An Investigation of Extensively Drug - resistant Tuberculosis: Revealing Potential Improvements for Tuberculosis Control Program

Abstract

On 31 May 2019, the Division of Epidemiology (DoE) was notified of a confirmed extensively drug-resistant tuberculosis (XDR-TB) case in Bangkok. The DoE and local teams conducted a joint investigation to describe the epidemiological characteristics of the case, identify possible source cases and contacts, and implement control measures. A descriptive study was performed among cases and close contacts by interviewing and reviewing the medical records using a standard case definition. An environmental study was performed at the case's house, workplaces, and tuberculosis (TB) clinic. The TB drugs were tested to analyze the content of active ingredients and dissolution. The case was a 36-year-old Thai male. In 2011, he was diagnosed with pulmonary tuberculosis and had received inappropriate treatment. He developed multidrug-resistant tuberculosis (MDR-TB) eight months later and XDR-TB in May 2019 with delayed hospital admission. Two possible source cases, both co-workers of the index case, were identified. Of 21 contacts, 13 were screened with a chest x-ray and found to have no abnormality. At the TB-clinic, drugs were stored in a room with inappropriate levels of temperature and humidity; however, the content of active ingredients and dissolution of TB drugs were within normal limits. Early hospital admission and monitoring of drug stockpile environments according to standard guidelines are recommended.