Nocardia thailandica Pulmonary Nocardiosis in a Post-Solid Organ Transplant Patient

Nocardia thailandica is a rare pathogen related to Nocardia asteroides, Nocardia neocaledoniensis, and Nocardia caishijiensis that, since its original description in 2004, has only been reported to cause wound and ocular infections in humans. We report a case of pulmonary nocardiosis caused by Nocardia thailandica in a 66-year-old solid organ transplant patient from Connecticut, which was identified at the molecular taxonomic level by secA1 analysis, 16S rRNA gene sequencing, and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). To our knowledge, this is the first reported case of N. thailandica in the United States and the first report of pulmonary infection by this pathogen in the literature.