Gram-positive Coccobacillus Research Articles

Infective Endocarditis by Listeria Species—A Systematic Review

Infective endocarditis (IE) is a disease associated with significant morbidity and mortality. It is more commonly caused by Gram-positive cocci, but Gram-positive bacilli may seldom cause the disease. Listeria monocytogenes is an aerobic Gram-positive coccobacillus and a foodborne and opportunistic pathogen most commonly causing gastrointestinal infections, even though bacteremia, sepsis, meningitis, and fetal infections may also occur. Listeria IE has rarely been described, with most reports being case reports or case series. Thus, the characteristics of this disease remain largely unknown. This systematic review aimed to present all published Listeria IE studies and describe their characteristics. A search of PubMed, Scopus, and the Cochrane Library for studies providing information on epidemiology, clinical findings, treatment, and outcome of Listeria IE cases was performed. A total of 54 studies containing data from 62 patients were included. Among all patients, 64.5% were male; the median age was 69 years. Among all patients, 54.8% had a history of a prosthetic valve. The aortic valve was the most commonly affected, followed by the mitral. Fever, heart failure, and embolic phenomena were the most commonly encountered clinical findings. The only isolated species was L. monocytogenes. Antimicrobial resistance was relatively low for aminopenicillins and aminoglycosides, the most commonly used antimicrobials for treating L. monocytogenes IE. Surgery was performed in 27.4% of patients. Mortality was 37.1%. Patients who survived were more likely to have had a prosthetic valve, to have necessitated transesophageal echocardiography for the diagnosis, to have mitral valve IE, and to have had surgical management; however, no factor was identified in a multivariate logistic regression model as an independent factor for overall mortality.

Methanobrevibacter massiliense and Pyramidobacter piscolens Co-Culture Illustrates Transkingdom Symbiosis.

Among oral microbiota methanogens, Methanobrevibacter massiliense (M. massiliense) has remained less studied than the well-characterised and cultivated methanogens Methanobrevibacter oralis and Methanobrevibacter smithii. M. massiliense has been associated with different oral pathologies and was co-isolated with the Synergistetes bacterium Pyramidobacter piscolens (P. piscolens) in one case of severe periodontitis. Here, reporting on two additional necrotic pulp cases yielded the opportunity to characterise two co-cultivated M. massiliense isolates, both with P. piscolens, as non-motile, 1-2-µm-long and 0.6-0.8-µm-wide Gram-positive coccobacilli which were autofluorescent at 420 nm. The two whole genome sequences featured a 31.3% GC content, gapless 1,834,388-base-pair chromosome exhibiting an 85.9% coding ratio, encoding a formate dehydrogenase promoting M. massiliense growth without hydrogen in GG medium. These data pave the way to understanding a symbiotic, transkingdom association with P. piscolens and its role in oral pathologies.

Rhodococcus equi-Derived Extracellular Vesicles Promoting Inflammatory Response in Macrophage through TLR2-NF-κB/MAPK Pathways.

Rhodococcus equi (R. equi) is a Gram-positive coccobacillus that causes pneumonia in foals of less than 3 months, which have the ability of replication in macrophages. The ability of R. equi persist in macrophages is dependent on the virulence plasmid pVAPA. Gram-positive extracellular vesicles (EVs) carry a variety of virulence factors and play an important role in pathogenic infection. There are few studies on R. equi-derived EVs (R. equi-EVs), and little knowledge regarding the mechanisms of how R. equi-EVs communicate with the host cell. In this study, we examine the properties of EVs produced by the virulence strain R. equi 103+ (103+-EVs) and avirulenct strain R. equi 103− (103−-EVs). We observed that 103+-EVs and 103−-EVs are similar to other Gram-positive extracellular vesicles, which range from 40 to 260 nm in diameter. The 103+-EVs or 103−-EVs could be taken up by mouse macrophage J774A.1 and cause macrophage cytotoxicity. Incubation of 103+-EVs or 103−-EVs with J774A.1 cells would result in increased expression levels of IL-1β, IL-6, and TNF-α. Moreover, the expression of TLR2, p-NF-κB, p-p38, and p-ERK were significantly increased in J774A.1 cells stimulated with R. equi-EVs. In addition, we presented that the level of inflammatory factors and expression of TLR2, p-NF-κB, p-p38, and p-ERK in J774A.1 cells showed a significant decreased when incubation with proteinase K pretreated-R. equi-EVs. Overall, our data indicate that R. equi-derived EVs are capable of mediating inflammatory responses in macrophages via TLR2-NF-κB/MAPK pathways, and R. equi-EVs proteins were responsible for TLR2-NF-κB/MAPK mediated inflammatory responses in macrophage. Our study is the first to reveal potential roles for R. equi-EVs in immune response in R. equi-host interactions and to compare the differences in macrophage inflammatory responses mediated by EVs derived from virulent strain R. equi and avirulent strain R. equi. The results of this study have improved our knowledge of the pathogenicity of R. equi.

