Evaluation of the Abbott ARCHITECT™ cytomegalovirus IgM/IgG, rubella IgM/IgG, and syphilis treponemal antibodies enzyme immunoassays in a mother and child health center population.

This study evaluated the concordance of Architect™ chemiluminescent microparticle immunoassays with Captia™ ELISA for cytomegalovirus (CMV) IgM and IgG, with Enzygnost™ and Captia™ ELISA for rubella IgM and IgG and with Trep-Sure™ ELISA for syphilis treponemal antibodies in a mixed pediatric and obstetrical population. Total agreement between assays and Kappa statistic value were 82.5% (95% CI: 75.6-87.7) and 0.65 (95% CI: 0.54-0.77) for CMV IgM, 82.8% (95% CI: 76.7-87.6) and 0.65 (95% CI: 0.55-0.75) for CMV IgG, 89.2% (95% CI: 82.9-93.4) and 0.56 (95% CI: 0.36-0.75) for rubella IgM, 88.6% (95% CI: 82.9-92.6) and 0.74 (95% CI: 0.63-0.84) for rubella IgG, and 97.9% (95% CI: 94.5-99.4) and 0.89 (95% CI: 0.79-1.00) for syphilis treponemal antibodies. This study demonstrates that the Architect™ chemiluminescent microparticle immunoassays correlate well with other FDA-approved ELISA assays in this specific population.

Evaluation of the abbot Architect(™) epstein-barr virus viral capsid antigen IgM, viral capsid antigen IgG and nuclear antigen IgG assays in a pediatric and adult population.

BACKGROUND: The detection of antibodies against Epstein-Barr viral capsid (VCA) and nuclear (EBNA) antigens is routinely performed with different commercially available immunoassays. OBJECTIVES: In this study, we evaluated the concordance and performance of the Architect(™) chemiluminescent microparticle immunoassays (CMIAs) using Captia(™) enzyme linked immunosorbent assays (ELISA) for VCA IgM, and standard immunofluorescence (IF) assays for VCA IgG and EBNA IgG as comparative techniques. STUDY DESIGN: Sera were selected from a heterogeneous population including pediatric and adult patients. RESULTS: Concordance between CMIAs and comparative assays was high with total agreement percentages of 84,1% (95% CI: 77.8-88.9) for VCA IgM, 90,6% (95% CI: 84.2-94.7) for EBNA IgG and 98,0% (95% CI: 93.9-99.6) for VCA IgG. Moreover, kappa statistic values showed good to excellent correlation with values of 0.68 (95% CI: 0.57-0.79) for VCA IgM, 0.73 (95% CI: 0.58-0.87) for EBNA IgG and 0.95 (95% CI: 0.89-1.00) for VCA IgG. A correlation was observed between positivity levels on CMIAs and semi-quantitative fluorescence intensity on IF for VCA IgG and EBNA IgG assays. With regard to an accepted gold standard IF assays, CMIA was 98,1% (95% CI: 93.3-99.8) sensitive and 97,4% (95% CI: 86.5-99.9) specific for the detection of VCA IgG. For the detection of EBNA IgG, it was 92,2% (95% CI: 85.1-96.6) sensitive and 84,6% (95% CI: 65.1-95.6) specific. CONCLUSION: In summary, we demonstrated that the CMIA EBV antibody detection panel has high performance and high concordance with other commercially available immunoassays.

Evaluation of a fluorescent immunoassay rapid test (Sofia™) for detection of influenza A+B and RSV in a tertiary pediatric setting.

In response to the lack of sensitivity and reproducibility of previously marketed rapid antigen detection tests, a novel fluorescent immunoassay was recently developed. This new assay offers rapidity and automated reading. More characterization of this assay is needed. The aim of this study was to assess diagnostic performance of Sofia influenza A+B and respiratory syncytial virus (RSV) while compared to traditional viral cell culture. A total of 416 respiratory samples were analyzed prospectively with both methods in a tertiary pediatric center. Sensitivity and specificity of the Sofia™ test were 90.0% and 98.0% for influenza A, 90.9% and 98.9% for influenza B, and 87.7% and 94.7% for RSV compared to traditional cell culture. Overall, Sofia influenza A+B and RSV assays performed well in comparison to culture in a pediatric population.

