It seems that in recent years there has been an increasing trend in the incidence of Lyme disease in endemic areas, as well as a geographical expansion of its vector, the Ixodes ricinus tick.
How Long Does It Take To Show Signs Of Lyme Disease?
Lyme disease is characterized by various symptoms. The discomforts are very varied and affect many organs. If a person becomes infected with the Borrelia burgdorferi bacterium by means of a tick bite, a reddish and annular lesion on the skin may appear after several days or weeks; this would be the first manifestation.
In the first month of exposure to the tick, which in most cases the patient does not remember, early localized infection (first phase) occurs, which is usually manifested by nonspecific flu-like symptoms and the appearance of migratory erythema, which is a papule or macula that extends painlessly to take the form of a target with the clearer center. Since a quarter of patients do not have migratory erythema, it is not uncommon for this first stage to go unnoticed and doctors receive a patient with symptoms of an early disseminated infection (second stage), after weeks or months of exposure. This stage could be initiated, for example, as a general condition with intense discomfort, diffuse pains, headache, asthenia or new cutaneous symptoms: annular lesions smaller than migratory erythema, or the rare presence of lymphocytoma cutis (violaceous nodules, preferably in lobules, the ear or nipples).
Considering the inconstancy and clinical variability of borreliosis in this phase, it has been called “the great imitator”.
In any case, and if we exclude the almost constant fatigue/lethargy, it seems that the most relevant and frequent presentation symptoms (63%) are neurological, followed by the musculoskeletal and dermatological signs.
In Europe and Asia, the first Lyme disease neurological sign is a characteristically radicular pain, which continues with lymphocytic pleocytosis in cerebrospinal fluid (Bannwarth’s syndrome) and which is usually accompanied by cranial neuritis, particularly peripheral facial paralysis. Other rarer symptoms would be encephalitis, myelitis or multiple mononeuritis. Bilateral facial paralysis is a rare but suggestive, although not diagnostic, clinical presentation of Lyme disease.
Due to the difficulty in cultivating this microaerophilic bacterium, the diagnosis is established by the presence of migratory erythema or by a compatible clinical presentation, ideally confirmed with serological tests and supported by epidemiological data, such as the location of the case in an endemic area or the history of the sting of the tick. Lyme disease confirmation is established by serology, which can be negative in the first weeks (only 30-40% of migratory erythema will be positive in the acute phase and up to 70% in 2-4 weeks). The detection of anti-Borrelia antibodies is recommended in two stages: first, by a sensitive method such as ELISA, and more specific confirmation by Western blot. Serology, which is not adequate to distinguish active and inactive disease (can remain positive for years after healing, or negative in those partially treated), also has the problem of standardization; it is convenient, in any case, to determine IgG and IgM antibodies, and to compare two samples separated by 2-4 weeks.
It is important that the results are considered in a clinical and epidemiological context that suggests Lyme disease, and it is not appropriate to request serology for Borrelia in patients with nonspecific symptoms without suspicious history since, in addition, it can give falsely positive results in rheumatoid arthritis, systemic lupus erythematosus (SLE), systemic sclerosis, and others. It should also be remembered that a seronegative borreliosis is usually mild and attenuated.
The crop has a very low profitability due to the need for a complex procedure and specific means, as well as the small number of Borrelia in the samples.
The most specific test is the detection of spirochete DNA by PCR, which showed good sensitivity in synovial fluid or skin, although much less in blood, urine or cerebrospinal fluid (CSF).
If there is Lyme disease, it is essential to start treatment early. The earlier therapy begins, the better the chances of avoiding a serious course of the disease.