Gemella haemolysans spondylodiscitis: a report of two cases

The First Case of Infectious Spondylitis Caused by Gemella bergeri

Gemella bergeri, a member of the genus Gemella, is a facultatively anaerobic, Gram-positive cocci. G. bergeri is a component of normal oral flora; however, it can become pathogenic and cause infections in patients with poor oral hygiene. A 78-year-old man was admitted to a hospital with a complaint of increasing posterior neck pain and lower back pain for 2 weeks. MRI was suggestive of infectious spondylitis at the C3-C4 level with prevertebral abscess formation, anterior epidural abscess formation. We identified Gemella bergeri in closed pus obtained during the surgery. Herein, we describe the first case of infective spondylitis caused by G. bergeri.

Gemella haemolysans bacteremia in a patient with secondary peritonitis due to a duodenal ulcer perforation: A case report

We describe a case of Gemella haemolysans septic shock in a 75-year old Japanese male with a duodenal perforation and secondary peritonitis. Blood cultures on admission were positive for Gram-positive and Gram-variable cocci, and G. haemolysans was identified using whole cell matrix-assisted laser desorpition/ionization mass spectrometry (MALDI-TOF MS), with a score value of 2.12. The 16S rRNA sequencing was difficult to use as a diagnostic test because there was more than 99% sequence homology with related bacterial strains. Based on both the biochemical profiles and whole groEL sequence, we concluded that the strain in our patient was G. haemolysans. The patient was successfully treated with a 16-day course of antimicrobials. His clinical condition improved, and no evidence of a relapse of the infection was noted. Although MALDI-TOF MS and 16S rRNA sequencing are useful for identification of the species, the basic biochemical profile is also important to identify a rare species.

Metagenomic sequencing of bile from gallstone patients to identify different microbial community patterns and novel biliary bacteria

Despite the high worldwide prevalence of gallstone disease, the role of the biliary microbiota in gallstone pathogenesis remains obscure. Next-generation sequencing offers advantages for systematically understanding the human microbiota; however, there have been few such investigations of the biliary microbiome. Here, we performed whole-metagenome shotgun (WMS) sequencing and 16S rRNA sequencing on bile samples from 15 Chinese patients with gallstone disease. Microbial communities of most individuals were clustered into two types, according to the relative enrichment of different intestinal bacterial species. In the bile samples, oral cavity/respiratory tract inhabitants were more prevalent than intestinal inhabitants and existed in both community types. Unexpectedly, the two types were not associated with fever status or surgical history, and many bacteria were patient-specific. We identified 13 novel biliary bacteria based on WMS sequencing, as well as genes encoding putative proteins related to gallstone formation and bile resistance (e.g., β-glucuronidase and multidrug efflux pumps). Bile samples from gallstone patients had reduced microbial diversity compared to healthy faecal samples. Patient samples were enriched in pathways related to oxidative stress and flagellar assembly, whereas carbohydrate metabolic pathways showed varying behaviours. As the first biliary WMS survey, our study reveals the complexity and specificity of biliary microecology.

Recurrent Gemella haemolysans meningitis in a patient with osteomyelitis of the clivus

Systemic infection caused by G. haemolysans has rarely been reported. We herein describe the case of a 69-year-old woman with recurrent G. haemolysans meningitis that led to abducens nerve palsy. Osteomyelitis of the clivus was likely present at the first admission, which led to reinfection of the meninges because the course of antibiotic treatment was too short. The patient has remained free of relapse for one year after undergoing a second round of treatment that lasted 63 days. In cases of G. haemolysans meningitis, coexisting infectious diseases, such as endocarditis and/or osteomyelitis, should therefore be investigated to prevent recurrence.