Pericardial infection caused by Brevibacterium casei

Phenotypic and genomic characteristics of Brevibacterium zhoupengii sp. nov., a novel halotolerant actinomycete isolated from bat feces

Two strictly aerobic, Gram-staining-positive, non-spore-forming, regular rod-shaped (approximately 0.7 × 1.9 mm) bacteria (HY170^T and HY001) were isolated from bat feces collected from Chongzuo city, Guangxi province (22°20′54″N, 106°49′20″E, July 2011) and Chuxiong Yi Autonomous Prefecture, Yunnan province (25°09′10″N, 102°04′39″E, October 2013) of South China, respectively. Optimal growth is obtained at 25–28°C (range, 4–32°C) on BHI-5% sheep blood plate with pH 7.5 (range, 5.0–10.0) in the presence of 0.5–1.0% NaCl (w/v) (range, 0–15% NaCl [w/v]). The phylogenetic and phylogenomic trees based respectively on the 16S rRNA gene and 845 core gene sequences revealed that the two strains formed a distinct lineage within the genus Brevibacterium, most closely related to B. aurantiacum NCDO 739^T (16S rRNA similarity, both 98.5%; dDDH, 46.7–46.8%; ANI, 91.9–92.1%). Strain HY170^T contained MK-8(H₂), diphosphatidylglycerol (DPG) and phosphatidylglycerol (PG), galactose and ribose as the predominant menaquinone, major polar lipids, and main sugars in the cell wall teichoic acids, respectively. The meso-diaminopimelic acid (meso-DAP) was the diagnostic diamino acid of the peptidoglycan found in strain HY170^T. Anteiso-C_15:0 and anteiso-C_17:0 were the major fatty acids (> 10%) of strains HY170^T and HY001, with anteiso-C_17:1A predominant in strain HY170^T but absent in strain HY001. Mining the genomes revealed the presence of secondary metabolite biosynthesis gene clusters encoding for non-alpha poly-amino acids (NAPAA), ectoine, siderophore, and terpene. Based on results from the phylogenetic, chemotaxonomic and phenotypic analyses, the two strains could be classified as a novel species of the genus Brevibacterium, for which the name Brevibacterium zhoupengii sp. nov. is proposed (type strain HY170^T = CGMCC 1.18600^T = JCM 34230^T).

Successful Treatment of Brevibacterium Bacteremia Solely With Antimicrobial Therapy

Brevibacterium is a large genus that is not often involved in pathogenesis, however, since 1991 there have been several case reports of Brevibacterium-associated illness, most often due to bacteremia in the setting of an immunocompromised patient with a central venous catheter (CVC). Here we detail the case of an elderly woman with many comorbidities and a peripherally inserted central catheter (PICC) line for over four years, who presented with septic shock and Brevibacterium bacteremia. In nearly all previous cases of Brevibacterium bacteremia it was thought to be due to a CVC which was removed as part of the treatment in conjunction with antibiotics. In this case, the patient was treated with empiric antibiotics and her blood cultures cleared within 48 hours without catheter removal or antibiotic-lock therapy. The clinical outcome was favorable at 50 days follow-up.

A Catheter-Related Bloodstream Infection by Brevibacterium casei in a Child with Acute Myeloid Leukemia: Case Report and Literature Review

The most common organisms isolated from pediatric catheter-related bloodstream infections (CRBSIs) are Gram-positive cocci, such as coagulase-negative staphylococci and Staphylococcus aureus. There are few formal reports of Brevibacterium casei infection and even fewer reports of CRBSI due to this Gram-positive rod. Here we report the first case of CRBSI due to B. casei in an 8-year-old girl with acute myeloid leukemia in Japan. The isolate exhibited decreased susceptibility to ß-lactam antibiotics. Antimicrobial therapy with meropenem and vancomycin, in addition to the removal of central venous catheter line, consequently led to a significant clinical improvement of the patient's symptoms. A literature review found available clinical courses in 16 cases (4 pediatric cases including our case) of B. casei infection. Our case and those in literature suggested that B. casei infection often occurs in patients with indwelling central venous catheters; the literature review further suggested that removal of central venous catheters is required in most cases. Special attention should be paid to the detection of opportunistic infections due to Brevibacterium spp. in immunocompromized children who are using a central venous catheter.

