Detection of specific Borrelia DNA by polymerase chain reaction (PCR) in urine of patients with Lyme disease
Abstract
Objective: In this study we were proving the Borrelia-specific nucleic acid in urine of patients with neural and articular forms of Lyme disease (LD). We attempted to assess the benefit of this method in diagnostics of LD and the relation of PCR examination results to the type of clinical affection and effect of antibiotic therapy.
Methods: In urine of 34 patients, Borrelia DNA was proved by means of PCR. We used 2 sets of primers: one complementary to the section of chromosomal gene encoding 16S rDNA, the other complementary to plasmide gene encoding protein OspC.
Samples of material were retrieved at the start of therapy, at its end, and 3 months after the end of hospitalization. Results: Of patients examined at the start of therapy, 21 (61%) were PCR positive; at the end of treatment, PCR was positive in 19 (56%) patients, and 3 months after treatment in 2 individuals (8%).
In the group of patients with neural form of LD, 14 and 9 had signs of meningopolyradiculoneuritis and meningoencefalitis respectively. Of patients with meningopolyradiculoneuritis tested at the beginning of hospitalization, 9 were positive; at the end of hospitalization they were 4.
On follow-up after 3 months, Borrelia DNA was not found in a single patient. In the meningoencefalitis group, 4 patients were PCR positive at the start of therapy.
At its end, 8 subjects in this group were PCR positive; 3 months later, Borrelia nucleic acid was found in 1 subject. Of 6 patients with articular form of LD, a half were PCR positive at the start of hospitalization; by its end, Borrelia nucleic acid was present in 5 subjects; and on follow-up it was not found in any patient.
The percentage of positive patients was higher in acute forms of LD (77%) as compared to chronical symptoms (57%). Conclusion: The study confirmed urine as a suitable material for diagnostic purposes in LD.
Our PCR method brings considerable amount of positive results in LD patients diagnosed on the basis of "classical methods". Our method is sufficiently sensitive, however it is not suitable as a solitary diagnostic tool.
Therefore it is necessary to employ all diagnostic methods simultaneously so that the efficiency in establishing the diagnosis is maximal.