A22.1

HCC Category Mapping

What This Code Means

Pulmonary anthrax is a serious lung infection caused by breathing in spores from the anthrax bacterium, which can cause severe respiratory illness and pneumonia-like symptoms. This is a rare but potentially life-threatening condition that requires immediate medical treatment with antibiotics.

Coding Tips

• •Pulmonary anthrax is considered an infectious disease and may require reporting to public health authorities depending on jurisdiction; verify local reporting requirements
• •Ensure documentation clearly specifies pulmonary involvement (as opposed to cutaneous or gastrointestinal anthrax) to support accurate code selection

Clinical Significance

Pulmonary anthrax (inhalational anthrax) is the most lethal form of Bacillus anthracis infection with historically near-100% mortality if untreated. It is a CDC Category A bioterrorism agent and a national security concern. Even with aggressive treatment, mortality remains 45-90%, making early recognition critical.

Documentation Requirements

• ✓Clinical presentation consistent with inhalational anthrax (widened mediastinum on imaging, hemorrhagic pleural effusions, respiratory failure)
• ✓Laboratory confirmation — blood cultures, PCR, or anthrax-specific testing (lethal factor, protective antigen)
• ✓Chest imaging (CT preferred) showing mediastinal widening, pleural effusions, or pulmonary infiltrates
• ✓Epidemiologic investigation findings (occupational exposure, mail handling, bioterrorism assessment)
• ✓Public health notification and coordination documentation

Commonly Confused Codes