Endocrine Abstracts

Introduction: Lactation-related osteoporosis is a very rare entity, usually diagnosed with one or more fractures, during the early postpartum period. Due to the rarity of this condition, no consensus still exists with regard to thetype and optimal duration of treatment.

Case presentation: A 39-year old Caucasian female was presented at the outpatient clinic in December 2016 for evaluation and management of severely low bone mineral density (BMD) and multiple vertebral low energy fractures at the 5^thto 7^th(T5-T7) and 10^thto 12^ththoracic vertebrae (T10-T12). These fractures were diagnosed on occasion of severe back pain, following a weight-bearing activity, seven months after delivery. BMD assessed by dual-energy X-ray absorptiometry was markedly low, with absolute values of 0.783 g/cm² (T-score: −3.3, Z-score: −3.9) at lumbar spine (LS), 0.755 g/cm²(T-score: −1.9, Z-score: −2.1) at femoral neck (FN) and 0.709 g/cm²(T-score −2.4. Z-score: −2.7) at total hip (TH). Evaluation for causes of secondary osteoporosis (such as hyperthyroidism, hyperparathyroidism, celiac disease, hypercalciuria, renal or liver dysfunction) was negative, except for vitamin D deficiency (25-hydroxy-vitamin D concentrations: 12 ng/ml). Taking into account the patient’s reproductive status and the unknown effect of bisphosphonates on fetal growth in future pregnancies (due to their long retention to bone), teriparatide was initiated (daily injections of 20 μg for 24 months). Cholecalciferol was also administered, at weekly doses of 50.000 IU for eight weeks, followed by a daily dose of 1000 IU combined with calcium carbonate (600 mg/daily). The patient reported significant relief in musculoskeletal symptomatology from the first 2–3 weeks of teriparatide treatment. BMD showed an increase of 13.1%, 7% and 11.5% in LS, FN and TH at 12 months and 19.1%, 15.7% and 16.5%, at 24 months, respectively. At the end of therapy, T- and Z-scores at LS, FN and TH were −2.1 and −2.3, −0.9 and −1, −1.4 and −1.6, respectively. Teriparatide was well-tolerated and the patient returned to her daily activities during the first 3–4 months of therapy. Except for a new vertebral fracture affecting the 9^ththoracic vertebra at 12 months assessment, magnetic resonance imaging showed significant improvement in all fractured verterbral bodies at 12 and 24 months.

Conclusions: Teriparatide appears a quite effective and safe option in cases of lactation-associated osteoporosis, leading to a significant increase in both spinal and hip BMD. However, more data are needed to establish the optimal management and follow-up of these patients.