Septicaemic Listeriosis in a White-Faced Saki (Pithecia pithecia)

A 27-year-old female white-faced saki (Pithecia pithecia) died following an onset of vomiting and ptyalism. Necropsy revealed lesions of suppurative ventriculitis, choroid plexitis, periventricular encephalitis and meningitis with intralesional gram-positive coccobacilli and paired rods. The saki also had suppurative to mononuclear hepatitis, mild intestinal crypt necrosis, proliferative glomerulonephritis, aortic arteriosclerosis, pulmonary interstitial fibrosis, chronic mild epicarditis, ovarian medullary arteriopathy and a focal superficial cerebral fibrotic nodule with surrounding chronic mixed cell inflammation. Listeria monocytogenes was cultured from liver and spinal cord. Intralesional Listeria bacteria were immunolabelled in brain sections and real-time polymerase chain reaction of brain tissue detected L. monocytogenes. Whole genome multilocus sequence typing characterized the cultured bacterial isolates as sequence type 6 and clonal complex 6. A database search for related clinical and food listerial outbreaks identified genetically related isolates but, because these isolates were more than 20 alleles distant from the saki isolates, they were not a related cluster. Reports of listeriosis in non-human primates are infrequent, and when infections do occur, they tend to be haematogenous with the propensity to cause meningoencephalitis. This saki likely ingested environmental L. monocytogenes, which resulted in disease that may have been facilitated by pre-existing co-morbidities and age.

Placentitis and abortion in domestic pigs (Sus scrofa domesticus) associated with Trueperella abortisuis on US swine farms

We document a case series of abortions and placentitis in domestic pigs from the Midwest United States where aerobic bacterial cultures consistently isolated Trueperella abortisuis. Cases were submitted between 2017-2020 to the Kansas State Veterinary Diagnostic Lab. Microscopically, there was suppurative placentitis with necrosis and intralesional, gram-positive coccobacilli. In all cases, molecular diagnostics were negative for major causes of abortion in pigs. This is the first known report of T abortisuis isolated from swine abortions or placentitis in the United States.

Intraventricular Catheter-Associated Rothia mucilaginosa Bacteremia in a Neutropenic Patient

Abstract Rothia mucilaginosa is a pleomorphic gram-positive coccobacilli found commensally in the nose and throat. Over the past several decades, it has been recognized as a rare cause of severely invasive disease in the immunocompromised. We present an uncommon case of neutropenic fever caused by R. mucilaginosa bacteremia with a recently placed Ommaya reservoir intraventricular catheter system as a potential nidus. The patient recovered after antibiotic and tbo-filgrastim therapy, as well as removal of the catheter.

Early-onset Trueperella bernardiae bacteremia in a preterm neonate

Trueperella bernardiae is a Gram-positive coccobacilli and is a commensal on human skin. It is an opportunistic pathogen and has been known to cause infections in human beings ranging from mild septicemia to brain abscess in adult population. This pathogenic organism is unheard of in neonatal population. We report a case of early-onset T. bernardiae bacteremia in a preterm neonate who was treated successfully with ampicillin and gentamicin. This is the first case report of T. bernardiae infection in neonates. This case illustrates a rare cause of early-onset sepsis in neonates.

Sellimonas caecigallum sp. nov., description and genome sequence of a new member of the Sellimonas genus isolated from the cecum of feral chicken.

An obligately anaerobic, non-motile, Gram-positive coccobacillus strain SW451 was isolated from pooled caecum contents of feral chickens. Based on taxono-genomic, and biochemical analyses, the strain SW451 represents a new species of the genus Sellimonas, for which the name Sellimonas caecigallum sp. nov. is proposed. The type strain of Sellimonas caecigallum is SW451 (=DSM 109473T = CCOS 1879T).

