Application of drug testing using exhaled breath for compliance monitoring of drug addicts in treatment.

AIM: Exhaled breath has recently been identified as a possible matrix for drug testing. This study explored the potential of this new method for compliance monitoring of patients being treated for dependence disorders. METHODS: Outpatients in treatment programs were recruited for this study. Urine was collected as part of clinical routine and a breath sample was collected in parallel together with a questionnaire about their views of the testing procedure. Urine was analyzed for amphetamines, benzodiazepines, cannabis, cocaine, buprenorphine, methadone and opiates using CEDIA immunochemical screening and mass spectrometry confirmation. The exhaled breath was collected using the SensAbues device and analyzed by mass spectrometry for amphetamine, methamphetamine, diazepam, oxazepam, tetrahydrocannabinol, cocaine, benzoylecgonine, buprenorphine, methadone, morphine, codeine and 6-acetylmorphine. RESULTS: A total of 122 cases with parallel urine and breath samples were collected; 34 of these were negative both in urine and breath. Out of 88 cases with positive urine samples 51 (58%) were also positive in breath. Among the patients on methadone treatment, all were positive for methadone in urine and 83% were positive in breath. Among patients in treatment with buprenorphine, 92% were positive in urine and among those 80% were also positive in breath. The questionnaire response documented that in general, patients accepted drug testing well and that the breath sampling procedure was preferred. CONCLUSION: Compliance testing for the intake of prescribed and unprescribed drugs among patients in treatment for dependence disorders using the exhaled breath sampling technique is a viable method and deserves future attention.

Laboratory and clinical evaluation of on-site urine drug testing.

AIM: Products for on-site urine drug testing offer the possibility to perform screening for drugs of abuse directly at the point-of-care. This is a well-established routine in emergency and dependency clinics but further evaluation of performance is needed due to inherent limitations with the available products. METHODS: Urine drug testing by an on-site product was compared with routine laboratory methods. First, on-site testing was performed at the laboratory in addition to the routine method. Second, the on-site testing was performed at a dependency clinic and urine samples were subsequently sent to the laboratory for additional analytical investigation. RESULTS: The on-site testing products did not perform with assigned cut-off levels. The subjective reading between the presence of a spot (i.e. negative test result) being present or no spot (positive result) was difficult in 3.2% of the cases, and occurred for all parameters. The tests performed more accurately in drug negative samples (specificity 96%) but less accurately for detecting positives (sensitivity 79%). Of all incorrect results by the on-site test the proportion of false negatives was 42%. The overall agreement between on-site and laboratory testing was 95% in the laboratory study and 98% in the clinical study. CONCLUSION: Although a high degree of agreement was observed between on-site and routine laboratory urine drug testing, the performance of on-site testing was not acceptable due to significant number of false negative results. The limited sensitivity of on-site testing compared to laboratory testing reduces the applicability of these tests.

Diagnostic probability classification in suspected borreliosis by a novel Borrelia C6-peptide IgG1- subclass antibody test.

The tick-borne multisystemic infection caused by Borrelia burgdorferi sensu lato, Lyme borreliosis, or Lyme disease, occurring in temperate regions of the northern hemisphere, continues to spread geographically with the expanding tick population. Despite the rising perceived risk of infection in the population, the clinical diagnosis of Borrelia infection is not always obvious and the most important laboratory test, antibody detection, has limited accuracy in diagnosing active disease. According to international guidelines, the primary serology test, which has a high sensitivity-low specificity, should, be verified using a high specificity confirmation test to improve the specificity. However, this enhancement in specificity comes at the cost of lower sensitivity. This two-step procedure is often omitted in everyday clinical practice. An optimal primary test would be one where no secondary tests for confirmation would be necessary. In the present study, the performance of a novel assay for quantitating IgG1-subclass antibodies to Borrelia C6-peptide was compared to a commercial reference assay of total IgG and IgM antibodies to Borrelia C6-peptide in the setting of a high endemic area for borreliosis. A derivation study on a retrospective clinical material was performed to compare the performance parameters and assess the discriminatory properties of the assays, followed by a prospective validation study. The IgG1-antibody assay achieved comparable summary performance parameters to those of the reference assay. The sensitivity was almost 100% while the specificity was about 50%. In a high-endemic setting, characterized by high background seropositivity of about 50% and disease prevalence of approximately 10%, antibody tests are unable to rule-in active Borrelia infection. The rule-out assessment of the methods revealed that of 1000 patients, 7 - 54 with negative results based on the reference method could have an active Borrelia infection. Such uncertainty was not found for the index test and may help improve the risk classification of patients.

Evaluation of a new simple collection device for sampling of microparticles in exhaled breath.

