1
|
Drancourt M, Djemai K, Gouriet F, Grine G, Loukil A, Bedotto M, Levasseur A, Lepidi H, Bou-Khalil J, Khelaifia S, Raoult D. Methanobrevibacter smithii archaemia in febrile patients with bacteremia, including those with endocarditis. Clin Infect Dis 2020; 73:e2571-e2579. [PMID: 32668457 DOI: 10.1093/cid/ciaa998] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 07/10/2020] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND The spectrum of infections caused by the emerging opportunistic pathogens methanogens which escape routine detection remains to be described. To determine the prevalence of archaemia, we searched for methanogens in the blood of febrile patients using specific tools. METHODS We conducted a prospective study at Institut Hospitalier Universitaire Méditerranée Infection, Marseille, France, September 2018 - April 2020, enrolling 7,716 blood culture samples routinely collected in patients with fever. Blood samples were screened by specific PCR assays for the presence of methanogens. Positive samples were observed by autofluorescence and electron microscopy, analyzed by metagenomics and cultured using previously developed methods. Blood culture bottles experimentally inoculated were used as controls. The presence of methanogens in vascular and cardiac tissues was assessed by indirect immunofluorescence, fluorescent in situ hybridization and PCR-based investigations. RESULTS PCR detection attempted in 7,716 blood samples, was negative in all 1,312 aerobic bottles and 810 bacterial culture-negative anaerobic bottles. PCRs were positive in 27/5,594 (0.5%) bacterial culture-positive anaerobic bottles that contained cultures collected from 26 patients. Sequencing confirmed Methanobrevibacter smithii associated with staphylococci in 14 patients, fermentative Enterobacteriaceae in nine patients and streptococci in three patients. Metagenomics confirmed M. smithii in five blood samples, and M. smithii was isolated via culture in broth from two samples; the genomes of these two isolates were sequenced. Blood cultures experimentally inoculated with Enterobacteriaceae, Staphylococcus epidermidis or Staphylococcus hominis yielded hydrogen, but no methane, authentifying observational data.Three patients, all diagnosed with infectious mitral endocarditis, were diagnosed by microscopy, PCR-based detections and culture: we showed M. smithii microscopically and by a specific PCR followed by sequencing method in two of three cardiovascular tissues. CONCLUSIONS Using appropriate methods of detection, M. smithii is demonstrated as causing archaemia and endocarditis in febrile patients who are coinfected by bacteria.
Collapse
Affiliation(s)
- Michel Drancourt
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Kenza Djemai
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France.,IHU Méditerranée Infection, Marseille, France
| | - Frédérique Gouriet
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Ghiles Grine
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France.,IHU Méditerranée Infection, Marseille, France
| | - Ahmed Loukil
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Marielle Bedotto
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Anthony Levasseur
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Hubert Lepidi
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
| | | | | | - Didier Raoult
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
| |
Collapse
|