Crenosoma vulpis is a metastrongylid nematode that infects the bronchi, bronchioles, and trachea of wild and domestic canids and various other carnivores. It is endemic in the red fox population in the north-eastern parts of North America and in Europe, including Italy. Dogs are susceptible to infection with clinical signs consisting primarily in a chronic cough. The present paper reports-to the authors' knowledge-the first case of spontaneous C. vulpis infection in a dog in Italy. In addition, it also reports, for the first time, the use of the FLOTAC technique for C. vulpis diagnosis in canine fecal samples, with results compared to the following four standard copromicroscopic techniques: the Baermann technique, the McMaster technique, the simple flotation technique, and the Wisconsin technique. The results showed that the FLOTAC technique produced mean larvae per gram of feces greater than that produced by the other more widely used diagnostic tools. After the treatment of the C. vulpis infected dog with a single oral dose of 0.5mg/kg milbemycin oxime, the clinical signs resolved and the shedding of larvae ceased. In conclusion, the discovery of C. vulpis for the first time in a dog in Italy indicates that the fox lungworm should be considered in the differential diagnosis of respiratory disease in dogs; in addition, the findings of the comparison study showed that the FLOTAC technique may improve the ability to accurately diagnose canine lungworm infections.