Infective Endocarditis by Clostridioides and Clostridium Species-A Narrative Review

Bacteria of the genus Clostridium are anaerobic Gram-positive spore-forming bacilli that include more than 200 species. Some of them are known to cause invasive infections and diseases caused by the production of toxins. Some of the diseases that are mediated by toxins are colitis in patients with specific risk factors, such as previous administration of antimicrobials or foodborne botulism. Invasive diseases include bacteremia, infective endocarditis (IE), clostridial myonecrosis (gas gangrene), and other diseases that involve the destruction of soft tissue due to the local production of toxins. The present study aimed to review all cases of IE by Clostridioides and Clostridium species and describe the epidemiology, clinical characteristics, treatment, and outcomes of these infections. A narrative review was performed based on a search in PubMed and Scopus for studies published until 11 September 2023, providing such data of IE caused by Clostridioides and Clostridium species in humans. A total of 20 studies containing data for 21 patients were included. A prosthetic valve was present in 5 patients (23.8%). The aortic valve was the most commonly involved, followed by the mitral valve. Fever, sepsis, and embolic phenomena were the most common clinical presentations. Beta-lactams and metronidazole were the most commonly used antimicrobials. Surgery was performed in nine patients (45%). Mortality reached 33.3%. IE in multiple valves was associated with increased mortality. Despite the heterogeneous genetic and molecular characteristics that necessitate the taxonomic change of some of this genus's previous members, the clinical syndrome of IE caused by these bacteria seems to have similar characteristics.

Clostridioides difficile from intracardiac vegetation

Extracolonic manifestations by Clostridioides difficile are uncommon. Here, we report a case of monomicrobial C. difficile intracardiac vegetation in a 11-year-old girl with a predisposed heart disease who responded well to the treatment. C. difficile has been isolated from a variety of specimens outside the intestinal tract and is not always associated with gastrointestinal symptoms.

Brain abscess and cervical lymphadenitis due to Paraclostridium bifermentans: A report of two cases

Paraclostridium bifermentans (current nomenclature of Clostridium bifermentans since 2016) is a gram-positive, spore-forming anaerobic bacterium. Here, we describe two cases associated with this organism. The first, primarily a case of tubercular brain abscess where P. bifermentans was isolated as part of a polymicrobial flora, following a neurosurgical procedure for the same and the second, a case of cervical lymphadenitis from which it was isolated as the sole causative agent. There are only a few reported cases of P. bifermentans in literature and these cases illustrate the widening spectrum of infections related to it.