Pathology/Lab Coding Alert

Both compliance and reimbursement can hinge on the correct assignment of ICD-9-CM codes. For Medicare and many other carriers, the diagnosis codes (ICD-9) must conform to the treatment codes (CPT) for the medical services to be reimbursed, says Laurie Castillo, MA, CPC, president of the American Association of Professional Coders, Northern Virginia Chapter and owner of Physician Coding & Compliance Consulting in Manassas, Va. But there seems to be much confusion in the coding community about how to assign the ICD9 Codes when the presenting symptoms or initial diagnosis is different from the definitive diagnosis, she continues. This dilemma is commonplace for pathologists and laboratories because they often provide the definitive diagnosis.

Ever since the Health Care Financing Administration (HCFA) instituted validation edits for ICD-9 codes in 1990, healthcare providers have had to ensure that these codes match the CPT codes to facilitate reimbursement. In this way, Medicare and other carriers are assured that medical treatment is justified by the patients condition.

However, ICD-9 codes cant be conveniently selected to justify a treatment; they have to accurately represent the patients condition and the medical documentation or else they represent fraud, advises Castillo. That comes back to the question of whether to assign ICD-9 codes on the basis of symptoms or diagnosis.

First, you have to realize that the rules are different for outpatient and inpatient services, reports Castillo.

Editor's note: We will cover the guidelines for inpatient services in a future issue of the Pathology Coding Alert.

The directions for these two groups are clearly laid out in the Official ICD-9-CM Guidelines for Coding and Reporting, she continues.

These are the only guidelines that are approved by the cooperating parties for ICD-9-CM: the American Hospital Association, American Health Information Management Association, HCFA and the National Center for Health Statistics, indicates Castillo.

Editors note: These guidelines can be found at www.cdc.gov/nchs/data/icdguide.pdf.

Guidelines for Outpatient Services

The golden rule for outpatient ICD-9 coding is to bill for the reason for the encounter, advises Castillo. If you read the outpatient guidelines, the phrase reason for the encounter/visit appears eight times, and might include diagnoses, symptoms, conditions, problems, complaints or other reasons, she continues. This is one of the main differences between inpatient and outpatient ICD-9 coding. According to the guidelines, outpatient services are to be coded this way, recognizing that diagnoses often are not established at the time of the initial encounter/visit. It may take two or more visits before the diagnosis is confirmed.

Another important rule [...]