Cardiobacterium valvarum | |
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Species: | C. valavarum |
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Cardiobacterium valvarum | |
Cardiobacterium valvarum is a Gram-negative species of bacteria belonging to the Cardiobacterium genus. It belongs to the HACEK group of fastidious bacteria that are present in normal oropharyngeal flora and can develop into infective endocarditis.
The only other identified Cardiobacterium species is Cardiobacterium hominis . Cardiobacterium species are Gram-negative, pleomorphic rod-shaped bacteria that are catalase-negative and oxidase-positive. When compared morphologically, the two Cardiobacterium species are indistinguishable in culture and Gram stain, however the two differ in growth patterns: C. valvarum is more fastidious than C. hominis, and is non-hemolytic. C. valvarum is also differentiated by the fact that the species does not produce indole. [1]
Isolates of C. valvarum show optimal growth by day 3 under standard 5% CO2 incubation conditions on 5% sheep blood, but scant growth on chocolate agar.
Members of the HACEK group are difficult to identify through conventional methods. 16S ribosomal RNA genotyping is the necessary method of identifying C.valvarum [2] . C.valvarum bears numerous phenotypic similarities with Pasteurella multocida and is therefore commonly misidentified. The phenylphosphonate reaction and Maldi-TOF mass spectrometry can be used to distinguish the two species.
The Cardiobacterium species are broadly susceptible to beta-lactam, trimethoprim-sulfamethoxazole, fluoroquinolones, and aztreonam. Current clinical guidelines recommend that C. valvarum infection be treated with a 4-week course of ceftriaxone or ciprofloxacin. [3]
Bloodstream infections (BSIs), septicemia which include bacteremias when the infections are bacterial and fungemias when the infections are fungal, are infections present in the blood. Blood is normally a sterile environment, so the detection of microbes in the blood is always abnormal. A bloodstream infection is different from sepsis, which is the host response to bacteria.
The HACEK organisms are a group of fastidious Gram-negative bacteria that are an unusual cause of infective endocarditis, which is an inflammation of the heart due to bacterial infection. HACEK is an abbreviation of the initials of the genera of this group of bacteria: Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella. The HACEK organisms are a normal part of the human microbiota, living in the oral-pharyngeal region.
Infective endocarditis is an infection of the inner surface of the heart, usually the valves. Signs and symptoms may include fever, small areas of bleeding into the skin, heart murmur, feeling tired, and low red blood cell count. Complications may include backward blood flow in the heart, heart failure – the heart struggling to pump a sufficient amount of blood to meet the body's needs, abnormal electrical conduction in the heart, stroke, and kidney failure.
Acinetobacter is a genus of Gram-negative bacteria belonging to the wider class of Gammaproteobacteria. Acinetobacter species are oxidase-negative, exhibit twitching motility, and occur in pairs under magnification.
The viridans streptococci are a large group of commensal streptococcal Gram-positive bacteria species that are α-hemolytic, producing a green coloration on blood agar plates, although some species in this group are actually γ-hemolytic, meaning they produce no change on blood agar. The pseudo-taxonomic term "Streptococcus viridans" is often used to refer to this group of species, but writers who do not like to use the pseudotaxonomic term prefer the terms viridans streptococci, viridans group streptococci (VGS), or viridans streptococcal species.
A blood culture is a medical laboratory test used to detect bacteria or fungi in a person's blood. Under normal conditions, the blood does not contain microorganisms: their presence can indicate a bloodstream infection such as bacteremia or fungemia, which in severe cases may result in sepsis. By culturing the blood, microbes can be identified and tested for resistance to antimicrobial drugs, which allows clinicians to provide an effective treatment.
Coliform bacteria are defined as either motile or non-motile Gram-negative non-spore forming Bacilli that possess β-galactosidase to produce acids and gases under their optimal growth temperature of 35-37°C. They can be aerobes or facultative aerobes, and are a commonly used indicator of low sanitary quality of foods, milk, and water. Coliforms can be found in the aquatic environment, in soil and on vegetation; they are universally present in large numbers in the feces of warm-blooded animals as they are known to inhabit the gastrointestinal system. While coliform bacteria are not normally causes of serious illness, they are easy to culture, and their presence is used to infer that other pathogenic organisms of fecal origin may be present in a sample, or that said sample is not safe to consume. Such pathogens include disease-causing bacteria, viruses, or protozoa and many multicellular parasites.
The Gimenez staining technique uses biological stains to detect and identify bacterial infections in tissue samples. Although largely superseded by techniques like Giemsa staining, the Gimenez technique may be valuable for detecting certain slow-growing or fastidious bacteria.
