Immunocompetent patients with pulmonary Mycobacterium kansasii infection: A case series and review of the literature

We describe four patients who presented with suspected symptomatic pulmonary tuberculosis but were found to suffer from Mycobacterium kansasii infection, with a clinical and radiologic pattern that was indistinguishable from that of Mycobacterium tuberculosis infection. We review the literature as well as the current guidelines, excluding HIV-infected patients. We point out that a patient with clinically suspected pulmonary tuberculosis found to be infected by mycobacterium other than tuberculosis (MOTT), such as M. kansasii, is not considered in the American Thoracic Society guideline for MOTT.