What are the neurologic features of parathyroid dysfunction?
Up to 25% of patients with hyperparathyroidism have prominent psychiatric symptoms resembling mania, psychosis, or acute confusional state.
An additional 50% of hyperparathyroid patients may have symptoms suggesting depression. Interestingly, 80% of patients with hypoparathyroidism also exhibit psychological manifestations of their disease, including symptoms resembling depression, pseudodementia, mania, psychosis, and delirium.
In hyperparathyroidism, hypercalcemia-induced coma and spinal cord or root compression caused by collapse of decalcified vertebrae are the major nonpsychiatric symptoms.
Myopathy is also a common finding in hyperparathyroidism. In contrast, hypocalcemia resulting from hypoparathyroidism is more closely associated with seizures and tetany.
Seizures are often difficult to control and require correction of the electrolyte imbalance.
Latent tetany can present as laryngeal spasm and may also be evoked by mechanical stimulation of the facial nerve (Chvostek’s sign), by hyperventilation, or by occlusion of venous return from an arm resulting in carpopedal spasm (Trousseau’s sign).
