P2.L229: Intracranial Calcifications in an Adolescent: A Case Report

Introduction: Fahr disease, also termed primary familial brain calcification, is a rare neurological disease involving abnormal intracranial calcium deposition, particularly in the basal ganglia. This genetic condition can result in progressive neurological dysfunction. We describe a patient found to have extensive intracranial calcifications, prompting evaluation for Fahr disease.

Case Description: A 14-year-old male with history of MEN2A, type 1 diabetes, and thyroidectomy with subsequent hypothyroidism and hypoparathyroidism was brought into the Emergency Department (ED) due to a seizure. He had no prior history of seizure activity. He was otherwise well until the morning of presentation when he awoke and noted that he was hyperglycemic (blood glucose in the 600s) and, shortly after, experienced 30 seconds of generalized tonic-clonic seizure activity. Upon presentation to the ED, he had returned to baseline with a normal neurologic exam. Laboratory work-up revealed persistent hyperglycemia and significant hypocalcemia with a corrected calcium of 6.9mg/dL. Electroencephalogram was normal. Initial head CT abnormalities led to an MRI which demonstrated extensive, symmetric, bilateral calcifications of the basal ganglia, thalami, and dentate nuclei. Parents later reported long-term nonadherence with his prescribed medication regimen of calcitriol and elemental calcium. He underwent calcium repletion and was restarted on his home medications. No further seizure activity occurred. Later genetic testing, to evaluate for Fahr Disease, was negative for the four most common mutations identified.

Discussion: The pattern and distribution of intracranial calcifications seen on the neuroimaging for this patient were consistent with what is classically seen in Fahr disease. Fahr disease (primary) is a rare, primarily autosomal dominant condition, due to numerous gene mutations. It typically presents in adult patients with abnormal intracranial calcium deposition, classically involving the basal ganglia, cerebellar dentate nuclei, and white matter. Over time, this can result in cerebral atrophy and progressive neurologic decline. Symptomatic patients commonly present with extrapyramidal and neuropsychiatric symptoms; seizures may occur but are less common. Further, patients with Fahr disease will have an otherwise benign workup; this distinguishes it from secondary intracranial calcifications (sometimes referred to as Fahr syndrome) in patients with underlying metabolic disorders/endocrinopathies, infections, or other degenerative processes. Given this patient’s history of medication non-adherence with notable hypocalcemia on presentation, his clinical picture is most consistent with that of secondary intracranial calcifications due to his undertreated hypoparathyroidism.

Conclusion: Fahr disease is a rare, inherited condition that typically presents in adult patients with progressive neurological dysfunction, though similar findings can be seen on neuroimaging in patients who develop intracranial calcifications secondary to underlying metabolic conditions such as hypoparathyroidism. In patients with symmetric, bilateral intracranial calcifications, particularly in the distribution described, further evaluation is warranted to evaluate for both primary and secondary causes.