Polymicrobial native valve endocarditis due to Bacillus cereus and Cardiobacterium hominis.

We present a case of polymicrobial subacute bacterial endocarditis and bacteremia with Bacillus cereus and Cardiobacterium hominis in a 72-year-old man with pre-existing mitral valve disease and prior mitral valve repair who presented with renal failure and glomerulonephritis. Bacillus is often a contaminant in blood cultures but has been rarely implicated in patients with invasive infections such as endocarditis. Intravenous drug use, prosthetic heart valves, valvular heart disease and venous catheters are the most frequently described risk factors for Bacillus bacteremia and endocarditis in the medical literature. Management is challenging as Bacillus is resistant to penicillin and cephalosporin antibiotics due to production of beta-lactamase. Polymicrobial endocarditis is uncommon and when it occurs typically involves Staphylococcal species. To our knowledge, this is the first reported case of polymicrobial endocarditis in which both Bacillus and a HACEK organism are implicated.

Gram-negative endocarditis: disease presentation, diagnosis and treatment.

PURPOSE OF REVIEW: Gram-negative bacilli (GNB) cause between 1% and 10% of infective endocarditis (IE). Most episodes are caused by microorganisms of the Haemophilus spp., Aggregatibacter spp. Cardiobacterium spp., Eikenella spp., and Kingella spp (HACEK) group. The frequency of IE caused by non-HACEK (GNB-IE) has increased in recent years. Uncertainties persist regarding its best medical treatment and the appropriateness and timing of surgical treatment. In addition, there are new drugs with activity against multiresistant microorganisms, of which there is little experience in this disease. We review this topic by answering the most frequently asked questions that arise among our colleagues. RECENT FINDINGS: HACEK microorganisms cause 1.5-2% of IE with only a 2% mortality. In contrast, non-HACEK GNB-IE accounts for 2.5-3% of all IE cases and is associated with nosocomial acquisition, advanced age, solid organ transplantation and 20-30% mortality. Drug addiction is important in areas with epidemic opioid abuse. SUMMARY: The frequency of IE caused by GNB has been modified in recent years. HACEK episodes are no longer treated with ampicillin and aminoglycosides. In non-HACEK GNB-IE, combination therapy with a beta-lactam and a quinolone or aminoglycoside is recommended. The surgical indication and its value are evident in many patients. Management should rely on a collaborative group with experience in this disease.

[Relationship between oral Candida albicans and flora in children with severe early childhood caries].

PURPOSE: To investigate the relationship between oral Candida albicans and flora in children with severe infant caries. METHODS: Forty-two children with severe infant caries (experimental group) and 40 caries-free children (control group) treated in Peking University Shenzhen Hospital from March 2018 to June 2019 were enrolled. The samples of saliva and plaque were collected and cultured. According to the culture results, the experimental group was further divided into two subgroups: Candida albicans positive group and Candida albicans negative group. The samples were sequenced by high-throughput sequencing technology, then the diversity and abundance of bacteria were analyzed. The data were processed by SPSS 23.0 software package. RESULTS: The positive rates of Candida albicans in saliva and plaque were significantly higher in the experimental group than in the control group(P<0.05). The abundance of Leptotrichia and Cardiobacterium in the saliva of children with positive Candida albicans in the experimental group was significantly higher than that of children with negative Candida albicans(P<0.05). The abundance of Prevotella in plaque of children with positive Candida albicans in the experimental group was significantly higher than that of children with negative Candida albicans and control group(P<0.05). The abundance of Leptotrichia in saliva of children with positive Candida albicans in the experimental group was significantly higher than that of children with negative Candida albicans (P<0.05), while the abundances of Capnocytophaga, Cardiobacterium hominis, and Capnocytophaga granulose were significantly lower than those of children with negative Candida albicans(P<0.05). The abundance of Streptococcus mutans, Lactobacillus gasseri, and Lactobacillus vaginalis in the plaque of positive Candida albicans in the experimental group were significantly higher than those of children with negative Candida albicans(P<0.05), while the abundance of Lactobacillus plantarum was significantly lower than that of children with negative Candida albicans (P<0.05). CONCLUSIONS: Candida albicans in children with severe infant caries children is closely correlated with the abundance of Leptotrichia, Capnocytophaga, Cardiobacterium hominis, Capnocytophaga granulosa, Streptococcus mutans and Lactobacillus, which may play a synergistic or antagonistic role.

