Marble bone disease is?
High-Yield Explanation
Osteopetrosis/ marble bone disease: * Bone within bone appearance on xray (increased bone density) * Due to mutation in CLCN7 gene. * Leads to defective bone resorption * C/F: Neurological problems present, Deafness, Macrocephaly , hepatosplenomegaly, Pancytopenia * Investigation: Low phosphorus and calcium levels with normal Vit D levels and elevated PTH.