Clinical And Pathogenic Analysis Of Sentinel Hospital-based Lyme Borreliosis

Lyme borreliosis is a tick-borne disease caused by Borrelia burgdorferi sensu lato. The main clinical symptoms include erythema migrans, Lyme neuritis, Lyme carditis and Lyme arthritis. The genospeices identified in the ticks and major reservoirs of borrelia in China are different from those in Europe and North American. Different Borrelia burgdorferi sensu lato (B. burgdorferi) genospecies are strongly associated with clinical manifestation and signs of Lyme borreliosis (LB) However, the clinical characteristics and genospecies of LB in China are still unclear. In order to understand the clinical and pathogenic characteristics of LB in China, the study was carried out in Mudanjiang Forestry Central Hospital from2010to2011by survey investigation and laboratory methods.According to clinical diagnosis of LB, patients with erythema migrans (EM) were included. Standardized questionnaire and medical records reviewing were used to collect information. Specific PCR was used to identify genospecies from blood samples and skin samples from patients who had EM and disseminated symptoms.A total of265patients had erythema migrans (EM). In comparison with patients from Europe and United States, EM in our patients developed earlier and smaller, with less central clearing (P<0.001) and localized pruritus or pain (P<0.01) but more ulceration or vesicles (P<0.05). EM patients had less severe systemic symptoms, arthralgia or swelling joint, and lymphadenopathy (P<0.001each). A total of55blood samples were collected from patients with EM and disseminated symptoms. B. burgdorferi DNA was detected from15blood samples, including11(76%) B. garinii,3(16%) B. afzelii, and1(8%) B. valaisiana-related (B. yangtze. sp.nov). All3skin lesions were positive for B. garinii. Phylogenetic analysis showed that the sequences of5S-23SrRNA, flagellin and outer surface protein C (OspC) coding genes were closest to the responding ones from ticks and rodents in China. In conclusion, the different EM features and clinical presentations may be derived from the different predominated genospecies in China, Europe and United States. Three B. burgdorferi genospecies (B. garinii, B. afzelii, B. valaisiana-related), with B. garinii as predominated strains, caused LB in China and all induced EM. We first reported one LB case caused by B. valaisiana-related and highlighted the pathogenic potential of this bacterium to human. Thus, it is critical to develop domestically clinical and serological diagnostic criteria in China.