Pediatr Radiol (2014) 44:687–689 DOI 10.1007/s00247-014-2918-z
MINISYMPOSIUM
Partnering to solve the problem of tuberculosis Bernard F. Laya & Amanda Dehaye
Received: 16 November 2013 / Accepted: 3 February 2014 # Springer-Verlag Berlin Heidelberg 2014
Tuberculosis (TB) is a major global health problem and the burden remains enormous. In 2012, an estimated 8.6 million people developed TB (13% with human immunodeficiency virus [HIV] co-infection) and 1.3 million died from the disease [1]. Most cases were in the Southeast Asia, Africa and Western Pacific regions [1]. About 3.6% of newly diagnosed TB cases and 20% of people previously treated for TB have multidrug-resistant TB [1]. Among children younger than 15 years, there were an estimated 530,000 TB cases and 74,000 TB deaths in 2012 [1]. Children with pulmonary tuberculosis present with nonspecific respiratory symptoms, which are hard to differentiate from other causes, posing a diagnostic challenge. A culture is the definitive diagnostic tool but not routinely attempted because children do not produce enough sputum for examination. A positive tuberculin skin test suggests infection but cannot differentiate quiescent from active disease state, and a negative test does not exclude TB. Xpert MTB/RIF, which is a rapid molecular diagnostic test, has been endorsed by the World Health Organization (WHO) and is rapidly being adopted in various countries for detection of mycobacterium TB (MTB), including rifampicin-resistant types (RIF) [1, 2]. In children, Xpert MTB/RIF has been found to be more sensitive than smear microscopy, but a negative test does not exclude a diagnosis of pulmonary TB; the test is unable to identify 20–25% of children with culture-confirmed TB [3, 4]. The generally low mycobacterial load in respiratory samples
B. F. Laya (*) St. Luke’s Medical Center – Global City, 32nd Street Bonifacio Global City, Taguig City, Philippines 1634 e-mail: [email protected] A. Dehaye World Federation of Pediatric Imaging (WFPI), Reston, VA, USA
of children seems to be a limiting factor for assays, including MTB/RIF [5]. It is also important to identify TB infection and disease among HIV-infected children. This helps in the medical decision-making and management, which includes initiation of antiretroviral therapy and isoniazid preventive therapy. Optimal use of available diagnostics improves active case detection, but there remains an urgent need to develop cheaper and more sensitive point-of-care diagnostic tests, particularly for younger children. Medical imaging methods are important for the diagnosis and thorough evaluation of TB, which have important treatment implications. The chest radiograph is mostly used because of its wide availability and instantaneous result. A normal chest radiograph cannot exclude presence of pulmonary TB but when positive the findings, although nonspecific, closely reflect the pathological changes of the disease (Figs. 1, 2, and 3). It can help assess complications associated with TB and also detect other underlying pathology, including TB–HIV co-infection. Other important considerations include imparting radiation dose to patient, variability of technique, changing pattern of disease, identification of drug resistance, and inter-observer variability. The World Federation of Pediatric Imaging (WFPI) seeks to create an impact in the global fight against childhood tuberculosis through the use of radiography in low-resource settings. WFPI supports the conversion of existing facilities to digital imaging with operator guidelines and recommendations on radiation safety. Training and education on TB imaging is emphasized and delivered through site visits, regional training exchanges, international training courses and webinars. The WFPI Web site has instructional videos and lectures available on the interpretation of chest radiographs in childhood tuberculosis [6–8]. Although more radiologists in low-resource settings are being identified and trained, WFPI has made it possible for on-site radiologists and radiographers
688
Pediatr Radiol (2014) 44:687–689
Fig. 1 Primary tuberculosis in a 1-year-old boy with chronic cough. a Anteroposterior radiograph of the chest demonstrates opacity on the right middle lobe. b Sagittal radiograph confirms the right middle lobe disease and also shows bulky soft-tissue structure surrounding the hilar region, indicative of lymphadenopathy
to send their images to expert readers in other countries (tele-reading) for a second opinion offered on a volunteer basis to support the diagnosis, detect complications, monitor treatment and diagnose other conditions. WFPI can also facilitate contacts with industry partners, offer on-site access through its Web site training and teaching, facilitate research and publication, and draw on project experiences to develop guidelines and recommendations. The WFPI operates via partnerships with existing health care initiatives. It has an ongoing tuberculosis tele-reading
Fig. 2 Progression of primary tuberculosis. Anteroposterior chest radiograph of a 6-year-old boy with low-grade fever and productive cough reveals complete opacification of the left upper lobe, with cavitation containing an air–fluid level in the apical region. There is also diminished caliber and inferior displacement of the left bronchus, suggesting effacement from adjacent lymphadenopathy or lung parenchymal disease
partnership with Khayelitsha Hospital in South Africa and Médecins Sans Frontières (Doctors without Borders) through its global tele-medicine network. Discussions are also underway with health facilities in Malawi, the National Tuberculosis Programme of Swaziland, Baylor College of Medicine in Texas, Stanford University in California, the Pediatric Tuberculosis European Network (PTBNET) and the U.S. Centers for Disease Control in Atlanta, GA. Tuberculosis will only be defeated by a global alliance, bringing together both private and public health organizations, the pharmaceutical industry and the academe.
