[Respiratory isolation in suspected tuberculosis with negative direct sputum examination]

Airborne isolation is the main confinement measure used to limit human-to-human transmission of tuberculosis. If implemented early, precisely as soon as the patient is clinically diagnosed with tuberculosis, this measure will protect the population, particularly the health workers who are exposed. A patient suspected of being infected with tuberculosis can create a difficult situation if microbiological examination of his respiratory secretions is negative. This is a complex laboratory technique and sensitivity varies from one test to another. Thus, a false negative result is possible; meaning that a patient can have positive results on a microbiological culture performed later. This patient would still have low, but not no, contagiousness as long as a treatment has not been initiated. This situation can extend the period of respiratory isolation while further diagnostic investigations are carried out. This extended isolation can reduce the quality of health care delivered and patients can show signs of depression and anxiety. The use in routine clinical investigation of gene amplification tools should allow a rethinking of respiratory isolation rules. These tools, which are very sensitive and with a short reporting time, could drastically reduce the duration of respiratory isolation for patients suspected of being infected with tuberculosis.