Internal Medicine Coding Alert

Question: An established patient with uncontrolled type II diabetes who is on insulin and has dizziness and a headache reports to the internist. The patient reports that she forgot to take her insulin for a few days and attempted to "make up" the lost doses with extra injections. During a level-three E/M, the physician determines the patient had an accidental overdose. How many diagnosis codes should I report?

Missouri Subscriber

Answer: You'll need five ICD-9 codes in order to capture all of the patient's ailments for this encounter.

Code order: When reporting all of these codes, be sure to place them in the proper order on the claim. If a patient has taken the wrong drug or takes the correct drug in the incorrect dosage, you should first report the poisoning code for the drug taken. Then report codes for signs and symptoms that indicate the manifestation of the poisoning. Third, you should choose the appropriate E code to indicate the external cause of the poisoning. Finally, include an ICD-9 code to represent the patient's underlying condition.

On the claim, report 99213 (Office or other outpatient visit for the evaluation and management of an established patient, which requires at least two of these three key components: an expanded problem-focused history; an expanded problem-focused examination; medical decision-making of low complexity) for the E/M.

And be sure to append the following diagnosis codes, in this order, to 99213 to explain the specifics of the encounter:

• 962.3 (Poisoning by hormones and synthetic substitutes; insulins and antidiabetic agents) for the overdose

• 780.4 (Dizziness and giddiness) for the dizziness

• 784.0 (Headache) for the headache

• E858.0 (Accidental poisoning by other drugs; hormones and synthetic substitutes) to represent the cause of the overdose

• 250.02 (Diabetes mellitus without mention of complication; type II or unspecified type, uncontrolled) to represent the patient's diabetes.