Predictive value of nonspecific bronchial responsiveness in occupational asthma.

BACKGROUND: The diagnosis of occupational asthma (OA) can be challenging and needs a stepwise approach. However, the predictive value of the methacholine challenge has never been addressed specifically in this context. OBJECTIVE: We sought to evaluate the sensitivity, specificity, and positive and negative predictive values of the methacholine challenge in OA. METHODS: A Canadian database was used to review 1012 cases of workers referred for a suspicion of OA between 1983 and 2011 and having had a specific inhalation challenge. We calculated the sensitivity, specificity, and positive and negative predictive values of methacholine challenges at baseline of the specific inhalation challenge, at the workplace, and outside work. RESULTS: At baseline, the methacholine challenge showed an overall sensitivity of 80.2% and a specificity of 47.1%, with positive and negative predictive values of 36.5% and 86.3%, respectively. Among the 430 subjects who were still working, the baseline measures displayed a sensitivity of 95.4%, a specificity of 40.1%, and positive and negative predictive values of 41.1% and 95.2%, respectively. Among the 582 subjects tested outside work, the baseline measures demonstrated a sensitivity and specificity of 66.7% and 52%, respectively, and positive and negative predictive values of 31.9% and 82.2%, respectively. When considering all subjects tested by a methacholine challenge at least once while at work (479), the sensitivity, specificity, and positive and negative predictive values were 98.1%, 39.1%, and 44.0% and 97.7%, respectively. CONCLUSION: A negative methacholine challenge in a patient still exposed to the causative agent at work makes the diagnosis of OA very unlikely.

Grief reactions and impact of patient death on pediatric oncologists.

BACKGROUND: To examine pediatric oncologists' grief reactions to patient death, and the impact patient death has on their personal and professional lives. PROCEDURE: The grounded theory method was used. Data was collected between March 2012 and July 2012 at two academic centres in Canada. Twenty-one out of 34 eligible pediatric oncologists at different stages of their career were recruited and interviewed about their experiences with patient death. Inclusion criteria were: being able to speak English and having had a patient die in their care. The participants formed three groups of oncologists at different stages of career including: fellows, junior oncologists, and senior oncologists who varied in sub-specialties, gender, and ethnicities. RESULTS: Pediatric oncologists reported a range of reactions to patient death including sadness, crying, sleep loss, exhaustion, feeling physically ill, and a sense of personal loss. They also reported self-questioning, guilt, feelings of failure and helplessness. The impact of these deaths had personal consequences that ranged from irritability at home, feeling disconnected from family members and friends, and becoming more desensitized towards death, to gaining a greater and more appreciative perspective on life. Professional impacts included concern about turnover or burnout at work and improving holistic care as a result of patient deaths. CONCLUSIONS: Grief over patient death and the emotional labour involved in these losses are a robust part of the pediatric oncology workplace and have major impacts on pediatric oncologist's personal and professional lives. Interventions that focus on how to help pediatric oncologists deal with these reactions are needed.

Efficacy of brief motivational interviewing to improve adherence to inhaled corticosteroids among adult asthmatics: results from a randomized controlled pilot feasibility trial.

