Ectopic Mineralisation
- Also called heterotopic mineralisation (calcification)
- Deposition of calcium phosphate, silicate and other in unusual locations
- Contrast with ectopic ossification
- Can be
- Idiopathic
- E.g. primary tumoral calcinosis (see below)
- Metastatic
- E.g. Associated with hypercalcaemia of uraemia and hypervitaminosis D
- Dystrophic
- E.g. due to repetitive trauma
- Idiopathic
- Calcinosis cutis
- Associated with hyperadrenocorticism, exposure to calcium chloride and wet concrete
- Also present in some normal poodles
- Calcinosis circumscripta (tumoral calcinosis)
- Usually single lesion in skin of extremities of dogs
- May occur in vertebral region and cause ataxia
- In horses mainly 2-4 years old at lateral stifle, not attached to skin
- May be the result of repetitive trauma (e.g. in supraspinatus tendon in hunting or working dogs)
- Grossly:
- Nodular masses about 1cm across or few cm more
- May ulcerate
- White, soft creamy or dry gritty on cutting
- Microscopically:
- Amorphous and granular mineralised areas
- Surrounded by connective tissue
- Granulomatous reaction is common
- Chronic lesions may contain metaplastic cartilage or bone