Cardiobacterium hominis endocarditis: A case report and review of the literature

Cardiobacterium hominis infective endocarditis: A literature review

Background

Cardiobacterium hominis is a member of the HACEK group, which causes infective endocarditis (IE) but is rarely associated with other infections. It is difficult to biologically identify C. hominis because of its slow growth in culture. However, the clinical features of C. hominis IE remain unclear.

Method

We searched the PubMed database for all articles of C. hominis IE published between January 2000 and July 2022.

Results

The major clinical features of 44 previously reported cases of C. hominis IE were as follows: the median age was 59 years, of which 36 were men; the initial presenting symptoms were chest discomfort (30 %), followed by fever (27 %), night sweats (20 %), fatigability (18 %), weight loss (16 %), and dyspnea (16 %). Almost half of the patients were febrile upon admission. The major predisposing factors were postsurgical valve treatment (57 %), dental treatment or caries (20 %), and congenital valve abnormality (5 %). The median time to identify C. hominis in the blood culture was 4 days, but the longest time was 42 days. The most commonly infected valve was the aortic valve, and the most common complication was systemic embolism. Surgical treatment was performed in 23 (52 %) patients. The most frequent initial treatment regimen was cephem antibiotics, with a median treatment duration of 6 weeks. The overall mortality and recovery rates of C. hominis IE were 9 % and 91 %, respectively.

Conclusion

If C. hominis infection is confirmed, physicians should check for the presence of vegetations of the heart valves and understand these characteristics.

Infective endocarditis by HACEK: a review

Infective endocarditis (IE) is a severe disease that is still associated with high mortality despite recent advances in diagnosis and treatment. HACEK organisms (Haemophilus spp., Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae) are gram-negative bacteria that are part of the normal flora of the mouth and upper respiratory tract in humans. These organisms cause a wide range of infections, of which IE is one of the most notable. In order to control and prevent endocarditis caused by HACEK, measures such as oral hygiene and the use of prophylactic drugs should be used for people at risk, including people with underlying heart disease and people with artificial valves. This review is a summary of the main aspects of IE focusing on HACEK organisms.

A Case Report of Cardiobacterium hominis Endocarditis in a Pregnant Woman

Infective endocarditis (IE) is an infrequent endovascular disease, which can result in significant mortality and morbidity. Staphylococcus aureus and viridans streptococci remain the most common etiological agent. Cardiobacterium hominis, a member of the HACEK (Haemophilus species, Aggregatibacter species, Cardiobacterium hominis, Eikenella corrodens, and Kingella species) group of fastidious gram-negative bacillus, is a part of normal upper respiratory flora and a rare cause implicated in IE. Cases of Cardiobacterium hominis endocarditis are being increasingly reported in last few years due to advancement in automated blood culture system such as BacT/ALERT Virtuo^® and identification system such as MALDI-TOF MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry). We herein report a first case of Cardiobacterium hominis endocarditis in a pregnant woman at 20 weeks of gestation. Following spontaneous abortion and evacuation of the fetus, appropriate surgical intervention under heparinized condition and pathogen-directed medical intervention was initiated in this patient. This case report highlights the importance of appropriate antimicrobial therapy, which augments earlier resolution of the disease.

Obstructive heart failure with Cardiobacterium hominis infective endocarditis

We illustrate the progression of Cardiobacterium hominis infective endocarditis in a patient with a bioprosthetic mitral valve and decompensated heart failure secondary to an obstructive septic vegetation.

Maintenance of the aseptic working field during endodontic treatment

Objective: The aim of this clinical quality study was to determine whether the aseptic working field is maintained during the endodontic procedure. Materials and methods: Bacterial samples were collected from the rubber dam of 27 patients during endodontic treatment performed by postgraduate students at the Department of Endodontics, University of Oslo. A bacterial sample was first obtained immediately after disinfection of the working field (A), and the second sample was collected just before obturation or dressing with calcium hydroxide cement (B). Aerobic cultivation technique and PCR were used for detection of bacterial growth and species. Results: All samples were negative on culturing except in one case, which showed positive results with cultivation in both sample A and B. Specie detected with cultivation technique were Streptococcus mitis. With PCR technique, 6 samples in 5 patients (11%), showed positive results. Species detected with PCR technique were Bacteroidales spp. Propionibacterium spp., Bacteroidetes spp., Prevotella nigrescens, Haemophilus parainfluenzae, Neisseria elongata, Alloprevotella tannerae, Capnocytophaga granulosa, Cardiobacterium hominis, Fusobacterium nucleatum and Streptococcus mitis. Conclusion: The present study showed that an aseptic working field was maintained throughout the endodontic procedure in 81% (22/27) of the cases after disinfection of the rubber dam.

