Broad-range polymerase chain reaction for the diagnosis of Bartonella henselae endocarditis

Infectious Complications of DiGeorge Syndrome in the Setting of Malignancy

This report describes a case of a young man with DiGeorge Syndrome, repaired Tetralogy of Fallot, relapsed metastatic Hodgkin’s Lymphoma, immunodeficiency, and a history of recurrent and severe infections. A review of the literature indicates that patients with DiGeorge Syndrome are at greater risk for infection, malignancy, and cardiac events due to anatomic and immunologic complications resulting from a deletion in the 22q11.2 chromosome. As an increased number of patients with DiGeorge Syndrome are surviving into adulthood, it is important to understand the progression of the disease and the long-term implications associated with variable degrees of thymic hypoplasia and immune deficiency. 

Utility of Broad-Range PCR Sequencing for Infectious Diseases Clinical Decision Making: a Pediatric Center Experience

Broad-range PCR (BRPCR) sequencing is a promising tool for diagnosis of infectious conditions when traditional microbiologic strategies fail to identify a pathogen. Data on the optimal clinical scenarios in which to use this tool are limited.

Bartonella endocarditis in patients with right ventricle-to-pulmonary artery conduit: 2 case reports and literature review

Bartonella species are Gram-negative bacilli and fastidious bacteria that can cause a number of clinical syndromes, including blood culture-negative infective endocarditis (IE). The two most commonly isolated species in humans are Bartonella quintana, the agent of trench fever, and Bartonella henselae, mostly known for causing cat scratch disease (Edouard et al., 2015 [1]; Edouard and Raoult, 2010 [2]). Both species also cause bacillary angiomatosis, primarily in immunocompromised patients (Edouard et al., 2015 [1]; Fournier et al., 2001 [3]). The risk of B. henselae IE is increased in patients with cardiac valvular disease and congenital heart disease (CHD) (Edouard and Raoult, 2010 [2]; Das et al., 2009 [4]; Abandeh et al., 2012 [5]; Ouellette et al., 2016 [6]; Hoffman et al., 2007 [7]; Georgievskaya et al., 2014 [8]). In this article, we detail two cases of Bartonella IE in patients with right ventricle-to-pulmonary artery (RV-PA) conduits who presented to our institution. We also perform a literature review on Bartonella IE in patients with a history of RV-PA conduit or pulmonary valve replacement.

Coronary artery embolism and culture-negative endocarditis post Bentall's procedure

Infective endocarditis is an important cause of morbidity and mortality, which classically presents with fevers and nonspecific symptoms. Afebrile infective endocarditis with negative blood cultures makes diagnosis more challenging and delays in treatment can occur increasing the likelihood of complications. The presence of prosthetic heart valves places patients at an increased risk of infective endocarditis and the case described below highlights the importance of considering this diagnosis even if classic clinical features such as fever and raised inflammatory markers are not present, as well as discussing an unusual complication of infective endocarditis; coronary artery embolism leading to myocardial infarction.

Chest Imaging of a rare case of cat-scratch disease in a 2-years-old baby

Cat-scratch disease (CSD) is usually a self-limiting infection that in the majority of cases occurs as lymphadenitis in children who have been scratched or bitten by a cat. Rarely, Bartonella henselae is cause of fever of unknown origin (FUO), with dissemination to various organs, mimicking an inflammatory rather than a lymphoproliferative disease. This manuscript will present a case of thoracic manifestations of CSD in an immunocompetent 2-years baby without history of cat contact, with fever of unknown origin, investigated by chest CT and MRI. (www.actabiomedica.it)

Bartonella quintana, an Unrecognized Cause of Infective Endocarditis in Children in Ethiopia

Bartonella quintana endocarditis, a common cause of culture-negative endocarditis in adults, has rarely been reported in children. We describe 5 patients 7-16 years of age from Ethiopia with heart defects and endocarditis; 4 cases were caused by infection with B. quintana and 1 by Bartonella of undetermined species. All 5 patients were afebrile and oligosymptomatic, although 3 had heart failure. C-reactive protein was normal or slightly elevated, and erythrocyte sedimentation rate was high. The diagnosis was confirmed by echocardiographic demonstration of vegetations, the presence of high Bartonella IgG titers, and identification of B. quintana DNA in excised vegetations. Embolic events were diagnosed in 2 patients. Our data suggest that B. quintana is not an uncommon cause of native valve endocarditis in children in Ethiopia with heart defects and that possible B. quintana infection should be suspected and pursued among residents of and immigrants from East Africa, including Ethiopia, with culture-negative endocarditis.

