Calvarial hyperostosis syndrome in a Dalmatian dog

Key clinical message: Calvarial hyperostosis syndrome is an uncommon and self-limiting disease affecting juvenile dogs. Only symptomatic treatment has been described, and diagnosis is based on clinical findings, imaging, and disease progression.

Abstract: This is the first reported case of calvarial hyperostosis syndrome in a Dalmatian dog. It is an uncommon osteoproliferative disease with diagnosis frequently based on clinical signs, imaging findings, and disease progression, with only symptomatic treatment described. Case describes a 5-month-old Dalmatian dog presented with a facial mass and difficulty eating. After imaging, mass was observed to be osteoproliferative, nonaggressive, and without affection of the temporomandibular joints and mandibles. Histology revealed an osseous-cartilaginous and proliferative lesion, together with scant amount of neutrophiles. Clinical improvement was observed after symptomatic treatment, and moderate lesion regression was observed in a CT reevaluation 6 months later.