title: Causes of febrile illnesses after a tick bite in Slovenian children.
abstract: BACKGROUND
  To establish the etiology in Slovenian children with febrile illnesses occurring after a tick bite.
  
  
  METHODS
  Eighty-six febrile patients younger than 15 years referred to our institution in 2001 with a history of a tick bite within 6 weeks before onset of the illness were included in this prospective study. Acute and convalescent serum samples were tested for the presence of antibodies to tick-borne encephalitis virus, Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Ehrlichia chaffeensis, Rickettsia conorii, Babesia microti, Bartonella henselae, Bartonella quintana and Francisella tularensis. Cerebrospinal fluid was investigated in patients in whom meningeal involvement was clinically suspected. Blood and/or cerebrospinal fluid from the patients were cultured in modified Kelly-Pettenkofer medium. PCR was performed to detect ribosomal DNA of A. phagocytophilum and E. chaffeensis.
  
  
  RESULTS
  Of 86 patients 33 (38%) were excluded because a well-defined febrile illness not associated with tick bite was established. Tick-borne illness was diagnosed in 28 (53%) of the 53 remaining patients. The most common diagnosis was tick-borne encephalitis (64%), followed by Lyme borreliosis (46%), human monocytic ehrlichiosis and human granulocytic ehrlichiosis (serologic evidence of infection in 9 and 4%, respectively). In 6 (21%) patients there was evidence for infection with more than 1 tick-borne agent.
  
  
  CONCLUSIONS
  Tick-borne illness was established in 53% of the patients younger than 15 years presenting with febrile illness occurring within 6 weeks after a tick bite. The most common identified illnesses were tick-borne encephalitis and Lyme borreliosis.
authors.affiliation: Department of Infectious Diseases, University Medical Centre Ljubljana, Slovenia. maja.arnez@kclj.si
authors.forename: Maja
authors.initials: M
authors.lastname: Arnez
authors.forename: Tatajana
authors.initials: T
authors.lastname: Luznik-Bufon
authors.forename: Tatajana
authors.initials: T
authors.lastname: Avsic-Zupanc
authors.forename: Eva
authors.initials: E
authors.lastname: Ruzic-Sabljic
authors.forename: Miroslav
authors.initials: M
authors.lastname: Petrovec
authors.forename: Stanka
authors.initials: S
authors.lastname: Lotric-Furlan
authors.forename: Franc
authors.initials: F
authors.lastname: Strle
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D000818:Animals; D001733:Bites and Stings / Q000150:complications*; D002648:Child; D002675:Child, Preschool; D004675:Encephalitis, Tick-Borne / Q000175:diagnosis* / Q000453:epidemiology*; D005334:Fever / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015994:Incidence; D007223:Infant; D011336:Probability; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment; D012494:Sampling Studies; D012720:Severity of Illness Index; D017678:Sex Distribution; D017524:Slovenia / Q000453:epidemiology; D018709:Statistics, Nonparametric; D017282:Tick-Borne Diseases / Q000175:diagnosis* / Q000453:epidemiology*; D013987:Ticks