[Bacterial infections in chronic otitis media--usefulness of molecular diagnostics based on PCR method].

Infections in chronic otitis media (COM) are common, and identification of their pathogen is difficult, what is proven by high rate of negative results of bacteriological examinations. This fact may be explained by two factors: it is difficult to obtain a reliable material for culture and classic methods of bacteriological cultures may be of low sensitivity. Amplification of bacterial DNA in PCR is an examination, that leads to a higher effectiveness and sensitivity of bacteriological tests. The authors present material of 53 patients with COM, previously untreated, in which bacteriological examinations by classic and molecular PCR method were performed. The results of both methods were compared. In classic method the presence of pathogens was observed in 46 of 53 cases (86.8%). The most often isolated bacteria were Pseudomonas aeruginosa (52.8% of the cases), Staphylococcus aureus (15.1%), Peptostreptococcus sp. and Fusobacterium sp. (11.3% of the cases each) and Proteus mirabilis (7.5%). In 7 cases (13.2%) bacteriological results were negative. Using molecular diagnostic of PCR, the presence of Pseudomonas aeruginosa was observed in 42 cases (79.2%). Isolated strains of P. aeruginosa were epidemiologically unrelated (93.7% of isolates), what was proven in PCR-finger-printing technique. The authors stated that predominant aerobes pathogens in COM are P. aeruginosa and S. aureus and the PCR technique for identification of bacterial DNA presence is very sensitive and allows to precipitate diagnostics of patients with COM. Combination of classical bacteriological tests with PCR technique may be very helpful in estimation bacteriological condition of patients with COM.