infectious diseases
Lyme Disease
Introduction
Lyme disease is a tick-transmitted infection caused by the spirocheteBorreliaspecies. Early symptoms include an erythema migrans rash, which may be followed weeks to months later by neurologic, cardiac, or joint abnormalities. Diagnosis is primarily clinical in early-stage disease, but serologic testing can help diagnose cardiac, neurologic, and rheumatologic complications that occur later in the disease. Treatment is with antibiotics such asdoxycyclineorceftriaxone. Spirochetes are distinguished by the helical shape of the bacteria. Pathogenic spirochetes includeTreponema,Leptospira, andBorrelia. BothTreponemaandLeptospiraare too thin to be seen using brightfield microscopy but are clearly seen using darkfield or phase microscopy.Borreliaare thicker and can also be stained and seen using brightfield microscopy. 