Neurology & Pain Management Coding Alert

Watch these terms to avoid confusion over dementia diagnoses.

When your neurologist assigns a diagnosis of Alzheimer's disease, you'll report ICD-9 code 331.0. But what if you're coding for a different diagnosis? Read on for the rundown on similar conditions and documentation clues to help you code correctly.

Match Your Codes to These Terms

"Physicians should document symptoms of additional severity if they exist," says Marianne Wink, RHIT, CPC, ACS-EM, a coder in Ontario, N.Y. "This might not add anything to reimbursement for E/M at the moment, but just documenting and coding 'dementia' or 'Alzheimer's' doesn't always report the severity of the disease."

Lewy bodies: Dementia with Lewy bodies is characterized by abnormal deposits of a certain protein that form inside the brain's nerve cell. Researchers have found Lewy bodies (named after the scientist who first discovered them) in several brain disorders. Patients can experience symptoms similar to Alzheimer's, such as acute confusion, fluctuating cognition, delusions, and more. Your neurologist might document dementia with Lewy bodies, Lewy body disease, LBD, or dementia with Parkinsonism.

Each of these terms leads to 331.82 (Dementia with Lewy bodies).

Hippocampal sclerosis: Approximately 65 percent of patients with temporal lobe epilepsy have neuron cell loss, primarily in the hippocampus. The hippocampus is located in the medial temporal lobe of the brain and helps regulate emotions and convert short term memory to more permanent memory. Scientists still debate whether hippocampal sclerosis helps cause or is a consequence of chronic, medication-resistant seizures. The physician might diagnose hippocampal sclerosis, Ammon's horn sclerosis (AHS), or temporal lobe epilepsy (TLE) in patients. You'll submit 348.81 (Temporal sclerosis).

Vascular dementia: As the second most common form of dementia after Alzheimer's, you might see "vascular dementia" on charts fairly often. Problems in the blood supply to the brain cause vascular dementia. ICD-9 contains several coding options, based on the patient's associated symptoms. Most fall under the category 290.4x (Arteriosclerotic dementia):

• 290.40 -- Vascular dementia, uncomplicated
• 290.41 -- Vascular dementia, with delirium
• 290.42 -- Vascular dementia, with delusions
• 290.43 -- Vascular dementia, with depressed mood
• 294.8 -- Other persistent mental disorders due to conditions classified elsewhere.

Watch your physician's documentation for clues to help you choose the most accurate diagnosis. Updated ICD-9 guidelines in 2010 included new clarification that "the word 'with' should be interpreted to mean 'associated with' or 'due to' when it appears in a code title, the Alphabetic Index, or an instructional note in the Tabular List.'" Some patients with vascular dementia also have epilepsy, in which case you would report an additional ICD-9 code for associated epilepsy (345.0-345.9).

Generalized brain atrophy: A number of conditions affecting the brain can lead to brain atrophy, or cerebral atrophy. The patient loses brain cells or the connections between brain cells become damaged. Primary causes can include epilepsy, traumatic brain injury, stroke, Alzheimer's, multiple sclerosis, or cerebral palsy. When the neurologist documents generalized brain atrophy, you'll report either 331.2 (Senile degeneration of brain) or 331.9 (Cerebral degeneration unspecified), depending on the situation.

Research Highlights Potential Confusion

You'll always code based on your physician's documentation, but providers might need to pay closer attention to Alzheimer's diagnoses in the future.

Why: New research shows that physicians might easily misdiagnose Alzheimer's disease and similar illnesses in the elderly, according to a February 23 press release from the American Academy of Neurology.

The study found that about half of the patients diagnosed with Alzheimer's disease did not have sufficient numbers of brain lesions to support the diagnosis. Patients who hadn't been diagnosed with Alzheimer's often had enough lesions to support a diagnosis associated with another type of dementia, such as those listed above.

"Diagnosing specific dementias in people who are very old is complex, but with the large increase in dementia cases expected within the next ten years in the United States, it will be increasingly important to correctly recognize, diagnose, prevent, and treat age-related cognitive decline," said study author Lon White, M.D., M.P.H., with the Kaukini Medical System in Honolulu.

The study, supported by the National Institute on Aging and the Department of Veteran Affairs, will be presented during the ANA's annual meeting in April.