Tuberculosis incidence among migrants according to migrant status: a cohort study, Denmark, 1993 to 2015.

BackgroundMigrants account for the majority of tuberculosis (TB) cases in low-incidence countries in western Europe. TB incidence among migrants might be influenced by patterns of migration, but this is not well understood.AimTo investigate differences in TB risk across migrant groups according to migrant status and region of origin.MethodsThis prospective cohort study included migrants ≥ 18 years of age who obtained residency in Denmark between 1 January 1993 and 31 December 2015, matched 1:6 to Danish-born individuals. Migrants were grouped according to legal status of residency and region of origin. Incidence rates (IR) and incidence rate ratios (IRR) were estimated by Poisson regression.ResultsThe cohort included 142,314 migrants. Migrants had significantly higher TB incidence (IR: 120/100,000 person-years (PY); 95% confidence interval (CI): 115-126) than Danish-born individuals (IR: 4/100,000 PY; 95% CI: 3-4). The IRR was significantly higher in all migrant groups compared with Danish-born (p < 0.01). A particularly higher risk was seen among family-reunified to refugees (IRR: 61.8; 95% CI: 52.7-72.4), quota refugees (IRR: 46.0; 95% CI: 36.6-57.6) and former asylum seekers (IRR: 45.3; 95% CI: 40.2-51.1), whereas lower risk was seen among family-reunified to Danish/Nordic citizens (IRR 15.8; 95% CI: 13.6-18.4) and family-reunified to immigrants (IRR: 16.9; 95% CI: 13.5-21.3).DiscussionAll migrants had higher TB risk compared with the Danish-born population. While screening programmes focus mostly on asylum seekers, other migrant groups with high risk of TB are missed. Awareness of TB risk in all high-risk groups should be strengthened and screening programmes should be optimised.

Prognostic value of interferon-γ release assays, a population-based study from a TB low-incidence country.

BACKGROUND: The ability of interferon-γ release assays to predict the development of TB has been investigated in many studies, but few cases develop TB during follow-up limiting the generalisation of results. METHODS: We assessed QuantiFERON-TB Gold In-Tube test (QFT) results from 15 980 Danish individuals and data on all TB cases in Denmark from 2005 to 2012 and determined the predictive value of the QFT for coprevalent TB (0-90 days after testing) and incident TB (>90 days). RESULTS: Coprevalent TB was diagnosed in 10.7% (183/1703) and 0.3% (38/13 463) cases with a positive and negative QFT, respectively. For the QFT-positive cases, coprevalent TB was more frequent among persons <35 years compared with those >35  years (19.3% vs 7.2%, p<0.001). The cohort was followed-up for 52 807 person-years, median follow-up time was 3.36 years. For incident TB, the positive and negative predictive values (PPV and NPV) were 1.32% and 99.85%, respectively. Incidence rates (IR) for incident TB among QFT-positives and QFT-negatives were 383 per 10(5) and 45 per 10(5) person-years, respectively. Among cases with a positive QFT, IR for incident TB was associated with time interval since QFT (<2 years, p<0.001), but not with age (<35 years, p=0.087). CONCLUSIONS: We confirmed a high NPV of the QFT and found positive QFT associated with a higher risk of subsequent incident TB. Overall, the PPV for incident cases was 1.32%, and development of incident TB was associated with time interval after the QFT, but not with age.

Tuberculosis screening among newly arrived asylum seekers in Denmark.

BACKGROUND: Tuberculosis (TB) screening programmes among asylum seekers tend to focus on chest radiography (CXR) for early diagnosis, whereas knowledge on sputum examination is limited. We evaluated active TB screening using CXR and sputum culture among asylum seekers arriving in Denmark. In addition, we assessed the coverage of a voluntary health assessment. METHODS: Between 1 February 2017 and 31 March 2019, all newly arrived asylum seekers in Denmark ≥ 18 years from TB high-incidence countries or risk groups, who attended a voluntary general health assessment, were offered active TB screening with CXR and spot sputum examination. Sputum samples were examined by culture and smear microscopy. RESULTS: Coverage of the general health assessment was 65.1%. Among 1,154 referred for active TB screening, 923 (80.0%) attended. Of these, 854 were screened by CXR and one case of active TB was identified equivalent to a yield of 0.12%. Sputum samples were collected from 758 and one M. tuberculosis culture-positive TB case (also identified by CXR) was identified, equivalent to a yield of 0.13%. No cases were found by sputum culture screening only. In addition, screening found three cases of malignant disease. CONCLUSION: We suggest that TB screening should focus on asylum seekers from TB high-incidence countries. Furthermore, early health assessments should be of high priority to ensure migrant health.

Cerebrospinal fluid pleocytosis in infectious and noninfectious central nervous system disease: A retrospective cohort study.

Cerebrospinal fluid (CSF) analysis is the most important tool for assessing central nervous system (CNS) disease. An elevated CSF leukocyte count rarely provides the final diagnosis, but is almost always an indicator of inflammation within the CNS.The present study investigated the variety of diseases associated with CSF pleocytosis.CSF analyses were identified through the biochemical database used in the capital region of Denmark in the period from 2003 to 2010. In patients >15 years, clinical diagnoses associated with the finding of a CSF leukocyte count >10 × 10 cells/L were obtained from discharge records and patient files.A total of 1058 CSF samples from 1054 patients were included in the analysis. The median age was 50 (interquartile range: 36-67) and 53% were male. Eighty-one different diagnoses were identified in 1058 cases with an elevated CSF leukocyte count, besides unknown causes. Infections were the most common cause of CSF pleocytosis (61.4%) followed by miscellaneous causes (12.7%), vascular (9.7%), neurodegenerative (7%), neoplastic (5%), and inflammatory conditions (4.2%). Only infections presented with leukocyte counts >10,000 × 10/L. Infections represented 82.6% of all cases with a leukocyte count >100 × 10/L whereas 56.3% of cases with at leukocyte counts <100 × 10/L were dominated by disease not related to infection.The present study may serve as a reminder to clinicians of what diseases and disease categories to suspect when patients present with CSF biochemistry indicating CNS inflammation.