Modifiers are always little tricky to use. The most interesting modifier to use is 59 or X{EPSU} modifiers. Medical coders are always in double mind while using X-modifiers. While we have discussed about E/M modifiers, 26 & TC modifiers etc, but still coders have confusion while using modifiers.
Now, if we talk about modifier 91 and 59 modifier, both are used for reporting lab testing procedures. But, in most of the scenarios the coders don’t understand the use of correct modifier (59 or 91) with the procedure codes. Today we will discuss and clear our confusion about these modifiers.
There are two modifiers used for facility reporting for lab testing: modifier -91 and -59. There is often confusion over which modifier to use when reporting multiple units that require a modifier.
As a rule of thumb, when a test is repeated at a later time the same day with a separate specimen draw, modifier -91 would be reported to avoid a NCCI edit and a denial of payment. Of course the retesting would need to follow the rules of medical necessity.
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Definition of modifier 91 & 59
Modifier -91 is appended for repeat clinical diagnostic laboratory tests performed on the same date. Modifier -91 is not to be used for procedures repeated to verify results or due to equipment failure or specimen inadequacy.
While 59 is used for differentiating two procedures while cannot be billed together on same day. But, 59 modifier is now expanded in 4 different categories on X-{EPSU} most. You can learn about the advance coding guide for X-modifiers here. Below are the definition of X-modifiers.
- XE, separate encounter—A service that is distinct because it occurred during a separate encounter
- -XS, separate structure—A service that is distinct because it was performed on a separate organ/structure
- -XP, separate practitioner—A service that is distinct because it was performed by a different practitioner
- -XU, unusual non-overlapping service—The use of a service that is distinct because it does not overlap usual components of the main service
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Use of Modifier 91 vs 59
When a comprehensive metabolic panel (80053) is performed for a patient and the results show a low potassium level. The physician orders infusion therapy to correct the condition. After the therapy (on the same day) the physician orders a second potassium level study (84132). Because the first potassium study was a component of the original comprehensive metabolic panel, a modifier -91 must be reported with the repeat test (84132) to avoid an edit and a denial of payment.
84132 Potassium; serum, plasma or whole blood
84132 -91 Potassium; serum, plasma or whole blood
Similarly if a blood glucose test is done on a patient and blood glucose is repeated, the laboratory would need to add modifier -91 to all glucose tests after the initial tests to receive payment for all subsequent tests. Documentation should clearly support for appending the 91 modifier.
When a patient has two infected wounds that are swabbed for aerobic bacterial cultures (87071). These specimens were collected at the same time from different locations. Modifier -59 would be reported with one of the CPT codes to show that it was a separate and distinct study.
When two specimens are collected at the same time from different sites on the body (e.g., polyps collected during a colonoscopy for pathology study), they would be reported with a modifier -59.
Hi, In your example above you state that modifier 91 would be use used on 84132, if done later after 80053. But them you have listed 84132, 84132-91. I understand that 84132 is included in 80053, but the test CPT codes are different, so why would you use 91 on 84132 with 80053 instead of 59? I could see if two 84132 were performed, but not 80053 and 84132. All of the MAC’s examples say multiples of the same codes.
Hi Donisha,
Thank you commenting on my blog…to answer you query regarding coding 80053 and 84132 together. If 80053 (comprehensive metabolic panel) is done and after this lab exam, still their is a medical necessary to perform 84132 ((potassium; serum, plasma or whole blood)) then you can both the procedure with a modifier to the low RVU CPT code. The documentation should clearly support for performing the exam 84132. And if both the exam are perfromed on different DOS then you can code both of them without a modifier. Hope this clears you doubt for first scenario.
The second one is simple if any laboratory procedure (CPT code 84132) is performed on same day the second exam should be reported with 91 modifier for repeat lab procedure.
To bypass the NCCI edit in 3M, you can either use 59, X modifier or 91 with CPT codes to get it paid.
What about 99213 with 94664-59 and 94761-59 No one ever pays for the 94761. Would an X modifier be better?
as per NCCI edit, 94664 and 94761 are the comprehensive procedures, hence the 59 or X modifier will be given to 99213 if coded with any of these CPT codes…please check the NCCI edits before assigning any modifier because if modifier is assigned to wrong procedure code the claim will be denied.