Part B Insider (Multispecialty) Coding Alert

Differences among 45378, G0105 and G0121 can be tricky

Keeping straight the differences among diagnostic (45378), high-risk screening ( G0105 ) and non-high-risk screening (G0121) colonoscopies can be a nightmare.
 
In an effort to keep providers on the right track, Part B carrier Cahaba GBA published examples of different circumstances in which you'd bill each code.
 
1. A patient comes in who is asymptomatic and not at high risk for colorectal cancer. During the colonoscopy, the physician makes an incidental finding that the patient has diverticuli. You should still bill this as G0121.
 
2. An asymptomatic patient with a family history of colorectal cancer comes in for a colonoscopy. The physician makes the incidental finding of diverticuli. In this case, you should bill G0105.
 
3. A patient who is symptomatic for gastro-intestinal complaints comes in for a colonoscopy, which detects the diverticuli. Because the patient had symptoms, you should code this as 45378.
 
In the above examples, the dividing line between screening and diagnostic colonoscopies is the presence of symptoms of a gastro-intestinal complaint. But Cahaba also quotes from its own policy: "If during the course of the screening colonoscopy, a lesion or growth is detected which results in a biopsy or removal of a growth, the appropriate diagnostic procedure classified as a colonoscopy with biopsy or removal should be billed and paid rather than HCPCS codes G0105 or G0121."
 
Most of the inflammatory bowel patients who come to Commonwealth Gastoenterology Associates in Lexington, Ky., require a biopsy in addition to a colonoscopy, says coder Stacy Maloney. With a biopsy, usually it's easy to bill for a diagnostic colonoscopy in any case.
 
The physician will use a biopsy to gather more information on the "microscopic pathology. If they don't know whether it's Crohn's or ulcerative colitis, a lot of the times the biopsy will give them more information," Maloney says. Or else the physician will use the biopsy to see how the patient is doing on her current medication.
 
If the patient isn't also receiving a biopsy, then Maloney will bill G0105 for a screening colonoscopy, with a diagnosis of V12.79 (Other digestive diseases) for the high-risk family history. 
 
Some patients may require surveillance biopsies every two years, such as patients with ulcerative colitis or a history of cancer. Some coders regard colonoscopies with surveillance biopsies as screenings, but these are actually diagnostic. You would use 45380 (Diagnostic colonoscopy; with biopsy) with these procedures, Pohlig says.
 
"The difference between surveillance and screening is a very fine line," she adds.
 
If a patient has already had cancer, he's allowed to have a follow-up surveillance colonoscopy within one year and then more surveillance colonoscopies every three to five years afterward, Pohlig says.