Diagnosing Lyme Disease and Rickettsia
A petechial rash is indicative of Rickettsia (Rocky Mountain Spotted Fever).
Tick-borne illnesses can be caused by a number of pathogens, including bacteria like Borrelia burgdorferi or rickettsia
, viruses, and protozoa. Several of these may be transmitted by a single tick, leading to a confusing number of symptoms of various infections, many of which overlap or seem to exacerbate each other. Knowing which infectious agents to test for means taking a detailed history of symptoms, often going back several months, or even years to when the first unusual symptoms occurred. It can also help to know what the ticks in a given area are infected with, demonstrating the usefulness of tick-tests carried out by some local health authorities. Specific laboratory tests do not exist for rapid diagnosis of all known tick-borne diseases and so the symptoms described by a patient are often the main source of information that a physician has to go on when prescribing treatment.
Tests for Rickettsia
Laboratory tests to confirm Rickettsia include IFA, IHA, and latex agglutination, with Lyme disease testing guidelines requiring an ELISA and Western Blot as confirmation of infection. It is easy to see, given the different testing methods used, how a Lyme disease co-infection could be missed. Some doctors experienced with Lyme disease may run a complete panel for Lyme disease and co-infections so as to ensure appropriate treatment is given in a timely fashion. Based on the patients’ symptoms they may start them on a single antibiotic regime for the suspected infection and add another antibiotic if a secondary, or even tertiary infection is confirmed.