THU438 A Case Of Pregnancy Associated Osteoporosis

Abstract

Abstract Disclosure: S. Maradana: None. F. Iqbal: None. M. Safran: None. Background: Pregnancy associated osteoporosis (PAO) is a rare form of osteoporosis that is seen in late pregnancy and early post-partum period. Hip and vertebral body are most involved in PAO. Common clinical manifestation is back pain, and many patients suffer from vertebral fractures and kyphosis causing great physiologic burden and negative impact on quality of life. We report a case of PAO with good response to teriparatide. Clinical case: A 27-year-old female with no significant past medical history presented with severe acute back pain two months after delivery of her second child, whilst still breast feeding. Imaging studies demonstrated acute compression fractures of T12, L1, L2 and L3 vertebrae. She had regular monthly menstrual cycles prior to pregnancy with no previous history of fractures. Her pre pregnancy weight was 135 lbs and she had been physically active, while caring for her older son. Family history is notable for osteoporosis in multiple paternal aunts and maternal grandmother with no family history of fractures. There were no other identifiable risk factors. Evaluation for secondary causes of osteoporosis showed 25-OH vitamin D levels of 23 ng/mL (NL 30-100 ng/mL), TSH 1.72 uIU/mL (NL 0.28-3.8 uIU/mL), PTH 19 pg/mL (NL 14-64 pg/mL), calcium 9.7 mg/dL (NL 8.7-10.7 mg/dL), phosphorus 4 mg/dL (NL 2.5-4.5 mg/dL), tryptase 4 mcg/L (NL <11 mcg/L), alkaline phosphatase 111 U/L (NL 30-115 U/L) and 24-hour urine calcium 168 mg (NL 100-300 mg). Urine immune electrophoresis and serum immunofixation did not show any evidence of monoclonal gammopathy. DEXA scan showed low BMD with Z-score of −4.4 SD in lumbar spine -3.1 in femoral neck. She was diagnosed with PAO. She stopped breast feeding after the diagnosis. As the bone mineral density was very low, she was started on teriparatide along with calcium and vitamin D supplementation. One year after treatment initiation, her DEXA scan showed improved bone mineral density with Z-score of −3.5 in lumbar spine and −1.9 in femoral neck. Her osteoporosis is currently being managed with teriparatide with plan to continue for a total duration of 24 months. Conclusion: PAO is under-recognized and under-reported, with limited available evidence on the management. Spontaneous improvement in BMD is known to occur in 6-12 months after pregnancy and lactation have been completed, although, the addition of anti-resorptive treatment in this setting may result in superior BMD gain compared with calcium and vitamin D supplementation alone. Use of teriparatide has shown to have significant increase in BMD and help with pain relief in PAO. Teriparatide has helped with improving the BMD in our patient. Nevertheless, controlled trials are lacking, and the optimal timing of teriparatide use in these women remains uncertain. Presentation: Thursday, June 15, 2023