Internal Medicine Coding Alert

Solve the 337.1-versus-357.2 conundrum with this easy-to-reference guide

You're going to have to look at the patient's symptoms and history to assign polyneuropathy or autonomic neuropathy ICD-9 codes.

When coding for a diabetic patient with diabetic neuropathy, "What is the difference between 337.1 (Peripheral autonomic neuropathy in disorders classified elsewhere) and 357.2 (Polyneuropathy in diabetes)?" asks Robert Jackson, MD, an internist at Dickson Medical Associates with 28 physicians in Tennessee. "I've called insurers, and the representatives say there's no difference in coverage."

Impact: Using 337.1 or 357.2 comes down to meeting ICD-9 requirements to code to the highest specificity possible, Jackson says.

To code correctly, follow these guidelines.

You should report the primary or underlying disease causing the neuropathy or polyneuropathy first on the claim, says Susan West, RHIT, compliance auditor at Auditing for Compliance and Education (ACE) Inc. in Leawood, Kan. You should list the neurological manifestation (337.1 or 357.2) as a secondary diagnosis.

When coding for diabetic neuropathy, you will assign 250.6x (Diabetes with neurological manifestations ...) with the appropriate fifth digit, such as 0 (... type II or unspecified type, not stated as uncontrolled), as the primary diagnosis. Diabetes often causes neuropathy, which is a general term for damage or destruction of the peripheral nerves.

Rules: Adhere to these coding combinations:

1. Polyneuropathy (357.2) can only go with diabetes (250.6x).

2. But you can list neuropathy (337.1) with a primary diagnosis of diabetes (250.6x) or amyloidosis (277.30-277.39).

Before you nail down the neuropathy diagnosis, come to terms with the following vocabulary: Equate polyneuropathy with peripheral mononeuropathy. ICD-9 Coding Clinic lists 250.6x and 357.2 (Polyneuropathy in diabetes) as the codes for peripheral (or cranial) neuropathy (see "Fourth Digit 6: 250.6x" in 1991 third-quarter issue).

To identify peripheral neuropathy (polyneuropathy) versus autonomic neuropathy supporting chart notes, focus on the patient's symptoms and the E/M service's details. "The manifestations for peripheral and autonomic neuropathy are different," says Bruce Rappoport, MD, CPC, CHCC, a board-certified internist and medical director of Broward Health's Best Choice Plus and Total Claims Administration in Fort Lauderdale, Fla. Base the coding on the history and physical exam findings, he says.

Use this breakdown as a guide:

Symptoms: Think peripheral neuropathy when a patient has pain and numbness in her hands and feet. Patients typically describe the pain "as tingling or burning" and often compare the loss of sensation "to the feeling of wearing a thin stocking or glove," the Mayo Clinic says.

Causes: A patient may develop peripheral neuropathy due to traumatic injuries, infections, metabolic problems, and exposure to toxins.

"One of the most common causes of the disorder is diabetes," the Mayo Clinic says. "In many cases, peripheral neuropathy symptoms improve with time -- especially if it's caused by an underlying condition that can be resolved."

Action: "If the physician's notes indicate a peripheral polyneuropathy (with no additional specificity), the coder must look to the 357.x (Inflammatory and toxic neuropathy ...) code range depending on the underlying disease," says Marvel J. Hammer, RN, CPC, CCS-P, ACS-PM, CHCO, principal of MJH Consulting in Denver. You would use "2" as the fourth digit for diabetes.

What it is: A patient with autonomic neuropathy has damage to the nerves that regulate involuntary body functions, including heart rate, blood pressure, perspiration and digestion, the Mayo Clinic says. "Autonomic neuropathy results in faulty communication between your brain and the parts of your body that your autonomic nervous system serves."

Symptoms: Patients may experience dizziness, digestive and urination trouble, and sexual difficulties.

To treat autonomic neuropathy, the physician addresses the underlying cause, if possible, and manages the signs and symptoms.

Do this: "If the provider documents that the peripheral neuropathy involves the autonomic nervous system, the coder should look to 337.1," Hammer says.