​Pathology - Osteopetrosis

​Pathology - Osteopetrosis 
abnormal bone resorption as a result of osteoclast activity dysfunction.
There are other varieties, such as a less severe autosomal dominant form and a deadly autosomal recessive variety.

Pathology 
Gross: Dense, thick bones; widened ends of bones (Erlenmeyer flask appearance).
Microscopic: Absence of hematopoietic marrow or trabeculae; persistence of primary spongiosa, calcified cartilage generated during endochondral bone formation.

Clinical Signs and Symptoms 
Multiple fractures; infections; hepatosplenomegaly (from extramedullary hematopoiesis); cranial nerve palsies (blindness, deafness, facial paralysis); and various neuropathies (from nerve compression brought on by restricted neural foramina).

Treatment 
corticosteroids and bone marrow transplantation as treatments.

A condition known as McCune-Albright syndrome affects young girls. Cafe-au-lait spots, small stature, early puberty (or other endocrine hyperfunctions like acromegaly or hyperthyroidism), and polyostotic fibrous dysplasia (fibrous replacement of medullary bone in various sites) are some of its manifestations.