A case report of a person diagnosed with Fahr’s disease related to post-thyroidectomy hypoparathyroidism highlights the importance of doing regular screening, including brain scans and blood tests, after this surgery.
Fahr’s disease is a rare and under-reported disorder in which calcium deposits form in the areas of the brain that are responsible for controlling movement. The cause of Fahr’s disease is largely unknown, with treatment mostly aimed at managing symptoms, but it has been linked to some metabolic disorders.
The report details a 56-year-old woman admitted to a hospital after a one-year history of seizures, uncontrolled limb movements, difficulty swallowing, and insomnia. These symptoms had come on gradually, and her family also reported changes in behavior like abnormal forgetfulness and irritability.
The patient’s medical history was largely unremarkable, but she had undergone a subtotal thyroidectomy — partial removal of the thyroid gland — 25 years before her hospitalization. She had previously been treated with anti-epileptics and anti-psychotics, and there was some improvement. But in the months before coming to the hospital, her symptoms had gotten worse, so medications were stopped.
Blood work identified irregular calcium and phosphate levels, as well as low levels of parathyroid hormone, all of which can be indicative of Fahr’s disease. But the only way to get a definitive diagnosis is to look for calcification in the brain.
A CT scan revealed large calcium deposits in the brain, confirming a Fahr’s diagnosis. The disease was considered to have occurred as a consequence of post-thyroidectomy hypoparathyroidism.
The patient was started on calcium and vitamin D supplements to help get their levels back to more regular values. This, according to the researchers who wrote the case report, “resulted in some improvement.”
This report highlights Fahr’s syndrome as a slow-developing, under-reported condition that can develop after thyroidectomy. The researchers “recommend CT imaging and measurement of serum calcium levels as part of long-term follow-up of patients after thyroidectomy.” They noted that CT imaging is preferred because calcium deposits do not show up as well on MRI scans.