Coding Diabetes With Diabetic Retinopathy

Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness in American adults. Diabetic retinopathy is present in a significant number of patients and consumes significant health care resources. According to the National Eye Institute up to 45 percent of adults diagnosed with diabetes have some stage of diabetic retinopathy. Therefore it is important that the condition itself and the guidelines for coding diabetic retinopathy are understood.

Diabetic retinopathy is a progressive disease caused by microvascular changes in the retina. Patients who have been diabetic for a number of years and/or those who have poor control of blood sugar levels are more likely to develop diabetic retinopathy. Common symptoms include blurred vision, decreased vision, flashes and floaters, and vision loss. However, patients with early retinopathy may not experience any symptoms.

Coding Diabetic Retinopathy
Codes for diabetes are assigned using codes from categories 250, Diabetes Mellitus, and 249, Secondary diabetes.

The fourth digit of 5 is used with codes from categories 249 and 250 to indicate diabetes with ophthalmic manifestations, in this case diabetic retinopathy. The type of diabetes and whether it is controlled or not controlled determines the fifth digit assignment. Refer to the ICD-9-CM code book for the listing of the appropriate 5th digits for categories 249 and 250.

Once the diabetes with ophthalmic manifestation code has been assigned (250.5X), codes that identify the specific diabetic retinopathy from subcategory 362.0, Diabetic retinopathy, must then be assigned. The codes for diabetic retinopathy, 362.01 through 362.06, are manifestation codes. Therefore they cannot be listed as the principal diagnoses or sequenced first. The appropriate diabetes code 249.5X or 250.5X must be sequenced first followed by a code from subcategory 362.0.

The following codes are used to report the manifestation of diabetic retinopathy:

362.01, Background diabetic retinopathy

Background diabetic retinopathy occurs when the diabetes causes dilation and leaking in the retinal arteries, forming small hemorrhages and fluid accumulation. This leads to retinal edema and swelling that distorts and decreases the patient’s vision. Code 362.01 is assigned when the documentation in the medical record does not indicate the specific type of diabetic retinopathy.

362.03 Nonproliferative diabetic retinopathy NOS

362.04 Mild nonproliferative diabetic retinopathy

362.05 Moderate nonproliferative diabetic retinopathy

362.06 Severe nonproliferative diabetic retinopathy

Nonproliferative diabetic retinopathy is the earliest phase of the disease and is characterized by retinal vascular abnormalities including microaneurysms, intraretinal hemorrhages and cotton-wool spots or small areas of yellowish-white coloration in the retina. Nonproliferative diabetic retinopathy can progress from mild to moderate to severe and there are specific codes for each stage.

Mild: At this earliest stage, microaneurysms occur. They are small areas of balloon-like swelling in the retina’s tiny blood vessels.

Moderate: As the disease progresses, some blood vessels that nourish the retina are blocked.

Severe: Many more blood vessels are blocked, depriving several areas of the retina with their blood supply. These areas of the retina send signals to the body to grow new blood vessels for nourishment.

If the specific stage of nonproliferative diabetic retinopathy is not documented then code 362.03, Nonproliferative diabetic retinopathy NOS, is assigned.

362.02, Proliferative diabetic retinopathy

Proliferative diabetic retinopathy is the later and more serious phase of the disease. Diabetes causes the retinal vessels to become ischemic, depriving the retina of oxygen and encouraging tiny new vessels to form to increase oxygenization, also called neovascularization. The new vessels are fragile and often rupture, causing retinal and vitreous hemorrhages that distort and decrease vision and create floaters.

362.07, Diabetic macular edema

Diabetic macular edema is swelling of the retina in diabetes mellitus due to leaking of fluid from blood vessels within the macula that only occurs with diabetic retinopathy. As macular edema develops, blurring occurs in the middle or just to the side of the central visual field. Visual loss from diabetic macular edema can progress over a period of months and make it impossible to focus clearly.

Diabetic macular edema is only present with diabetic retinopathy; therefore code 362.07 can only be used when a code for diabetic retinopathy, 362.01-362.06, is also assigned.

Documentation in the medical record should be reviewed to assign the correct diabetic retinopathy code. Query the physician if there is missing or conflicting documentation.

Review the previous CCS Prep column titled “Test Preparation Must Included Brushing Up on Guidelines for Coding Diabetes Mellitus,” for further information on assigning diabetes codes, specifically 5th digit reporting. Also review the following Coding Clinics:

4th Quarter 2005, pp. 64-67
2nd Quarter 2001, p. 16
3rd Quarter 1996, p. 4
Number 5 1993, p. 3
3rd Quarter 1991, pp. 8-9

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After review, test your knowledge with the quiz below:

1. A male patient presents to the clinic for a retinal evaluation of diabetic retinopathy. He was diagnosed with type II diabetes mellitus 15 years ago and is currently taking Glucophage. The patient was diagnosed with severe nonproliferative diabetic retinopathy. How should the diagnoses for this case be coded?

a. 362.06, 250.50

b. 250.50, 362.06

c. 250.52, 362.06

d. 250.50, 362.03

2. A patient with diabetic retinopathy is admitted to the hospital because of uncontrolled diabetes. Which of the following is the correct diagnosis code assignment?

a. 250.92, 250.52, 362.01

b. 250.52, 250.92, 362.03

c. 250.93, 250.53, 362.01

d. 250.52, 362.01

e. 250.53, 362.03

This month’s column has been prepared by Cheryl D’Amato, RHIT, CCS, director of HIM, facility solutions, Ingenix, and Melinda Stegman, MBA, CCS, clinical technical editor, Ingenix (www.ingenix.com).

CPT is a registered trademark of the American Medical Association.

Answers:
1) b. Assign code 250.50, Diabetes with ophthalmic manifestations, type II or unspecified type, not stated as uncontrolled, as the first listed code for this encounter. Code 362.06, Severe nonproliferative diabetic retinopathy, should be assigned as an additional diagnosis. 2) d. Code 250.52, Diabetes with ophthalmic manifestations, Type II or unspecified, uncontrolled, is assigned as the principal diagnosis. Code 362.01, Background diabetic retinopathy, is assigned as an additional diagnosis to identify retinopathy. This code is assigned when the specific type of diabetic retinopathy is not identified. Code 250.9x, Diabetes with unspecified complication, would not be assigned as an additional diagnosis and is never assigned with any other code from the 250.0x-250.8x series. Code 250.92 would have been appropriate if “uncontrolled diabetes” was documented without mention of any further manifestations.