Lyme borreliosis and other nonvenereal spirochetal infections

Abstract

Lyme borreliosis, leptospirosis, and relapsing fever are multisystemic zoonoses caused by spirochetes. The causative bacteria are Borrelia burgdorferi sensu lato (transmission by Ixodes ticks), Leptospira interrogans (infection in water and damp soil after excretion by infected animals), and relapsing fever borreliae transmitted by ticks (endemic relapsing fever) or lice (epidemic relapsing fever). In Lyme borreliosis, the skin is the organ most frequently affected (>85%). There are three forms of dermatoborrelioses: erythema migrans, Borrelia lymphocytoma, and acrodermatitis chronica atrophicans. In leptospirosis and relapsing fever, 50-60% of patients develop nonspecific macular/papular exanthemas, sometimes with a petechial character. Leptospirosis and relapsing fever can occur in phases or episodes of high fever and cause severe symptoms in numerous organs. In the diagnosis of the latter two, direct pathogen detection is of key importance. In Lyme borreliosis, serology is routinely used, but the possibility of false-positive or false-negative findings must be kept in mind. Oral doxycycline is the drug of choice for the treatment of Lyme borreliosis, mild leptospirosis, and relapsing fever. Severe leptospirosis and relapsing fever are treated intravenously with benzylpenicillin.