Immune effector cell-associated neurotoxicity synd, grade 3

This code signifies a severe neurological toxicity, specifically grade 3, that arises as a complication of immune effector cell therapy, such as CAR T-cell therapy. It indicates significant neurocognitive dysfunction, motor weakness, seizures, or other severe neurological impairments directly attributable to the immune cell treatment.

Use this code when documentation clearly indicates a diagnosis of immune effector cell-associated neurotoxicity syndrome (ICANS) and specifies a grade of 3. This typically involves patients undergoing or recently having undergone cellular immunotherapy who present with acute, severe neurological symptoms requiring significant medical intervention. Supporting documentation would include physician notes detailing the neurological assessment, ICANS grading, and the causal link to immune effector cell therapy.

• Ensure the physician documentation explicitly states "grade 3" for ICANS; do not infer the grade.
• Always sequence this code after the underlying condition for which the immune effector cell therapy was administered, if applicable.
• Differentiate from other neurological complications not directly related to immune effector cell therapy or those with a lower grade.