“Lyme borreliosis is a strange disease; new information about it is regularly coming to light, yet we still do not know the answers to many questions”.
In Central Europe, it affects one in five people; according to the latest estimates, 2.5 million people are infected with it every year on our continent. Lyme borreliosis, or Lyme disease, is the most common zoonotic infection worldwide and also the most common tick-borne bacterial disease; diagnosing it poses a particular challenge for doctors.
Why is Lyme disease difficult to diagnose?
The medical challenges associated with Lyme disease are evident right from the diagnosis stage. On the one hand, in the period immediately following the initial infection – which lasts for a few weeks – a specific antibody response against the pathogen cannot yet be detected. At the same time, serological tests may still indicate an immune response even after the patient has recovered, so the detection of an immune response alone does not conclusively confirm the presence of the disease. The symptoms, on the other hand, are largely non-specific (e.g. fatigue, ‘brain fog’, random recurring pains, impaired memory) and cannot always be directly linked to the onset of the infection. Specific symptoms may go unnoticed for years or appear insignificant.
“Lyme borreliosis is a strange disease; new information about it emerges regularly, as research continually yields new scientific findings, yet we still do not know the answers to many questions,” – says Dr Klára Esztó, a dermatologist, clinical allergist and immunologist, and Lyme disease specialist, who has been treating patients with symptoms of Lyme disease for 45 years. “Lyme borreliosis can be regarded not only as a strange but also as a complex disease, caused by bacteria belonging to the Borrelia burgdorferi sensu lato group within the Borrelia genus. These are bacterial species that enter our bodies almost exclusively via tick bites and are capable of attacking any organ if they find a suitable breeding ground. Some people may never fall ill because they have a very strong immune system, whilst others may develop a serious condition.”
Don’t just be suspicious if you see a cockade-shaped rash!
Diagnosis is further complicated by the fact that, to this day, many doctors still regard only the characteristic, cockade-shaped skin lesion – erythema migrans – as clear evidence of infection. Meanwhile, we know that this appears in only 30–50 per cent of cases, and is not limited to the site of the bite. If we only investigate 30–50 per cent of infections on suspicion of Lyme disease, and serology reliably detects only 50–60 per cent of these, this means that, on average, only one in four of the 10 infected people will be referred for testing; of these, at best, only one in two will receive a positive result and, consequently, treatment.
“If there are no clearly specific skin symptoms, it depends on the doctor’s expertise and experience to make a diagnosis based on the combination of symptoms, whilst ruling out other conditions – essentially through differential diagnosis,” – says Dr Klára Esztó. “The more unusual symptoms a patient has, the more the doctor should consider this condition!”
Time is a crucial factor
As a result of the bacterium’s immunosuppressive effect and the difficulties outlined above, the serological tests currently widely available are not sufficiently reliable for diagnostic purposes. Consequently, many patients do not receive the appropriate care in time. The time factor is of paramount importance in the case of Lyme disease, as the treatability of the condition is greatly influenced by early diagnosis and the timely initiation of appropriately tailored antibiotic treatment.
In addition to serological tests, there are also so-called direct tests, which do not detect the immune system’s response but rather the bacterium itself that causes the disease. One such direct test is the Hungarian-developed DualDur, the most thoroughly tested laboratory test in Europe, which is capable of concentrating enough pathogens from a blood sample to make them visible under a microscope during the course of the disease, even in the early stages of infection.
(C) Lyme Borreliosis Foundation
