<i>Mycobacterium conceptionense</i> Bloodstream Infection in a Patient with Advanced Gastric Carcinoma

Abstract

SUMMARY:A 65-year-old Japanese male farmer with advanced gastric adenocarcinoma and multiple hepatic metastases was admitted to our hospital. Blood culture results were positive on day 5, and Gram-positive rods were detected. According to the results of Ziehl-Neelsen staining and a cultured colony of this bacterium, we suspected a mycobacterial infection. Suspecting a rapidly growing mycobacterium (RGM), we started multidrug therapy with levofloxacin, clarithromycin, and ethambutol, and the patient recovered from the bloodstream infection. Further gene examination (16S rRNA, hsp65, and sodA) revealed an isolate of Mycobacterium conceptionense. M. conceptionense was first identified as an RGM in 2006. Among previous case reports of M. conceptionense infections, bone and soft tissue infections in hosts with a disorder of the normal structure (e.g., surgical sites) were dominant. We report the characteristics of M. conceptionense infection in this first Japanese case report and a review of the literature.Non-tuberculous mycobacteria (NTM) are the causative pathogens in pneumonia, osteomyelitis, lymphadenitis, and bacteremia, particularly in immunocompromised hosts. The most common pathogens in Japan are Mycobacterium avium complex (MAC) (approximately 70-80z) and Mycobacterium kansasii (approximately 10-20z) (1); however, the prevalence of rapidly growing mycobacteria (RGM) is increasing.

Clusters of nontuberculous mycobacteria linked to water sources at three Veterans Affairs medical centers

“…Little has been published on the infectious potential of M. conceptionense, although several case reports have described soft-tissue, pulmonary, and bloodstream infections. [18][19][20][21][22][23][24][25] Despite removal of the VAMC A ICU ice machine that grew M. conceptionense in 2016, an additional case with the identical strain of M. conceptionense occurred on May 8, 2017, in a patient housed in the VAMC A ICU. No definitive M. conceptionense water source for VAMC B was found.…”

Mycobacterium senegalense Infection in Kidney Transplant Patient with Diabetes, Memphis, Tennessee, USA

“…Only a handful of M. conceptionense cases are readily identifiable in existing literature. Infections can manifest with pulmonary involvement but more commonly manifest as skin or subcutaneous infection, such as after face rejuvenation surgery, breast augmentation surgery, gastric carcinoma resection, or subcutaneous ankle infection (3)(4)(5)(6). Mycobacterial species like M. senegalense have been found in irrigation systems, soil, domestic and wild animals, and dairy products (7,8).…”