Sensitivity and Specificity of Oral Urea Breath Testing for Presumptive Diagnosis and Treatment Response in Pulmonary Tuberculosis in Bamako, Mali

Background:

• Tuberculosis is a disease of the lungs caused by the bacteria Mycobacterium tuberculosis (M. tuberculosis). The most popular and least expensive tool used to detect the presence of the tuberculosis bacteria is called sputum smears, which is a lab test used to look for bacteria in the sputum via a microscope. However, the test s results are not always accurate, and the test cannot determine if the bacteria will be resistant to standard tuberculosis treatments. The most sensitive test currently available is called sputum culture, in which a sputum sample is used to check for the growth of tuberculosis bacteria. However, this test takes at least a month to produce accurate results, and requires expensive equipment that is not available in many countries where M. tuberculosis is found.
• The urea breath test (UBT) has been used to detect infection with Helicobacter pylori, a bacteria associated with stomach ulcers, by testing individual breath samples. Researchers are interested in determining whether breath samples can also be used to detect the presence of M. tuberculosis in the lungs of subjects with tuberculosis, and to see if tuberculosis treatments are successful.

Objectives:

• To assess the sensitivity and specificity of urea breath testing in the diagnosis and treatment response of pulmonary tuberculosis.

Eligibility:

• Individuals at least 18 years of age who either have been diagnosed with tuberculosis or are healthy volunteers with no past history of tuberculosis.
• The study will be conducted in Bamako, Mali.

Design:

• This study will involve three groups: two pilot groups of individuals who have already been diagnosed with tuberculosis, and a primary study group of both healthy volunteers and individuals who have been diagnosed with tuberculosis.
• Participants will be screened with a physical examination and medical history, as well as blood, sputum, stool, and urine samples.
• First pilot group (one visit):
• Participants should not eat, drink, or smoke for at least 1 hour prior to the UBT test.
• Participants will provide a baseline exhaled air sample, and then will receive the UBT test, which involves a dose of Pranactin -Citric dissolved in water. Additional exhaled air samples will be collected at eight time points (10, 20, 45, 60, 90, 120, 180, and 240 minutes after the dose).
• Second pilot group (one or two visits):
• Participants should not eat, drink, or smoke for at least 1 hour prior to the UBT test.
• Participants will provide a baseline exhaled air sample, and then will receive the UBT test. Half of the participants will receive a dose of bismuth (Pepto-Bismol) prior to collection of air samples to see how this affects the results of the UBT test. Additional exhaled air samples will be collected at three time points specified by the study researchers.
• On the following day, participants will return for a second visit to provide three more exhaled air samples.
• Primary study group (five visits for participants with tuberculosis, two visits for healthy volunteers):
• All participants will have two visits, following the procedures given for the second pilot group. Half will receive a dose of bismuth prior to collection of air samples.
• Participants with tuberculosis will have three additional visits (days 6, 10, and 16 following the first study visit) to provide additional sputum and exhaled air samples to monitor the progress of tuberculosis treatment.