Hemolytic Anemia in a Patient with Subacute Bacterial Endocarditis by Cardiobacterium hominis.

Hemolytic anemia is a rarely occurring manifestation of native valve infective endocarditis. We herein report an afebrile patient with hemolytic anemia caused by Cardiobacterium hominis endocarditis. A 60-year-old Japanese man had a history of aortic root replacement and the gradual onset of general fatigue. He had hemolytic anemia. Blood cultures detected C. hominis. A transthoracic echocardiogram showed aortic valve vegetation and periannular abscess with perforation of the non-coronary cusp. Intravascular hemolysis recovered after antimicrobial therapy, surgical removal of the vegetation and abscess, and aortic valve replacement. Subacute endocarditis should be considered if patients develop hemolytic anemia with signs of chronic inflammation without a fever.

An unusual case of Cardiobacterium valvarum causing aortic endograft infection and osteomyelitis.

BACKGROUND: HACEK (Haemophilus spp., Aggregatibacter spp., Cardiobacterium spp., Eikenella corrodens, and Kingella spp.) group organisms are responsible for 0.8% to 6% of all infective endocarditis cases, with Cardiobacterium spp. being the third most commonly implicated HACEK microorganism. Within this genus is Cardiobacterium valvarum (C. valvarum), a novel organism described in 2004. To date, only 15 cases of C. valvarum infection have been reported in the English-language literature, and have primarily been cases of infective endocarditis in patients with valvular disease. C. valvarum has not been reported to cause infections spreading to the surrounding bone. CASE PRESENTATION: We present a case of a 57-year-old man with a history of aortic dissection followed by aortic endograft replacement who presented with back pain. He was found to have radiographic evidence of an infected aortic endograft, along with vertebral osteomyelitis, discitis, and epidural phlegmon. Blood cultures identified C. valvarum as the causative organism. The patient was treated with ceftriaxone and surgical intervention was deferred due to the patient's complex anatomy. His course was complicated by septic cerebral emboli resulting in cerebrovascular accident. CONCLUSIONS: This case report highlights C. valvarum, a rare and emerging HACEK group microorganism that warrants consideration in high-risk patients with evidence of subacute infection and disseminated disease. While C. valvarum classically presents as infective endocarditis, extra-cardiac manifestations have also been described. As demonstrated in this case, endograft involvement and osteomyelitis may occur in rare circumstances.

An unexpected case of Cardiobacterium valvarum prosthetic arthritis without cardiac lesions: Case report and literature review.

We report a case of prosthetic arthritis caused by Cardiobacterium valvarum, which has been exclusively reported to cause intravascular infections. A 81-year-old Japanese female complained prosthetic knee joint pain. Arthrocentesis cultured no pathogen, and surgical replacement of the implant surface was performed. Modified Levinthal medium culture and 16S rRNA sequencing has finally led to diagnosis of C. valvarum prosthetic knee arthritis without cardiac lesions. Fastidious bacteria such as C. valvarum can be candidate pathogens of orthopedic infections whose causative agents are sometimes unidentified. Further development of molecular diagnostics is expected, but also the importance of conventional methods should be noted.

Spontaneous Pyogenic Spondylitis and Possible Infective Endocarditis Caused by Aggregatibacter actinomycetemcomitans.

Aggregatibacter actinomycetemcomitans, an etiological agent associated with periodontitis, endocarditis, and other infections, has rarely been implicated in spondylitis. A 70-year-old man with aortic valve replacement presented with a 4-month history of lower back pain and was diagnosed with spondylitis. Prolonged incubation of blood cultures and a biopsy yielded A. actinomycetemcomitans. Concurrent infective endocarditis (IE) was probable considering the infectious organism and the patients' prosthetic valve. The patient was treated with ceftriaxone and recovered well. Pyogenic spondylitis with possible concurrent IE may be caused by A. actinomycetemcomitans. Extended incubation and repeated cultures should be considered if Haemophilus spp., Aggregatibacter spp, Cardiobacterium spp, Eikenella spp, and Kingella spp. (HACEK) infection is suspected.

