Louse-borne relapsing fever

This code represents a systemic bacterial infection caused by Borrelia recurrentis, transmitted to humans primarily through the body louse (Pediculus humanus humanus). It is characterized by recurrent episodes of fever, headache, muscle aches, and other non-specific symptoms, interspersed with afebrile periods. The disease can be severe and potentially fatal if untreated.

Use this code when documentation confirms a diagnosis of louse-borne relapsing fever, typically based on clinical presentation, epidemiological factors (e.g., exposure in endemic areas or during outbreaks), and laboratory confirmation (e.g., spirochetes observed in blood smears). This code is appropriate for both initial and subsequent encounters related to this specific infection.

• Ensure documentation clearly specifies "louse-borne" to differentiate from other forms of relapsing fever.
• Do not confuse this with tick-borne relapsing fever, which is classified elsewhere.
• Consider co-occurring conditions such as anemia or organ involvement, and code them separately if documented.