Lyme borreliosis is a multisystem
infectious disease caused by tick-transmitted spirochetes of the Borrelia burgdorferi sensu lato complex. The three characteristic cutaneous manifestations are
erythema migrans, borrelial
lymphocytoma, and
acrodermatitis chronica atrophicans.
Erythema migrans occurs in acute
Lyme borreliosis,
lymphocytoma is a subacute lesion, and
acrodermatitis is the typical manifestation of late
Lyme borreliosis. Clinical appearances of
erythema migrans and
lymphocytoma (when located on the ear or breast) are characteristic, whereas
acrodermatitis is often confused with vascular conditions. The diagnosis of
erythema migrans is made clinically. Serologic analyses often yield false-negative results and are not required for the diagnosis. However, serologic proof of the diagnosis in
lymphocytoma (approximately 90% positive) and
acrodermatitis (100% positive) is mandatory. Histopathologic examination often adds substantial information in patients with
skin manifestations of
Lyme borreliosis and is recommended in clinically (and serologically) undecided cases of
erythema migrans or
lymphocytoma and is obligatory in
acrodermatitis. Polymerase chain reaction for Borrelia-specific
DNA (rather than culture of the spirochete) and immunohistochemical investigations (
lymphocytoma) are sometimes necessary adjuncts for the diagnosis. Antibacterial treatment is necessary in all patients to eliminate the spirochete, cure current disease, and prevent late sequelae. Oral
doxycycline, also effective against
coinfection with Anaplasma phagocytophilum, is the mainstay of
therapy of cutaneous manifestations of
Lyme borreliosis. Other first-line antibacterials are
amoxicillin and
cefuroxime axetil.
Erythema migrans is treated for 2 weeks,
lymphocytoma for 3-4 weeks, and
acrodermatitis for at least 4 weeks.