A SLC1A3 variant associated with hemiplegic migraine and acetazolamide-responsive MRS changes

<p>Familial hemiplegic migraine (FHM) is a group of rare familial disorders caused, in most cases, by mutations in <em>CACNA1A</em> and <em>ATP1A2</em>.^{<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R1">1</a>} Heterozygous mutations in solute carrier family 1 member 3 (<em>SLC1A3</em>), encoding glial glutamate transporter, are associated with episodic ataxia type 6 (EA6).^{<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R2">2</a>,<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R3">–</a><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R5">5</a>} In addition to episodic ataxia (EA), alternating hemiplegia and hemiplegic migraine have been reported twice in patients with EA6.^{<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R2">2</a>,<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R4">4</a>} Mutations in <em>SLC1A3</em> are very rare; screenings in cohorts of EA and alternating hemiplegia have yielded either negative results^{<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R3">3</a>,<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R6">6</a>,<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R7">–</a><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357413/#R8">8</a>} or variants of unclear significance.^e-1--e-3 Herein, we characterize a patient featuring sporadic hemiplegic migraine (SHM) responsive to acetazolamide (ACZ) and mild cerebellar atrophy associated with a new variant in <em>SLC1A3.</em> We also report the utility of proton magnetic resonance spectroscopy (MRS) for this condition.</p>