Staphylococcus warneri is a member of the bacterial genus Staphylococcus, consisting of Gram-positive bacteria with spherical cells appearing in clusters. It is catalase-positive, oxidase-negative, and coagulase-negative, and is a common commensal organism found as part of the skin flora on humans and animals. Like other coagulase-negative staphylococci, S. warneri rarely causes disease, but may occasionally cause infection in patients whose immune system is compromised.
Burkholderia cepacia complex (BCC), or simply Burkholderia cepacia, is a group of catalase-producing, lactose-nonfermenting, Gram-negative bacteria composed of at least 20 different species, including B. cepacia, B. multivorans, B. cenocepacia, B. vietnamiensis, B. stabilis, B. ambifaria, B. dolosa, B. anthina, B. pyrrocinia and B. ubonensis. B. cepacia is an opportunistic human pathogen that most often causes pneumonia in immunocompromised individuals with underlying lung disease. Patients with sickle-cell haemoglobinopathies are also at risk. The species complex also attacks young onion and tobacco plants, and displays a remarkable ability to digest oil. Burkholderia cepacia is also found in marine environments and some strains of Burkholderia cepacia can tolerate high salinity. S.I. Paul et al. (2021) isolated and biochemically characterized salt tolerant strains of Burkholderia cepacia from marine sponges of Saint Martin's Island of the Bay of Bengal, Bangladesh.
Eikenella corrodens is a Gram-negative facultative anaerobic bacillus that can cause severe invasive disease in humans. It was first identified by M. Eiken in 1958, who called it Bacteroides corrodens. E. corrodens is a rare pericarditis associated pathogen. It is a fastidious, slow growing, human commensal bacillus, capable of acting as an opportunistic pathogen and causing abscesses in several anatomical sites, including the liver, lung, spleen, and submandibular region. E. corrodens could independently cause serious infection in both immunocompetent and immunocompromised hosts.
Capnocytophaga canimorsus is a fastidious, slow-growing, Gram-negative rod of the genus Capnocytophaga. It is a commensal bacterium in the normal gingival flora of canine and feline species, but can cause illness in humans. Transmission may occur through bites, licks, or even close proximity with animals. C. canimorsus generally has low virulence in healthy individuals, but has been observed to cause severe, even grave, illness in persons with pre-existing conditions. The pathogenesis of C. canimorsus is still largely unknown, but increased clinical diagnoses have fostered an interest in the bacillus. Treatment with antibiotics is effective in most cases, but the most important yet basic diagnostic tool available to clinicians remains the knowledge of recent exposure to canines or felines.
Spirillum minus is an organism associated with rat-bite fever that has never been fully identified and was assigned to the genus Spirillum in 1887 based on morphology, although it is not a validly published name. As Spirillum species generally obligately microaerophiles and are not found in mammals, this organism may be misclassified. Sequencing data should help to resolve this question.
Actinobacillus is a genus of Gram-negative, nonmotile and non-spore-forming, oval to rod-shaped bacteria occurring as parasites or pathogens in mammals, birds, and reptiles. It is a member of the family Pasteurellaceae. The bacteria are facultatively anaerobic or aerobic, capable of fermenting carbohydrates, and of reducing nitrates. The genomic DNA contains between 40 and 47 mol % guanine plus cytosine.
Kingella kingae is a species of Gram-negative facultative anaerobic β-hemolytic coccobacilli. First isolated in 1960 by Elizabeth O. King, it was not recognized as a significant cause of infection in young children until the 1990s, when culture techniques had improved enough for it to be recognized. It is best known as a cause of septic arthritis, osteomyelitis, spondylodiscitis, bacteraemia, and endocarditis, and less frequently lower respiratory tract infections and meningitis.
Kingella is a genus of bacteria of the family Neisseriaceae. It belongs to the HACEK group of fastidious Gram-negative bacteria that tend to cause endocarditis. Kingella kingae is its type species.
Cardiobacterium hominis is a Gram-negative bacillus (rod-shaped) bacterium commonly grouped with other bacteria into the HACEK group. It is one of several bacteria that is normally present in the mouth and upper part of the respiratory tract such as nose and throat. However, it may also rarely cause endocarditis, an infection of the heart valves.
Cardiobacterium is a Gram-negative bacillus (rod-shaped) bacterium commonly grouped with other bacteria into the HACEK group. Species of Cardiobacterium include Cardiobacterium hominis and Cardiobacterium valvarum.
C. hominis may refer to:
In microbiology, Suttonella indologenes, formerly Kingella indologenes, is a Gram-negative rod-shaped bacterium of the family Cardiobacteriaceae. Like other members of its family, it is a bacterium that is assumed to be normally present in the respiratory tract. It has been found to rarely cause endocarditis, an infection of the heart valves. It also been found in the eye. It may cause eye infections. Little is known about it as a bacterium other than its structure and biochemical composition. Like other members in its family, it has a characteristic 16S ribosomal RNA which consists of 1474 base pairs.