Neurologic and sensory complications associated with HSCT

Severe neurologic complications associated with hematopoietic stem cell transplantation (HSCT) have been reported in approximately 14-25% of all pediatric HSCT patients. The majority of severe neurologic events occur within the first 100 days after HSCT. Risk factors for developing severe neurologic events in the context of HSCT include the age of the HSCT recipient (children <3 years old), underlying disease, prior therapy, conditioning regimen, hematopoietic stem cell (HSC) source, unrelated donor, graft versus host disease (GvHD), immunosuppressive agents, metabolic disorders, and prior central nervous system (CNS) infections. The most common causes of developing a severe neurologic complication are medications (particularly calcineurin inhibitors), radiation-induced, hemorrhage-related, immune-mediated, and infection-induced. The most common severe neurologic events are seizures, cerebral vascular events as well as change in consciousness (mental status changes), and encephalopathy/leukoencephalopathy. Severe neurologic events account for 10-15% of all deaths in HSCT patients. Sensory complications such as radiation-induced cataracts, platinum-induced high-frequency hearing loss, and high-dose chemotherapy-induced taste dysfunction are seen quite often in pediatric HSCT recipients. Because pediatric HSCT recipients are still developing, effort needs to be made to minimize neurologic and sensory complications.