PURPOSE: Daily adherence to inhaled corticosteroid (ICS) regimens is one of the most important factors linked to achieving optimal asthma control. Motivational interviewing (MI) is a client-centered communication style that focuses on enhancing intrinsic motivation to engage in appropriate self-management behaviors. MI has been shown to improve a variety of health behaviors including medication adherence in other disorders, but its efficacy for the improvement of ICS adherence in asthmatics has yet to be examined. This pilot "proof of concept" trial assessed the feasibility of MI to improve daily ICS adherence and asthma control levels in adult asthmatics. METHODS: Fifty-four poorly controlled (Asthma Control Questionnaire [ACQ] score ≥1.5), highly nonadherent (filled <50% of ICS medication in the last year) adult asthmatics were recruited from the outpatient asthma clinic of a university-affiliated hospital. Participants underwent baseline assessments and were randomly assigned to MI (3×30 minutes sessions within a 6-week period, n=26) or a usual care (UC) control group (n=28). ICS adherence (% pharmacy refills) and asthma control (ACQ, Asthma Control Test [ACT]) were measured at 6 and 12 months postintervention. Mixed model repeated measure analyses for both intent-to-treat and per-protocol were used. Results were adjusted for a priori-defined covariates including baseline adherence. Patients in the MI group also reported their impressions of the intervention. RESULTS: Six-month adjusted intent-to-treat analyses revealed a mean change in the percentage of ICS refills of 13% in the MI group vs 6% in the UC group (between group net improvement associated with MI =+6% [-12% to 24%]). Twelve-month analyses revealed a mean change in the percentage of ICS refills of 11% (MI group) vs 7% in the UC group (between group net improvement associated with MI =+3% [-11% to 18%]) representing an effect size (ES) of d=0.20 (medium). Six-month adjusted net improvement in ACQ and ACT scores between MI and control groups was -0.2 and +0.7, respectively, with improvements being even more pronounced at 12 months (ACQ =-0.5; ACT =+1.1; ES, d=0.12 and 0.18 [small], respectively). Interestingly, 6- and 12-month net improvements in asthma self-efficacy (which is specifically targeted by MI) improved by +0.4 and +0.4, respectively, with an ES of d=0.46 (marginally large). Patients in the MI group rated the intervention overwhelmingly positively in terms of usefulness, pertinence, feasibility, enjoyableness, and likelihood to change adherence behavior. CONCLUSION: Results suggest that a brief (90 minutes) MI intervention that targets ICS adherence can produce clinically significant improvements in adherence behavior, asthma control levels, and asthma self-efficacy in poorly controlled nonadherent asthmatics at 6 months that are maintained for 1 year, and it is well accepted by patients. Future studies including larger sample sizes, modified intervention designs (eg, MI "booster" sessions), and assessments of the extent behavior changes translate into clinical improvements (eg, in asthma control and quality of life) are warranted.

Prospective impact of panic disorder and panic-anxiety on asthma control, health service use, and quality of life in adult patients with asthma over a 4-year follow-up.

Background Panic disorder (PD) is a common anxiety disorder among asthmatic patients with overlapping symptoms (e.g., hyperventilation). However, the longitudinal impact of PD on asthma control remains poorly understood. This study assessed the impact of PD and panic-anxiety on asthma control over a 4.3-year follow-up in 643 adult asthmatic patients. Methods Consecutive patients presenting to a tertiary asthma clinic underwent a sociodemographic, medical history, and psychiatric (Primary Care Evaluation of Mental Disorders) interview and completed questionnaires including the Anxiety Sensitivity Index (ASI) to assess panic-anxiety. At follow-up, patients completed the Asthma Control (ACQ) and Asthma Quality of Life (AQLQ) questionnaires and reported emergency department visits and hospitalizations during the follow-up. Results Baseline frequency of PD was 10% (n = 65). In fully adjusted models, analyses revealed that PD and ASI scores predicted worse follow-up ACQ total scores (ß = 0.292, p = .037; ß = 0.012, p = .003) but not AQLQ total scores. ASI scores also predicted greater nocturnal and waking symptoms, activity limitations, and bronchodilator use on the ACQ (ß = 0.012-0.018, p < .05) as well as lower symptom (ß = -0.012, p = .006) and emotional distress (ß = -0.014, p = .002) subscale scores on the AQLQ. Neither PD nor ASI scores were associated with hospitalizations, although ASI scores (but not PD) were associated with an increased risk of emergency department visits (relative risk = 1.023, 95% confidence interval = 1.001-1.044). Conclusions PD and anxiety sensitivity are prospectively associated with poorer asthma control and may be important targets for treatment.

Long-term socioprofessional and psychological status in workers investigated for occupational asthma in quebec.

