RESUMEN
Peritoneal larval cestodiasis (PLC) was incidentally identified in an adult female mixed-breed dog by explorative celiotomy done in response to abnormal blood values found during a routine work-up in preparation for an ovariohysterectomy. Ten days after ovariohysterectomy, treatment with fenbendazole began (50mg/kg, per os, every 12h, for 21 days). Two weeks after the end of treatment, samples of peritoneal fluid were obtained by paracentesis and examined. Motile peritoneal tetrathyridia were still evident. Fenbendazole was discontinued. After 10 days of withdrawal from fenbendazole, the dog was treated with a subcutaneous administration of injectable praziquantel (5mg/kg). The administration was repeated after a 15 days interval. Two weeks after the second administration, samples of peritoneal fluid were obtained again by paracentesis. Motile peritoneal tetrathyridia were not detected. Fourteen months after the last administration of praziquantel, the dog remained still free of peritoneal tetrathyridia as determined by abdominal ecography. Therefore, praziquantel was effective to eliminate peritoneal tetrathyridia definitely. Practitioners should be aware of PLC in order to early recognize this condition in case of incidental finding and implement adequate therapy as soon as possible.