Aortitis in a child with Abiotrophia defectiva endocarditis

Abiotrophia defectiva as a cause of infective endocarditis with embolic complications in children

Abiotrophia defectiva is a rare pathogen of infective endocarditis (IE) but is frequently involved in embolic complication and valvular dysfunction. IE caused by A. defectiva in children is poorly studied. This study reports four cases of A. defectiva IE in children and reviews previously reported five pediatric cases of A. defectiva IE. Most of the patients presented with a subacute course, with prolonged fever or atypical symptoms. Eight patients had embolic complications at presentation. All nine children were treated with combination antimicrobial therapy and six of them received surgical intervention. All patients recovered well without relapse. A. defectiva should be considered in children with infective endocarditis, especially in those with atypical presentations. As complications are frequent and more than half of the patients need surgical treatment, prompt diagnosis along with appropriate treatment is necessary.

Aortitis caused by Abiotrophia defectiva: Description of two cases

Abiotrophia defectiva is a well-known endocarditis pathogen, however it has never been described as a cause of primary aortitis. Here we describe the first published case of thoracic aortitis and an unusual case of aortic graft infection due to A. defectiva, which were both managed conservatively.

The potential role of lung microbiota in lung cancer attributed to household coal burning exposures

Bacteria influence site-specific disease etiology and the host's ability to metabolize xenobiotics, such as polycyclic aromatic hydrocarbons (PAHs). Lung cancer in Xuanwei, China has been attributed to PAH-rich household air pollution from burning coal. This study seeks to explore the role of lung microbiota in lung cancer among never smoking Xuanwei women and how coal burning may influence these associations. DNA from sputum and buccal samples of never smoking lung cancer cases (n = 8, in duplicate) and controls (n = 8, in duplicate) in two Xuanwei villages was extracted using a multi-step enzymatic and physical lysis, followed by a standardized clean-up. V1-V2 regions of 16S rRNA genes were PCR-amplified. Purified amplicons were sequenced by 454 FLX Titanium pyrosequencing and high-quality sequences were evaluated for diversity and taxonomic membership. Bacterial diversity among cases and controls was similar in buccal samples (P = 0.46), but significantly different in sputum samples (P = 0.038). In sputum, Granulicatella (6.1 vs. 2.0%; P = 0.0016), Abiotrophia (1.5 vs. 0.085%; P = 0.0036), and Streptococcus (40.1 vs. 19.8%; P = 0.0142) were enriched in cases compared with controls. Sputum samples had on average 488.25 species-level OTUs in the flora of cases who used smoky coal (PAH-rich) compared with 352.5 OTUs among cases who used smokeless coal (PAH-poor; P = 0.047). These differences were explained by the Bacilli species (Streptococcus infantis and Streptococcus anginosus). Our small study suggests that never smoking lung cancer cases have differing sputum microbiota than controls. Further, bacteria found in sputum may be influenced by environmental exposures associated with the type of coal burned in the home.

Abiotrophia endocarditis in children with no underlying heart disease: a rare but a virulent organism

Infective endocarditis is extremely rare in children with structurally normal hearts. The most common etiological agents are staphylococcal and streptococcal species. Nutritionally variant streptococci also classified as Abiotrophia species are a group of fastidious organisms that account for only 5% to 6% of all cases of culture-negative infective endocarditis. Only seven cases of Abiotrophia infective endocarditis have been previously reported in children with no underlying structural heart disease. We report two cases of Abiotrophia infective endocarditis in children without any predisposing factors. Both patients presented with nonspecific symptoms leading to delay in diagnosis. While bacteriological clearance was achieved in both cases, both had a complicated course including development of brain mycotic aneurysms, splenic infarction, renal failure, and irreversible damage to the mitral valve. Both patients required surgical removal of the native mitral valve and replacement. We also present review of seven cases with similar diagnosis published previously in literature and highlight important differences. Our cases highlight special challenges in management of Abiotrophia endocarditis in pediatric patients. As the organism may not be isolated in routine culture media, may present with atypical clinical symptoms and may have a complicated course even without antibiotic failure, a high index of suspicion should be maintained in children with subacute symptoms even with no underlying structural cardiac disease.

Infectious aortitis: a rare cause of chest pain in a child

Infectious aortitis (IA) is a life-threatening bacterial infection that occurs almost exclusively in adults. Only 1 case of IA had been previously reported in a child. We present a case of IA that occurred in a 6.5-year-old previously healthy girl who was seen in our emergency department because of fever and chest pain of immediate onset. She underwent a thorough evaluation but died of aortic rupture before the correct diagnosis was established. The etiology, clinical presentation, diagnosis, and treatment of IA are discussed.

Abiotrophia defectiva: A rare cause of infective endocarditis

A case of Abiotrophia defectiva-caused infective endocarditis is described. The patient was successfully treated with penicillin combined with gentamicin. Due to the fastidious nature of the agent, there is a need for special media for isolation and moreover, there is a need for a future development of susceptibility assays applicable to the organism.

Streptococcal Infections

The streptococci are a large heterogeneous group of gram-positive spherically shaped bacteria widely distributed in nature. They include some of the most important agents of human disease as well as members of the normal human flora. Some streptococci have been associated mainly with disease in animals, while others have been domesticated and used for the culture of buttermilk, yogurt, and certain cheeses. Those known to cause human disease comprise two broad categories: First are the pyogenic streptococci, including the familiar β-hemolytic streptococci and the pneumococcus. These organisms are not generally part of the normal flora but cause acute, often severe, infections in normal hosts. Second are the more diverse enteric and oral streptococci, which are nearly always part of the normal flora and which are more frequently associated with opportunistic infections.