Methanobrevibacter smithii tonsillar phlegmon: a case report

Abstract

Untreated tonsillar phlegmon is a life-threatening condition commonly caused by Streptococcus pyogenes and Fusobacterium necrophorum , among other pathogens. Here, using specific laboratory tools, we detected Methanobrevibacter smithii in addition to S. pyogenes . This unprecedented observation questions the role of methanogens in phlegmon and the optimal treatment of this mixed infection.

Archaea in the Human Microbiome and Potential Effects on Human Infectious Disease

“…Tonsillar phlegmon, a retropharyngeal abscess, mainly affects adolescents and young adults and is caused by an infection originating from the peritonsillar space and the pharyngeal sphincter. The infection can spread to adjacent tissues and, if not treated promptly, this condition, which often involves pathogens such as Streptococcus pyogenes and Fusobacterium necrophorum , can escalate and become a serious threat ( 32 ).…”

“…Within tonsillar phlegmon, archaea, particularly M. smithii , may foster the growth of pathogenic bacteria through syntrophic interactions. In addition, archaeal methanogenesis activity, leading to methane (CH 4 ) production, could contribute to radiologically visible gas in tonsillar phlegmon cases ( 32 ). Djemai et al identified M. smithii using 16S rRNA gene sequencing with coexisting bacteria commonly found in M. smithii co-infections.…”