Cauda Equina Syndrome Following CAR-T & the Role of Physiatrists in the Interdisciplinary Care Team: A Case Report

Case Diagnosis: 45-year-old Male with Cauda Equina Syndrome following Chimeric Antigen Receptor T-Cell therapy (CAR-T)

Case Description or Program Description: The patient received CAR-T for B-Cell Acute Lymphoblastic Lymphoma and developed acute onset right greater than left lower extremity weakness with hypoesthesias and paresthesias, neurogenic bowel with incontinence, and neurogenic bladder with urinary retention. Magnetic resonance imaging of the lumbar spine revealed cauda equina nerve root enhancement. EMG was suggestive of bilateral polyradiculoneuropathies. The patient received physical and occupational therapies during their 14-day acute inpatient stay and was then transferred to inpatient rehabilitation. The prior level of function was modified independent. The level of function at the time of admission to inpatient rehabilitation was moderate assist for mobility and maximum assist for lower body dressing and toileting. Their activity duration was limited by episodes of bladder incontinence. Patient participated in an 11-day interdisciplinary medical rehabilitation program and was discharged at the overall functional goal level of modified independent at the wheelchair level.

Setting: Tertiary Medical Center, Inpatient Rehabilitaiton Unit

Assessment/Results: On discharge, the patient improved to touch assist for lower body dressing and performing wheelchair mobility at the supervision level. He was started on terazosin for neurogenic bladder with urinary retention that eventually transitioned to urinary incontinence, however this resolved after discontinuation of terazosin.

Discussion (relevance): CAR-T therapy is a relatively new FDA-approved (August 2017) oncology treatment that is gaining widespread adoption. However, it is associated with known side effects, including immune effector cell-associated neurotoxicity syndrome (ICANS), which can manifest as various neurological dysfunctions. This increase in neurotoxic effects highlights the growing need for physiatric care within this patient population.

Conclusions: Physiatrists play a crucial role for patients who develop neurotoxicity following CAR-T therapy by optimizing functional recovery through comprehensive rehabilitation strategies, neuromuscular re-education, mobility training, pain management, and bladder dysfunction interventions to enhance quality of life and independence.