Permanent hypoparathyroidism following SARS-CoV-2 infection: a case report with two-year follow-up and literature review.

Beyond its predominant respiratory involvement, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection has also been implicated in endocrine dysfunction. Hypocalcemia is common in Coronavirus Disease 2019 (COVID-19), yet the insufficient compensatory rise in parathyroid hormone (PTH) and its long-term outcomes remain poorly characterized. We describe a young adult Chinese woman with no history of neck surgery who developed severe symptomatic hypocalcemia shortly after acute SARS-CoV-2 infection. Laboratory evaluation revealed inappropriately low PTH levels with concomitant hyperphosphatemia, consistent with hypoparathyroidism (HypoPT). Although baseline calcium/PTH data prior to infection were unavailable, the regular calcium and vitamin D supplementation, along with serial monitoring over more than two years, demonstrated persistently suppressed PTH secretion, supporting a diagnosis of permanent HypoPT. Thyroid imaging and antibody testing confirmed coexistent Hashimoto's thyroiditis, raising the possibility of an autoimmune contribution. To contextualize this case, we reviewed 14 previously published reports of COVID-19-associated HypoPT, among which no cases originating from China were identified. Based on available data, it cannot be ruled out that SARS-CoV-2 infection may contribute to the development of new-onset HypoPT in addition to worsening pre-existing conditions. Young-onset patients without a history of surgery-particularly those whose hypocalcemia severity does not clearly parallel the severity of infection-appear to have a higher likelihood of subsequent persistent dysfunction, though this observation remains preliminary. This case, together with the literature, underscores the need for extended follow-up in patients presenting with hypocalcemia and blunted PTH responses after COVID-19. Comprehensive autoimmune evaluation and, where appropriate, genetic testing should be considered to clarify etiology and guide long-term management.