A69.23

HCC Category Mapping

What This Code Means

This is joint inflammation and pain caused by Lyme disease, a tick-borne infection transmitted by infected deer ticks. The infection spreads to the joints and causes arthritis symptoms like swelling, stiffness, and discomfort.

Coding Tips

• •Always verify that Lyme disease has been confirmed with appropriate testing (serology or Western blot) before coding this condition, as it requires documented evidence of the infection
• •This code should only be used when arthritis is a direct manifestation of Lyme disease; if arthritis exists independently, use the appropriate arthritis code instead

Clinical Significance

Lyme arthritis is the most common late manifestation of Lyme disease, occurring weeks to months after the initial tick bite. It represents a significant chronic infectious disease burden, typically affecting large joints (especially the knee), and requires specific antibiotic therapy distinct from typical inflammatory arthritis management.

Documentation Requirements

• ✓Positive Lyme serology (two-tier testing: ELISA followed by Western blot confirmation)
• ✓Specific joint(s) involved with laterality (knee is most common)
• ✓Clinical presentation: episodic or persistent joint swelling, effusion, pain
• ✓Timeline of Lyme disease progression (early localized, early disseminated, late disseminated)
• ✓Prior treatment history and response to antibiotics

Commonly Confused Codes