Internal Medicine Coding Alert

Published on Fri Aug 08, 2008 PDF

Tip: What your physician documents is key

If you incorrectly dig into hypertension ICD-9 codes, you could set your claim up for limbo land. Take this true/false quiz to see if you're really going that necessary extra mile.

Question 1: Your internist's documentation specifies that the patient has hypertension. You have enough information to choose an accurate ICD-9 code.

True or false?

Question 2: If your internist doesn't specify the type of hypertension, you can assume that means benign because that's more common.

True or false?

Question 3: Malignant or benign hypertension is the highest degree of specificity you can get with one

To avoid taking up your internist's valuable time, you've got to be able to determine if documentation is sufficient to point you to a specific hypertension code.

See if you make the grade with these hypertension true/false answers.

If your internist is in the habit of merely writing "hypertension" on the patient's record, you should point this problem out to him.

Vital: The real key to correct coding for hypertension lies with physician documentation, and you must educate your internists to tell you explicitly what type of hypertension they're treating, according to Kristy F. Lane, CCP-P, coding specialist at a practice in Johnson City, Tenn. In other words, internists need to state the details of a patient's hypertension in the medical record.

Coding for hypertension really comes down to documentation. Often, internists will simply write "hypertension" in the diagnosis portion of their notes, which leads you to nothing but 401.9 (Essential hypertension; unspecified), says Phyllis Frazier, SCP-CA, a billing supervisor in Clarks Summit, Penn. "Many insurance carriers won't accept an unspecified code any longer," Lane says.

Action: Explain to your internists that adequate information for medical purposes isn't always adequate for coding purposes. They need to indicate whether a patient's hypertension is malignant or benign and also define how any other manifestations are related to the hypertension. "You've got a multitude of specific hypertension codes to choose from," Lane says.

When you don't know whether the hypertension is malignant or benign, you should never automatically assume your internist means benign.

Rule of thumb: "Never assume anything in coding," Lane says.

Heads up: The hypertension table in the ICD-9 manual's index lists three possible categories into which hypertension may fall: malignant, benign and unspecified. The fourth digit of the hypertension code you report will differ depending on which category you choose. For instance, you'll report 401.0 for malignant essential hypertension, 401.1 for benign essential hypertension, and 401.9 for unspecified.

"Do not use either .0 malignant or .1 benign unless medical record documentation supports such a designation," according to the 2007 ICD-9-CM Official Guidelines for Coding and Reporting.

Clues: "A patient has malignant hypertension when he has a recent significant increase over baseline blood pressure that is associated with target organ damage. There is usually vascular damage on funduscopic examination, such as flame-shaped hemorrhages or soft exudates," says Jerome Williams Jr., MD, FACC, a physician with Mid Carolina Cardiology in Charlotte, N.C. To diagnose malignant hypertension, papilledema must be present, Williams says.

Common assumption: Because benign hypertension is more common, physicians often assume they are indicating benign hypertension when they simply write "hypertension." But if the documentation doesn't specifically state "benign" or "malignant," the only accurate choice you have is to report an unspecified code, which insurance carriers may not accept.

Identifying whether the hypertension is benign or malignant won't tell your payers the whole story. You've also got to show whether the hypertension is primary or secondary to a patient's condition. When documenting, your internist must learn to link the patient's hypertension to any other manifestations. For instance, "you can code hypertension specifically as: with or without heart failure, hypertensive chronic kidney disease, a hypertensive heart and chronic kidney disease," Lane says.

Impact: You have to discern the manifestations properly to assign the correct code.

If the patient's hypertension is primary (also known as "essential hypertension," Williams says), meaning that another condition is not causing the hypertension, you need to list the hypertension code first. Then, go ahead and list any manifestations as secondary diagnoses.

Keep in mind: Patients sometimes have hypertension with another condition, such as renal disease or renal artery stenosis, and one code includes both conditions. For instance, 403.XX indicates hypertensive renal disease, and 404.XX indicates hypertensive heart and renal disease.

Red flag: If your internist documents that the patient has heart disease due to hypertension, he should also indicate whether the disease is with or without heart failure. "This distinction will help the coder select the best code in the 402 or 404 categories," Lane says. And if the patient has heart failure, remember to assign a separate code to indicate the type of heart failure.

A patient has secondary hypertension if the hypertension is "due to" or caused by another condition. ICD-9 defines secondary hypertension as "high arterial blood pressure due to or with a variety of primary diseases, such as renal disorders, CNS disorders, endocrine and vascular diseases."

For secondary hypertension, you should report the causal condition as the primary diagnosis and the hypertension as secondary. For example, if a patient has primary aldosteronism that is causing benign hypertension, you might report 255.10 (Primary aldosteronism) as the primary diagnosis and 405.19 (Secondary hypertension; benign; other) as the secondary.

-- Answers to You Be the Coder and Reader Questions were reviewed by 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.