Osteopoikilosis: A rare cause of bone pain

Background: Osteopoikilosis (OPK) is a rare inherited condition of the bones, transmitted as an autosomal dominant trait characterized by numerous hyperostotic areas that tend to localize in periarticular osseous regions. It is usually asymptomatic and is often diagnosed incidentally during x-rays made by other reasons. We present a case of 34-year-old man suffering from polyarthralgia and low back pain. Case presentation: A 34-year-old male patient, smoking 40 packs yearly and alcoholic was referred to our department of rheumatology, complaining of polyarthralgia which started 3 years ago and involving large and small joints. He reported the presence of pelvic pain mostly located at both hip joints and in the two ankles. On radiologic examination, numerous, symmetric, well defined, sclerotic lesions were identified on shoulder, wrist, ankles, pelvis, and on spine. The size of the lesions varied from 2 to 9 millimeters. These spots were located on spongious bone tissue, and in the inner bone cortex located bilaterally in the epiphyses and metaphyses. We concluded the diagnosis of OPK. His mother was found to have the same lesions without any symptoms. Conclusion: OPK may be an isolated finding or associated with other pathologies, e.g. skin manifestations, rheumatic and/or skeletal disorders. The main differential diagnosis is osteoblastic metastasis.