Interferon gamma blood tests don’t require patients to return to the office to gather results, and there are no BCG or skin placement issues. However, results may vary widely, and the test is not useful in children five years of age or younger, he added.
Patients taking anti-TNFα therapies who develop latent TB may exhibit symptoms like persistent fever, weight loss, and cough. In these cases, chest radiographs, complete blood count, or CT scans may help confirm diagnosis, Dr. Ampel said. In a patient with suspected active tuberculosis, first establish diagnosis, then halt anti-TNF therapy, then start treating the TB, he said. If rheumatoid arthritis flares at some point, rheumatologists may wish to restart BRMs and watch the patient carefully.
Be aware that other, nontuberculosis mycobacteria may also cause infection in these patients, Dr. Ampel added. “Non-TB mycobacteria live in the environment, and we are exposed to them all the time.”