1342 A Rare Presentation of Lactobacillus Paracasei Endocarditis With Involvement of Aortic Prosthetic Valve in a Patient With Septic Shock Due to Acute Cholecystitis

INTRODUCTION: Endocarditis caused by Lactobacilli species is rare and usually manifests in patients with severe comorbidities, congenital heart disease, or prosthetic valves. Lactobacilli species are gram-positive coccobacilli mostly found in the gastrointestinal tract flora. Current literature shows an association of this bacterium with the use of probiotics. We hypothesize a possible association between acute cholecystitis and the occurrence of Lactobacillus endocarditis in a patient with no history of use of probiotics. CASE DESCRIPTION/METHODS: A 75-year-old female with a history of Birt-Hogg-Dube Syndrome with multiple spontaneous pneumothoraxes, COPD, aortic stenosis status post prosthetic aortic valve (AV) replacement, presented with acute respiratory failure and septic shock. She was diagnosed with acute cholecystitis, severe aortic regurgitation, and found to have lactobacillus bacteremia. We started her on empiric antibiotic coverage and later switched to penicillin G and gentamicin following three positive blood cultures for Lactobacillus paracasei. A transesophageal echocardiogram showed vegetation with emerging severe aortic regurgitation, degeneration, and perforation of AV leaflet when compared with echocardiogram one year ago. A CT-thorax demonstrated pan lobular emphysema with large cysts and pneumatoceles at the lung bases. Bacteremia persisted for two weeks after initiation of antibiotic therapy. Treatment with penicillin G and gentamicin was deemed necessary for up to 4 weeks after definitive surgical treatment. However, the patient's severe lung condition complicated preoperative clearance, and she was transferred to a specialized center for open-heart AV replacement. DISCUSSION: Very few cases of Lactobacillus endocarditis are reported in the literature. A handful of studies describe some implicated pathogenesis of the Lactobacillus in the blood as induced by cholecystitis. Other studies suggest that the increased presence of Lactobacillus in the respiratory tract in cases of severe lung pathology can lead to hematogenous dissemination to the heart valves. However, the association between Lactobacillus species and prosthetic valve material (and implication with endocarditis) is currently well-established. All things considered, and despite the lack of histopathology, we suggest that the source of Lactobacillus was likely the acute cholecystitis, and the presence of lung comorbidities and prosthetic AV further exacerbated the patient's condition.

Treatment and prevention of Rhodococcus equi in foals.

Rhodococcus equi is an intracellular, facultative, Gram-positive coccobacillus that is ubiquitous in soil. It is also one of the most common causes of pneumonia in foals and has a major financial impact on the horse industry worldwide due to its high morbidity and mortality and the costs associated with treatment.1,2 Epidemiological evidence suggests that foals become infected early in life, and it is generally accepted that infection is established through the inhalation of airborne dust containing R equi .3,4 Foals exhibiting clinical signs are thought to be the main source of R equi in the environment as they shed higher concentrations of R equi in their faeces than subclinically infected foals or infected adult horses.5 It is known that indoor housing of foals significantly increases the risk of R equi infection compared with outdoor housing due to the higher concentrations of airborne particles present.6–8 However, our understanding of the risk factors for the development of R equi pneumonia is limited. On many farms, thoracic ultrasonography is used to screen foals for the early stages of R equi …

Bacteremia caused by <italic>Leuconostoc</italic> species : 6-case series

Leuconostoc species are Gram-positive coccobacilli and are used in dairy products and are intrinsically resistant to vancomycin. Leuconostoc infections are rare in humans, usually occurring in immune-compromised patients. We describe 6 patients with Leuconostoc bacteremia at Dong-A university hospital between 1990 and 2015. One isolate ( L. lactis ) was identified to species level using 16S rRNA gene sequencing analysis. All patients had underlying diseases and 5 patients underwent procedures that interrupted the normal integumentary defense. Four patients died within 30 days after being identified as carrying Leuconostoc species.

Rhodococcus equi Pneumonia in Kidney Transplant Recipient Affected by Acute Intermittent Porphyria: A Case Report

Rhodococcus equi is a gram-positive coccobacillus responsible for severe infections in patients with weakened immune systems. R equi generally causes pnumonia that may evolve into fatal systemic infection if left untreated. Here, we present a case of a 67-year-old woman affected by acute intermittent porphyria (AIP) who developed R equi pneumonia 7 months after kidney transplantation. Although clinical features at presentation were nonspecific, lung computed tomography showed right perihilar consolidation with a mass-like appearance causing bronchial obstruction. Appropriate antibiotic including intravenous meropenem and oral azithromycin that was then switched to oral levofloxacin and oral azithromycin along with reduction of immunosuppressive therapy resolved pneumonia without provoking an acute attack of porphyria. AIP limited the choice of antibiotics for the treatment of R equi infection because some potentially porphyrinogenic antibacterial agents were avoided. Based on this experience, azithromycin and meropenem can be safely administered for the treatment of R Equi infection in patients with AIP.

