Calcium Hydroxylapatite Deposition Disease in a Great Dane Puppy

Abstract

Abstract.A 10-week-old male Great Dane Puppy was presented for sudden onset tetraataxia and severe paresis of the front legs. Mineral deposits were detected radiographically, at gross postmortem examination, and light microscopically between the vertebral arches of multiple cervical and lumbar vertebrae. These deposits were associated with the interarchial ligaments (ligamentia interarcualia), along the interfaces of the synovium and articular cartilage of multiple cervical, thoracic, and lumbar facets, on the dorsal aspect of several thoracic intervertebral discs, and at the insertion of muscles at the lateral aspect of several cervical and thoracic vertebral bodies. The mineral deposits were associated with a granulomatous inflammation and synovial fibrocartilaginous metaplasia and proliferation, which was focally exuberant. X-ray diffraction analyses of the mineral deposits revealed calcium hydroxylapatite as the major component. The clinical signs in this puppy were due to focal compression of the spinal cord by marked extraarticular ligament-associated fibrocartilaginous proliferation.Key words: Calcium hydroxyapatite deposition disease; dogs; Great Dane; spine.In Great Dane puppies with paraplegia, calcium phosphate deposition disease has been reported in multiple diarthrodial joints of the appendicular and axial skeleton. 12 Here, we present a case of calcium hydroxylapatite deposition disease in a Great Dane puppy that was limited to the axial skeleton and included marked fibrocartilaginous proliferation, resulting in compression of the spinal cord.A 10-week-old male Great Dane dog, weighing about 7 kg, presented to the Veterinary Teaching Hospital of the Ohio State University for a 2-day history of progressive weakness. The puppy had been fed puppy food. On physical examination, the puppy appeared slightly depressed and was tetraataxic with severe bilateral paresis of both forelimbs, although the dog could support weight with both hind limbs. Conscious proprioception was not perceived in either forelimb and was decreased bilaterally in the hind limbs. Cranial nerve reflexes were normal. Flexor reflexes were decreased in the forelimbs but normal in the hind limbs. All forelimb segmental spinal reflexes were absent bilaterally. Patellar reflexes were increased, as were clonus and anterior tibial reflexes. The puppy was consistently pained by palpation of the cervical vertebrae and lateral and dorsoventral movement of the neck. A C1-C5 transverse myelopathy was suspected, based on the clinical signs and results of neurologic examination.Complete blood count revealed a mild nonregenerative anemia (packed cell volume ϭ 27.1%). No abnormalities were noted on the leukogram or platelet count. In the serum biochemical profile, all parameters investigated, including total calcium (10.3 mg/dl), ionized calcium (5.68 mg/dl), and phosphorus (5.7 mg/dl), were within normal limits. Survey radiographs of the vertebral column revealed irregular mineralization in the area of the intervertebral facets throughout the cervi...

Imaging Diagnosis: Multiple Cartilaginous Exostoses and Calcinosis Circumscripta Occurring Simultaneously in the Cervical Spine of a Dog

“…3,4,[11][12][13][14] Characteristic histopathology findings of calcinosis circumscripta include ectopic deposition of calcium salts in soft tissues, which appear as multifocal areas of mineralization, characterized by granular, basophilic material surrounded by macrophages and large multinucleate cells. 1,[15][16][17][18][19][20][21] Histologic findings in this patient showed convincing evidence that the mass involving C1 and C2 was consistent with multiple cartilaginous exostoses and calcinosis circumscripta.…”

“…It manifests as solitary or multiple masses consisting of calcium deposits that were reported to occur in periarticular soft tissues, subcutaneous tissues, under the tongue or, rarely, in the intestines. 1,[15][16][17][18][19][20][21] Calcinosis circumscripta is described radiographically as an irregularly marginated, mineralized mass (or masses), with no invasion of regional bones. [15][16][17][18][19][20] There are three main forms of calcinosis circumscripta: metastatic, dystrophic, and idiopathic.…”

“…1,[15][16][17][18][19][20][21] Calcinosis circumscripta is described radiographically as an irregularly marginated, mineralized mass (or masses), with no invasion of regional bones. [15][16][17][18][19][20] There are three main forms of calcinosis circumscripta: metastatic, dystrophic, and idiopathic. 1,15,16 The metastatic form occurs secondary to a derangement in calcium and/or phosphorus homeostasis.…”

Calcinosis Circumscripta in the Dog: A Retrospective Pathological Study

“…In the present study, two German Shepherd dogs each had approximately 3 cm diameter masses on right side of cervical vertebrate (C3–C4) without any underlying disease. A syndrome of calcium phosphate or hydroxylapatite deposition has been reported in young puppies of some breeds, especially Great Danes (Woodard et al., 1982; Marks et al., 1991; Palmer, 1993; Short and Jardine, 1993; Wunschmann et al., 2000). These cases showed signs of paraplegia, incoordination, pathologic spondylolisthesis and mineral deposition within vertebral canal and seem distinct from the paravertebral lesions seen in this study.…”

“…These cases showed signs of paraplegia, incoordination, pathologic spondylolisthesis and mineral deposition within vertebral canal and seem distinct from the paravertebral lesions seen in this study. The early onset of disease and equal sex distribution suggested a congenital or hereditary malformation (Flo and Tvedten, 1975; Woodard et al., 1982; Palmer, 1993; Wunschmann et al., 2000). A hereditary form of the human disease, characterized by early onset and higher familial incidence has been reported to be linked to a point mutation in the type II protocollagen gene (Basualo et al., 1993).…”