Aneurysm of the anterior tibial artery as a complication of infectious endocarditis.

OBJECTIVE: Mycotic aneurysms of the infrapopliteal vessels are rare, with few cases reported in the literature. Management strategies are diverse and should be tailored to the patient's presentation. METHODS: We describe the case of a 40-year-old male who presented with a painful left leg mass in the setting of bacteremia and infective endocarditis. Imaging revealed an aneurysm of the anterior tibial artery. RESULTS: The patient was treated with antibiotics and open surgical repair with excision of the aneurysmal sac, ligation of the anterior tibial artery, and primary repair of the popliteal artery and tibioperoneal trunk. CONCLUSION: The epidemiology, pathophysiology, and clinical management of infrapopliteal aneurysms are briefly reviewed in this case study.

Structural variability of CG-rich DNA 18-mers accommodating double T-T mismatches.

Solution and crystal data are reported for DNA 18-mers with sequences related to those of bacterial noncoding single-stranded DNA segments called repetitive extragenic palindromes (REPs). Solution CD and melting data showed that the CG-rich, near-palindromic REPs from various bacterial species exhibit dynamic temperature-dependent and concentration-dependent equilibria, including architectures compatible with not only hairpins, which are expected to be biologically relevant, but also antiparallel duplexes and bimolecular tetraplexes. Three 18-mer oligonucleotides named Hpar-18 (PDB entry 6rou), Chom-18 (PDB entry 6ros) and its brominated variant Chom-18Br (PDB entry 6ror) crystallized as isomorphic right-handed A-like duplexes. The low-resolution crystal structures were solved with the help of experimental phases for Chom-18Br. The center of the duplexes is formed by two successive T-T noncanonical base pairs (mismatches). They do not deform the double-helical geometry. The presence of T-T mismatches prompted an analysis of the geometries of these and other noncanonical pairs in other DNA crystals in terms of their fit to the experimental electron densities (RSCC) and their geometric fit to the NtC (dinucleotide conformational) classes (https://dnatco.datmos.org/). Throughout this work, knowledge of the NtC classes was used to refine and validate the crystal structures, and to analyze the mismatches.

Pediatric acute dacryocystitis due to Eikenella corrodens: A case report.

Eikenella corrodens is a facultatively anaerobic gram-negative rod bacterium in the oropharynx and respiratory tract. It is a member of HACEK (Haemophilus spp., Aggregatibacter spp., Cardiobacterium hominis, E. corrodens, and Kingella kingae) group commonly associated with endocarditis and craniofacial infections. It is usually susceptible to penicillin, second and third-generation cephalosporins, and carbapenem, but has variable susceptibility to first-generation cephalosporin. We herein provide a description of the first case of pediatric acute dacryocystitis caused by E. corrodens. The patient did not respond to oral cephalexin and required surgical drainage followed by intravenous cefotaxime. Also provided is a brief review of the current literature.

Difficult Gram staining: a case of endocarditis due to Cardiobacterium hominis and review of the literature.

Cardiobacterium hominis est un bacille à Gram négatif responsable d'endocardites infectieuses, principalement chez les patients atteints de pathologies cardiaques ou porteurs de valves. L'identification de cette bactérie est souvent complexe et peut être la cause d'un diagnostic et d'une prise en charge tardifs, source de complications cardiaques. Cet article présente la prise en charge d'une endocardite infectieuse associée à un sepsis à Cardiobacterium hominis, les difficultés d'identification de cette bactérie, ainsi qu'une revue de la littérature sur les infections dues à cette bactérie.

"Double-barrel endocarditis".

