No abstract

Human granulocytic anaplasmosis (HGA) has been recently recognized as an emerging tick-borne disease. Several reports indicate the presence of infection with Anaplasma phagocytophilum in Europe. Between January 1996 and December 2004, 24 adult patients with proven HGA were identified in a prospective study conducted at the Department of Infectious Diseases, University Medical Center Ljubljana, Slovenia, on the etiology of febrile illnesses occurring within 30 days after a tick bite. The diagnosis of acute HGA was established from seroconversion in 18 (75%) patients or at least a four-fold increase in antibody titers to A. phagocytophilum antigens in six (25%) patients and molecular identification of ehrlichial organisms in 15 (62.5%) patients. Clinical characteristics and laboratory findings were similar to those reported from the other European countries. All the patients had an acute febrile illness with headache, malaise, myalgia and/or arthralgia. Leukopenia was found in 16 (66.7%) patients, thrombocytopenia in 20 (83.3%), abnormal liver function test results in 23 (95.8%), elevated erythrocyte sedimentation rates in 18 (75%), and elevated concentration of C-reactive protein in 23 (95.8%). The disease course was relatively mild; none of the patients died and no long-term sequelae were found during a follow-up of one year even though only 15 (62.5%) were treated with doxycycline. At the examination one year after the first visit, 16/24 (66.7%) patients tested seropositive (> or =1 : 256) for A. phagocytophilum antibody, and two years after the first visit positive titers were still present in 10/18 (55.6%) patients.

The 14 day oral doxycycline was not inferior to the 14 day intravenous ceftriaxone in treatment of adult European patients with early disseminated Lyme borreliosis manifested as multiple EM. The frequency of non-specific symptoms in patients was similar to that in controls without a history of Lyme borreliosis.

Clinical characteristics associated with isolation of Borrelia burgdorferi sensu lato from skin have not been fully evaluated. To gain insight into predictors for a positive EM skin culture, we compared basic demographic, epidemiologic, and clinical data in 608 culture-proven and 501 culture-negative adult patients with solitary EM. A positive Borrelia spp. skin culture was associated with older age, a time interval of >2 days between tick bite and onset of the skin lesion, EM ≥5 cm in diameter, and location of the lesion on the extremities, whereas several other characteristics used as clinical case definition criteria for the diagnosis of EM (such as tick bite at the site of later EM, information on expansion of the skin lesion, central clearing) were not. A patient with a 15-cm EM lesion had almost 3-fold greater odds for a positive skin culture than patients with a 5-cm lesion. Patients with a free time interval between the tick bite and onset of EM had the same probability of a positive skin culture as those who did not recall a tick bite (OR=1.02); however, the two groups had >3-fold greater odds for EM positivity than patients who reported a tick bite with no interval between the bite and onset of the lesion. In conclusion, several yet not all clinical characteristics used in EM case definitions were associated with positive Borrelia spp. skin culture. The findings are limited to European patients with solitary EM caused predominantly by B. afzelii but may not be valid for other situations.