This is tricky situation.Some experts say in this particular case, with your physician's input, they would most likely code it a screening service, and add the diarrhea as a secondary dx. It's up to the insurance company if they will still allow the patient to access their screening benefit.
A screening colonoscopy is performed on patients that do not have any GI related symptoms such as diarrhea or rectal bleeding nor do these patients have polyps or biopsies done. Most insurance packages will cover screening colonoscopies as a part of preventative medicine.
A diagnostic colonoscopy is performed on patients when GI related symptoms are occurring such as diarrhea or rectal bleeding. Please note that you may be scheduled for a screening colonoscopy, but after the procedure it will be coded diagnostic. If polyps are found during the procedure it will be considered diagnostic NOT a screening. Most insurance companies will apply diagnostic colonoscopy charges to patient’s deductibles, copayments and co-insurance amounts.
We highly recommend that you contact your insurance carrier and find out what the coverage difference is for screening and diagnostic colonoscopies.