OBJECTIVE: To compare the long-term status of workers with occupational asthma (OA) with those of subjects with work-exacerbated asthma (WEA) and nonasthmatic (NA) workers. METHODS: We contacted 179 subjects investigated for suspected OA at Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada, from 1997 to 2007. Participants completed questionnaires on psychological and functional status, followed by a telephone interview about socioprofessional outcomes and health care utilization. RESULTS: The OA workers are more likely to have been removed from the workplace than the WEA workers. The health-related quality of life of all workers was still impaired. A high prevalence of psychiatric disorders was found among OA and WEA workers. Compared with WEA and OA workers, the NA group showed a higher rate of physician consultations for all causes. CONCLUSIONS: Regardless of the diagnosis they received, these workers need to benefit from psychosocial support in the period after investigation for suspicion of OA.

The effects of a multisite aerobic exercise intervention on asthma morbidity in sedentary adults with asthma: the Ex-asthma study randomised controlled trial protocol.

OBJECTIVE: Aerobic exercise can improve cardiovascular fitness and does not seem to be detrimental to patients with asthma, though its role in changing asthma control and inflammatory profiles is unclear. The main hypothesis of the current randomised controlled trial is that aerobic exercise will be superior to usual care in improving asthma control. Key secondary outcomes are asthma quality of life and inflammatory profiles. DESIGN: A total of 104 sedentary adults with physician-diagnosed asthma will be recruited. Eligible participants will undergo a series of baseline assessments including: the asthma control questionnaire; the asthma quality-of-life questionnaire and the inflammatory profile (assessed from both the blood and sputum samples). On completion of the assessments, participants will be randomised (1:1 allocation) to either 12-weeks of usual care or usual care plus aerobic exercise. Aerobic exercise will consist of three supervised training sessions per week. Each session will consist of taking a short-acting bronchodilator, 10 min of warm-up, 40 min of aerobic exercise (50-75% of heart rate reserve for weeks 1-4, then 70-85% for weeks 5-12) and a 10 min cool-down. Within 1 week of completion, participants will be reassessed (same battery as at baseline). Analyses will assess the difference between the two intervention arms on postintervention levels of asthma control, quality of life and inflammation, adjusting for age, baseline inhaled corticosteroid prescription, body weight change and pretreatment dependent variable level. Missing data will be handled using standard multiple imputation techniques. ETHICS AND DISSEMINATION: The study has been approved by all relevant research ethics boards. Written consent will be obtained from all participants who will be able to withdraw at any time. RESULTS: The result will be disseminated to three groups of stakeholder groups: (1) the scientific and professional community; (2) the research participants and (3) the general public. REGISTRATION DETAILS CLINICALTRIALSGOV IDENTIFIER: NCT00953342.

Screening for occupational asthma by using a self-administered questionnaire in a clinical setting.

OBJECTIVE: Because of its high prevalence, early screening for occupational asthma (OA) is crucial. We aimed to evaluate the screening performance of the Occupational Asthma Screening Questionnaire-11 items (OASQ-11) in a clinical setting. METHODS: Between January 2009 and December 2011, 169 workers referred for potential OA to our hospital completed the OASQ-11 and underwent workups to determine the final diagnosis. The discriminative abilities of the OASQ-11 as a whole and in relation to demographic and exposure parameters were determined by the area under the receiving operator characteristic curve (AUC). RESULTS: Model 1, consisting of the OASQ's items, showed fair discrimination (AUC, 0.69; 95% confidence interval, 0.58 to 0.80). Addition of age and exposure duration to model 1 improved discrimination (AUC, 0.80; confidence interval, 0.72 to 0.88). CONCLUSION: A simple model consisting of the OASQ-11's items, age, and exposure duration could well discriminate subjects with OA in a clinical setting.

Prevalence of psychiatric disorders among patients investigated for occupational asthma: an overlooked differential diagnosis?

