Elusive Enterobacter cloacae causing pacemaker endocarditis

An 80-year-old patient was admitted for fever, chills, and chest wall pain. He had a past medical history significant for heart failure with a cardiac resynchronization therapy pacemaker implantation. Extensive workup revealed Enterobacter cloacae endocarditis of the pacemaker leads and the mitral valve, a rare etiology with an unidentified source in our patient. He was managed with a rather unconventional method which proved to be successful. This case sheds light on non-HACEK (other than Haemophilus spp., Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, or Kingella spp). gram-negative organisms, and particularly E. cloacae, as uncommon causes of endocarditis with elevated mortality, and discusses potential treatment modalities.