Fig. 3 Late sequela of pulmonary tuberculosis. Anteroposterior chest radiograph of a 9-year-old boy shows destruction of the left lung with diminished lung volume, residual fibrosis and pleural thickening as a consequence of delayed treatment for pulmonary tuberculosis. There is deviation of the cardiomediastinal structures to the left
Pediatr Radiol (2014) 44:687–689 Conflicts of interest None
References 1. World Health Organization (2013) The burden of disease caused by TB. In: Global tuberculosis report 2013, pp 6–27. http://apps.who.int/ iris/bitstream/10665/91355/1/9789241564656_eng.pdf. Accessed 21 Jan 2014 2. World Health Organization (2010) Roadmap for rolling out Xpert MTB/RIF for rapid diagnosis of TB and MDR-TB. http://www.who. int/tb/laboratory/roadmap_xpert_mtb-rif.pdf. Accessed 21 Jan 2014 3. Sekadde MP, Wobudeya E, Joloba ML et al (2013) Evaluation of the Xpert MTB/RIF test for the diagnosis of childhood pulmonary tuberculosis in Uganda: a cross-sectional diagnostic study. BMC Infect Dis 13:133
689 4. Nicol MP, Workman L, Isaacs W et al (2011) Accuracy of the Xpert MTB/RIF test for the diagnosis of pulmonary tuberculosis in children admitted to hospital in Cape Town, South Africa: a descriptive study. Lancet Infect Dis 11:819–824 5. Rachow A, Clowes P, Saathoff E et al (2012) Increased and expedited case detection by Xpert MTB/RIF assay in childhood tuberculosis: a prospective cohort study. Clin Infect Dis 54: 1388–1396 6. Andronikou S (2013) Paediatric TB Xrays (part 1) – clues from frontal film by Savvas Andronikou. http://vimeo.com/77954925. Accessed 21 Jan 2014 7. Andronikou S (2013) Paediatric TB Xrays (part 2) – clues from lateral film by Savvas Andronikou. https://vimeo.com/77954926. Accessed 21 Jan 2014 8. Laya BF (2014) Childhood tuberculosis. Available via http://pedrad.org/ Portals/7/Education/Childhood%20TB.%20Feb%202014%20WFPI% 20lite.pdf. Accessed 15 Feb 2014
MINISYMPOSIUM
Partnering to solve the problem of tuberculosis Bernard F. Laya & Amanda Dehaye
Received: 16 November 2013 / Accepted: 3 February 2014 # Springer-Verlag Berlin Heidelberg 2014
Tuberculosis (TB) is a major global health problem and the burden remains enormous. In 2012, an estimated 8.6 million people developed TB (13% with human immunodeficiency virus [HIV] co-infection) and 1.3 million died from the disease [1]. Most cases were in the Southeast Asia, Africa and Western Pacific regions [1]. About 3.6% of newly diagnosed TB cases and 20% of people previously treated for TB have multidrug-resistant TB [1]. Among children younger than 15 years, there were an estimated 530,000 TB cases and 74,000 TB deaths in 2012 [1]. Children with pulmonary tuberculosis present with nonspecific respiratory symptoms, which are hard to differentiate from other causes, posing a diagnostic challenge. A culture is the definitive diagnostic tool but not routinely attempted because children do not produce enough sputum for examination. A positive tuberculin skin test suggests infection but cannot differentiate quiescent from active disease state, and a negative test does not exclude TB. Xpert MTB/RIF, which is a rapid molecular diagnostic test, has been endorsed by the World Health Organization (WHO) and is rapidly being adopted in various countries for detection of mycobacterium TB (MTB), including rifampicin-resistant types (RIF) [1, 2]. In children, Xpert MTB/RIF has been found to be more sensitive than smear microscopy, but a negative test does not exclude a diagnosis of pulmonary TB; the test is unable to identify 20–25% of children with culture-confirmed TB [3, 4]. The generally low mycobacterial load in respiratory samples
B. F. Laya (*) St. Luke’s Medical Center – Global City, 32nd Street Bonifacio Global City, Taguig City, Philippines 1634 e-mail: [email protected] A. Dehaye World Federation of Pediatric Imaging (WFPI), Reston, VA, USA
of children seems to be a limiting factor for assays, including MTB/RIF [5]. It is also important to identify TB infection and disease among HIV-infected children. This helps in the medical decision-making and management, which includes initiation of antiretroviral therapy and isoniazid preventive therapy. Optimal use of available diagnostics improves active case detection, but there remains an urgent need to develop cheaper and more sensitive point-of-care diagnostic tests, particularly for younger children. Medical imaging methods are important for the diagnosis and thorough evaluation of TB, which have important treatment implications. The chest radiograph is mostly used because of its wide availability and instantaneous result. A normal chest radiograph cannot exclude presence of pulmonary TB but when positive the findings, although nonspecific, closely reflect the pathological changes of the disease (Figs. 1, 2, and 3). It can help assess complications associated with TB and also detect other underlying