RATIONALE: Up to one-third of patients assessed for occupational asthma (OA) do not receive a diagnosis of OA or any other medical disorder. Although several differential diagnoses are considered (e.g., rhinitis, chronic obstructive pulmonary disease), psychiatric disorders (many with somatic complaints that mimic asthma) are rarely considered or assessed. OBJECTIVES: To assess the prevalence of psychiatric disorders (mood and anxiety disorders and hypochondriasis) in patients suspected of having OA, and whether psychiatric morbidity increases the risk of not receiving any medical diagnosis. METHODS: A total of 219 consecutive patients (57% male; mean age, 41.8 ± 11.1 yr) underwent sociodemographic and medical history interviews on the control or specific inhalation testing day of their OA evaluation. The Primary Care Evaluation of Mental Disorders was used to assess mood and anxiety disorders, and the Whiteley Hypochondriasis Index was used to assess hypochondriasis. MEASUREMENTS AND MAIN RESULTS: A total of 26% (n = 50) of patients had OA; 25% (n = 48) had asthma or work-exacerbated asthma; 14% (n = 28) had another inflammatory disorder; 13% (n = 26) had a noninflammatory disorder; and 22% (n = 44) did not receive any medical diagnosis. A total of 34% (n = 67) of patients had a psychiatric disorder: mood and anxiety disorders affected 29% (n = 57) and 24% (n = 46) of the sample, respectively, and 7% (n = 12) had scores on the Whiteley Hypochondriasis Index indicating hypochondriasis. Hypochondriasis, but not mood or anxiety disorders, was associated with an increased risk of not receiving any medical diagnosis (adjusted odds ratio, 3.92; 95% confidence interval, 1.18-13.05; P = 0.026). CONCLUSIONS: Psychiatric morbidity is common in this population, and hypochondriasis may account for a significant proportion of the "undiagnosable" cases of patients who present for evaluation of OA.

Integrated approach to diagnosis of associated occupational asthma and rhinitis.

Patients with coexisting work-related rhinitis and asthma would benefit from an adequate and simultaneous recognition of both diseases. The present case illustrates the advantages and importance of using an integrated approach to confirm a diagnosis of occupational rhinitis (OR) and occupational asthma (OA). A 38-year-old woman, who worked as an animal laboratory technician since 2004, first noticed the appearance of rhinitis and conjunctivitis symptoms in 2007 when she was exposed to rats. A skin-prick test with rat extract was strongly positive. A specific inhalation challenge with parallel assessment of nasal and bronchial responses was conducted. After 10 min of exposure, she developed rhinitis and conjunctivitis symptoms, her forced expiratory volume in 1 s dropped by 27.5% and her nasal volume, measured by acoustic rhinometry, decreased by 80% from baseline values. After allergen exposure, induced sputum and nasal lavage examination demonstrated an increase in eosinophils (11% and 20%, respectively). A diagnosis of associated allergic OA and OR was confirmed and she was advised to stop working with rats. A systematic and parallel diagnostic approach enables confirmation of a diagnosis of OA and OR in patients complaining of work-related rhinitis and asthma symptoms.

Occupational asthma: new deleterious agents at the workplace.

This article summarizes the main new categories of occupational agents responsible for causing occupational asthma, with and without a latency period reported in the last 10 years. It also reports examples of occupational agents for which the fabrication processing or use have influenced the outcome of occupational asthma.

Association between asthma medications and suicidal ideation in adult asthmatics.

BACKGROUND: Asthma has been associated with suicidal ideation (SI), though the mechanisms remain poorly understood. Some asthma medications (e.g., theophylline and beta-2 adrenergic agonists) have been shown to provoke feelings of anxiety, fear, and irritability, but their link to SI among asthmatics has not been examined, which was the purpose of the present study. METHODS: 664 adult asthma outpatient (39% male, M age = 49 ± 14.3) underwent a sociodemographic, psychiatric, and medical history interview. Patients reported asthma medication use, which was verified by chart review. All patients underwent spirometry and completed questionnaires including the beck depression inventory-II (BDI-II) which includes an item that assesses SI in the past two weeks. RESULTS: 11.5% of patients reported having SI in the past two weeks. After adjusting for age, sex, smoking, asthma severity, and depressive disorders, analyses indicated that theophylline use was associated with an increased likelihood of SI (OR = 2.67, 95% CI = 1.07-6.65). Sensitivity analyses including asthma control levels and benzodiazepine use as additional covariates did not alter this association (respectively: OR = 2.54, 95% CI = 1.04-6.37; OR = 2.71, 95% CI = 1.09-6.78), though adding cohabitation rendered it no longer statistically significant (OR = 2.34, 95% CI = 0.90-6.09). There were no associations between SI and LABA use. CONCLUSIONS: Findings suggest that theophylline but not LABA use may be associated with an increased risk of SI among adult asthmatics independent of depressive disorders, asthma control levels, and asthma severity, but not cohabitation, suggesting that cohabitation may be important for SI in this population. Physicians should be cautious when prescribing theophylline or similar agents to asthmatics, and ensure adequate follow-up.

