2025 ICD-10-CM code G93.40
(Active) Effective Date: N/A Revision Date: N/A Neurological Disorders - Other disorders of the nervous system Chapter 6: Diseases of the nervous system Feed
Unspecified encephalopathy is a brain disorder of unknown or undocumented cause.
Modifiers may be applicable depending on the circumstances of the service.Always consult your payer's guidelines for specific modifier requirements.
Medical necessity is established by the presence of symptoms and signs consistent with encephalopathy and the physician's determination that further investigation is required to establish a definitive diagnosis.The need for diagnostic testing and potential treatment of symptoms supports the medical necessity for this code.
The clinical responsibility involves a thorough history and physical exam, ordering and interpreting various laboratory and imaging studies (CBC, CMP, electrolytes, autoantibodies, toxicology, CT, MRI, EEG, Doppler ultrasound), forming a differential diagnosis, and managing the patient based on the suspected etiology, as well as managing any emergent symptoms.
- Chapter 6: Diseases of the nervous system
- G93.40 falls under the broader category of "Other disorders of the nervous system" (G89-G99) within Chapter VI of the ICD-10-CM.
In simple words: Unspecified encephalopathy means there's brain damage, disease, or dysfunction, but doctors haven't figured out the exact cause.Symptoms vary widely but could include confusion, tiredness, memory problems, seizures, shaking, or muscle pain. Doctors use tests like blood work, brain scans, and an EEG to try and find out what's wrong, and treatment depends on the underlying cause.
Unspecified encephalopathy (G93.40) in ICD-10-CM represents a broad category encompassing various forms of brain damage, disease, or dysfunction where the specific etiology remains unspecified or un documented in the medical record.Symptoms can manifest diversely, potentially including altered mental state, lethargy, cognitive impairment (dementia), seizures, tremors, muscle twitching (myoclonus), and myalgias.Diagnosis relies on a comprehensive clinical evaluation encompassing medical history, physical examination, and various diagnostic tests such as complete blood count (CBC), comprehensive metabolic panel (CMP), electrolyte levels, autoantibody analysis, toxicology screenings, neuroimaging (CT, MRI, Doppler ultrasound), and electroencephalography (EEG). Treatment strategies are highly individualized and dictated by the underlying, unidentified cause.Possible therapeutic interventions might include supportive measures like oxygen therapy for hypoxic episodes, dialysis or kidney transplantation in cases of uremic encephalopathy, glucose administration for hypoglycemia, or insulin for hyperglycemia.
Example 1: A patient presents with altered mental status, confusion, and lethargy following a motor vehicle accident.Initial investigations are unrevealing, and the physician documents "acute encephalopathy, unspecified," pending further evaluation., A patient with a history of poorly controlled hypertension experiences sudden onset of headache, altered consciousness, and seizures.Brain imaging shows cerebral edema.The attending physician documents "hypertensive encephalopathy" but does not assign the more specific code, only selecting G93.40., A previously healthy individual develops progressive cognitive decline, unsteady gait, and tremor.Despite extensive workup, including neuroimaging and laboratory testing, no specific cause is identified.The physician documents "encephalopathy, unspecified" as the most appropriate diagnosis.
Detailed clinical history, physical examination findings, results of relevant laboratory tests (CBC, CMP, electrolytes, autoantibodies, toxicology screen), neuroimaging reports (CT, MRI, Doppler ultrasound), electroencephalography (EEG) results, and a clear statement from the physician regarding the inability to specify the cause of the encephalopathy.
** This code is broad and should be used cautiously.Always document the clinical findings justifying the use of this code, and keep in mind that this code's application may depend on the specific clinical circumstances and payer guidelines.
- Payment Status: Active
- Modifier TC rule: Not applicable; this is a diagnosis code, not a procedure code.
- Specialties:Neurology, Internal Medicine, Critical Care Medicine
- Place of Service:Inpatient Hospital, Outpatient Hospital, Office, Emergency Room - Hospital, Skilled Nursing Facility, Other Place of Service