Snapshot An 8-month-old boy of central European descent is brought to the pediatrician due to progressive weakness, decreased visual attentiveness, and an exaggerated response when startled. He was born at 38 weeks gestation with no perinatal complications and an unremarkable prenatal history. At birth, he had no apparent deficits. On physical examination, there is no hepatosplenomegaly. On fundoscopy, there is a prominent fovea centralis, accompanied by pallor of the perifoveal macula. Laboratory testing is significant for 1% β-hexosaminidase A activity with normal β-hexosaminidase B isoenzyme activity in white blood cells. Introduction Clinical definition login to view 1 more bullet Epidemiology Incidence login to view 1 more bullet Location login to view 1 more bullet Risk factors login to view 2 more bullets ETIOLOGY Pathophysiology login to view 3 more bullets Genetics login to view 6 more bullets Presentation Symptoms login to view 7 more bullets Physical exam login to view 5 more bullets Studies Diagnostic criteria login to view 5 more bullets Differential Krabbe disease Gaucher disease Metachromatic leukodystrophy Treatment Conservative login to view 3 more bullets Complications Infection Poor weight gain Falls Prognosis In infantile-type of Tay-Sachs disease (TSD) leads to death before 5 years of age In juvenile-type TSD, death typically occurs in adolescence or late childhood In late-onset type of TSD, there is long-term survival