Abstract
Background: Paget's disease of bone (PDB) is the second most frequent metabolic bone disease affecting about 3 percent of the Caucasian population older than 55 years. Its etiopathogenesis is unknown. While viral agents like measles and respiratory syncytial virus has been proposed, the role of genetic susceptibility loci such as SQSTM1/p62 gene mutations have been confirmed. A new inhibitory mechanism against osteoprotegerin (OPG) via autoantibodies has been revealed in a patient with occult celiac disease (CD) with a phenotype similar to juvenile Paget's disease, which suggests an immunological mechanism for Paget's disease-like disorders other than genetic causes. But there is no report in the literature addressing the shared immunological mechanisms underlying classic PDB, CD and psoriasis.
Case Presentation: Herein, the case of a 50-year-old Caucasian man being reported with progressive bilateral hearing loss. The patient had a history of total blindness which had developed shortly after a cranial osteotomy for optic nerve decompression without any specific diagnosis 15 years ago. He had also been suffering chronic psoriasis vulgaris. Because of his enlarged skull, a diagnosis of bone Paget's disease was suspected and plain radiographs revealed a polyostotic Paget's disease with characteristic radiologic signs. In searching for his refractory constipation causes, an elevated level of tissue transglutaminase IgA (tTG IgA) antibody was demonstrated. Alendronate sodium 40 mg daily was started and a gluten-free diet was recommended to him but he was not adherent to the treatments and lost to follow-up.
Conclusion: This case further supports the idea of considering PDB as an osteoimmunologic disorder, like psoriasis and CD, because of similar biochemical features, including elevated levels of Cytokines such as interleukin-6 and tumor necrosis factor- α as well as bone resorption markers such as OPG and urinary deoxypyridinoline. So, the treatment of Paget’s disease of the bone may benefit from progresses in osteoimmunology-targeted therapies. Also a probable causal relationship between PDB and CD either by production of neutralizing antibodies in CD against OPG or by inducing PDB in genetically susceptible patients through oxidative stress, has been postulated here.
