Primary Care Coding Alert

Hint: Use fourth and fifth digit expansion to specify complications.

When your FP diagnoses diabetes mellitus or any manifestation of diabetes, you’ll have to scour through patient documentation to check diabetes type (type 1 or type 2) and look specifically for the type of complications and organ systems involved to arrive at the appropriate diagnosis code to report the condition using ICD-10 codes.

ICD-9: When a patient presents with diabetes, you must determine the fourth digit for 250.xx (Diabetes mellitus) according to the type of diabetic complication the patient has, if any. If the patient presents with diabetes without any complications, your first four digits will be 250.0 (Diabetes mellitus without mention of complication).

Regardless of whether the patient has Type 1 diabetes or Type 2 diabetes, you’ll report the diagnosis with the same parent code, 250 (Diabetes mellitus). Under ICD-9, the fifth digit provides the final two pieces of information on the patient’s diabetic condition: the diabetes type (I or II) and whether it is controlled. Under ICD-9, the fifth digit options are:

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

Caveat: Although you have different codes to report diabetes with complications, those codes are limited in their ability to specify the complications. For example, if a patient presents with Type 2 uncontrolled diabetes with the complication of proliferative diabetic retinopathy with macular edema, you’ll report the primary condition with 250.52 (Diabetes with ophthalmic manifestations, type II or unspecified type, uncontrolled). As you can see in this example, from that code you can only make out that there is an ophthalmic complication without actually knowing what the manifestation is. To identify the particular manifestation, you will need to use one or more additional codes. Thus, in this example, you would also report 362.02 (Proliferative diabetic retinopathy) and 362.07 (Diabetic macular edema).

Delve Deeper into Documentation to Check Complication Specifics

ICD-10 Change: When your diagnosis coding system changes, you’ll no longer flip to the same code section for both Type 1 and Type 2 diabetes. Although you are currently accustomed to starting off with “250” for all diabetes patients, your coding options will expand dramatically under ICD-10. Under ICD-10, you’ll have to report Type 1 diabetes with E10.xxx and Type 2 diabetes with E11.xxx. The fourth digit specifies the organ systems that show some manifestation, for example, ophthalmic/neurologic/renal, and the fifth (and, sometimes, sixth) digit elaborates the type of complication.

Type 1: You’ll code all Type 1 patients by starting out with the E10 series (Type 1 diabetes mellitus), and then you’ll move on from there after reviewing the patient’s chart to determine whether any further manifestations exist.

Example: Your FP sees a patient that presents with Type 1 diabetes with foot ulcer. In this case, you’ll look to E10 as your first three characters to reflect the Type 1 diagnosis, followed by the additional digits “621” to reflect that the patient has a foot ulcer complicating the diabetes condition that he is facing. Therefore, the full code will be E10.621 (Type 1 diabetes mellitus with foot ulcer).

Type 2: You’ll code all Type 2 patients by starting out with the E11 series (Type 2 diabetes mellitus), then moving on from there after reviewing the patient’s chart to determine whether any further manifestations exist.

Example: Your FP reviews a 55-year-old patient with Type 2 diabetes and kidney complications. Your FP arrives at a diagnosis of diabetic nephropathy due to diabetes mellitus.  In this instance, you’ll go straight to E11.x and scroll down to E11.21 (Type 2 diabetes mellitus with diabetic nephropathy).

Documentation: Just because Type I diabetes is often described as “juvenile type” or “juvenile onset,” don’t assume that all pediatric patients have Type I diabetes. It is becoming increasingly common for practitioners to diagnose and treat Type II diabetes developed in childhood or adolescence. Also, there are many instances wherein your FP might treat type 2 diabetes with insulin. So don’t automatically consider a patient who is being treated with insulin to be suffering from Type 1 diabetes.

Helpful in determining whether a patient has Type I or Type II diabetes is the results of a C-peptide assay, which measures insulin production and can indicate which type of diabetes is present. These test results may be important as you select your fifth digit under ICD-9, so check the documentation for those results.

Coder tips: When you prepare for ICD-10, adjust your superbills and electronic coding systems to offer the physicians the choice of Type 1 or Type 2 when they choose a diabetes diagnosis. Then leave a blank line marked “complication(s)” so that your FP can fill in any applicable complication, allowing you to select the most accurate code from among the many options available under ICD-10.