Eikenella | |
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Eikenella corrodens on chocolate agar after 36 hours. Notice how colonies pit the agar, which is a distinct characteristic of this species. | |
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Species: | E. corrodens |
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Eikenella corrodens (Eiken 1958) Jackson and Goodman 1972 (Approved Lists 1980) | |
Eikenella corrodens is a Gram-negative facultative anaerobic bacillus that can cause severe invasive disease in humans. [1] It was first identified by M. Eiken in 1958, who called it Bacteroides corrodens. [2] E. corrodens is a rare pericarditis associated pathogen. [3] 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. [4] E. corrodens could independently cause serious infection in both immunocompetent and immunocompromised hosts. [5]
Eikenella corrodens is a pleomorphic bacillus that sometimes appears coccobacillary and typically creates a depression (or "pit") in the agar on which it is growing. Only half produce the pitting of the agar considered characteristic.[ citation needed ]. It is a slow-growing, facultative anaerobe and a gram-negative bacillus. [6]
It grows in aerobic and anaerobic conditions, but requires an atmosphere enhanced by 3–10% carbon dioxide.[ citation needed ]
The colonies are small and greyish, they produce a greenish discoloration of the underlying agar, and smell faintly of bleach (hypochlorite).[ citation needed ]
They are oxidase-positive, catalase-negative, urease-negative, and indole-negative, and reduce nitrate to nitrite.[ citation needed ]
In 2006, Azakami et al reported that the periodontal pathogen E. corrodens has an ortholog of luxS , the gene required for quorum sensing (QS) signal molecule AI-2 synthesis and that E. corrodens can produce AI-2 signals for cell-to-cell communication. They additionally reported that AI-2 has a role in biofilm formation by E. corrodens. [7] Karim et al reported that this bacterium can produce AI-2 inactivation enzyme during its stationary phase. [8] Karim et al also reported that LuxS-mediated QS may facilitate the maturation and detachment of biofilm formation in E. corrodens, which can lead to progression of periodontal disease. [9]
Eikenella corrodens is a commensal of the human mouth and upper respiratory tract. It is an unusual cause of infection and when it is cultured, it is most usually found mixed with other organisms. Infections most commonly occur in patients with cancers of the head and neck, [10] but can occur in human bite infections, especially "reverse bite", "fight bite", or "clenched fist injuries". [11] It can also cause infections in insulin-dependent diabetics and intravenous drug users who lick their needles ("needle-licker's osteomyelitis"). [12] It is one of the HACEK group of infections which are a cause of culture-negative endocarditis. In general, the HACEK organisms are responsible for approximately 3% of all cases of infective endocarditis (IE). IE due to E. corrodens is usually a result of poor oral hygiene and or periodontal infection. Manipulation of the gingival or oral mucosa for dental procedures also can predispose patients to infection since E. corrodens is a constituent of the human oral flora. [13] E. corrodens can coexists and is frequently detected with other pathogens including Staphylococcus and Streptococcus. [14]
Eikenella corrodens infections are typically indolent (the infection does not become clinically evident until a week or more after the injury). They also mimic anaerobic infection in being extremely foul-smelling.[ citation needed ]
Eikenella corrodens was mentioned in an episode of Forensic Files , in which a hotel employee punched a woman in the mouth, knocking out two of her teeth. Her tooth bacteria caused a major infection in the man's hand.[ citation needed ]
For accurate diagnoses, a high degree of suspicion is required in order to properly attribute an infection to Eikenella corrodens. [15] The identification of E. corrodens may be delayed because of its slow growth in the absence of CO2. [16] E. corrodens can be treated with penicillins, cephalosporins, or tetracyclines, however due to the resistant nature of the bacteria ongoing and recurring symptoms can be expected despite rigorous and prolonged antibiotic treatment. [17] Submandibular and peritonsillar abscesses caused by E. corrodens can be treated by incision and drainage. [18] Earlier diagnosis and proper drainage surgery with effective antibiotics treatment may improve the prognosis. [19] First-choice drugs for E. corrodens infections should be third-generation cephems, carbapenems, or new quinolones. [20] It is innately resistant to macrolides (e.g., erythromycin), clindamycin, and metronidazole. It is susceptible to fluoroquinolones (e.g., ciprofloxacin) in vitro, but no clinical evidence is available to advocate their use in these infections. [21]
An abscess is a collection of pus that has built up within the tissue of the body. Signs and symptoms of abscesses include redness, pain, warmth, and swelling. The swelling may feel fluid-filled when pressed. The area of redness often extends beyond the swelling. Carbuncles and boils are types of abscess that often involve hair follicles, with carbuncles being larger. A cyst is related to an abscess, but it contains a material other than pus, and a cyst has a clearly defined wall.
Streptococcal pharyngitis, also known as streptococcal sore throat, is pharyngitis caused by Streptococcus pyogenes, a gram-positive, group A streptococcus. Common symptoms include fever, sore throat, red tonsils, and enlarged lymph nodes in the front of the neck. A headache and nausea or vomiting may also occur. Some develop a sandpaper-like rash which is known as scarlet fever. Symptoms typically begin one to three days after exposure and last seven to ten days.
Lemierre's syndrome is infectious thrombophlebitis of the internal jugular vein. It most often develops as a complication of a bacterial sore throat infection in young, otherwise healthy adults. The thrombophlebitis is a serious condition and may lead to further systemic complications such as bacteria in the blood or septic emboli.
Fusobacterium is a genus of obligate anaerobic, Gram-negative, non-sporeforming bacteria belonging to Gracilicutes. Individual cells are slender, rod-shaped bacilli with pointed ends. Fusobacterium was discovered in 1900 by Courmont and Cade and is common in the flora of humans.
