Name of the Condition

• Acrodermatitis chronica atrophicans
• Also known as ACA

Summary

Acrodermatitis chronica atrophicans (ACA) is a skin condition, often representing the late-stage manifestation of Lyme borreliosis. It is primarily characterized by skin changes that can become atrophic and are more common in adults.

Causes

ACA is caused by an infection with the bacterium Borrelia burgdorferi. This bacterium is transmitted to humans through tick bites, typically from the Ixodes species of ticks.

Risk Factors

Factors that might increase the risk of developing ACA include:

• Being in an area where Lyme disease is prevalent.
• Spending time in wooded or grassy areas without protective clothing.
• Lack of immediate treatment following a tick bite possibly infected with Borrelia burgdorferi.

Symptoms

Common symptoms of ACA include:

• Bluish-red discoloration of the skin, often starting on the extremities.
• Progressive skin thinning (atrophy) over time.
• Eventually, areas of the skin may become wrinkled and shiny due to atrophy.

Diagnosis

ACA is diagnosed using a combination of:

• Clinical examination of the skin.
• Patient history, especially regarding possible tick exposure.
• Serological tests to detect antibodies against Borrelia burgdorferi.

Treatment Options

• Antibiotics: Such as doxycycline or amoxicillin, are the primary treatments and are most effective when started early.
• Topical treatments: May be used to alleviate local symptoms and improve skin condition.

Prognosis and Follow-Up

• With appropriate antibiotic treatment, the symptoms of ACA may be reduced or resolved, though skin changes might improve slowly.
• Regular follow-ups are important to monitor treatment progress and manage any persistent symptoms.

Complications

If left untreated, ACA may lead to:

• Persistent skin atrophy.
• Cosmetic deformities.
• Potential secondary infections due to impaired skin integrity.

Lifestyle & Prevention

• Prevention includes measures to avoid tick bites, such as wearing protective clothing and using tick repellents.
• Early removal of ticks and prompt treatment of early Lyme disease may prevent progression to ACA.

When to Seek Professional Help

• Seek medical attention if you notice persistent skin changes, especially following a known tick bite or if living in an endemic area.

Additional Resources

• CDC Lyme Disease Information: www.cdc.gov/lyme
• American Lyme Disease Foundation: www.aldf.com

Tips for Medical Coders

• Ensure appropriate link to Lyme disease when coding ACA by using linked history or test results.
• Avoid errors by verifying the stage of Lyme disease as ACA is a late manifestation.