Internal Medicine Coding Alert

Eye on diabetic complications related to current episode of care.

Long-gone are the days of reporting the same diagnosis code for all your diabetes patients. Add in factors such as your internal medicine physician seeing patients with more complex cases and their stepping in to treat diabetic manifestations, and choosing the correct diabetes diagnosis can seem quite complicated. Use these three steps for definitive diabetes diagnosis coding to ensure that your ICD-9 codes justify the services you bill.

1. Select the Fourth Digit First

You'll begin code selection with diagnosis family 250.xx (Diabetes mellitus). Determine the fourth digit according to the type of diabetic complication the patient has, if any.

Example: A patient presents with diabetic hypoglycemia. You should report 250.8 (Diabetes with other specified manifestations) as your first four digits. If, however, the patient presents with diabetes without any complications, your first four digits will be 250.0 (Diabetes mellitus without mention of complication).

Take note: Diabetes patients might have more than one complication. If so, you should code only the complication most relevant to services the physician renders that day.

2. Identify the Type for Fifth Digit

The fifth digit of the diagnosis code provides the final two pieces of information on the patient's diabetic condition: the diabetes type (I or II) and whether or not it is controlled.

To select the proper fifth digit, you must first know what the following ICD-9 descriptor terms mean:

• Type I -- The patient's pancreatic beta cells no longer produce insulin. People with type I diabetes must take insulin. ICD-9 descriptors also refer to type I as "juvenile type" diabetes.
• Type II -- The patient's beta cells do not produce sufficient insulin, or the beta cells have developed insulin resistance. People with type II may not have to take insulin.

Not stated as uncontrolled " The patient's diabetes is managed sufficiently by diet and/or insulin.

Uncontrolled " A patient can have uncontrolled diabetes when the physician documents that blood sugar levels are not acceptably stable under the current treatment regimen, when the patient is not in compliance with his diabetes management plan, or if the patient is taking medications for another illness that interfere with diabetes management.

First, check the physician's documentation to see what type of diabetes the patient has and whether the condition is controlled. Then choose one of the following fifth digits:

• 0 -- Type II or unspecified type, not stated as uncontrolled
• 1 -- Type I (juvenile type), not stated as uncontrolled
• 2 -- Type II or unspecified type, uncontrolled
• 3 -- Type I (juvenile type), uncontrolled.

"The one problem I have is that the doctors don't specify in the medical record the type of diabetes the patient has and if it is controlled or uncontrolled," says Vonda Pickelsimer, a physician coder in Greenville, S.C. Work with your physicians to include those details in documentation, so you can choose the best code.

Juvenile caution: Just because Type I diabetes has the phrase "juvenile type" in parentheses following the descriptor, don't assume that all young patients your internist treats have Type I diabetes. Children or adolescents can also develop Type II diabetes.

Insulin caution: Just because the patient is taking insulin does not mean that he or she is Type I, it is often referred to as "insulin-dependent," and Type II may be referred to as "non-insulin dependent." However, it is possible that a Type II diabetic may be taking insulin as part of his or her treatment regimen, so if you see that the physician has prescribed insulin for the patient, don't assume the patient is Type I.

Results of a C-peptide assay can be helpful in determining whether a patient has Type I or Type II diabetes, and what you select as your fifth digit. This test measures insulin production and can indicate which type of diabetes is present.

3. Determine if Diabetes Is Primary

After you've chosen the patient's correct 250.xx code, a new question can arise: Is diabetes the primary or secondary diagnosis?

In most cases, the physician will treat a problem not directly related to the diabetes, but you may still need to indicate the patient's complete medical condition with a 250.xx code.

Example: A diabetic patient presents with a urinary tract infection (599.0). Code the infection as the primary diagnosis, and list the diabetes mellitus as the secondary diagnosis (such as 250.00). Diabetes is secondary, because it is a relevant condition that influences the patient's treatment and care but did not lead to the infection and is not the primary reason for the encounter or the focus of the visit.

If, however, the patient presents with a diabetic condition or with a condition due to diabetes (such as diabetic ketoacidosis), the diabetes diagnosis code must be sequenced as the principal diagnosis (such as 250.13, Diabetes with ketoacidosis; type I (juvenile type), uncontrolled), followed by the code for the specific condition (such as infectious gastroenteritis, 009.1).