Effect of an integrated care programme on re-hospitalization of patients with chronic obstructive pulmonary disease.

BACKGROUND AND OBJECTIVE: Hospital admissions due to exacerbations of chronic obstructive pulmonary disease (COPD) have a major impact on disease progression and costs. We hypothesized that a 1-year integrated care (IC) programme comprising two components (patient-centred education+case management) would be effective in preventing COPD-related hospitalizations. METHODS: This was a retrospective longitudinal cohort study. Data were retrieved both from an administrative database in the province of Quebec (Canada), and from the medical records at two hospitals in Montreal. One hundred and eighty-nine COPD patients were randomly selected from registers at these centres, from 2004 to 2006. Patients in the intervention group underwent a programme comprising two components: patient -centred education-involving three group sessions of self-management education that included one motivational interview and instruction in the use of a written action plan; and case management-involving scheduled follow-up visits with access to a call centre. The intervention group was compared with a group receiving usual care (UC). The main outcome was COPD-related re-hospitalizations, with length of hospital stay and emergency department (ED) visits being secondary outcomes. RESULTS: Logistic regression analysis with adjustment for covariates showed that there was a lower probability of re-hospitalization over the follow-up year in the IC group compared with the UC group (odds ratio 0.44; 95% confidence interval 0.23-0.85). Subgroup analyses revealed that the IC programme prevented more COPD-related hospitalizations in women compared with men. There were no significant between-group differences in length of hospital stay or number of ED visits. CONCLUSIONS: An IC programme combining self-management education and case-management can decrease rates of COPD-related hospitalizations, particularly among women.

Irritant-induced asthma.

PURPOSE OF REVIEW: To describe the recent insights into the definition, causes, natural outcome, and key elements of irritant-induced asthma (IIA) management. RECENT FINDINGS: IIA is a subtype of occupational asthma without immunologic sensitization and includes the typical reactive airway dysfunction syndrome (RADS) and a more gradual form called not-so-sudden IIA, when onset of asthma follows repeated low-dose exposure to irritants. The World Trade Center tragedy brought new insight in the understanding of IIA, suggesting that it can exhibit a prolonged interval between exposure and recognition of clinical symptoms and disease. Dimethyl sulfate has been recently reported to cause RADS and repeated diesel exhaust exposure to cause not-so-sudden IIA in patients who worked in a bus garage. Cleaning workers who are exposed to a large variety of irritants and sensitizers are especially at risk of occupational asthma and IIA. SUMMARY: IIA includes RADS and not-so-sudden IIA. Outcome of IIA is as poor as occupational asthma with sensitization. Treatment of IIA does not differ from standard asthma treatment, but high-dose vitamin D could be assessed further for possible therapeutic benefit.

Does a self-management education program have the same impact on emotional and functional dimensions of HRQoL?

Most previous research evaluating the effect of interventions on HRQoL in COPD patients has focused on measuring HRQoL using aggregated questionnaire scores, increasing the risk of false-negative results. There is also evidence to suggest that self-evaluations of functional status are less likely to be modified over time relative to self-evaluation of emotional status. This study was a secondary analysis of a prospective study that compared the efficacy of a self-management education program (SM) on emotional and functional dimensions of HRQoL. One hundred and ten patients were recruited from the Sacré-Coeur Hospital of Montreal (Canada). Patients were included in either the SM group (n = 60) or the usual-care group (UC, n = 50). The SM group underwent a 4-week intervention based on content featured in "Living Well with COPD" program. Patients were assessed pre and 12-months post-intervention; the primary outcome was net change in the emotional and functional subscales scores of the St-George's Respiratory Questionnaire (SGRQ) and Short-Form health survey questionnaire (SF-36). Only the emotional dimension scores of both the SGRQ (impact) and the SF-36 (mental component summary) were statistically and clinically improved in the SM group compared to UC. Also, the 12-month adjusted between-group difference in the SGRQ-impact scores was 3-fold higher than the minimum clinically important difference in SM vs. UC patients. HRQoL needs to be regarded as a combination of distinct self-evaluations with unique dynamics over time. This distinction should be taken into account in program development and evaluation, to choose intervention components likely to impact on both types of self-evaluations related to HRQoL.

