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Internal Medicine Coding Alert

Influenza Coding:

Flu Vaccine Coding Becomes Easier with These Expert Tips

From immunizations to diagnoses, get the lowdown on flu patients.

It’s that time of year again—when parents present to the office requesting flu shots for their children or evaluations of possible flu diagnoses. Although some influenza visits are fairly straightforward, chances are strong that you’ll have a few questions about how to appropriately collect for your flu shot and flu diagnosis services. The following four tips can help you eliminate payment woes before they begin.

Tip 1: Two Strains Could Equal Dual Codes

Performing a flu test is standard practice for internists, but when you have to administer two tests on the same date, your coding can get tricky. If you perform a rapid flu test for strains A and B at the same visit and the assays provide two separate results (i.e., one result for influenza virus A and another result for influenza virus B), it would be appropriate and many insurers will allow you to report 87804 (Infectious agent antigen detection by immunoassay with direct optical observation; influenza) twice. “When two units of code 87804 are submitted, modifier 59 (Distinct Procedural Service) may be appended to the second unit to indicate that the two results represent separate services (e.g., 87804 and 87804-59),” says an expert.

Some state Medicaid programs require you to follow Medicare modifier guidelines and append modifier QW (CLIA-waived test) to 87804. To keep coding uniform, many practices use modifier QW regardless of payer.

Therefore, if you use a product that differentiates between influenza A and B and the physician documents both results, you should report 87804 twice or put “2” in the units of service box on the claim form, whichever the payer requires or recognizes. For payers that do not automatically recognize two units of 87804 and deny the second charge as a duplicate, use modifier 59 (Distinct procedural service) on the second 87804 entry. For example, you might report 87804-QW with one unit and 87804-QW-59 for the second unit to these insurers.

Tip 2: E/M with Flu Shot Requires Modifier 25

Although most of your flu shot visits involve just a few minutes of the doctor’s time, you’ll also experience scenarios when the doctor has to perform a separate, complete E/M visit in addition to the flu shot. In these cases, a modifier will be your friend.

Here’s why: According to Correct Coding Initiative (CCI) edits, E/M office or inpatient codes are bundled into the vaccine administration codes 90460, 90471 and 90473.

The modifier indicator for most of these bundles is “1,” which indicates that you can separate the codes using an appropriate modifier such as 25 (Significant, separately identifiable evaluation and management service by the same physician or other qualified health care professional on the same day of the procedure or other service). However, the exception to this rule is code 99211. CCI edits won’t allow you to report 99211 for the same patient on the same date as a vaccine administration.

To support the medical necessity of the vaccine, you will need to report the ICD-9 code V04.81 (Need for prophylactic vaccination and inoculation against other viral diseases; influenza). If you are using ICD-10 codes, you will have to use Z23 (Encounter for immunization) instead of V04.81.

Tip 3: Half-Dose of Vaccine May Require Second Visit

When your physician administers a low dose of the flu vaccine, you’ll face several options for coding the claim. Which one you choose could just come down to the patient’s age and the reason for the decreased dosage.

Younger children (under the age of three) typically get what could be considered a half dose of the vaccine, but there are codes specifically created for that purpose. For instance, 90655 (Influenza virus vaccine, trivalent, split virus, preservative free, when administered to children 6-35 months of age, for intramuscular use) is one such vaccine. The child will get a booster one or two months later.

If, however, the child is older than three and your internist administers a half dose, you should bill a full dose only once—either on the first visit or the second one—but don’t bill twice.

Tip 4: Look to J10 and J11 for Flu Dx in ICD-10-CM

You may have the ICD-9 codes for influenza committed to memory, but like all of your other diagnosis codes, you’ll have to replace them with dates of service on or after Oct. 1, when ICD-10 goes into effect.

Current way: When reporting a diagnosis of influenza, you currently start with 487 (Influenza caused by unspecified influenza virus) and, depending on symptoms and other manifestations, apply a 4th digit as follows:

  • 487.0 -- Influenza with pneumonia (It is essential to identify the type of pneumonia using an additional code)
  • 487.1 -- Influenza with other respiratory manifestations (such as laryngitis, pharyngitis, or other, acute upper respiratory infections)
  • 487.8 -- Influenza with other manifestations (such as encephalopathy or gastrointestinal symptoms)

If you know the influenza is due to certain identified influenza viruses, you may need to look at the 488 series in ICD-9. The 4th digit categories in this series are:

  • 488.0x – Influenza due to identified avian influenza virus
  • 488.1x – Influenza due to identified 2009 H1N1 influenza virus
  • 488.8x – Influenza due to novel influenza A

The fifth digit options in each of these categories are the same, and they generally parallel the fourth digits in the 487 series, namely:

  • 1 – with pneumonia
  • 2 – with other respiratory manifestations
  • 9 – with other manifestations

ICD-10: When ICD-10 goes into effect, 487 under ICD-9 may end being reported under either J10 (Influenza due to other identified influenza virus) or J11 (Influenza due to unidentified influenza virus), depending on whether the “unspecified” virus is an “other identified” or “unidentified” virus. As with ICD-9, both J10 and J11 further expand into a fourth digit classification based on the presence or absence of pneumonia, other respiratory manifestations (such as laryngitis, pharyngitis, and upper respiratory infections), gastrointestinal manifestations, or other manifestations such as encephalopathy, myocarditis, or otitis media.

For example, J10 under ICD-10 expands into the following four codes using a fourth digit expansion:

  • J10.0 (Influenza due to other identified influenza virus with pneumonia)
  • J10.1 (Influenza due to other identified influenza virus with other respiratory manifestations)
  • J10.2 (Influenza due to other identified influenza virus with gastrointestinal manifestations)
  • J10.8 (Influenza due to other identified influenza virus with other manifestations)

J10.0 further expands into the following three codes using a 5th digit expansion based on the type of pneumonia involved:

  • J10.00 (Influenza due to other identified influenza virus with unspecified type of pneumonia)
  • J10.01 (Influenza due to other identified influenza virus with the same other identified influenza virus pneumonia)
  • J10.08 (Influenza due to other identified influenza virus with other specified pneumonia) (Code also other specified type of pneumonia)

J10.8 further expands into the following four codes using a 5th digit expansion based on the type of manifestation:

  • J10.81 (Influenza due to other identified influenza virus with encephalopathy)
  • J10.82 (Influenza due to other identified influenza virus with myocarditis)
  • J10.83 (Influenza due to other identified influenza virus with otitis media)
  • J10.89 (Influenza due to other identified influenza virus with other manifestations).

Red flag: Do not use the J10 series unless the physician has definitively identified the type of influenza virus.  If it is not identified, use the J11 series. The J11 series also expands using a fourth digit expansion into four codes while J11.0 and J11.8 expand using a fifth digit expansion, similar to the expansion of J10.0 and J10.8 mentioned above.

The 488 series in ICD-9 is traceable to J09 in ICD-10. There are four codes in that category:

  • J09.X1 (Influenza due to identified novel influenza A virus with pneumonia)
  • J09.X2 (Influenza due to identified novel influenza A virus with other respiratory manifestations)
  • J09.X3 (Influenza due to identified novel influenza A virus with gastrointestinal manifestations)
  • J09.X9 (Influenza due to identified novel influenza A virus with other manifestations)