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.

Permanent pacemaker-associated actinomycetemcomitans endocarditis: A case report

Aggregatibacter actinomycetemcomitans is a Gram-negative bacillus, member of the HACEK group of bacteria, and it is a very rare cause of endocarditis. It is also an extremely rare cause of device-associated infection of the heart. We describe the case of a 25 year-old man who presented with pacemaker-associated endocarditis due to Aggregatibacter actinomycetemcomitans and also discuss the implications and treatment of this organism.

A pediatric case of cardiobacterium hominis endocarditis

Gram negative endocarditis is relatively rare in pediatrics but when they occur they are most frequently caused by one of the HACEK (Haemophilus species, Actinobacillus actinomycetemcomitans, C. hominis, Eikenella corrodens and Kingella kingae) group of microorganisms. Within the HACEK group of microorganisms there have been approximately 100 cases of Cardiobacterium hominis endocarditis reported in the literature, but only 2 previous cases of endocarditis and one case of pericarditis have been reported in children. In this report, we present a case of a 12-year-old boy with a right ventricle to pulmonary artery conduit for Tetralogy of Fallot with pulmonary atresia who presented at an annual cardiology examination with a 3 week history of fatigue and was found to have a vegetation on routine echocardiogram. Subsequent blood cultures grew Cardiobacterium hominis and the patient was treated successfully with 6 weeks of appropriate antibiotic therapy. We present this case and a review of the literature of the HACEK group of microorganisms in pediatrics.

Cardiobacterium hominis prosthetic valve endocarditis: an infrequent infection

A case of prosthetic aortic valve endocarditis due to Cardiobacterium hominis in a 67-year-old woman is described. The diagnosis was confirmed by a positive blood culture and echocardiographic detection of aortic valve vegetations. The patient underwent replacement of the valve with a homograft, and received antibiotics postoperatively. She remained well after 12 months.

Infective endocarditis in a child caused by Cardiobacterium hominis after right ventricular outflow tract reconstruction using an expanded tetrafluoroethylene conduit

Cardiobacterium hominis, a member of the HACEK group of organisms, is a rare cause of endocarditis. We report a case of infective endocarditis caused by C. hominis in a male child who had undergone right ventricular outflow tract (RVOT) reconstruction using an expanded polytetrafluoroethylene conduit for tetralogy of Fallot with pulmonary atresia. Two days before admission, the patient suffered from exertional shortness of breath. Right ventricular hypertension was confirmed and RVOT stenosis was suspected based on the echocardiography findings. A CT scan revealed vegetation above the cusp of the conduit. An emergency operation was performed to avoid a pulmonary embolism due to large friable vegetation. C. hominis was cultured from the blood and the vegetation, prompting a diagnosis of prosthetic valve endocarditis. The patient was discharged after a 6-week course of intravenous ceftriaxone therapy.

Cardiobacterium hominis endocarditis presenting as acute embolic stroke: a case report and review of the literature

We report on a case of endocarditis attributable to Cardiobacterium hominis in a 31-year-old man who presented with acute-onset, left-sided hemiparesthesia. Magnetic resonance imaging of the brain showed acute infarctions in 2 areas of the right cerebral cortex, and a transesophageal echocardiogram revealed vegetation in a previously unrecognized bicuspid aortic valve. The patient completed a 6-week course of ceftriaxone and aspirin, with resolution of the vegetation and neurological complications. Our literature review of C. hominis endocarditis suggests that aortic-valve involvement is associated with high stroke and valve-surgery rates. Favorable outcomes and treatment success are evident with either penicillin or ceftriaxone, in combination with (if indicated) valve surgery in patients with neurological complications.

Detection of Cardiobacterium valvarum in a patient with aortic valve infective endocarditis by broad-range PCR

Cardiobacterium valvarum, a fastidious Gram-negative bacterium, was detected in the aortic valve of a previously healthy 63-year-old man by broad-range PCR and 16S rRNA gene sequencing. In contrast to the patients in five previously published cases, our patient had neither a congenital bicuspid nor a prosthetic aortic valve. Here, we present a case of C. valvarum native tricuspid aortic valve infective endocarditis and a review of the literature.