Multiorgan Involvement Confounding the Diagnosis of Bartonella henselae Infective Endocarditis in Children With Congenital Heart Disease

Two children with congenital heart disease status post surgical correction presented with prolonged constitutional symptoms, hepatosplenomegaly and pancytopenia. Concern for malignancy prompted bone marrow biopsies that were without evidence thereof. In case 1, echocardiography identified a multilobulated vegetation on the conduit valve. In case 2, transthoracic, transesophageal and intracardiac echocardiography were performed and were without evidence of cardiac vegetations; however, pulmonic emboli raised concern for infective endocarditis. Both patients underwent surgical resection of the infected material and had histopathologic evidence of infective endocarditis. Further diagnostics identified elevated cytoplasmic antineutrophil cytoplasmic antibodies and antiproteinase 3 antibodies in addition to acute kidney injury with crescentic glomerulonephritis on renal biopsy. Serologic evidence of infection with Bartonella henselae was observed in both patients. These 2 cases highlight the potential multiorgan involvement that may confound the diagnosis of culture-negative infective endocarditis caused by B. henselae.

Bartonella henselae endocarditis and glomerulonephritis with dominant C3 deposition in a 21-year-old male with a Melody transcatheter pulmonary valve: case report and review of the literature

We report a case of a 21-year-old young man with underlying congenital heart disease who developed Bartonella henselae endocarditis of the right ventricular outflow tract (RVOT) conduit of his Melody transcatheter (percutaneous) pulmonary valve (TPV), with an initial presentation of glomerulonephritis with a dominant C3 pattern, with renal failure and circulating cryoglobulins. There are few reports of a glomerulonephritis with a dominant C3 pattern presenting as a manifestation of B. henselae endocarditis. While most cases of B. henselae endocarditis affect the aortic valve, in this case the valve damage was to the RVOT of the Melody TPV, a percutaneous transcatheter valve delivery system that had previously replaced his pulmonary homograft, which had become dysfunctional as a result of prior Streptococcus viridans endocarditis. The pulmonary homograft had been in place since childhood as a result of a Ross procedure to repair his congenital aortic stenosis. The patient's renal failure significantly improved after surgical resection of the infected RVOT and institution of appropriate antibiotic therapy.

Molecular diagnosis of bacterial infective endocarditis in tabriz, azerbaijan

INTRODUCTION

The aim of this study was to analyze a PCR based approach for detection of infective endocarditis in Azerbaijan.

METHODS

Ten aortic valves, 8 mitral valves and 2 tricuspid valves, were analyzed for the presence of bacterial infective endocarditis using Gram staining, culture and PCR methods.

RESULTS

Of the 20 valves, 5 and 4 cases were positive by Gram staining and culture assay, respectively. Bacterial DNA was positive in 12 of the 20 valves (60%) by broad-spectrum PCR. Direct sequencing for species identification was possible in 10 cases.

CONCLUSION

PCR and direct molecular identification of the etiological agents responsible for infective endocarditis may enable specific treatment to begin at an earlier phase of the disease.

Association of Bartonella spp bacteremia with Chagas cardiomyopathy, endocarditis and arrhythmias in patients from South America

Infection with Bartonella spp may cause cardiac arrhythmias, myocarditis and endocarditis in humans. The aim of the present study was to evaluate a possible association between Bartonella spp bacteremia and endocarditis, arrhythmia and Chagas cardiomyopathy in patients from Brazil and Argentina. We screened for the presence of bacterial 16S rRNA in human blood by PCR using oligonucleotides to amplify a 185-bp bacterial DNA fragment. Blood samples were taken from four groups of subjects in Brazil and Argentina: i) control patients without clinical disease, ii) patients with negative blood-culture endocarditis, iii) patients with arrhythmias, and iv) patients with chronic Chagas cardiomyopathy. PCR products were analyzed on 1.5% agarose gel to visualize the 185-bp fragment and then sequenced to confirm the identity of DNA. Sixty of 148 patients (40.5%) with cardiac disease and 1 of 56 subjects (1.8%) from the control group presented positive PCR amplification for Bartonella spp, suggesting a positive association of the bacteria with these diseases. Separate analysis of the four groups showed that the risk of a Brazilian patient with endocarditis being infected with Bartonella was 22 times higher than in the controls. In arrhythmic patients, the prevalence of infection was 45 times higher when compared to the same controls and 40 times higher for patients with Chagas cardiomyopathy. To the best of our knowledge this is the first report of the association between Bartonella spp bacteremia and Chagas disease. The present data may be useful for epidemiological and prevention studies in Brazil and Argentina.

