Dr Quynh Truong1, Dr Nirjhar Nandi, Dr Ruveena Kaur
1Cairns Hospital
Biography:
Dr Quynh Truong is an Obstetric Medicine Advanced Trainee at Cairns Hospital in Queensland Australia with an interest in Endocrinology.
Abstract:
Background: Osteogenesis Imperfecta (OI) is a rare skeletal dysplasia characterized by low bone mass, skeletal fragility and recurrent fractures(1,2). During pregnancy, OI is associated with an increased risk of maternal fracture and neonatal low birth weight(3,4). Approximately 90% of the genetic mutations in OI affect the type 1 collagen genes, COL1A1 or COL1A2(1,2).
Case Presentation: A 32-year-old woman in her first ongoing pregnancy sustained a minimal trauma patella fracture requiring fixation at 24 weeks gestation. Two months later, she developed hip pain while non-weight-bearing and was found to have a subcapital neck of femur fracture. She underwent a total hip joint replacement and was referred to endocrinology.
The patient reported multiple fractures from childhood to late adolescence, with some fractures associated with minimal trauma. She developed conductive hearing loss at age 30, with radiologic findings of bilateral severe otosclerosis. The patient had a history of poor dentition and was of short stature relative to other family members. Examination was relevant for blue sclera.
A bone mineral density (BMD) performed while the patient was breastfeeding demonstrated Z scores at the lumbar spine and femoral neck of -3.2 and –2.1 respectively. Her BMD improved following completion of breastfeeding, which would support the transient nature of pregnancy associated osteoporosis. Due to her presentation, she was investigated for dual pathology with genetic testing. This detected a COL1A1 (c.471+5G) variant of unknown significance, reported once prior in the literature(5). The patient is undergoing further testing to assess if this is a de novo mutation, which can have implications for her children.
This paper reviews the investigations and differential diagnosis to consider in a patient presenting with fracture in pregnancy. To our knowledge, this is the first reported case of dual pathology with pregnancy associated osteoporosis on a background of probable Osteogenesis Imperfecta.
Keywords
Osteogenesis imperfecta, osteoporosis, fracture
References
1. Cundy T. Recent advances in osteogenesis imperfecta. Calcif Tissue Int. 2012 Jun;90(6):439–49.
2. Ralston SH, Gaston MS. Management of Osteogenesis Imperfecta. Frontiers in Endocrinology [Internet]. 2020;10. Available from: https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2019.00924
3. Rao R, Cuthbertson D, Nagamani SCS, Sutton VR, Lee BH, Krischer J, et al. Pregnancy in women with osteogenesis imperfecta: pregnancy characteristics, maternal, and neonatal outcomes. Am J Obstet Gynecol MFM. 2021 Jul;3(4):100362.
4. Chamunyonga, F., Masendeke, K.L. & Mateveke, B. Osteogenesis imperfecta and pregnancy: a case report. J Med Case Reports 13, 363 (2019) [Internet]. Available from: https://doi.org/10.1186/s13256-019-2296-0.
5. Clin Var [Internet]. National Library of Medicine; Available from: https://www.ncbi.nlm.nih.gov/clinvar/variation/1346489/