Borrelia burgdorferi infection (Lyme disease) has a characteristic three-stage clinical progression. The earliest and most pathognomonic skin manifestation in stage 1 is:
- A Erythema migrans — expanding annular erythematous lesion with central clearing ✓
- B Acrodermatitis chronica atrophicans (ACA)
- C Lymphocytoma — bluish-red nodule on ear lobe
- D Diffuse erythroderma with scaling at the tick bite site
Explanation
Stage 1 (early localised) Lyme disease presents 3–30 days after Ixodes tick bite with erythema migrans (EM) — a pathognomonic expanding, flat to slightly raised, annular erythematous rash with central clearing (bull's-eye pattern) at the bite site, typically >5 cm. EM is present in approximately 70–80% of US cases. Lymphocytoma (B-lymphocyte-rich inflammatory nodule) occurs in early disseminated disease (stage 2) in European Lyme. Acrodermatitis chronica atrophicans (ACA) is a late-stage skin manifestation caused by Borrelia afzelii, primarily in Europe, presenting as bluish-red atrophic skin on extremities.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.