Rickettsioses
ICD-10 Codes (20)
A77A77.0A77.1A77.2A77.3A77.4A77.40A77.41A77.49A77.8A77.9A78A79A79.0A79.1A79.8A79.81A79.82A79.89A79.9Updates & Changes
FY 2026 Updates
New Codes (2)
Revised Codes (2)
Deleted Codes
No codes deleted in this range for FY 2026
Historical Changes
- •FY 2025: Routine maintenance updates with minor terminology clarifications
- •FY 2024: Enhanced specificity requirements for certain code ranges
- •FY 2023: Updated documentation guidelines for improved clarity
Upcoming Changes
- •Proposed updates pending review by Coordination and Maintenance Committee
- •Under consideration: Enhanced digital health integration codes
Implementation Guidance
- •Review all FY 2026 updates for A75-A79 codes before implementation
- •Always verify the most current codes in the ICD-10-CM manual
- •Ensure clinical documentation supports the selected diagnosis codes
- +3 more guidance items...
Range Overview
The ICD-10 code range A75-A79 is dedicated to Rickettsioses, a group of infectious diseases caused by bacteria from the Rickettsiaceae family. These diseases are usually transmitted through arthropod vectors such as ticks, fleas, and lice. The range includes codes for specific conditions like typhus fever, spotted fever, Q fever, and other rickettsioses.
Key Usage Points:
- •A75 codes are used for different forms of typhus fever.
- •A77 codes represent different types of spotted fever.
- •A78 is the specific code for Q fever.
- •A79 codes are used for other types of rickettsioses.
- •Always code for the highest level of specificity.
Coding Guidelines
When to Use:
- ✓When a patient is diagnosed with a specific form of typhus fever.
- ✓When a patient is diagnosed with a specific type of spotted fever.
- ✓When a patient is diagnosed with Q fever.
- ✓When a patient is diagnosed with other types of rickettsioses.
When NOT to Use:
- ✗When a patient is suspected of having a rickettsial disease but the diagnosis is not confirmed.
- ✗When a patient has a non-rickettsial infectious disease.
- ✗When a patient has a condition caused by a non-rickettsial bacteria.
- ✗When a patient has a condition caused by a virus.
Code Exclusions
Always verify exclusions with the latest ICD-10-CM official guidelines.
Documentation Requirements
Documentation for rickettsioses should be detailed and specific. It should clearly state the type of rickettsial disease and any associated complications or manifestations.
Clinical Information:
- •Specific type of rickettsial disease.
- •Clinical signs and symptoms.
- •Results of diagnostic tests.
- •Treatment provided.
- •Patient's response to treatment.
Supporting Evidence:
- •Laboratory test results confirming the presence of rickettsial bacteria.
- •Imaging studies if applicable.
- •Notes from the treating physician.
Good Documentation Example:
Patient diagnosed with epidemic typhus fever (A75.0) confirmed by laboratory tests. Presented with high fever, severe headache, and rash. Treated with doxycycline.
Poor Documentation Example:
Patient has fever and rash.
Common Documentation Errors:
- ⚠Not specifying the type of rickettsial disease.
- ⚠Not including supporting evidence such as laboratory test results.
- ⚠Not documenting the patient's response to treatment.
Range Statistics
Coding Complexity
Coding for rickettsioses is of medium complexity due to the need to accurately identify the specific type of disease and any associated complications. It also requires a good understanding of the clinical context and the ability to stay current with changes in the classification of rickettsial diseases.
Key Factors:
- ▸Determining the specific type of rickettsial disease.
- ▸Coding for associated complications or manifestations.
- ▸Understanding the clinical context.
- ▸Keeping up-to-date with changes in the classification of rickettsial diseases.
Specialty Focus
Rickettsioses are primarily diagnosed and treated by infectious disease specialists. However, these conditions may also be encountered by primary care physicians, emergency medicine specialists, and dermatologists.
Primary Specialties:
Clinical Scenarios:
- • Patient presenting with high fever and rash after a tick bite.
- • Patient with a history of hiking presenting with fever, headache, and muscle aches.
- • Patient with severe headache and high fever after returning from a trip to a rural area.
- • Patient presenting with a rash and history of flea exposure.
Resources & References
Several resources are available for coding rickettsioses, including the ICD-10-CM official guidelines, clinical reference books, and educational materials.
Official Guidelines:
- ICD-10-CM Official Guidelines for Coding and Reporting
- WHO ICD-10 Version: 2019
- CDC ICD-10-CM Resources
Clinical References:
- Harrison's Principles of Internal Medicine
- Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases
Educational Materials:
- AAPC ICD-10-CM Training
- AHIMA ICD-10-CM Coding Resources
Frequently Asked Questions
How do I code for a patient with a suspected but unconfirmed rickettsial disease?
If the diagnosis is not confirmed, use the code for the patient's presenting symptoms until the diagnosis is confirmed.