12609 Navigating The Therapeutic Challenge Of Post-surgical Hypoparathyroidism And Refractory Hypocalcemia

Abstract

Abstract Disclosure: D. Fawcett: None. A. Domingo: None. Introduction: Post-surgical hypoparathyroidism poses a challenge due to calcium metabolism disturbances, ranging from mild to life-threatening complications. Despite advancements, vigilant monitoring and tailored interventions are vital for optimizing outcomes. Refractory hypocalcemia, resistant to standard therapies, underscores the need for specialized care to prevent prolonged hospitalization and morbidity. Case description: A 68-year-old woman with a history of Graves' disease and parathyroid carcinoma underwent total thyroidectomy and parathyroidectomy in January 2024. She presented to the emergency department for the second time with a recurrence of bilateral hand and perioral paresthesias, along with numbness, tingling, and weakness throughout her body. Notably, she had a prior hospital admission with similar symptoms and was discharged on calcium carbonate, magnesium, calcitriol, and vitamin D3. Vital signs were not provided. Initial laboratory workup revealed a calcium level of 4.3, with corrected calcium at 5.8, and magnesium levels at 1.8, supplemented with magnesium oxide. A 24-hour urine calcium test, vitamin D, and malabsorptive workup for celiac disease were unremarkable. Immunoglobulin A was low; however, tissue transglutaminase IgA and anti-gliadin antibodies were negative. An electrocardiogram showed a normal sinus rhythm with QT prolongation to 570 ms. Despite resuming her home regimen, her calcium level remained low, prompting initiation of calcium infusion. Consultations with endocrinology and nephrology were made, necessitating close monitoring and uptitration of calcium and vitamin D supplements for achievement and maintenance of low normal calcium levels. High doses of 3g TID of calcium and calcitriol 2mcg PO TID allowed for symptom control and discharge with outpatient follow-up with endocrinology and nephrology. Conclusion: Supplemental therapy with calcium and vitamin D analogues is standard for managing post-surgical hypoparathyroidism. Early identification and adequate management prevent hypocalcemia-related complications, including tetany, seizures, and cardiovascular anomalies such as QTc prolongation, as seen in our patient, which can result in torsade de pointes. Multidisciplinary care alongside nephrology was paramount. Serum calcium should be maintained in the low normal range, and 24-hour urine calcium excretion should also be closely monitored. Daily hydrochlorothiazide can be used to prevent hypercalciuria. In recurrent cases, as in our patient, titration of calcium and vitamin D analogues is imperative. Long-term consequences, including renal dysfunction, osteoporosis, and increased cardiovascular risk, underscore the necessity for timely diagnosis and management. Presentation: 6/2/2024