A case of Mycobacterium goodii prosthetic valve endocarditis in a non-immunocompromised patient: use of 16S rDNA analysis for rapid diagnosis

BACKGROUND: Mycobacterium goodii is a rare cause of significant infection. M. goodii has mainly been associated with lymphadenitis, cellulitis, osteomyelitis, and wound infection. CASE PRESENTATION: A case of a 76-year-old Caucasian female is presented. The patient developed a prosthetic valve endocarditis caused by M. goodii. She had also suffered from severe neurological symptoms related to a septic emboli that could be demonstrated as an ischemic lesion found on CT of the brain. Transesophageal echocardiography verified a large vegetation attached to the prosthetic valve. Commonly used blood culture bottles showed growth of the bacteria after 3 days. CONCLUSIONS: Although M. goodii is rarely involved in these kinds of severe infections, rapidly growing mycobacteria should be recognized during conventional bacterial investigations and identified by molecular tools such as analysis of 16S rDNA. Species identification of nontuberculous mycobacteria is demanding and is preferably done in collaboration with a mycobacterial laboratory. An early diagnosis provides the opportunity for adequate treatment. In the present case, prolonged antimicrobial treatment and surgery with replacement of the prosthetic valve was successful.