Clinical diagnosis, ultrastructural study and antigenic characterization of platynosomum fastosum in cats

Abstract

Platynosomum fastosum is a cat liver fluke causing hepatobiliary diseases in cats. To evaluate the criterior to support the suspicion index for early disease detection during subclinical infection, the biochemical parameters composed of liver, pancreatic enzymes, tumor markers were evaluated in 14 P. fastosum naturally-infected cats. As a result, alanine transaminase (ALT) and gamma glutamyl transferase (GGT) were found elevated in 57.8% (8/14) of infected cats. For the diagnostic imaging, bile sediments were present in 85.7% (12/14) of infected cats in their gallbladders. Since the number of bile-derived P. fastosum eggs were significantly higher than that from fecal samples (p=0.001), percutaneous ultrasound-guided cholecystocentesis seemed to be promising to be implemented as a tool for final diagnosis. To establish the fundamental data on ultrastructural characteristics of P. fastosum adult and egg for further drug testing as no effective drug available, scanning electron microscope was used to reveal the tegumental surface in which it was covered with densely packed villous-like projections and papillae. Using transmission electron microscope, at least one type of tegumental cell was found producing 2 types of tegumental granules inside P. fastosum adult tegument. To develop serodiagnostic assay, antigenic components of P. fastosum were characterized and 3 immunogenic proteins (70kDa, 53kDa and 13kDa) were identified and the sequences were characterized.