Pathology/Lab Coding Alert

Question: The ordering physician requested a stool culture for a patient with severe stomach cramps and diarrhea who had been exposed to a family member with shigellosis. The lab performed an immunoassay for antigen detection. The culture was positive for Shigella species, the physician diagnosed shigellosis. What are the procedure and diagnosis codes?

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Answer: The correct procedure code for the stool culture is 87405 (Culture, bacterial; stool, aerobic, with isolation and preliminary examination (eg, KIA, LIA), Salmonella and Shigella species). The test provides a presumptive identification to the genus level.

Dx: Shigellosis is caused by a group of bacteria called Shigella, leading to diarrhea, fever, and stomach cramps. Without more specific information, the correct diagnosis code in this case is A03.9 (Shigellosis, unspecified).

However, ICD-10-CM provides a series of specific codes that you could use if the lab performed additional tests to identify the Shigella species or type, including the following:

• A03.0 (Shigellosis due to Shigella dysenteriae)
• A03.1 (Shigellosis due to Shigella flexneri)
• A03.2 (Shigellosis due to Shigella boydii)
• A03.3 (Shigellosis due to Shigella sonnei)
• A03.8 (Other shigellosis)