Part B Insider (Multispecialty) Coding Alert

Diagnosis Coding:

Select the Right Diabetes Code With 3 Quick Tips

Heed the etiology/manifestation sequencing guidelines.

Your patient’s diabetes impacts the care you provide and the reimbursement you receive. Make sure you know how to code for it correctly, or you could find yourself swimming in denials.

Before assigning a code for diabetes, you need to answer these three questions

1. What type of diabetes does your patient have?
2. Does the documentation indicate that the diabetes is uncontrolled?
3. Are there manifestations or complications of the diabetes?

Know the Types of Diabetes

In the average Part B practice, most often you’ll be coding for one of three types of diabetes:

Type I diabetes — Characterized by a lack of insulin production. Usually occurs during childhood or adolescence.

Type II diabetes — The most common form of diabetes. Results from the body’s ineffective use of insulin and usually occurs in people who are 45 years of age or older.

Secondary diabetes — Develops as a result of, or secondary to, another disease or condition.

Confusing: There are several diabetes-related terms that tend to cause confusion among coders. These include IDDM (insulin-dependent diabetes mellitus), NIDDM (non-insulin-dependent diabetes mellitus), adult-onset, and juvenile diabetes. Do not base your code selection on any of these descriptors.

If the medical record doesn’t clearly state the type of diabetes your patient has, ICD-9 coding guidelines direct you to default to Type II. But querying the physician for greater specificity will allow you to select a more precise code.

Mistake: Do not take into consideration the patient’s age when diabetes was diagnosed or the fact that the patient takes insulin when making your diabetes code selection. Taking insulin does not make a diabetic patient “insulin-dependent,” just as the patient’s age doesn’t concretely alert you to the type of diabetes.

Once you’ve determined which type of diabetes your patient has, you can begin to narrow down your diabetes code.

Look to category 250.xx (Diabetes mellitus) for Type I and Type II diabetes. These types of diabetes are caused by the inability of the body to produce or properly use insulin — not by another condition.

With category 250.xx codes, the fourth digit describes any diabetic manifestations and the fifth digit reports type and control.

Look to category 249.xx (Secondary diabetes mellitus) for patients with diabetes caused by another condition or event such as:

  • Cystic fibrosis
  • Malignant neoplasm of pancreas
  • Pancreatectomy
  • Adverse effect of a drug
  • Poisoning

With category 249.xx codes, the fourth digit describes any diabetic manifestations and the fifth digit reports control.

Know When to Report Uncontrolled

You should assign a fifth digit that indicates “uncontrolled” only when the physician documentation specifically indicates the diabetes is “uncontrolled” or “out of control.” Don’t get tripped up by adjectives like “poorly controlled,” “brittle,” or “resistant” or symptoms, such as hyperglycemia, glycosuria, or polyuria. These descriptors do not indicate the patient’s diabetes is “uncontrolled.”

You also cannot assume that diabetes is “uncontrolled” based on recent hospitalization, reported elevations in blood sugar readings, or the presence of manifestations. If you’re unsure of which fifth digit to select, consult the physician and document his response.

The default fifth digit for primary diabetes is “0” for type II or unspecified type, not stated as uncontrolled. This is because the majority of diabetics are Type II.

If your patient has Type II or unspecified diabetes, it’s only appropriate to report fifth digit “2” for type II or unspecified type, uncontrolled when the physician says the diabetes is uncontrolled.

Before you list fifth digit “1” for type I [juvenile type] not stated as uncontrolled or “3” for type I [juvenile type], uncontrolled make certain the physician documentation indicates that the patient has Type I diabetes.

Tip: Only report V58.67 (Long-term [current] use of insulin) for Type II diabetics who are on insulin. This code isn’t appropriate for Type I diabetics who require insulin.

Watch for Manifestations and Complications

The fourth digit of a diabetes code indicates whether the patient has any diabetic manifestations or complications. The diabetes codes make up the largest and most common group of etiology/manifestation combinations.

But you’ll need to be careful not to assume that a diabetic patient’s comorbidity is a manifestation. You must have physician documentation/confirmation indicating a cause-and-effect relationship before you can code a diabetic manifestation.

For example: Look for terms such as “in,” “due to,” “with,” “caused by,” “secondary to,” when trying to determine whether a co-morbidity is a diabetic manifestation.

Sequencing matters when coding for diabetic complications. Be careful to report the etiology (diabetes) and the manifestation together with diabetes listed first, followed by the manifestation when reporting primary diabetes.

With secondary diabetes, you’ll generally list diabetes code 249.xx first, followed by the manifestation(s), and the underlying cause for the diabetes. But if the underlying cause is the focus of care, you’ll list that code first and follow with the diabetes and manifestation codes.