Osteopetrosis, literally "stone bone", also known as marble bone disease or Albers-Schönberg disease, is an extremely rare inherited disorder whereby the bones harden, becoming denser, in contrast to more prevalent conditions like osteoporosis, in which the bones become less dense and more brittle, or osteomalacia, in which the bones soften. Osteopetrosis can cause bones to dissolve and break.It is one of the hereditary causes of osteosclerosis. It is considered to be the prototype of osteosclerosing dysplasias. The cause of the disease is understood to be malfunctioning osteoclasts and their inability to resorb bone. Although human osteopetrosis is a heterogeneous disorder encompassing different molecular lesions and a range of clinical features, all forms share a single pathogenic nexus in the osteoclast. The exact molecular defects or location of the mutations taking place are unknown. Osteopetrosis was first described in 1903, by German radiologist Albers-Schönberg. Signs and symptoms
Despite this excess bone formation, people with osteopetrosis tend to have bones that are more brittle than normal. Mild osteopetrosis may cause no symptoms, and present no problems.
However, new research shows that around 55% of cases involve a mutation in the CBP gene, further suggesting that this disease has its origins in mutation of the regulatory mechanisms of transcription (Izumi, 2016). Treatment
There is no existing treatment that reverses or cures RTS. There are, however, ways to manage and reduce symptoms for patients. Patients with RTS suffer from a diverse breadth of symptoms. These include cognitive-developmental impairment, heart abnormalities, delayed bone growth and skeletal abnormalities, auditory impairment, urinary tract abnormalities, including kidney problems, and dental and speech problems. Not every patient will suffer from all or multiple symptoms, and not every patient will experience the same symptoms, meaning they differ from patient to patient. Due to there being a wide range of symptoms, RTS patients are referred to specialists that focus on each specific symptom. There is not a specialist for RTS. For example, patients will go to an orthopedic surgeon and physical therapy for skeletal and growth abnormalities, like scoliosis but will go to a cardiologist if they suffer from heart abnormalities or a dentist if they suffer from dental abnormalities. Individuals suffering from cognitive developments usually are part of special education programs and speech therapy. The specialists the individuals go to match the symptoms the individuals have. Regular check-ups and monitoring are needed for cardiac, dental, auditory, and renal abnormalities. Genetic counseling is also recommended for affected individuals and their families.