The microparticle fraction of exhaled breath is of interest for developing clinical biomarkers. Exhaled particles may contain non-volatile components from all parts of the airway system, formed during normal breathing. This study aimed to evaluate a new, simple sampling device, based on impaction, for collecting microparticles from exhaled breath. Performance of the new device was compared with that of the existing SensAbues membrane filter device. The analytical work used liquid chromatography-tandem mass spectrometry methods. The new device collected three subsamples and these were separately analysed from eight individuals. No difference was observed between the centre position (0.91 ng/sample) and the side positions (1.01 ng/sample) using major phosphatidylcholine (PC) 16:0/16:0 as the analyte. Exhaled breath was collected from eight patients on methadone maintenance treatment. The intra-individual variability in measured methadone concentration between the three collectors was 8.7%. In another experiment using patients on methadone maintenance treatment, the sampling efficiency was compared with an established filter device. Compared to the existing device, the efficiency of the new device was 121% greater for methadone and 1450% greater for DPPC. The data from lipid analysis also indicated that a larger fraction of the collected material was from the distal parts. Finally, a study using an optical particle counter indicated that the device preferentially collects the larger particle fraction. In conclusion, this study demonstrates the usefulness of the new device for collecting non-volatile components from exhaled breath. The performance of the device was superior to the filter device in several aspects.

Complement activation in Lyme neuroborreliosis--increased levels of C1q and C3a in cerebrospinal fluid indicate complement activation in the CNS.

A strong initial inflammatory response is important in neuroborreliosis. Since complement is a main player in early inflammation, we monitored the concentration and activation of complement in plasma and cerebrospinal fluid from 298 patients, of whom 23 were diagnosed with neuroborreliosis. Using sandwich ELISAs, we found significantly elevated levels of C1q, C4, C3, and C3a in cerebrospinal fluid, but not in plasma, in patients with neuroborreliosis. This finding indicates that complement plays a role in the human immune response in neuroborreliosis, that the immunologic process is compartmentalized to the CNS, and that complement activation may occur via the classical pathway.

The use of detective quantum efficiency (DQE) in evaluating the performance of gamma camera systems.

The imaging properties of an imaging system can be described by its detective quantum efficiency (DQE). Using the modulation transfer function calculated from measured line spread functions and the normalized noise power spectrum calculated from uniformity images, DQE was calculated with the number of photons emitted from a plane source as a measure for the incoming SNR2. Measurements were made with 99mTc, using three different pulse height windows at 2 cm and 12 cm depths in water with high resolution and all purpose collimators and with two different crystal thicknesses. The results indicated that at greater depths a 15% window is the best choice. The choice of collimator depends on the details in the organ being investigated. There is a break point at 0.5 cycles cm-1 and 1.2 cycles cm-1 at 12 cm and 2 cm depths, respectively. A difference was found in DQE between the two crystal thicknesses, with a slightly better result for the thick crystal for measurements at 12 cm depth. At 2 cm depth, the thinner crystal was slightly better for frequencies over 0.5 cm-1. The determination of DQE could be a method to optimize the parameters for different nuclear medicine investigations. The DQE could also be used in comparing different gamma camera systems with different collimators to obtain a figure of merit.

Diagnosis of Lyme neuroborreliosis with antibodies to recombinant proteins DbpA, BBK32, and OspC, and VlsE IR6 peptide.

Three recombinant antigens, decorin binding protein A (DbpA), BBK32, and outer surface protein C (OspC), and IR(6) peptide of borrelial VlsE protein, were evaluated for the diagnosis of neuroborreliosis (NB), using cerebrospinal fluid (CSF) and serum samples from 89 patients. Their performances in enzyme-linked immunosorbent assay (ELISA) were compared with that of commercial flagella antigen. IgG ELISAs were performed with three variants of each recombinant antigen originating from Borrelia burgdorferi sensu stricto, B. afzelii and B. garinii, and with the IR(6) peptide. IgM antibodies were analysed against OspC and flagella. Of the patients whose CSF contained elevated anti-flagella IgG antibodies, 93% were positive for at least three of the new antigens. Of those with negative or borderline CSF anti-flagella antibodies, 51% were positive for three new antigens. Antibodies to BBK32 were detectable mainly in early disease. Antibodies to DbpA and IR(6) were observed in early and late NB. The use of the new antigens at presentation of the disease improved the laboratory diagnosis of NB. In IgG ELISAs, the diagnostic sensitivity of assays with the new antigens was between 75 and 88%, but was only 52% with the flagella antigen. The discriminatory power between patient and control samples appeared better in the CSF than in the serum. We suggest that assessment of CSF antibodies to at least two antigens, using either flagella and one of the new antigens or two of the new antigens, would improve the current diagnostic yield of NB.

Decreased Th1-type inflammatory cytokine expression in the skin is associated with persisting symptoms after treatment of erythema migrans.