Pharyngitis is inflammation of the back of the throat, known as the pharynx. It typically results in a sore throat and fever. Other symptoms may include a runny nose, cough, headache, difficulty swallowing, swollen lymph nodes, and a hoarse voice. Symptoms usually last 3–5 days, but can be longer depending on cause. Complications can include sinusitis and acute otitis media. Pharyngitis is a type of upper respiratory tract infection.
Sputum is mucus that is coughed up from the lower airways. In medicine, sputum samples are usually used for a naked eye examination, microbiological investigation of respiratory infections and cytological investigations of respiratory systems. It is crucial that the specimen does not include any mucoid material from the nose or oral cavity.
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.
Peritonsillar abscess (PTA), also known as quinsy, is an accumulation of pus due to an infection behind the tonsil. Symptoms include fever, throat pain, trouble opening the mouth, and a change to the voice. Pain is usually worse on one side. Complications may include blockage of the airway or aspiration pneumonitis.
Sialadenitis (sialoadenitis) is inflammation of salivary glands, usually the major ones, the most common being the parotid gland, followed by submandibular and sublingual glands. It should not be confused with sialadenosis (sialosis) which is a non-inflammatory enlargement of the major salivary glands.
Fusobacterium necrophorum is a species of bacteria responsible for Lemierre's syndrome. It has also been known to cause sinusitis, mastoiditis, and odontogenic infections.
Mycobacteroides abscessus is a species of rapidly growing, multidrug-resistant, nontuberculous mycobacteria (NTM) that is a common soil and water contaminant. Although M. abscessus most commonly causes chronic lung infection and skin and soft tissue infection (SSTI), it can also cause infection in almost all human organs, mostly in patients with suppressed immune systems. Amongst NTM species responsible for disease, infection caused by M. abscessus complex are more difficult to treat due to antimicrobial drug resistance.
Ralstonia is a genus of bacteria, previously included in the genus Pseudomonas. It is named after the American bacteriologist Ericka Ralston. Ericka Ralston was born Ericka Barrett in 1944 in Saratoga, California, and died in 2015 in Sebastopol, California. While in graduate school at the University of California at Berkeley, she identified 20 strains of Pseudomonas which formed a phenotypical homologous group, and named them Pseudomonas pickettii, after M.J. Pickett in the Department of Bacteriology at the University of California at Los Angeles, from whom she had received the strains. Later, P. pickettii was transferred to the new genus Ralstonia, along with several other species. She continued her research into bacterial pathogenesis under the name of Ericka Barrett while a professor of microbiology at the University of California at Davis from 1977 until her retirement in 1996.
Cardiobacterium hominis /ˌkɑːrdiəʊbækˈtɪəriəm ˈhɒmɪnɪs/ is a microaerophilic, pleomorphic, fastidious, Gram-negative bacterium part of the Cardiobacteriaceae family and the HACEK group. It is most commonly found in the human microbiota, specifically the oropharyngeal region including the mouth and upper part of the respiratory tract. It is one of the causes of endocarditis, a life-threatening inflammation close to the heart's inner lining and valves. While infections caused by Cardiobacterium hominis are uncommon, various clinical manifestations are linked to the bacterium, including meningitis, septicemia, and bone infections.
Morganella morganii is a species of Gram-negative bacteria. It has a commensal relationship within the intestinal tracts of humans, mammals, and reptiles as normal flora. Although M. morganii has a wide distribution, it is considered an uncommon cause of community-acquired infection, and it is most often encountered in postoperative and other nosocomial infections, such as urinary tract infections.
The Streptococcus anginosus group (SAG), also known as the anginosus group streptococci (AGS) or the milleri group streptococci (MGS), are a group of several species of streptococci with clinical similarities. The group is named after a principal member species, Streptococcus anginosus. The older name Streptococcus milleri is now pseudotaxonomic, as the idea that these streptococci constituted a single species was incorrect. The anginosus group streptococci are members of the viridans streptococci group. They have been implicated as etiologic agents in a variety of serious purulent infections, but because of their heterogeneous characteristics, these organisms may be unrecognized or misidentified by clinical laboratorians. The unique characteristic of them from other pathogenic streptococci, such as S. pyogenes and S. agalactiae, is their ability to cause abscesses.
A periodontal abscess, is a localized collection of pus within the tissues of the periodontium. It is a type of dental abscess. A periodontal abscess occurs alongside a tooth, and is different from the more common periapical abscess, which represents the spread of infection from a dead tooth. To reflect this, sometimes the term "lateral (periodontal) abscess" is used. In contrast to a periapical abscess, periodontal abscesses are usually associated with a vital (living) tooth. Abscesses of the periodontium are acute bacterial infections classified primarily by location.
Periodontal pathogens are bacteria that have been shown to significantly contribute to periodontitis.
Bergeyella zoohelcum is a Gram-negative, rod-shaped, aerobic and non-motile bacterium from the genus of Bergeyella which occurs in the upper respiratory tract of dogs and cats Bergeyella zoohelcum can cause respiratory disease in cats. Bergeyella zoohelcum can cause infections after dog bites.
Antimicrobial nanotechnology is the study of using biofilms to disrupt a microbe's cell membrane, deliver an electric charge to the microbe, and cause immediate cellular death via a "mechanical kill" process, preventing the original microbe from mutating into a superbug.
Purulent pericarditis refers to localized inflammation in the setting of infection of the pericardial sac surrounding the heart. In contrast to other causes of pericarditis which may have a viral etiology, purulent pericarditis refers specifically to bacterial or fungal infection of the pericardial sac. Clinical etiologies of purulent pericarditis may include recent surgery, adjacent infection, trauma, or even primary infection. The onset of purulent pericarditis is usually acute, with most individuals presenting to a medical facility approximately 3 days following the onset of symptoms.