Determinants of site of tuberculosis disease: An analysis of European surveillance data from 2003 to 2014

Abstract

Background: We explored host-related factors associated with the site of tuberculosis (TB) disease using variables routinely collected by the 31 EU/EEA countries for national surveillance.

Methods: Logistic regression models were fitted to case-based surveillance data reported to the European Centre for Disease Prevention and Control for TB cases notified from 2003 to 2014. Missing data on HIV infection and on susceptibility to isoniazid and rifampicin for many patients precluded the inclusion of these variables in the analysis. Records from Finland, Lithuania, Spain and the United Kingdom were excluded for lack of exact details of disease localisation; other records without one or more variable (e.g. previous treatment history, geographical origin) or who had mixed pulmonary and extrapulmonary disease or more than one form of extrapulmonary disease were also removed (total exclusion = 38% of 913,637 notifications).

Results: 564,916 TB cases reported by 27 EU/EEA countries had exclusive pulmonary (PTB; 83%) or extrapulmonary (EPTB; 17%) disease. EPTB was associated with age <15 years (aOR: 5.50), female sex (aOR: 1.60), no previous TB treatment (aOR: 3.10), and geographic origin (aOR range: 0.52-3.74). Origin from the Indian subcontinent or Africa was most strongly associated with lymphatic, osteo-articular and peritoneal/digestive localization (aOR>3.7), and age <15 years with lymphatic (aOR: 17.96) and central nervous system disease (aOR: 11.41).

Conclusions: Awareness of host-related determinants of site of TB is useful for diagnosis. The predilection for EPTB among patients originating from countries outside Europe may reflect strain preferences for disease localization, geographic/ethnic differences in disease manifestation and other factors, like HIV.

Fig 1. Selection of records for the analysis of determinants of site of TB, EU/EEA countries, 2003–2014.

Fig 2. Regional grouping of countries of origin used in the analysis of determinants of site of TB, EU/EEA countries, 2003–2014.

The boundaries and names shown and the designations used on this map do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines on maps represent approximate border lines for which there may not yet be full agreement.

Fig 3. Distribution of TB cases in the 27 countries included in the multivariable analysis of determinants of site of TB, EU/EEA countries, 2003–2014.

SOURCE OF GRAPHIC: ECDC Map Maker (EMMa), available at https://emma.ecdc.europa.eu The boundaries and names shown and the designations used on this map do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines on maps represent approximate border lines for which there may not yet be full agreement.