Gastroenterology Coding Alert

Can You Code This Gastroenteritis Case?

Question: Recently a mother came in with her 4-year-old who had been experiencing diarrhea, vomiting, and abdominal pain for two days, accompanied by a low-grade fever. Our gastroenterologist noticed the child was lethargic and appeared dehydrated. The provider diagnosed gastroenteritis and ordered a stool test to determine the origin. The patient and mother came in for a follow-up two days later. The fever and stomach pain were the only symptoms reported, and the test results said norovirus was the origin. Which ICD-10 codes do I report for these encounters?

Michigan Subscriber

Answer: For the first visit, you’ll report K52.9 (Noninfective gastroenteritis and colitis, unspecified) because the origin was not known.

Based on what’s written in this case, you will also report the following symptoms codes:

• R11.2 (Nausea with vomiting, unspecified)
• R19.7 (Diarrhea, unspecified)
• R50.9 (Fever, unspecified)
• E86.0 (Dehydration)

Remember: You likely know from memory that R10.- codes describe abdominal pain, but you won’t report abdominal pain for this case. You’ll only select a code from R10.- if “a related definitive diagnosis has not been established (confirmed) by the provider,” per ICD-10 coding guideline I.C.18.a. Because the pediatrician made a diagnosis that implies stomach pain, you’ll only use an R10 code if the stomach pain is not “associated routinely with a disease process,” as guideline I.C.18.b goes on to tell you.

Medical necessity: The pediatrician ordered a stool test to further assess the origin of the gastroenteritis. Reporting the abovementioned symptoms will help support the medical need for this test.

For the second encounter, the pediatrician determined that Norovirus virus is the cause of the stomach condition, which codes to A08.11 (Acute gastroenteropathy due to Norwalk agent). The child still has a fever and abdominal pain, but because abdominal pain is assumed with the illness, you’ll code R50.9 with the diagnosis to account for the fever.