Sickle cell disease with osteogenesis imperfecta.

A 16 yr old female presented with generalized weakness and easy fatigability since 2 months. Her medical history included that she had sickle cell disease (ss pattern) on regular treatment. She denied smoking and consumption of alcohol. She had adequate calcium intake and her menstrual history was non-contributory. History of right tibial diaphysial fracture 1 year back followed by refracture at the same site 6 months later. On examination patient was 146 cm tall & weighed 48 kg. She had pallor, blue-grey sclera,scar mark of previous operation on right leg. Her mother and two maternal aunts also had blue-gray sclera. She had normal dentition and other systems were normal. Radiological screening showed diffuse osteopenia of all visualized skeleton, biconcave vertebral bodies in lumbar spine, Old healed fracture of right tibial diaphysis with intra-medullary nail in situ, wormian bones seen along the lambdoid suture, old healed fracture with sclerosis noted involving diaphysis of first metatarsal. Secondary causes of osteoporosis were ruled out. Skeletal involvement is sickle cell disease is usually in the form of avascular necrosis, dactylitis, joint effusions or osteomyelitis however osteoporosis and long bone fractures are not known in sickle cell disease. Owing to high index of suspicion a diagnosis of osteogenesis imperfecta was pursued, since the patient presented at 16 years age with relatively minor symptoms type 1A osteogenesis imperfecta (mildest form) was established. Systemic screening for disease complications included osteopontogram, audiogram and consultation with ophthalmologist and geneticist. Therapy with calcium and vit D was initiated and an in depth discussion regarding biphosphonates was pursued. Anaemia was corrected with blood transfusion and treatment of sickle cell disease was continued. Family screening was offered. Fractures particularly adults older than 45 are associated with osteoporosis. This case illustrates the importance of family history, fracture history and clinical correlation when assessing patients with osteoporosis. Mild OI most often presents after infancy and should be considered whenever children or adults have recurrent fractures. Early diagnosis of this disease by family physicians will enable initiation of therapy as well as patients education regarding management of modifiable risk factors linked with osteoporosis (e.g. diet, smoking, alcohol). Genetic counseling and family screening could also be offered.