BACKGROUND: Despite the good prognosis of erythema migrans (EM), some patients have persisting symptoms of various character and duration post-treatment. Several factors may affect the clinical outcome of EM, e.g. the early interaction between Borrelia (B.) burgdorferi and the host immune response, the B. burgdorferi genotype, antibiotic treatment as well as other clinical circumstances. Our study was designed to determine whether early cytokine expression in the skin and in peripheral blood in patients with EM is associated with the clinical outcome. METHODS: A prospective follow-up study of 109 patients with EM was conducted at the Åland Islands, Finland. Symptoms were evaluated at 3, 6, 12 and 24 months post-treatment. Skin biopsies from the EM and healthy skin were immunohistochemically analysed for expression of interleukin (IL)-4, IL-10, IL-12p70 and interferon (IFN)-γ, as well as for B. burgdorferi DNA. Blood samples were analysed for B. burgdorferi antibodies, allergic predisposition and levels of systemic cytokines. FINDINGS: None of the patients developed late manifestations of Lyme borreliosis. However, at the 6-month follow-up, 7 of 88 patients reported persisting symptoms of diverse character. Compared to asymptomatic patients, these 7 patients showed decreased expression of the Th1-associated cytokine IFN-γ in the EM biopsies (p=0.003). B. afzelii DNA was found in 48%, B. garinii in 15% and B. burgdorferi sensu stricto in 1% of the EM biopsies, and species distribution was the same in patients with and without post-treatment symptoms. The two groups did not differ regarding baseline patient characteristics, B. burgdorferi antibodies, allergic predisposition or systemic cytokine levels. CONCLUSION: Patients with persisting symptoms following an EM show a decreased Th1-type inflammatory response in infected skin early during the infection, which might reflect a dysregulation of the early immune response. This finding supports the importance of an early, local Th1-type response for optimal resolution of LB.

TBE in Aland Islands 1959-2005: Kumlinge disease.

Tick-borne encephalitis, TBE, has been observed in Aland Islands (population 26,500) for more than 60 years. Because of the small population, the relative incidence is high. Antibodies to TBE virus have been found in ca. 5% of healthy blood donors, indicating that subclinical infection must be common. This study is a review of the symptoms and signs of all the 301 serologically verified cases of TBE seen in Aland during 1959-2005. It also aims at analysing any possible changes in the symptoms and signs of TBE over time. The annual number of patients has been from 1 to 26, and has increased over time. The clinical picture has not undergone any conspicuous changes during these years. A few patients have had permanent neurological damage. There were no certain deaths from TBE. Simple practical measures may be taken to diminish, but not to eliminate, the risk of tick bites. Vaccination of exposed people is recommended, and general vaccination against TBE has commenced in Aland, beginning 2006. This is expected to reduce the incidence of TBE among the population to almost nil, provided that new inhabitants are vaccinated and that booster vaccinations are carried out as required.

Characteristics of erythema migrans in Borrelia afzelii and Borrelia garinii infections.

Erythema migrans is the most common manifestation of stage I Lyme borreliosis. This study investigated the relation between the subspecies of Borrelia burgdorferi involved, the time of development and the appearance of the manifestation. The study comprised 33 cases of erythema migrans yielding B. burgdorferi sensu lato by culture of skin biopsy. The species was determined by polymerase chain reaction analysis of the cultivated spirochaetes. In 22 of the cases, B. afzelii was demonstrated, whereas 11 yielded growth of B. garinii. All 11 erythemas associated with B. garinii were homogeneous, whereas 20 of the 22 associated with B. afzelii were annular. The garinii erythemas developed more rapidly, and were generally larger than the afzelii erythemas. The observations call for comparison with other geographical areas with similar, and with different, borrelial infection spectra.

Recombinant BBK32 protein in serodiagnosis of early and late Lyme borreliosis.

Borrelial protein BBK32 was evaluated as an antigen in the serodiagnosis of early and disseminated Lyme borreliosis (LB). bbk32 was cloned and sequenced from eight isolates of the three pathogenic Borrelia species. The identities between the amino acid sequences of the BBK32 proteins from Borrelia burgdorferi sensu stricto, B. garinii, and B. afzelii isolates were 71 to 100%. By immunoglobulin G (IgG) Western blotting (WB) or enzyme-linked immunosorbent assay (ELISA), up to 74 and 100% of acute- and convalescent-phase samples, respectively, from 23 patients with erythema migrans (EM) were positive for recombinant BBK32 protein from B. afzelii. In the serology of disseminated LB, the three variant BBK32 antigens cross-reacted. In total, 14 of 14 samples from patients with neuroborreliosis and 15 of 15 samples from patients with Lyme arthritis were positive. The specificities of the IgG ELISA with the variant BBK32 antigens for EM and disseminated borreliosis were 81 to 92% and 89 to 95%, respectively. Our findings indicate that the BBK32 proteins are promising serodiagnostic antigens for the detection of early and disseminated LB but that variant BBK32 proteins may be needed either in parallel or in combination with an immunoassay for LB to cover all the relevant borrelial species that cause the disease.