Pathology/Lab Coding Alert

 "Because most of us have not dealt with this disease before, a primer on both diagnosis and procedure coding is in order," says Laurie Castillo, MA, CPC, CPC-H, CCS-P, member of the National Advisory Board of the American Academy of Professional Coders and president of Physician Coding and Compliance Consulting in Virginia. "In anthrax cases, proper coding is not just a matter of reimbursement it is also a matter of correctly reporting for public-health purposes," she says.

Diagnosis Codes Differ for Patients

Caused by infection with Bacillus anthracis, anthrax has historically been a rare illness transmitted from infected animals to humans and is not communicable from one person to another. The anthrax organism forms a spore with a protective coating that allows it to survive in the environment for years. The spore is transmitted to humans by three routes, which account for the three clinical presentations of the disease.

Inhalational Anthrax
 
Caused by inhalation of anthrax spores, the illness presents with symptoms characteristic of viral respiratory illness. Characterized by x-ray evidence of mediastinal widening, the illness typically progresses to respiratory failure and shock, often leading to death. Using ICD9 Codes, you should report inhalational anthrax as 022.1 (pulmonary anthrax). "Meningitis frequently develops in association with this form and should be reported as the secondary diagnosis using 022.8 (other specified manifestations of anthrax)," Castillo says.

Cutaneous Anthrax
 
Caused by skin contact with the spores, cutaneous anthrax is characterized by a vesicular lesion that evolves to a depressed black area called an eschar. This form is reported as 022.0 (cutaneous anthrax). 

Gastrointestinal Anthrax
 
Caused by ingestion of undercooked, contaminated meat, gastrointestinal anthrax presents as severe abdominal pain, often progressing to bloody diarrhea, pharynx lesions and fever. Report this form as 022.2 (gastrointestinal anthrax). "Septicemia often develops with this type of anthrax infection and should be reported as the secondary diagnosis (022.3 anthrax septicemia)," Castillo says.
 
"Regardless of the route of infection, if the exposure to the organism comes through intentional rather than natural means, an E code should also be reported," Castillo says. "Although they are never the primary diagnosis, the E codes provide supplementary classification of external causes of injury and poisoning and are important for epidemiological purposes. Intentional poisoning with B. anthracis spores would be reported as E962.1 (assault by poisoning; other solid and liquid substances)."
 
The preceding codes should be used only for symptomatic patients with confirmed cases of  anthrax. For testing of asymptomatic individuals who have been exposed to B. anthracis, report V01.8 (contact with or exposure to other communicable diseases). According to a CMS memorandum, if exposure is confirmed (e.g., positive nasal swab), and the patient is to undergo prophylactic antibiotic treatment, report codes 795.3 (nonspecific positive culture findings) and V07.39 (other prophylactic chemotherapy).
 
Any of these diagnoses would support antibiotic treatment, which has varying success depending on the type and stage of the disease.