A woman with brittle bones and blue sclerae

Case scenario

Tanya is 46 years old and attends her GP because she thinks she has fractured a rib during a coughing fit. She has fractured a rib once before. She has known osteoporosis. This was diagnosed three years ago; she was not perimenopausal at the time and was commenced on a low-dose oral contraceptive pill and has had annual bisphosphonate infusions since. There is no family history of osteoporosis and all investigations have shown no reversible cause. She is noted to have blue sclerae, which she says have been lifelong. Her current T-score is -3.0.

• What investigations should be arranged for this patient given her unusually early and severe osteoporosis?
• Blue sclerae are an unusual feature. Combined with early osteoporosis, does this fit into any specific category of osteogenesis imperfecta?
• What is the likelihood this patient’s condition is hereditary, and what investigations should be suggested for her teenage children (a boy and a girl)?
• Should Tanya’s medical management be changed?