How can tick bites be diagnosed? - briefly
Diagnosis relies on visual examination for an attached tick or an expanding erythema migrans rash, followed by laboratory testing such as PCR or serologic assays to detect tick‑borne pathogens.
How can tick bites be diagnosed? - in detail
Tick exposure is confirmed by locating the arthropod on the skin. A thorough skin examination should include the scalp, neck, groin, armpits and any hidden folds. If a tick is found, note its size, engorgement level and attachment site; these factors help estimate the duration of feeding and the risk of pathogen transmission.
When the tick is removed, preserve the specimen for species identification, either by visual keys or by sending it to a reference laboratory. Species determination narrows the list of possible infections because different ticks vector distinct agents.
Diagnostic work‑up proceeds according to the clinical picture and the estimated exposure period:
- Serologic testing – enzyme‑linked immunosorbent assay (ELISA) followed by immunoblot for Borrelia burgdorferi; IgM and IgG panels for Anaplasma, Ehrlichia, Babesia, and Rickettsia as indicated.
- Polymerase chain reaction (PCR) – detection of pathogen DNA from blood, skin biopsy of the bite site, or cerebrospinal fluid when neurological symptoms are present.
- Culture – blood or tissue cultures for Borrelia or Babesia in specialized laboratories; generally reserved for cases where serology is inconclusive.
- Complete blood count and inflammatory markers – leukocytosis, thrombocytopenia, elevated C‑reactive protein may signal systemic infection.
- Imaging – magnetic resonance imaging of the brain or joints when Lyme neuroborreliosis or Lyme arthritis is suspected.
If the bite occurred less than 24 hours ago and the tick is identified as a known vector, prophylactic antibiotics (e.g., a single dose of doxycycline) may be prescribed without awaiting test results, according to current guidelines.
Follow‑up includes repeat serology at 2–4 weeks to detect seroconversion, monitoring for emerging symptoms such as fever, rash, arthralgia or neurological deficits, and reassessment of treatment efficacy. Documentation of the bite, laboratory findings and therapeutic decisions ensures accurate management and informs future preventive strategies.