Hypoparathyroidism due to 22Q11 Deletion Syndrome Presenting as Acute Cardiomyopathy

Abstract

ABSTRACT: Objective: Discuss a unique presentation of hypoparathyroidism, an orphan disease with an estimated prevalence of 37 per 100,000 person-years in the United States.Methods: Describe the clinical presentation and pertinent laboratory data of a case of newly diagnosed hypoparathyroidism presenting as acute cardiomyopathy. A related literature review is also included.Results: A 34-year-old, previously healthy Caucasian female presented to the emergency room with progressive symptoms of heart failure and was found to have anemia, hypocalcemia, and hypoparathyroidism with an ejection fraction (EF) of 25 to 30% without structural cardiac abnormalities. Her labs revealed her hemoglobin was 6.4 g/dL, calcium was 4.9 mg/dL (reference range is 8.5 to 10.2 mg/dL), albumin was 3.4 g/dL (reference range is 3.5 to 5.5 g/dL), magnesium was 1.3 mg/dL (reference range is 1.7 to 2.2 mg/dL), phosphate was 4.9 mg/dL (reference range is 2.5 to 4.5 mg/dL), parathyroid hormone was 9 pg/mL (reference range is 14 to 64 pg/mL), and 25-hydroxyvitamin D was 31.9 ng/mL (reference range is 30 to 79 ng/mL). Pertinent history included normal early development, no previous neck surgery or radiation, and no family history of hypocalcemia, seizures, or intellectual disability. The patient did note recurrent ear infections. On physical exam, the patient had a nasal voice but no dysmorphic facies or visible palatal abnormalities and a normal cardiac exam. The patient's EF improved to 35% by hospital day 8 with stabilization of calcium levels. In follow-up, her EF was 50 to 55% at 1 month and then 60% at 5 months. Genetic testing revealed 22q11.2 deletion.Conclusion: This is the first reported adult case of 22q11 deletion syndrome presenting with reversible heart failure due to hypocalcemia secondary to hypoparathyroidism. Genetic testing is recommended for all cases of hypoparathyroidism without a clear known etiology even if they present in adulthood.Abbreviations: 22q11DS = 22q11 deletion syndrome; EF = ejection fraction