Urinary bladder worm infection is relatively uncommon in pet dogs and cats in the Americas. This report describes the diagnosis of lower urinary tract infection by Pearsonema plica in two asymptomatic dogs and P. feliscati in a cat with lower urinary tract clinical signs diagnosed between 2002 and 2015, and the first report of this type of parasitism in domestic small animals in Mexico at an altitude above 2600 m above sea level. The studied cases demonstrate the need to consider a urinary bladder worm infection in domestic small animals, both stray animals and those with controlled access to the streets. Although a definitive host as foxes does not exist among the urban wildlife in cities of the Americas, stray dogs and cats should be considered as potential reservoir hosts of Pearsonema, which requires future epidemiological studies in these populations.
Keywords: Cat; Dog; México; Pearsonema feliscati; Pearsonema plica; Urinary bladder worm.