pathology, including TB–HIV co-infection. Other important considerations include imparting radiation dose to patient, variability of technique, changing pattern of disease, identification of drug resistance, and inter-observer variability. The World Federation of Pediatric Imaging (WFPI) seeks to create an impact in the global fight against childhood tuberculosis through the use of radiography in low-resource settings. WFPI supports the conversion of existing facilities to digital imaging with operator guidelines and recommendations on radiation safety. Training and education on TB imaging is emphasized and delivered through site visits, regional training exchanges, international training courses and webinars. The WFPI Web site has instructional videos and lectures available on the interpretation of chest radiographs in childhood tuberculosis [6–8]. Although more radiologists in low-resource settings are being identified and trained, WFPI has made it possible for on-site radiologists and radiographers
688
Pediatr Radiol (2014) 44:687–689
Fig. 1 Primary tuberculosis in a 1-year-old boy with chronic cough. a Anteroposterior radiograph of the chest demonstrates opacity on the right middle lobe. b Sagittal radiograph confirms the right middle lobe disease and also shows bulky soft-tissue structure surrounding the hilar region, indicative of lymphadenopathy
to send their images to expert readers in other countries (tele-reading) for a second opinion offered on a volunteer basis to support the diagnosis, detect complications, monitor treatment and diagnose other conditions. WFPI can also facilitate contacts with industry partners, offer on-site access through its Web site training and teaching, facilitate research and publication, and draw on project experiences to develop guidelines and recommendations. The WFPI operates via partnerships with existing health care initiatives. It has an ongoing tuberculosis tele-reading
Fig. 2 Progression of primary tuberculosis. Anteroposterior chest radiograph of a 6-year-old boy with low-grade fever and productive cough reveals complete opacification of the left upper lobe, with cavitation containing an air–fluid level in the apical region. There is also diminished caliber and inferior displacement of the left bronchus, suggesting effacement from adjacent lymphadenopathy or lung parenchymal disease
partnership with Khayelitsha Hospital in South Africa and Médecins Sans Frontières (Doctors without Borders) through its global tele-medicine network. Discussions are also underway with health facilities in Malawi, the National Tuberculosis Programme of Swaziland, Baylor College of Medicine in Texas, Stanford University in California, the Pediatric Tuberculosis European Network (PTBNET) and the U.S. Centers for Disease Control in Atlanta, GA. Tuberculosis will only be defeated by a global alliance, bringing together both private and public health organizations, the pharmaceutical industry and the academe.
Fig. 3 Late sequela of pulmonary tuberculosis. Anteroposterior chest radiograph of a 9-year-old boy shows destruction of the left lung with diminished lung volume, residual fibrosis and pleural thickening as a consequence of delayed treatment for pulmonary tuberculosis. There is deviation of the cardiomediastinal structures to the left
Pediatr Radiol (2014) 44:687–689 Conflicts of interest None
References 1. World Health Organization (2013) The burden of disease caused by TB. In: Global tuberculosis report 2013, pp 6–27. http://apps.who.int/ iris/bitstream/10665/91355/1/9789241564656_eng.pdf. Accessed 21 Jan 2014 2. World Health Organization (2010) Roadmap for rolling out Xpert MTB/RIF for rapid diagnosis of TB and MDR-TB. http://www.who. int/tb/laboratory/roadmap_xpert_mtb-rif.pdf. Accessed 21 Jan 2014 3. Sekadde MP, Wobudeya E, Joloba ML et al (2013) Evaluation of the Xpert MTB/RIF test for the diagnosis of childhood pulmonary tuberculosis in Uganda: a cross-sectional diagnostic study. BMC Infect Dis 13:133
689 4. Nicol MP, Workman L, Isaacs W et al (2011) Accuracy of the Xpert MTB/RIF test for the diagnosis of pulmonary tuberculosis in children admitted to hospital in Cape Town, South Africa: a descriptive study. Lancet Infect Dis 11:819–824 5. Rachow A, Clowes P, Saathoff E et al (2012) Increased and expedited case detection by Xpert MTB/RIF assay in childhood tuberculosis: a prospective cohort study. Clin Infect Dis 54: 1388–1396 6. Andronikou S (2013) Paediatric TB Xrays (part 1) – clues from frontal film by Savvas Andronikou. http://vimeo.com/77954925. Accessed 21 Jan 2014 7. Andronikou S (2013) Paediatric TB Xrays (part 2) – clues from lateral film by Savvas Andronikou. https://vimeo.com/77954926. Accessed 21 Jan 2014 8. Laya BF (2014) Childhood tuberculosis. Available via http://pedrad.org/ Portals/7/Education/Childhood%20TB.%20Feb%202014%20WFPI% 20lite.pdf. Accessed 15 Feb 2014
