While bacteriology can be used to confirm a TB diagnosis for the majority of patients, such confirmation is not always possible in a significant proportion of cases, and the percentage is rising with the increase in TB/HIV coinfection. Furthermore, although the current diagnostic algorithm calls for the use of chest radiography as part of diagnosis, the procedure has, in the past, been neither standardised nor reliable.

The Union has been involved in a multi-pronged effort to improve this situation:

• Through a large international collaborative trial, The Union demonstrated the reliability of a standard reading and recording system in the surveillance of tuberculosis. This project built on the pioneering work of the late Prof Neil White from Cape Town and was also funded by USAID.
• The Union's experts have outlined the methods needed to arrive at excellent concordance in reading chest radiographs that can be used in any setting
• A guide to CXR was developed through a collaboration led by the Japan Anti-tuberculosis Association and funded by USAID. It was published by TBCTA in 2008. (See Publications)
•  An international course in chest x-ray reading and recording is now offered by The Union and the Desmond Tutu TB Centre by the University of Cape Town (See Other Technical Courses).
• This group is working in collaboration with the Delft Corporation, a large international firm providing x-ray equipment, to evaluate and promote the use of digital technology for this examination.
• In addition, national courses on reading chest X-rays have been organised in Benin, Burkina Faso, DR Congo, Côte d'Ivoire and Togo, with the technical support of Soutien Pneumologique International and the financial support of the Agence Française de Développement (AFD).

The Union continues to work towards improving the quality of chest radiograph readings in a variety of settings and to extend this standardisation to digital technology. In March 2010, TREAT TB convened a Global Consultation on Digital Radiography for TB Control in Low-Resource/High-Burden Settings in Paris.

With these improvements, the quality of diagnosis for that significant (and increasing) proportion of patients who are not bacteriologically confirmed will be enhanced and general diagnostic facilities will be improved in low-income countries.