Application and interpretation of an interferon-gamma release assay: Results of an audit in a Canadian centre.

BACKGROUND: Interferon-gamma release assays (IGRAs) are newly approved for diagnosing latent tuberculosis infection (LTBI). An internal audit was conducted to review the use of a newly implemented IGRA at the Hôpital du Sacré-Coeur de Montréal (Montréal, Québec) to evaluate its concordance with Canadian recommendations and its implication on diagnosis. METHODS: From April 2007 to January 2009, all Quantiferon TB Gold In-Tube (QFT, Cellestis inc, USA) tests performed in at the Hôpital du Sacré-Coeur de Montréal were retrieved. Strategies used to investigate LTBI and clinical interpretation of test results were compared with the local algorithm, which is derived from the current national guidelines. RESULTS: A total of 200 patients tested with QFT were included in the analysis. LTBI investigation and QFT testing were considered to be appropriate in 87.5% and 66.5% of patients, respectively. Overall, 67 QFT tests were performed inappropriately; 25 were performed when a LTBI investigation was not indicated and 42 were performed whe LTBI interpretation was possible with the result of the tuberculin skin test alone. Among the 175 patients investigated appropriately for LTBI, 49 QFT tests (28%) were interpreted incorrectly; 32 patients (at high risk of developing active tuberculosis) had a positive tuberculin skin test and a negative QFT result wrongly interpreted as being negative for LTBI and 13 patients should have undergone further LTBI investigations. CONCLUSION: Globally, the present study revealed that there are discrepancies on how the IGRA was employed and interpreted in a Montreal hospital and that strict compliance to the guidelines could significantly reduce errors in interpretation.

HISTORIQUE: Les tests de libération d'interféron gamma (TLIG) ont récemment été approuvés pour diagnostiquer une infection tuberculeuse latente (ITBL). Une vérification interne a été organisée pour examiner l'utilisation d'un nouveau TLIG à l'Hôpital du Sacré-Cœur de Montréal (Montréal, Québec) ainsi que pour en évaluer la concordance avec les recommandations canadiennes et les conséquences sur le diagnostic. MÉTHODOLOGIE: D'avril 2007 à janvier 2009, les chercheurs ont extrait tous les tests Quantiferon TB Gold In-Tube (QFT) effectués à leur centre. Ils ont comparé les stratégies utilisées pour évaluer l'ITBL et l'interprétation clinique des résultats des tests avec leur algorithme local, dérivé des lignes directrices nationales à jour. RÉSULTATS: Au total, 200 patients ayant subi le test QFT ont participé à l'analyse. L'examen de l'ITBL et le test QFT ont été considérés comme convenables chez 87,5 % et 66,5 % des patients, respectivement. Dans l'ensemble, 67 tests QFT avaient été mal exécutés, soit 25 lorsque l'examen de l'ITBL n'était pas indiqué et 42 lorsqu'il était possible d'interpréter l'ITBL grâce aux seuls résultats du test cutané à la tuberculine. Chez les 175 patients ayant subi des examens convenables de l'ITBL, 49 tests QFT (28 %) avaient été mal interprétés. En effet, 32 patients (très vulnérables à une tuberculose active) présentaient un test cutané à la tuberculine positif et un résultat négatif du test QFT interprété à tort comme négatif à l'ITBL, tandis que 13 patients auraient dû subir des examens plus approfondis de l'ITBL. CONCLUSION: Globalement, la présente étude a révélé des divergences dans l'utilisation du TLIG au centre et établi qu'un respect rigoureux des lignes directrices pourrait réduire considérablement les erreurs d'interprétation.