Identification of candidate proteins for the diagnosis of Bartonella henselae infections using an immunoproteomic approach

Bartonella henselae is an emerging gram-negative facultative intracellular pathogen transmitted via Ctenocephalides felis (cat fleas) or cat scratches. Bartonellosis is present mainly in the form of cat scratch disease (CSD), bacillary angiomatosis and infective endocarditis (IE). The methods used to diagnose B. henselae rely on culturing, immunofluorescent assays and molecular techniques. The objective of the present study was to identify candidate proteins for the serodiagnosis of bartonellosis with the differential discrimination of both clinical scenarios: CSD and IE. For this, an immunoproteomic approach combined with 2-DE, immunoblotting and matrix-assisted laser desorption/ionization time-of-flight MS has been developed. Immunoproteomic profiles of sera collected from patients with CSD and IE were compared with those of blood donors. We identified several candidate proteins as phage-encoding Pap31 protein and an outer membrane protein of BH11510 that, in our view, might be useful for the serodiagnosis of bartonellosis.

Culture negative endocarditis caused by Bartonella henselae in a child with congenital heart disease

A 9-year-old white male with congenital aortic and subaortic stenosis palliated by the Ross-Konno procedure presented with culture-negative endocarditis. Serologic studies and polymerase chain reaction testing of resected homograft valvular tissue provided evidence of Bartonella henselae as the etiology. B. henselae can cause endocarditis in children, particularly those with underlying valvular disease. Serologic testing for B. henselae should be considered in children with culture-negative endocarditis.

Culture-negative infectious endocarditis caused by Bartonella spp.: 2 case reports and a review of the literature

Bartonella spp. are rare pathogens in humans and were recently recognized as important causative agents of culture-negative endocarditis. Here, we describe the 1st 2 documented cases of culture-negative endocarditis due to Bartonella henselae and Bartonella quintana encountered in a single hospital in Germany. Infection of the heart valve tissue was detected by broad-range polymerase chain reaction (PCR) and further confirmed by serologic testing. In particular, acute B. henselae infection with an impressive bacterial colonization of the infected cardiac valve was illustrated by transmission electron microscopy. B. henselae was further characterized by PCR assays targeting genotype-specific regions. Disease progression was initially monitored over the entire infection episode through inflammatory markers. In addition, a short overview of published detailed cases of Bartonella endocarditis in Europe within the last 7 years is given.

Bivalvular Bartonella henselae prosthetic valve endocarditis

Prosthetic valve endocarditis is an uncommon manifestation of infection with Bartonella species. Herein, we report a case of Bartonella henselae endocarditis involving prosthetic mitral and aortic valves. The patient had a favorable outcome with combined medical and surgical therapy. Concomitant crescentic glomerulonephritis led to an initial mistaken diagnosis of Wegener's granulomatosis.

Role of magnetic resonance imaging and scintigraphy in the diagnosis and follow-up of osteomyelitis in cat-scratch disease

Cat-scratch disease (CSD) is a self-limiting infectious disease characterised with lymphadenopathy in a patient with a history of cat contact. Cases of bone involvement in patients with CSD are rare. We reported a case of 11-year-old boy with prolonged intermittent fever, inguinal lymphadenopathy and osteomyelitis. He had a history of exposure to kittens. The physical examination revealed a febrile boy without an apparent site of infection except an enlarged inguinal lymph node. Its histopathology demonstrated granulomatous lesion with no presence of acid-fast bacilli. Serum titers for Bartonella henselae were positive. Multiple bone lesions were detected by skeletal scintigraphy. Magnetic resonance imaging (MRI) confirmed and characterised osteolytic masses. The oral combination of azithromycin and rifampicin were given for 6 weeks with a good clinical response. At follow-up, the boy was without symptoms or signs of the disease. Successive MRI controls showed gradual regression of the bone lesions together with significant decrease of acute-phase reactants. In conclusion, CSD should be considered in the differential diagnosis of osteomyelitis. MRI is more reliable for the characterisation, evaluation of soft-tissue extension and follow-up of the bone lesions than scintigraphy. However, the later method permits an overview of the multiple osseous lesions. Therefore, standard MRI equipment may not exclude bone scintigraphy. Both methods are required until whole-body MRI units become routine.