Brevibacteria tibial osteomyelitis

Brevibacteria are Gram-positive rods found in human skin flora and dairy products. Although generally not considered human pathogens, case reports have implicated Brevibacterium species as rare causes of bacteremia, endocarditis, peritonitis, and osteomyelitis. We report a case of Brevibacterium tibial osteomyelitis in an immunocompetent individual with implanted hardware and highlight the challenge of identifying the organism and recognizing it as a potential pathogen.

Brevibacterium massiliense bacteremia

Brevibacterium massiliense infection in man is rare. We report here the second case with isolation of B. massiliense in human. This micro-organism requires specific laboratory investigations such as 16S rRNA gene sequencing for accurate species identification. The clinical outcome was favorable.

Measuring the Level of Agreement Between Cloacal Gram's Stains and Bacterial Cultures in Hispaniolan Amazon Parrots ( Amazona ventralis )

Cloacal or fecal Gram's stains and bacterial cultures are routinely performed during avian physical examinations to assess the microbial flora of the gastrointestinal tract. Although cloacal or fecal Gram's stains and bacterial cultures are considered routine diagnostic procedures, the level of agreement between the individual tests has not been determined. To investigate the level of agreement between results from Gram's stain and bacterial culture when used to assess cloacal or fecal samples from psittacine birds, samples were taken from 21 clinically healthy Hispaniolan Amazon parrots ( Amazona ventralis ) and tested by Gram's stain cytology and bacterial culture. Most bacteria (97.2%) identified by Gram's stain were gram positive. However, gram-negative organisms were identified in 7 of 21 (33.3%; 95% confidence interval: 13.3%-53.3%) birds. Escherichia coli was the only gram-negative organism identified on culture. Agreement between results of Gram's stain and culture was fair (weighted κ = 0.27). The results of this study suggest that Gram's stains and bacterial culture may need to be performed with a parallel testing strategy to limit the likelihood of misclassifying the microbial flora of psittacine patients.

Non-contiguous finished genome sequence and description of Brevibacterium senegalense sp. nov

Brevibacterium senegalense strain JC43^T sp. nov. is the type strain of Brevibacterium senegalense sp. nov., a new species within the Brevibacterium genus. This strain, whose genome is described here, was isolated from the fecal flora of a healthy Senegalese patient. B. senegalense is an aerobic rod-shaped Gram-positive bacterium. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 3,425,960 bp long genome (1 chromosome but no plasmid) contains 3,064 protein-coding and 49 RNA genes.

Native aortic valve endocarditis caused by Brevibacterium epidermidis in an immunocompetent patient

Although Brevibacterium species used to be considered as nonpathogenic microorganisms until recently, it seems that they can cause a wide variety of clinical diseases by acting mostly as opportunistic pathogens. The present case is the second reported case of infective endocarditis by Brevibacterium species; however, it is the first reported infected native aortic valve in an immunocompetent patient.

Molecular identification and differentiation of Brevibacterium species and strains

Amplified ribosomal DNA restriction enzyme analysis (ARDRA), pulsed field gel electrophoresis (PFGE) and ribotyping were used to differentiate among 24 strains of Brevibacterium linens, Brevibacterium casei and Brevibacterium epidermidis obtained from type culture collections or isolated from various smear ripened cheeses. ARDRA was applied to the 16S rDNA. B. linens was shown to be a quite heterogenic group with 2 to at least 4 copies of rrn operons per strain with aberrant nucleotide sequences. AccI gave genus specific restriction patterns and was used to separate Brevibacterium from Corynebacterium species. The expected species specificity of TaqI applied to B. linens type culture strains, but not to all strains isolated from cheese. By AvaI restriction, B. casei and B. linens were differentiated from B. epidermidis and the orange pigmented Arthrobacter casei, a new species of coryneform bacteria; by XmnI restriction, B. linens and B. epidermidis were differentiated from B. casei. One of 4 B. linens genotypes could not be distinguished from B. casei by this method. Here, the typical orange B. linens pigments were used for classification, which was confirmed by partial sequencing of the 16S rDNA.