Brief tale of a bacteraemia by Rhodococcus equi with concomitant lung mass: what came first, the chicken or the egg?

摘要

Rhodococcus equi is an uncommon Gram positive, variably acid-fast agent of infections, that appear as hard to treat mostly owing to the establishment of intracellular niches. Also, the lack of criteria to interpret susceptibility testing may lead to under-reporting or overestimation of resistance expression. Finally, the knowledge about this pathogen’s clinical impact may be affected by wrong characterization at a genus and species level provided by phenotype-based assays. We present the case of a bacteraemia with a concomitant lung mass in a lymphoma patient, that further highlights the emergence of rhodococcal diseases as a matter for concern in the field of infectious diseases and haematology.