Parkinsonism as an Atypical Manifestation of Primary Hyperparathyroidism

ABSTRACT Objective Primary hyperparathyroidism (PHPT) occurs as a result of hyperfunctional parathyroid glands resulting in an elevation of serum calcium levels. The association between hypoparathyroidism and parkinsonism have been frequently reported in the literature, while evidence of hyperparathyroidism associated with parkinsonism is rare. Methods The present study reports a case of a patient that had PHPT and developed symptoms of parkinsonism. Results A 75-year-old female patient with a history of diabetes mellitus, dyslipidemia, and systemic arterial hypertension presented to the emergency room due to unexplained drowsiness. Her serum calcium at the time was 14.2 mg/dL. A cervical ultrasound was performed, and the presence of a 2.5 × 1.9-cm nodule in the left lower parathyroid region was identified. Three days later, scintigraphy with the use of sestamibi showed an increased capture of the marker in the same region, suggesting parathyroid hyperfunction. During hospitalization, the patient developed symptoms of parkinsonism. A left inferior parathyroidectomy was performed, with normalization of serum calcium levels and a remission of drowsiness, in addition to a significant improvement in parkinsonian symptoms. The patient remained free of parkinsonism over 3 years of follow up. Conclusion Parathyroidectomy can provide a significant remission of parkinsonism in a patient with PHPT. Even though it is rare, the relation between parkinsonism and PHPT exists.