Delirium due to conditions classified elsewhere

This code signifies an acute confusional state characterized by fluctuating consciousness, disorientation, and cognitive impairment, directly resulting from an underlying medical condition or substance. It represents a secondary mental disorder where the delirium is a symptom of another primary physical illness.

Use this code when documentation clearly links the patient's delirium to an identifiable medical condition (e.g., infection, metabolic disturbance, organ failure, drug toxicity/withdrawal) that is classified elsewhere. The medical record should explicitly state "delirium due to [underlying condition]" or similar phrasing indicating a causal relationship.

• Always code the underlying medical condition first, as the delirium is a manifestation of that primary illness.
• Distinguish from dementia (290.xx) which is a chronic, progressive decline, and not typically acute or fluctuating.
• Ensure the documentation specifies the etiology; "delirium NOS" would be coded differently.