We report a case of an 18-year-old woman who presented with infective endocarditis (IE), in two conduits percutaneously delivered in the right ventricle outflow tract ("double-barrel endocarditis"). The patient's clinical presentation, echocardiogram findings, infectious agent, clinical management, surgical approach, and follow-up assessment are described. Percutaneous pulmonary valve implantation has emerged as a viable therapy for conduit dysfunction in the right ventricular outflow tract. Although the percutaneous approach has several advantages, this strategy and the valves used are not complication-free. IE after transcatheter valve deployment has evoked the growing concern, as there is a higher incidence in these patients compared with patients with surgically repaired pulmonary valves. As a result, this type of surgical treatment is especially important.

Infective endocarditis caused by Cardiobacterium hominis endocarditis: A case report and review of the literature.

BACKGROUND: While it has been increasing cases of C. hominis endocarditis in the past decades due to advances of diagnostic methods, the epidemiology and clinical manifestations of IE caused by C. hominis is still unknown. CASE PRESENTATION: A 62-year old man was admitted to our institute with fever, anorexia and general fatigue for the preceding one month. He had a past medical history of both aortic and mitral valves replacement due to cardiac diseases. He was diagnosed as IE caused by C. hominis according to the modified duke criteria. The patient received 2 weeks of combination therapy of intravenous ceftriaxone (CTRX) 2g and gentamycin 180mg daily followed by 4 weeks CTRX 2g daily alone. Oral moxifloxacin 400mg once daily was given for an additional 4 weeks. After the antibiotic therapy was discontinued, disease recurrence was not observed. We reviewed previously reported C. hominis IE cases in 60 publications including ours. Of 73 patients enrolled, 53 were male, the mean age was 52 years. The most common risk factor of IE was past history of cardiac diseases in 44/73 (60%). As for antibiotics initially prescribed, third-generation cephalosporins was most frequently used in 28/69 (41%). While the cure rate was 67/73 (93%), 31/73 patients (43%) received a surgical intervention. Embolic lesions to the central nervous system and vertebrae were seen in 16/72 (22%) and 5/72 (7%). CONCLUSION: IE caused by C. hominis has a favorable prognosis, showing the cure rate of 93%. Physicians should recognize the possible occurrence of emboli among IE patients.

A case report of Guillain Barré syndrome revealing underlying infective endocarditis due to Cardiobacterium hominis.

RATIONALE: Guillain-Barré syndrome (GBS) is an acute inflammatory polyradiculoneuropathy presumed to result from an infection-triggered autoimmune reaction. PATIENT CONCERNS: This paper describes a 53-year-old man admitted to hospital for deterioration of his general condition. DIAGNOSIS: He developed GBS, confirmed by lumbar puncture and electromyogram, which recovered after intravenous immunoglobulins. A grade 2 aortic regurgitation was detected by transthoracic echocardiography upon diagnosis of GBS, but in the absence of fever, no further investigations were conducted. A few weeks later, the patient presented with fever and infective endocarditis (IE) was diagnosed after the identification of vegetation on the aortic valve with transesophageal echocardiography. The etiologic agent was identified as Cardiobacterium hominis based on 3 positive blood cultures and DNA detection in valvular material. INTERVENTIONS: IE was cured with a 6-week course of antibiotics and aortic valve replacement. OUTCOMES: The patient completely recovered from Guillain-Baré syndrome and IE. LESSONS: This case of GBS associated with C hominis endocarditis, emphasizes the importance of blood cultures and transesophageal echocardiography for the detection of IE and highlights the insidious nature of C hominis endocarditis which is often diagnosed late.

Intracranial Hemorrhaging Following Cardiobacterium hominis Endocarditis.

Acute infectious endocarditis (IE) is a complex disease that presents as a serious clinical condition associated with a high mortality rate, especially due to intracranial hemorrhaging (ICH). The most common causative organism is Staphylococcus aureus. We herein report a patient with ICH following subacute IE with a positive blood culture for Cardiobacterium hominis. A review of the existing literature revealed that acute IE associated with Cardiobacterium has been reported to cause ICH in only seven previous cases. Prolonged culture-specific antibiotic therapy along with extended surveillance of blood culture is therefore essential for timely intervention.