Rothia mucilaginosa Bacteremia and Subsequent Typhlitis in a Patient With Acute Myeloid Leukemia

Abstract Rothia mucilaginosa is a gram-positive coccobacilli that is part of the normal flora of the human oropharynx and upper respiratory tract. Rothia spp. cause a wide range of serious infections, especially in immunocompromised hosts. We report a 54-year-old man with acute myelogenous leukemia, who recently had gingivitis and tooth extraction in preparation for bone marrow transplant evaluation. After receiving induction chemotherapy with cladribine, cytarabine, filgrastim, and mitoxantrone, he developed an upper gingival ulceration and subsequent Rothia mucilaginosa bacteremia on day 15 of hospitalization. He remained neutropenic on broad-spectrum antimicrobials and had intermittent breakthrough fevers. On day 17, he developed abdominal pain and was subsequently diagnosed with neutropenic enterocolitis. Despite broad-spectrum antibiotics, he died with sepsis and multiorgan failure.

Malacoplaquia pulmonar y abdominal en un paciente VIH positivo. Reporte preliminar

Pulmonary malakoplakia associated with Rhodococcus equi is unusual. Herein we describe a 19-year-old man infected with the human immunodeficiency virus complaining of fever and cough. The computerized tomography scan revealed a mediastinal and right pulmonary tumor mass with multiples abdominal lymph nodes enlargements. Histologic examination of a bronchial biopsy specimen revealed sheets of histiocytic cells that contained coccobacillary organisms and «target-like» cytoplasmic inclusions corresponding with Michaelis-Gutmann bodies. Cultures of the lung tissue yielded growth of gram-positive coccobacilli subsequently identified as Rhodococcus equi. The intraabdominal biopsy reveals areas with similar histopathology of lung lesion. In immunocompromised patients, the possibility of malakoplakia should be considered in the differential diagnosis of pulmonary and/or systemic lesions composed of histiocytic cells.

Identification and significance of Weissella species infections.

Weissella spp. are non-spore forming, catalase-negative, gram-positive coccobacilli. They are often misidentified by traditional and commercial phenotypic identification methods as Lactobacillus spp. or Lactobacillus-like organisms. Weissella spp. were previously grouped along with Lactobacillus spp., Leuconostoc spp., and Pediococcus spp. Utilization of more sensitive methods like DNA sequencing or Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) has facilitated identification of Weissella as a unique genus. Nineteen species have been identified to date. W. confusa, W. cibaria, and W. viridescens are the only species isolated from humans. The true prevalence of Weissella spp. continues to be probably underestimated. Weissella spp. strains have been isolated from a wide range of habitats including raw milk, feces, fermented cereals, and vegetables. Weisella is believed to be a rare cause of usually nonfatal infections in humans, and is often considered a contaminant. However, in recent years, Weissella spp. have been implicated in bacteremia, abscesses, prosthetic joint infections, and infective endocarditis. Alterations of the gut flora from surgery or chemotherapy are believed to facilitate translocation of Weissella spp. due to disruption of the mucosal barrier, predisposing the host to infection with this organism. Implications of the isolation of Weissella spp. from blood must be interpreted in context of underlying risk factors. Weissella spp. are inherently resistant to vancomycin. Therefore, early consideraton of the pathogenic role of this bacteria and choice of alternate therapy is important to assure better outcomes.

Isolation and Characterization of Tannin-Degrading Bacteria from the Rumen of Goats Fed Oak (Quercus semicarpifolia) Leaves

