Delays in the diagnosis of pulmonary tuberculosis in Coahuila, Mexico

To determine diagnostic delay in pulmonary tuberculosis (PTB) cases and analyse associated factors.

New PTB cases were studied in Coahuila, Northern Mexico, between 2008 and 2009. We obtained census data and data on residential address, symptoms and diagnosis from the national patient database; sociodemographic variables were obtained during home visits. Bivariate analyses used the Kaplan-Meier method; multivariate analysis consisted of modelling survival.

We studied 458 subjects (median age 48 years), who were predominantly males (56.1%); the median years of schooling was 6.0 years, 83.4% were urban residents, 50.3% were unemployed, and 87.7% suffered from food poverty. The median delay between the onset of symptoms and the first medical consultation was 53.5 days. Lack of formal education (P = 0.050) and living ≥5 km from a health unit (P = 0.034) were associated with longer delays and consequently with severe symptoms (cough ≥2 weeks, P = 0.001; chest pain, P = 0.032; malnutrition, P = 0.003). Mean health system delay (between first consultation and smear test result) was 18.5 days, and was significantly longer when the first consultation was with a private physician (P < 0.001) and when patient age was ≥46 years (P = 0.001).

In Coahuila, lack of formal education, living ≥5 km from a health unit, first consultation with a private physician, and being aged ≥46 years contributed to delays in PTB diagnosis.