Lyme Disease among Patients at an Ambulatory Unit in a Highly Endemic Country: Lithuania

Background and objectives: Lyme disease is the most common tick-borne infectious disease in Europe, caused by the spirocheta bacteria of Borrelia burgdorferi. Several genospecies of B. burgdorferi are pathogenic to humans. B. burgdorferi sensu stricto, which is prevalent in North America, causes reactive arthritis, whereas B. garinii and B. afzelii, common in Europe, can affect the skin, heart, or nervous system; it has been shown that the clinical symptoms of the disease may be very different. The objective of this study was to identify the baseline characteristics of Lyme disease and to elucidate the frequency of different Lyme disease syndromes in Lithuania. Materials and Methods: Patients who were diagnosed with Lyme disease during an ambulatory visit to the Center of Infectious Diseases, Vilnius University Santaros clinics, from 2014 to 2016, were enrolled in this study. A retrospective material analysis was conducted. Results: In total, 1005 patients were enrolled with the following prevalence of clinical syndromes: erythema migrans (EM), 945 (94.02%); Lyme arthritis, 32 (3.18%); neuroborreliosis, 23 (2.28%); Lyme carditis, 4 (0.39%); and acrodermatitis, 1 (0.09%). Erythema migrans was dominant among middle-aged women, with a rash appearing mainly on the lower extremities. Lyme arthritis mainly manifested among middle-aged women as an oligoarthritis, mostly affecting the knee joint. Neuroborreliosis was seen more often in middle-aged women than men and the main symptom was nervus facialis neuropathy. Lyme carditis, manifested as an atrioventricular block, with a male/female ratio of 3:1, and the median age was 51. Acrodermatitis was diagnosed in a 61-year-old woman, as a painful, red rash on the hand. Conclusions: According to the prevalence of B. garinii and B. afzelii in Europe, previously it was thought that Lyme disease presented as erythema migrans, and less frequently as neuroborreliosis; however, this study revealed that other syndromes may also be seen. In addition, we revealed that the longer it takes for erythema migrans to appear, the greater the likelihood of Lyme arthritis developing.