ED Coding and Reimbursement Alert

If the physician is presuming H1N1, leave 488.1 off the claim.

Diagnosis coding for patients who definitely have H1N1 influenza is easy enough: You now have 488.1 to represent patients with the condition.

Problem: A patient is diagnosed with "possible H1N1," but the ED does not have the lab work to confirm it. Should the coder use 488.1 (Influenza due to identified novel H1N1 influenza)? Not necessarily. The 2010 ICD-9 coding guidelines instruct you to code only confirmed cases of novel H1N1 influenza virus (H1N1 or swine flu, code 488.1).

"This is an exception to the hospital inpatient guidelines (Section II, H) (Uncertain Diagnosis)," states the 2009 ICDCM Official Guidelines for Coding and Reporting (www.cdc.gov/nchs/data/icd9/icdguide09.pdf). In cases where the diagnosis has not been confirmed by either laboratory testing or the physician's clinical certainty, then a code from the 487.x series is more appropriate.

Rule: Coding should be based on the provider's diagnostic statement that the patient has novel H1N1 (H1N1 or swine flu) influenza. "In this context, 'confirmation' does not require documentation of positive laboratory testing specific for novel H1N1 influenza," according to the guidelines for assigning 488.1 in the ICD-9 2010 manual.

If the provider records "suspected or possible or probable novel H1N1 influenza (H1N1 or swine flu)," do not assign 488.1. Instead, you should use the appropriate influenza code from category 487.x, instructs Michael Granovsky MD, CPC, FACEP, president of Medical Reimbursement Systems Inc. (MRSI), an ED billing company in Woburn, Mass.

Use 487.x for unspecified influenza cases, and 488.x to more "accurately report an identified viral strain, such as 488.1 for an identified H1N1 infection," according to Granovsky.

Some practices do not have the testing available, so the physician might not be comfortable stating that that the patient has H1N1 influenza. You would then not be able to code the condition as 488.1.

Do this: Since influenza A and B symptoms are nearly identical to the H1N1 influenza strain, consider a diagnosis of H1N1 only when other cases have been diagnosed in the area, suggests Philip Marcus, MD, at the St. Francis Hospital Heart Center in Roslyn, N.Y.

"At the present time, there are no easy ways to decide which strain of influenza is responsible for an individual infection. In fact, with the recent outbreak of H1N1 infection, most of the presumed cases were indeed negative when specifically tested for H1N1 antigen," Marcus says.

Best bet: Talk to your physicians about their comfort reaching a specific diagnosis in the absence of laboratory testing.

Example: A patient reports to the ED with flu-like symptoms. After an E/M service, the physician diagnoses "possible swine flu," and prescribes an antiviral medication. On the claim, you would report the following:

• 99283 (Emergency department visit for the evaluation and management of a patient, which requires these 3 key components: an expanded problem focused history; an expanded problem focused examination; and medical decision making of moderate complexity ...). for the E/M

• 487.1 (Influenza; with other respiratory manifestations) appended to 99283 to represent the flu.