Pediatric Coding Alert

Reader Questions:

Know When Presenting Problems Don’t Equal Principal Diagnosis

Published on Wed Aug 09, 2023

Question: A patient presented with abdominal pain, nausea with vomiting, and diarrhea. The provider did a thorough exam and diagnosed the patient with unspecified infectious gastroenteritis. I submitted the symptoms in order of severity, so the nausea with vomiting was first, followed by the diarrhea, then the abdominal pain, then the gastroenteritis. The claim was denied. Why?

AAPC Forum Participant

Answer: There are a couple possible reasons why this was denied. One is sequencing.

According to the ICD-10 Official Guidelines, the principal diagnosis should be sequenced first. The patient presented with a series of symptoms, but the provider determined the cause of those symptoms to be gastroenteritis, so that is what should be sequenced first. ICD-10 Official Guidelines Section II.A explains: “Codes for symptoms, signs, and ill-defined conditions from Chapter 18 are not to be used as principal diagnosis when a related definitive diagnosis has been established.” This means that you should first report the gastroenteritis, possibly as A09 (Infectious gastroenteritis and colitis, unspecified). The rest of the symptoms should then be reported in order of severity to help offer a comprehensive picture of the patient’s condition.

If A09 is the best code to use for this encounter, beware the Excludes1 note, which says not to report A09 with Diarrhea NOS. That means you can’t report A09 and R19.7 (Diarrhea, unspecified) together. Also, 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.”

All these things considered, your new claim should end up looking something like this: