Endocrine Abstracts

Introduction: In patients with severe, unexplained osteoporosis accompanied by normal calcium and elevated parathyroid hormone (PTH), normocalcemic primary hyperparathyroidism (NHPT) should be considered after excluding secondary hyperparathyroidism (SHPT)¹. This case underscores the diagnostic challenges of NHPT, particularly given frequent occurrence of small and multiple adenomas^1,2 and consequences of delayed parathyroidectomy, leading to multiple fractures, misdiagnosis of fibromyalgia, and complications from bisphosphonate treatment.

Patient Case: Results A 69-year-old woman presented with persistent bone pain and 20 years of worsening osteoporosis, complicated by multiple fractures. Her treatments included Hormonal Replacement Therapy at age 49, discontinued due to weight gain, along with calcichew-D3 and oral bisphosphonates, causing gastrointestinal discomfort due to hiatus hernia, hence switched to IV zoledronate. Between 2004 and 2019, she experienced a bimalleolar, tibia and fibula, pubic ramus and anterior acetabulum fracture. She has stable Chronic Kidney Disease Stage 3. Her chronic pain was diagnosed as fibromyalgia, a condition with higher prevalence in NHPT patients³. She received SSRIs, increasing the risk of bone loss and fractures⁴. She also has temporomandibular joint dysfunction; a condition associated with elevated PTH⁵. Despite having severe osteoporosis, she underwent contraindicated chiropractic spinal manipulation therapy (SMT)⁶. In 2024, NHPT was suspected due to persistently elevated PTH levels despite corrected vitamin D (Table 1). Urinary studies showed calcium-creatinine ratio = 0.028 and normal 24-hour urinary calcium of 5.9 mmol/day, excluding familial hypocalciuric hypercalcemia. This makes NHPT the most likely diagnosis. Imaging suggested potential thyroid asymmetry, but no clear parathyroidadenoma was confirmed - hence the patient is booked for 4D-CT.

References: 1. Leslie & Levine, 2024. 2. Trinh et al, 2018. 3. Costa et al, 2016. 4. Ferguson, 2001. 5. Demir & Ersoz, 2019. 6. Chu et al, 2023.