Tannin-degrading bacteria (TDGB) were isolated from the rumen of goats fed oak leaves containing diet. The isolates were screened for their ability to increase in vitro digestibility of oak leaves (Quercus semicarpifolia), and fifteen best isolates were selected for further characterisation. The isolates TDGB 19, 20, 406, 415, 417, 420, 425, 437, 446, and 450 were Gram-positive cocci with medium- and long-chains, and isolates TDGB 409, 428, 430, and 433 were Gram-positive cocco-bacilli of short chain length. All the isolates exhibited tannase activity with the maximum in TDGB 417 (72.0 units; nmol methyl gallate degraded/min/ml) and minimum in TDGB 433 (28.92 units). All the fifteen isolates utilized fructose, galactose, lactose, starch, maltose, glycerol, and mannose as carbon source. The isolates were tested for their tolerance to phenolic monomers like ferulic acid, vanillic acid, coumaric acid, pyrogallol acid, and gallic acid. All the isolates could tolerate the presence of pyrogallol and gallic acid up to 20 mM, but ferulic was toxic at 20 mM level for all the isolates. The isolates were able to degrade tannic acid to pyrogallol except isolates TDGB 409, 428, 430, and 433, which could degrade tannic acid only up to gallic acid after 24 h of incubation as assessed by thin-layer chromatography. None of the isolates degraded tannic acid to resorcinol even after 96 h of incubation. The phylogenetic analysis of the isolates using sequences of PCR amplicons generated by the three sets of primers, two primers sets targeting 16S rRNA gene and one targeting sodA gene for superoxide dismutase enzyme, revealed that the isolates TDGB 7, 19, 20, 406, 417, 446, and 450 formed a close cluster with Streptococcus gallolyticus with 99 to 100 % similarity in all the three phylogenetic trees. There was a maximum of 11 % improvement in vitro true degradability of tannin-rich feed in the presence of live culture of TDGB 406 and can be exploited as a probiotic to improve nutrient utilization of tannin-containing feed given to the livestock.

Rothia bacteremia: a 10-year experience at Mayo Clinic, Rochester, Minnesota.

Rothia spp. are Gram-positive cocco-bacilli that cause a wide range of serious infections, especially in immunocompromised hosts. Risk factors for Rothia mucilaginosa (previously known as Stomatococcus mucilaginosus) bacteremia include prolonged and profound neutropenia, malignancy, and an indwelling vascular foreign body. Here, we describe 67 adults at the Mayo Clinic in Rochester, MN, from 2002 to 2012 with blood cultures positive for Rothia. Twenty-five of these patients had multiple positive blood cultures, indicating true clinical infection. Among these, 88% (22/25) were neutropenic, and 76% (19/25) had leukemia. Common sources of bacteremia were presumed gut translocation, mucositis, and catheter-related infection. One patient died with Rothia infection. Neutropenic patients were less likely to have a single positive blood culture than were nonneutropenic patients. Antimicrobial susceptibility testing was performed on 21% of the isolates. All of the tested isolates were susceptible to vancomycin and most beta-lactams; however, four of six tested isolates were resistant to oxacillin. There was no difference between the neutropenic and nonneutropenic patients in need of intensive care unit care, mortality, or attributable mortality.

제주지역 흑염소에서 뇌염형 리스테리아증 발생 증례 보고

In February 2013, two Korean native goats with circling, dysphagia, sialorrhea, and death were submitted for necropsy to the Jeju Self-Governing Provincial Veterinary Research Institute. Histopathologically, multifocal to confluent micro-abscess composed of neutrophils and macrophages and severe multifocal perivascular cuffing were observed in pons, medulla oblongata, and cerebellum. Isolated bacteria from the brain sample were Gram-positive coccobacilli and were confirmed as Listeria (L.) monocytogenes by VITEK and PCR analysis. Based on clinical sign, histopathology and bacterial isolation, this case was diagnosed as encephalitic listeriosis. In our best knowledge, this is the first report of encephalitic listeriosis caused by L. monocytogenes in Korean native goats in Jeju.

The First Case of Eggerthella lenta Bacteremia in Korea

The First Case of <i>Eggerthella lenta</i> Bacteremia in Korea

Weissella confusa septicemia in a foal

Weissella confusa is a Gram-positive bacterium that has been identified in environmental and food samples from around the world. Rare cases of bacteremia in immunocompromised people have been reported. A 2-day-old foal was presented for weakness and suspected sepsis. Blood culture yielded pure growth of a Gram-positive coccobacillus, which was identified as W. confusa through sequencing of the 16S ribosomal DNA. Although the foal initially responded to antimicrobial therapy with ceftiofur and metronidazole, it later developed septic complications of the right tarsocrural joint and right digital flexor tendon sheath and was euthanized. Postmortem examination and histology revealed subcutaneous icterus, severe diffuse interstitial pneumonia, septic synovitis, necrotizing vasculitis with marked thrombosis and hemorrhage in the medial digital vessels of the right hind limb, and ischemic necrosis of the right hind hoof laminae. Gram-positive, coccobacilli were observed in the vascular lesion.