Lungworms of the genus Troglostrongylus (Strongylida: Crenosomatidae): Neglected parasites for domestic cats

Feline lungworms belonging to the Troglostrongylus genus have been neglected for a long time. However, recent reports of Troglostrongylus brevior and Troglostrongylus subcrenatus in domestic cats have stimulated the interest of the scientific community on these lungworms. Troglostrongylus spp. have an indirect life cycle, which overlaps that of the better known Aelurostrongylus abstrusus. Nonetheless, adult worms of both genera have a distinct morphology and localization within the respiratory system of definitive hosts and, potentially, a different epidemiology and pathogenicity. As copromicroscopy has a low specificity for metastrongyloids due to the similarities of first-stage larvae, specific morphometrical keys and/or PCR diagnostic tools are advocated. Accordingly, more clinical studies and necropsy data are needed to elucidate the impact of Troglostrongylus spp. on the health of domestic cats. This article reviews current information on Troglostrongylus spp. as well as data on their occurrence in Europe and reports specific key morphological characters for the identification of adults and larvae, which is important to refine their diagnosis and for a better understanding of the feline lungworm infections.