Acanthamoeba keratitis: Increased sensitivity of the detection of parasites by modified cultivation procedure

The purpose of this study was to improve current methods for the detection of Acanthamoeba spp. in clinical samples. The sensitivity of parasite detec tion in filtered specimens was evaluated using samples containing different numbers of parasites. They were filtered through cellulose membranes and c ultivated on non-nutrient agar plates covered with Escherichia coli. The re covery of amoebae collected by filtration was compared with the cultivation of centrifuged samples. All samples containing 10 parasites per specimen a nd 65% of samples containing 2 parasites per specimen yielded positive cult ures after filtration, while the cultivation results after centrifugation w ere 8% and 0%, respectively. We conclude that significantly higher sensitiv ity of parasite detection can be obtained,vith samples processed br filtrat ion.