioned by their different life cycles: the areas of young, mature and degenerating mycelium were detected. Degeneration lead to detritus formation. Detritus areas contained accumulated bacterial colonies. The cultural study of the fungal balls removed from paranasal sinuses, showed fungi growth in 17.6% of cases, while the pathomorphological study confirmed presence of fungi in every investigated sample. Aerobic and anaerobic microbiota of the sinuses contents was represented by multi-agent bacterial and fungal-bacterial associations. Statistical analysis of contingency between culture-positive rate of fungi and different bacteria detected in clinical samples from fungal balls revealed inhibitory influence of Pseudomonas aeruginosa on fungi growth, which might be a reasons of their low isolation rate. Supposedly in some cases the fungal balls consisted of dead fungi, or the sampling was done in the area of the fungal balls degeneration, which might also account for the low sensibility of the cultural method.