Pearls & Oy-sters: Spinal Cord Candidiasis Linked to CARD9 Deficiency Masquerading as a Longitudinally Extensive Transverse Myelitis.

<i>Candida</i> spp. myelopathies are very rare. We report a case of subacute longitudinally extensive transverse myelitis in an apparently immunocompetent 55-year-old man. After a negative infectious workup, corticosteroids and plasma exchange were initiated. Although there was a transient initial improvement, symptoms then worsened, and the lumbar puncture was repeated. <i>Candida albicans</i> was isolated in the CSF, and a diagnosis of spinal cord candidiasis was made. Gene panel sequencing for inborn immune deficiencies identified a homozygous disease-causing <i>CARD9</i> variant. Despite antifungal treatment, necrotic myelitis, meningoencephalitis, and cerebral vasculitis developed. Fungal spinal cord infections can mimic inflammatory myelitis, and beta-D-glucan testing of both serum and CSF may help narrow down the diagnosis. In cases of severe or unexpected invasive <i>Candida spp.</i> infection, even adults and apparently immunocompetent patients should be screened for inborn immune deficiencies and CARD9 deficiency in particular.