Adult‐onset Krabbe disease presenting as isolated sensorimotor demyelinating polyneuropathy: A case report

Abstract Krabbe disease is a rare autosomal recessive neurodegenerative disease, caused by mutations in the GALC gene, which encodes for the lysosomal enzyme galactocerebrosidase. Typical clinical manifestations of Krabbe include psychomotor deterioration, visual loss, seizures, and spasticity, that result from central nervous system demyelination. We report a case of a 35‐year‐old male with Krabbe who presented in adulthood with isolated severe, upper extremity predominant demyelinating sensorimotor polyneuropathy and did not develop other distinguishing clinical or radiological features of Krabbe until the later stages of the disease. The patient's diagnostic odyssey lasted 13 years from presentation to diagnosis, which was ultimately determined with the use of whole exome sequencing (WES) at the age of 48 years. The expanding phenotypic spectrum of adult‐onset Krabbe Disease (AOKD) presents a diagnostic challenge that can lead to diagnostic delays and potentially affect treatment options. Our patient's case underscores the importance of pursuing WES in those with undiagnosed progressive neuromuscular disorders.