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Many approaches were made in recent years to establish urine PCR as a diagnostic tool for Lyme borreliosis, but results are contradictory. In the present study, a standardized protocol spiking urine from healthy donors with a defined amount of whole Borrelia or Borrelia DNA was established. The development of a nested real-time PCR targeting ospA enabled a highly sensitive and quantitative analysis of these samples. We show the following. (i) Storage of spiked urine samples for up to 6 months at--20 degrees C had no negative effect on spike recovery. (ii) Centrifugation of 10 ml of urine at 40,000 x g for 30 min resulted in a concentration of both spikes, i.e., whole Borrelia and DNA. (iii) The inhibition of DNA spike recovery in 48% (11 of 23 samples) of urine samples tested could be attributed to nuclease activity. This was abrogated by alkalizing the urine or by working with the samples on ice. Despite optimized conditions, analysis of urine samples of 12 patients with erythema migrans, the clinical stage considered to be associated with the highest bacterial load, revealed a positive result in only one sample. All 12 samples were negative by an alternative PCR targeting flagellin. The results of our study support doubts that urine is a suitable material for diagnosis of Lyme borreliosis.

Skin biopsies of 36 patients with erythema migrans and acrodermatitis chronica atrophicans (ACA) before therapy and those of 8 patients after therapy were examined for Borrelia burgdorferi DNA by PCR. Skin biopsies of 27 patients with dermatological diseases other than Lyme borreliosis and those of 10 healthy persons were examined as controls. Two different primer sets targeting 23S rRNA (PCR I) and 66-kDa protein (PCR II) genes were used. PCR was performed with freshly frozen tissue (FFT) and paraffin-embedded tissue (PET). For FFT specimens of erythema migrans, 73% were positive by PCR I, 79% were positive by PCR II, and 88% were positive by combining PCR I and II. For PET specimens, PCR was less sensitive (PCR I, 44%; PCR II, 52%). For FFT specimens of ACA, PCR I was positive for two of five patients and PCR II was positive for four of five patients. B. burgdorferi was cultured from 79% of the erythema migrans specimens but not from any of the ACA lesions. Elevated B. burgdorferi antibodies were detected in sera of 74% of erythema migrans patients and 100% of ACA patients. All urine samples were negative by PCR II, whereas PCR I was positive for 27%. However, hybridization of these amplicons was negative. Sequencing of three amplicons identified nonborrelial DNA. In conclusion, urine PCR is not suitable for the diagnosis of skin borreliosis. A combination of two different primer sets achieves high sensitivity with skin biopsies. In early erythema migrans infection, culture and PCR are more sensitive than serology.

Since the possibility of asymptomatic infection with Borrelia burgdorferi has been suggested by a positive serology found in healthy subjects, we hypothesized that these subjects might excrete borrelial DNA sequences in urine as happens in patients with Lyme borreliosis. We found borrelial sequences by nested PCR in the urine samples from 3 of 13 healthy B. burgdorferi antibody-positive adults but not in urine samples from 79 antibody-negative healthy controls. After therapy with doxycycline, the urine samples were repeatedly negative for B. burgdorferi DNA. We conclude that urinary excretion of borrelial DNA sequences may occur in seropositive healthy subjects during asymptomatic infection. Demonstration of such sequences in urine must be interpreted cautiously and may not necessarily prove a borrelial cause of disease.

A polymerase chain reaction (PCR) was developed for use in the identification of a 248-bp fragment of the Borrelia burgdorferi flagellin gene in urine and cerebrospinal fluid (CSF) from patients with Lyme neuroborreliosis. The specificities of the PCR products were confirmed by DNA-DNA hybridization with an internal probe. The assay had a detection limit of 10 in vitro-cultivated B. burgdorferi. The PCR assay seemed to be species wide as well as species specific, since DNA from all 21 B. burgdorferi isolates from humans tested but not from Borrelia hermsii or Treponema pallidum could be amplified. We tested 10 consecutively diagnosed patients with untreated neuroborreliosis. There was lymphocytic pleocytosis and intrathecal B. burgdorferi-specific antibody synthesis in the CSF of all patients. Urine and CSF samples were investigated by PCR before, during, and up to 8.5 months after therapy. B. burgdorferi DNA was detected in urine samples from nine patients; five patients, including two patients with chronic neuroborreliosis, were PCR positive prior to treatment, whereas urine samples from the remaining four patients obtained 3 to 6 days after the onset of therapy became PCR positive. All urine samples obtained greater than 4 weeks after therapy were negative by PCR. PCR of CSF was less sensitive, and samples from only four patients, including one with chronic neuroborreliosis, were positive. We conclude that urine is a more suitable sample source than CSF for use in B. burgdorferi DNA detection by PCR. Normalization of inflammatory CSF changes and the negative PCR results during follow-up even in patients with chronic neuroborreliosis do not point to a persistent infection. The future role of PCR as a diagnostic tool for Lyme neuroborreliosis is still uncertain.

Current diagnostic tests for Lyme disease (LD) are dependent upon the host serologic response and are insensitive early in infection and, possibly, following antibiotic therapy. We cloned a library of Borrelia burgdorferi 297 DNA and studied one clone, Ly-1, for its potential in diagnostic and pathogenic studies. Using pulsed-field electrophoresis, we demonstrated that Ly-1 is of chromosomal origin and estimated that the B. burgdorferi chromosome is approximately 1,100 kb in size. The 3.7-kb Ly-1 clone hybridizes with geographically diverse strains of B. burgdorferi. No cross hybridization occurs with DNA from human cells, Escherichia coli, Staphylococcus aureus, Clostridium difficile, or the closely related B. hermsii. We used a dot blot assay to detect 100 pg of B. burgdorferi DNA. We partially determined the nucleotide sequence of Ly-1 and used it to select and synthesize oligonucleotides for use in the polymerase chain reaction (PCR). Two different primer pairs were found to amplify DNA from nine geographically diverse isolates. We could detect 10 fg (less than 10 molecules) of B. burgdorferi or less than five spirochetes added to human urine. Finally, we were able to use the PCR to detect B. burgdorferi DNA in the urine of four of eight patients with suspected active LD (three with arthritis and one with neurologic manifestations), all of whom responded to antibiotic treatment. In contrast, those patients who were PCR negative either had inactive disease or had been appropriately treated and did not respond to additional antibiotics, and all four control urine specimens were PCR negative. We conclude that B. burgdorferi DNA can be sensitively detected by the PCR with the primers and methods we describe and that the urinary tract is a site of persistent infection in some cases of human LD, an observation of potential diagnostic and pathogenic importance.

Segments of the ospA gene of Borrelia burgdorferi were amplified by the polymerase chain reaction (PCR). Oligonucleotide primers used in the reaction flank a 309-base-pair segment within the ospA gene. After 35 cycles of amplification, the product could be detected by agarose gel electrophoresis or dot hybridization with a 32P-labeled probe. This segment was amplified in all strains of B. burgdorferi tested, but it was not detected in other bacterial species. An additional primer pair which has a broad specificity for conserved 16S rRNA sequences that are present in eubacteria amplified a 215-base-pair fragment in all organisms tested. The sensitivity of PCR for the detection of B. burgdorferi in clinical samples was evaluated by seeding blood and urine specimens with B. burgdorferi and subjecting them to amplification. We were able to detect 10 organisms per ml of blood or urine, using PCR with dot hybridization detection. DNA extraction is not required for sample preparation. Blood and urine specimens were obtained from canines with clinical and serologic evidence of Lyme disease and subjected to PCR analysis. Of 17 clinical specimens from 15 animals, one blood specimen showed reactivity in the PCR.