Active Case Finding of Pulmonary Tuberculosis through Screening of Respiratory Symptomatics Using Sputum Microscopy: Is It Time to Change the Paradigm?
Background. One of the main strategies for the early detection of pulmonary tuberculosis (PTB) is through the screening of individuals with symptoms compatible with PTB. Although this is programmatic strategy for active case finding, its yield is not well known. Objective. To determine the yield of pulmonary tuberculosis active case finding through the screening of respiratory symptomatic (RS) patients at a general hospital. Methods. RS patients were defined as subjects complaining of cough and/or sputum for a period of 2 or more weeks. Outpatients and their companions were approached while they waited in the outpatient care areas of the hospital to detect RS. Two samples from different days or 2 samples taken 2 hours apart on the same day were collected. Results. 122 RS patients were identified. Fifty-seven patients (46.7%) had at least one sputum sample analyzed. Three patients presented a positive smear and 2 were culture positive; neither had upper airway symptoms. None of the patients with productive cough and upper airway symptoms had a positive smear ( ). Only 19 (33.3%) returned to the laboratory to retrieve their results. Conclusion. Current strategy to screen RS patients based only on clinical data has a low compliance. Specific strategies to increase compliance (removal of barriers, incentives, etc.) should be implemented. 1. Introduction Tuberculosis (TB) represents one of the world’s public health greatest challenges. One key factor for its control is to stop the chain of transmission in the community by diagnosing and treating cases as early as possible. The planning and implementation of efficient tuberculosis control programs is crucial, and the strategies that compose them must be submitted to constant evaluation and refining. One of the main strategies for the early detection of pulmonary tuberculosis (PTB) is through the screening of individuals with symptoms compatible with PTB (in México for screening purposes defined as productive cough lasting more than two weeks), known also as respiratory symptomatic patients (RS). It is estimated that in regions with high prevalence of PTB from 5 to 10% of the patients that seek outpatient medical services are RS, and, of those, from 1 to 5% are smear positive [1]. The most recent data from Mexico [2] shows a PTB incidence of 42.1/100,000 in the state of Baja California, the highest rate in the country; Tijuana the largest city in the state has an annual rate between 50 and 60 cases per 100,000. Most of the cases were detected passively at outpatient health services and hospitals; only 3.6%
References
[1]
V. Farga and J. Caminero, Tuberculosis, Mediterranean Editorial, 3rd edition, 2011.
[2]
SINAVE/DGE/SALUD/Información Epidemiológica de morbilidad, Anuario Ejecutivo, 2010.
[3]
M. A. Vaca-Marín, C. Tlacahuac-Cholula, and R. Olvera-Castillo, “Pulmonary Tuberculosis among respiratory symptomatics detected in SSA health units in the state of Tlaxcala, Mexico,” Revista del Instituto Nacional de Enfermedades Respiratorias Mexico, vol. 12, pp. 29–34, 1999.
[4]
S. R. Mase, A. Ramsay, V. Ng et al., “Yield of serial sputum specimen examinations in the diagnosis of pulmonary tuberculosis: a systematic review,” International Journal of Tuberculosis and Lung Disease, vol. 11, no. 5, pp. 485–495, 2007.
[5]
S. Hirao, M. A. Yassin, H. G. Khamofu et al., “Same-day smears in the diagnosis of tuberculosis,” Tropical Medicine and International Health, vol. 12, no. 12, pp. 1459–1463, 2007.
[6]
American Thoracic Society, “Diagnostic standards and classification of tuberculosis in adults and children,” American Journal of Respiratory and Critical Care Medicine, vol. 161, pp. 1376–1395, 2000.
[7]
S. C. Henao-Riveros, C. R. Sierra-Parada, E. A. Sánchez-Morales, and A. Saavedra-Rodríguez, “Búsqueda de tuberculosis en pacientes sintomáticos respiratorios en cuatro hospitales de Bogotá DC,” Revista Espa？ola de de Salud Pública, vol. 9, pp. 408–419, 2007.
[8]
Programa de Accion, “Tuberculosis, Secretaria de salud—Subsecretaria de prevencion y proteccion de la salud,” Primera Edición, 2001.
[9]
“Manuales de Capacitacion para el Manejo de la Tuberculosis. Módulo 2: Detección de casos tuberculosis,” Primera Edición. Partners in Health y Ministerio de Salud, Perú, 2006.
[10]
E. M. Julia Inés, M. O. William, and G. L. Julio César, “Active research of respiratory symptomatic patients in high-risk population for tuberculosis,” Revista Facultad Nacional de Salud Pública, vol. 21, pp. 9–20, 2003.
[11]
M. F. Iademarco, O. Grady J, and K. L？nnroth, “Chest radiography for tuberculosis screening is back on the agenda,” The International Journal of Tuberculosis and Lung Disease, vol. 16, pp. 1421–1422, 2012.
[12]
A. Story, R. W. Aldridge, I. Abubakar et al., “Active case finding for pulmonary tuberculosis using mobile digital chest radiography: an observational study,” The International Journal of Tuberculosis and Lung Disease, vol. 16, pp. 1461–1467, 2012.
[13]
T. R. Sterling, P. A. Pham, and R. E. Chaisson, “HIV infection-related tuberculosis: clinical manifestations and treatment,” Clinical Infectious Diseases, vol. 50, no. 3, pp. S223–S230, 2010.
[14]
A. H. van’t Hoog, H. K. Meme, K. F. Laserson et al., “Screening strategies for tuberculosis prevalence surveys: the value of chest radiography and symptoms,” PLoS ONE, vol. 7, no. 7, Article ID e38691, 2012.
[15]
M. R. Coulborn, I. Panunzi, S. Spijker et al., “Feasibility of using teleradiography to improve tuberculosis screening and case management in a district hospital in Malawi,” Bulletin of the World Health Organization, vol. 90, pp. 705–711, 2012.
