Crenosoma vulpis infection in a four-month old puppy

Here we report the case of a diagnostic and treatment challenge in a four-month old dog from England, presented with one-month history of unproductive cough. Antigen blood test for Angiostrongylus vasorum infection was negative. Thoracic radiographs revealed a generalised bronchointerstitial pattern and bronchoscopy showed moving nematodes in the mucus of the bronchial wall. Additionally, Baermann technique revealed a high burden of larvae per gram of faeces. Morphological and molecular analyses confirmed that they were first stage larvae of Crenosoma vulpis. The infection was firstly treated with a spot-on solution containing 10% imidacloprid + 2.5% moxidectin, but the dog was still positive after 13 days. Therefore, a seven-day course of fenbendazole was prescribed. This represents one of the youngest dogs ever reported naturally infected by C. vulpis. The scant number of reported cases of crenosomosis has led practitioners to consider it as a rare parasitic disease in dogs, delaying a correct and targeted on-time diagnosis. Further studies are needed to perceive the real prevalence of this lungworm and to understand if it is a rare parasite or just rarely diagnosed.