Clinical, laboratory, and ultrasonographic insights into Platynosomum fastosum infection in domestic cats: Diagnostic challenges and hepatobiliary implications.

Platynosomiasis is a hepatobiliary disease that primarily affects cats, caused by the trematode Platynosomum fastosum. In this context, this study aims to describe the main clinical, laboratory, and ultrasonographic findings of domestic cats naturally infected by P. fastosum. Six cats treated at the Veterinary Teaching Hospital (HV) of São Paulo State University (UNESP) in Botucatu, São Paulo, Brazil, with a coproparasitological diagnosis positive for P. fastosum were selected for this study. The following parameters were analyzed: clinical signs, complete blood count, serum biochemistry, and ultrasonographic changes. Clinical signs observed included jaundice, apathy, dehydration, and gastrointestinal symptoms such as emesis and constipation. Hematological analyses revealed normal ranges for most variables, except evidence of monocytosis. One cat exhibited leucocytosis associated with neutrophilia, eosinophilia, and monocytosis. Biochemical profiles indicated significantly high liver enzymes levels: alanine transaminase (mean 331 ± 305.3 UI/L), aspartate transaminase (mean 181.8 ± 98.9 UI/L), alkaline phosphatase (mean 260.8 ± 270.4 UI/L), and gamma-glutamyl transferase (mean 14.98 ± 11.52 UI/L). Ultrasonographic findings included hepatomegaly, gallbladder wall thickening, bile duct dilation, and increased pancreatic dimensions with reduced echogenicity, indicating possible cholangitis and pancreatitis, respectively. The elevated liver enzyme levels, clinical signs of jaundice, and ultrasonographic abnormalities are consistent with liver damage and potential cholangitis and pancreatitis due to Platynosomum fastosum infection. These findings highlight the need for targeted diagnostics that should support therapeutic interventions for felines suffering from platynosomiasis.