Pathology/Lab Coding Alert

Question: When our lab performs repeat glucose testing for a patient with gestational diabetes that the physician treats with insulin, what should we use as the diagnosis code?
Iowa Subscriber Answer: You should report the diagnosis that the ordering physician provides as the reason for the test. The physician will probably report 648.8x (Abnormal glucose tolerance) with the fifth digit (0-4) indicating when during the pregnancy the condition or complication occurs. Because the insulin use is also pertinent to glucose testing frequency and medical necessity, you also should report V58.67 (Long-term [current] use of insulin). Caution: Do not assign a code from subcategory V58.6x for medication that a physician administers for a brief time to treat an acute illness or injury (such as a course of antibiotics to treat acute bronchitis). -- Reader Questions and You Be the Coder were prepared with the assistance of R.M. Stainton Jr., MD, president of Doctors- Anatomic Pathology Services in Jonesboro, Ark