Clinical assessment of patients with suspected Lyme borreliosis

The aim of the study was to evaluate patients with suspected Lyme borreliosis, who were referred to the Lyme borreliosis Outpatients’ Clinic, Dept. of Infectious Diseases, University Medical Centre Ljubljana, Slovenia, for examination. All adult patients with suspected Lyme borreliosis (with the exception of those having erythema migrans) seen at our Outpatients’ Clinic by one of the authors of this report (K.O.) between January 2003 and November 2006 were included in the study. Demographic, epidemiological, and clinical data were obtained using a structured questionnaire. Patients were classified as having probable, possible, or past Lyme borreliosis, history of a tick bite or a toxic reaction after tick bite or insect bite/sting, presence of borrelial antibodies in serum without any symptoms, or another disease not attributed to borrelial infection at all. Out of 339 patients included in the study 13 (3.8%) were considered as having probable, 59 (17.4%) as possible, and 53 (15.6%) as past Lyme borreliosis; four (1.2%) patients were assessed because of a past tick bite, one (0.3%) for a past toxic reaction after an insect sting, while three (0.9%) were tested positive for Borrelia burgdorferi sensu lato but reported no complaints. Two-hundred and six (60.8%) patients were assumed to have a distinct disease not due to borrelial infection. Comparison of patients considered as having probable/possible Lyme borreliosis with those whose complaints were interpreted as being not due to borrelial infection revealed relatively few clear distinctions. In conclusion, over 60% of patients referred to and assessed for suspected Lyme borreliosis were probably having symptoms due to another disease. Only 72 out of 339 (21.2%) patients were interpreted to have probable or possible Lyme borreliosis and were recognized as candidates for antibiotic treatment.