Laura Haugen
St. Louis Park, Minn.
Answer: A screening test is done for asymptomatic patients. A diagnostic test is for patients with symptoms. Because the medication is known to possibly be toxic, there is medical justification to run the liver function laboratory test. In this situation it would be considered a diagnostic test and not a screening test. It is considered medically necessary for the physician to obtain test results that play an integral part in the managing of the patients condition; therefore, the liver function lab test is not considered routine screening. The appropriate primary diagnosis code, indicating the reason for the test, is V58.69 (long term [current] use of high-risk medications). Code 710.0 (systemic lupus erythematosus) should also be reported as the underlying condition.