Malignant Infantile Osteopetrosis.

Two main forms of osteopetrosis are recognized, a severe autosomal recessive form (MIM 259700) with an incidence of approximately 1 in 250,000 births and a mild autosomal dominant form (MIM166600) with an incidence of 1 in 20,000 births. Intrinsic disturbances of osteoclastic function due to mutations in genes encoding osteoclast-specific subunits of the vacuolar proton pump (TCIRG1, CLCN7) are found in most patients with recessive form. Mutations of CLCN7 are observed in dominant form of osteopetrosis .The recessive form of ostreopetrosis, i.e., malignant infantile osteopetrosis (MIOP) presents early in life with extreme sclerosis of the skeleton and reduction of marrow space. Signs/symptoms of MIOP appear as early as neonatal age. As there is defect in bone marrow children present with deficiency of red blood cells, white blood cells and platelets. There is extramedullary haemopoiesis, cranial nerve compressions and severe growth failure. The condition also presents with early and late onset neonatal sepsis and is often lethal in the first decade of life due to secondary infections. Treatment is mainly supportive. The only curative treatment is stem cell transplantation. This is a case report of a new-born who was admitted in nursery of Ayub Teaching Hospital initially with complains of neonatal jaundice and sepsis , and a second time with lower respiratory tract infection. Death was eventually due to sepsis. Workup led to diagnosis of Malignant infantile osteopetrosis.