SAT-LB71 Is Late Diagnosis of Postsurgical Hypoparathyroidism the Rule, Not the Exception?

Background The most prevalent etiology for hypoparathyroidism is postsurgical. In the literature, years or even decades of delay for the diagnosis have been reported, with sometimes extremely low calcium levels and dramatic clinical manifestations including heart failure and seizures requiring treatment in the emergency room or intensive care unit. Often,,typical“ hypocalcemic symptoms are absent in these patients. Methods In this retrospective Austrian single-center cohort at the Medical University of Graz, we identified patients with low parathyroid hormone concentration (<25 pg/ml) and hypocalcemia using the hospital information system during 2004 and 2014. The time between neck surgery and the first reported diagnosis of postsurgical hypoparathyroidism and/or available low calcium levels was collected. Results We identified a total of 119 patients treated between 2004 and 2014 at our institution. Most patients were women (78%), the average age was 61 ± 17 years. 12% had nonsurgical etiologies (ie. AIRE or 22q11 mutations), and 88% had postsurgical hypoparathyroidism (n=105). The median time between surgery and diagnosis of hypoparathyroidism was 5.5 years (range 0 -67 years). Only a third of all patients was diagnosed within the first year after surgery. Paresthesia and tetany were present in most patients at diagnosis, but in extreme hypocalcemia, other,,non-classic“ symptoms including severe heart failure, dyspnea and seizures appeared to be more prevalent. Conclusion Our data suggest that diagnosis of permanent postoperative hypoparathyroidism is often delayed, as in our Austrian retrospective cohort the time lag between surgery and diagnosis or onset of hypoparathyroidism was often years or even decades. Whether this is truly a delayed occurrence of the disease or a delayed diagnosis of a condition already present for years or a combination of both can not be answered with our data, but certainly merits more intense research in the future.