Question: The lab received corneal scrapping specimen from a patient with infected keratitis, and performed a gram stain plus aerobic and anaerobic culture. We isolated and identified Pseudomonas aeruginosa from the aerobic culture, and performed antibiotic susceptibility testing using the disk method. What are the correct codes for this scenario? Washington subscriber Answer: Report the Gram stain on the scraping or swab as 87205 (Smear, primary source with interpretation; Gram or Giemsa stain for bacteria, fungi, or cell types). You should also report the procedure code for each culture, even though the lab identifies an isolate from only the aerobic culture. The correct codes are as follows: List the antibiotic susceptibility testing as 87184 (Susceptibility studies, antimicrobial agent; disk method, per plate (12 or fewer agents)).