Interpretation

Borrelia miyamotoi:

A positive result indicates the presence of Borrelia miyamotoi DNA and is consistent with active or recent infection. While positive results are highly specific indicators of disease, they should be correlated with symptoms and clinical findings of tick-borne relapsing fever.

Ehrlichia/Anaplasma:

Positive results indicate presence of specific DNA from Ehrlichia chaffeensis, Ehrlichia ewingii, Ehrlichia muris eauclairensis, or Anaplasma phagocytophilum and support the diagnosis of ehrlichiosis or anaplasmosis.

Negative results indicate absence of detectable DNA from any of these 4 pathogens in specimens, but it does not exclude the presence of the organism or active or recent disease.

Since DNA of E ewingii is indistinguishable from that of Ehrlichia canis by this rapid polymerase chain reaction (PCR) assay, a positive result for E ewingii/canis indicates the presence of DNA from either of these 2 organisms.

Babesia:

A positive result indicates the presence of Babesia species DNA and is consistent with active or recent infection. While positive results are highly specific indicators of disease, they should be correlated with blood smear microscopy, serological results, and clinical findings.

A negative result indicates absence of detectable DNA from Babesia species in the specimen but does not always rule out ongoing babesiosis in a seropositive person since the parasitemia may be present at a very low level or may be sporadic.

Other tests to consider in evaluating a patient presenting with an acute febrile illness following tick exposure include serologic tests for Lyme disease (Borrelia burgdorferi) and molecular detection (PCR) for ehrlichiosis/anaplasmosis. For patients past the acute stage of infection, serologic tests for these organisms should be ordered prior to PCR testing.