PAINFUL VERTEBRAL FRACTURES DURING PREGNANCY: BE AWARE OF A POTENTIAL UNDERLYING GENETIC CAUSE

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 234-256-Bone & Calcium Metabolism: Clinical Trials & Case Series
Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-235
Ling Oei*1, Natalia Campos1, Marleen EH Simon2 and Maria Carola Zillikens1
1Erasmus MC, Rotterdam, Netherlands, 2Erasmus MC
Background: During pregnancy, the baby growing in its mother’s womb needs calcium to develop its skeleton. Maternal osteoporosis has been attributed to pregnancy in some cases.

Presenting problem: A 27-year old woman in the 7th month of her first pregnancy complained of mid-thoracic back pain after lifting a non-heavy object. The pain remained intermittently with differing intensity and was attributed to her pregnancy. After delivery of a healthy child, this back pain prevented her from lifting her baby. She received physiotherapy without any effect on the pain. Her past medical history was uneventful except for severely reduced vision in her left eye since birth. She had never experienced a fracture. She used three dairy products per day and no medication. Family history revealed that her maternal grandmother was known with osteoporosis at old age. Physical examination: height 1.58m (5'2"), weight 53 kg (117 lbs). No blue sclerae. Amblyopia of the left eye. No hyperlaxity of skin or joints. Laboratory examination including serum calcium, phosphate, alkaline phosphatase, creatinine, bCTX, 25-hydroxyvitamin D and TSH was normal. X-ray examination of the thoraco-lumbar spine showed end-plate compressions of multiple thoracic vertebrae (Th7,9,10 and 12). DXA-scanning showed severe osteoporosis (T-score L2-L4: - 5.7 SD, femur neck: - 3.9 SD). DNA analyses revealed two mutations in the LRP5 gene. Her mother, recently postmenopausal, also had osteoporosis on the DXA scan and was a heterozygous carrier of an LRP5 mutation. Her only sibling (brother) was treated with cabergoline for a microprolactinoma and had osteopenia on DXA; he was also carrier of an LRP5 mutation.

Clinical management: A diagnosis of osteoporosis pseudoglioma syndrome was made and the patient was treated with risedronate for 2.5 years. BMD and back pain improved. She stopped the use of bisphosponates 6 months before planning a second pregnancy.

Discussion: Genetic causes such as osteogenesis imperfecta or osteoporosis pseudoglioma syndrome may underlie maternal osteoporosis in some cases and should be ruled out. A genetic diagnosis has implications for the patient as well as his/her relatives. More studies into pregnancy-associated osteoporosis are desirable to support evidence-based advice regarding bisphonate administration preceding conception.

Nothing to Disclose: LO, NC, MES, MCZ

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm