Bartonella Endocarditis in Spain: Case Reports of 21 Cases

A case of Bartonella vinsonii endocarditis

The diagnosis of Bartonella is challenging due to its rarity and negative culture results. Once the diagnosis is delayed and proper treatment is not given, it can develop into infective endocarditis, which can be fatal. We reported a 60-year-old female patient who had recurrent fever for 5 months. After receiving ineffective treatment at the local hospital, she sought medical attention at our hospital. Laboratory blood indicators testing and imaging indicated infective endocarditis, and metagenomic Next Generation Sequencing (m-NGS) testing confirmed the diagnosis of Bartonella vinsonii infection. After surgical treatment and the combination of doxycycline and ceftriaxone sodium for anti-infective therapy, the patient recovered. Valuing the combination of multiple auxiliary diagnostic methods and improving the application of m-NGS in the detection of unknown pathogens can compensate for the current limitations in the diagnosis of Bartonella. Early diagnosis and treatment are extremely important for Bartonella endocarditis.

Bartonella quintana pulmonary native valve endocarditis

Bartonella quintana is a well-known cause of blood culture-negative endocarditis; however, pulmonary valve involvement is rare. The case of a 40-year-old African male who presented to the Emergency Department with chest pain, cardiac failure, and a 2-week history of fever is presented. Transoesophageal echocardiography confirmed an atrial septal defect, severe pulmonary insufficiency with large vegetations, severe mitral regurgitation due to anterior leaflet prolapse, and right ventricular dysfunction. Empirical antibiotic therapy was started, and urgent surgical intervention was decided. There were vegetations on the three pulmonary valve leaflets and the mitral valve. Closure of the atrial septal defect, mitral and tricuspid valve repair, pulmonary valve replacement with a biological prosthesis, and infundibuloplasty of the right ventricle were performed. The postoperative course was uneventful. Preoperative blood cultures were negative, and B. quintana was detected through 16S rRNA gene amplification and sequencing in mitral and pulmonary implants. Serology showed positive titers of 1/1260 for both B. quintana and B. henselae. Ceftriaxone and gentamicin were administered for 10 days, followed by oral doxycycline for 12 weeks. A one-year echocardiogram showed normal functioning of the pulmonary prosthesis and the mitral and tricuspid repair. Infection caused by B. quintana is a rare cause of endocarditis with negative blood cultures, and multivalvular and pulmonary valve involvement is exceptional.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-024-01727-4.

Bartonella quintana Endocarditis: A Systematic Review of Individual Cases

BACKGROUND

Bartonella quintana is a louse-borne bacterium that remains a neglected cause of endocarditis in low-resource settings. Our understanding of risk factors, clinical manifestations, and treatment of B. quintana endocarditis are biased by older studies from high-income countries.

METHODS

We searched Pubmed Central, Medline, Scopus, Embase, EBSCO (CABI) Global Health, Web of Science and international trial registers for articles published before March 2023 with terms related to Bartonella quintana endocarditis. We included articles containing case-level information on B. quintana endocarditis and extracted data related to patient demographics, clinical features, diagnostic testing, treatment, and outcome.

RESULTS

A total of 975 records were identified, of which 569 duplicates were removed prior to screening. In total, 84 articles were eligible for inclusion, describing a total of 167 cases. Infections were acquired in 40 different countries; 62 cases (37.1%) were acquired in low- and middle-income countries (LMICs). Disproportionately more female and pediatric patients were from LMICs. More patients presented with heart failure (n = 70/167 [41.9%]) than fever (n = 65/167 [38.9%]). Mean time from symptom onset to presentation was 5.1 months. Also, 25.7% of cases (n = 43/167) were associated with embolization, most commonly to the spleen and brain; 65.5% of antimicrobial regimens included doxycycline. The vast majority of cases underwent valve replacement surgery (n = 154/167, [98.0%]). Overall case fatality rate was 9.6% (n = 16/167).

CONCLUSIONS

B. quintana endocarditis has a global distribution, and long delays between symptom onset and presentation frequently occur. Improved clinician education and diagnostic capacity are needed to screen at-risk populations and identify infection before endocarditis develops.

Cat Scratch Endocarditis

We reported a case of blood culture-negative infective endocarditis on a native valve, where the clinical presentation was exclusively related to extensive cerebral ischemia secondary to multiple systemic septic cardioembolic events. The cause was ascribed to subacute Bartonella henselae infection, presumably transmitted by cat scratch, documented by positive serologic findings.

Infection status and molecular detection of pathogens carried by ectoparasites of Miniopterus fuliginosus bats in Yunnan, China

Bats serve as natural hosts for various infectious agents that can affect both humans and animals, and they are geographically widespread. In recent years, the prevalence of bat-associated pathogens has surged on a global scale, consequently generating significant interest in bats and their ectoparasites. In this study, we specifically selected the Miniopterus fuliginosus as the host and conducted bat captures in Nanjian Yi Autonomous County, Dali Bai Autonomous Prefecture, and the other in Mouding Township, Chuxiong Yi Autonomous Prefecture, located in Yunnan Province, China. Ectoparasites were meticulously collected from the bat body surface, alongside blood samples for subsequent analyses. Following collection, the ectoparasites were methodically identified and subjected to comprehensive ecological analysis. Additionally, DNA was extracted from both the bat blood and bat flies, with conventional PCR techniques utilized for molecular screening of four pathogens: Anaplasma sp., Babesia sp., Hepatozoon sp., and Bartonella sp. The capture efforts yielded a total of 37 M. fuliginosus, from which 388 ectoparasites were recovered, including 197 gamasid mites (Cr = 50.77%, PM = 94.59%, MA = 5.32, MI = 5.63) and 191 bat flies (Cr = 49.23%, PM = 75.68%, MA = 5.16, MI = 6.82). Notably, Steatonyssus nyctali (Y = 0.28, m*/m = 2.44) and Nycteribia allotopa (Y = 0.23,m*/m = 1.54) predominated among different individuals of M. fuliginosus, exhibiting an aggregated distribution pattern. The infection rates of Bartonella sp. were identified to be 18.92% (7/37) among bats and 37.17% (71/191) among bat flies, based on the testing of 37 bats and 191 bat flies. Phylogenetic analysis demonstrated that the Bartonella sequences exhibited similarity to those found in bats and bat flies within China and South Korea. This study not only contributes to our comprehension of ectoparasite infection in M. fuliginosus but also establishes a foundation for potential exploration of their role as vectors.

Bartonella- and Borrelia-Related Disease Presenting as a Neurological Condition Revealing the Need for Better Diagnostics

The diagnostic tests available to identify vector-borne pathogens have major limitations. Clinicians must consider an assortment of often diverse symptoms to decide what pathogen or pathogens to suspect and test for. Even then, there are limitations to the currently available indirect detection methods, such as serology, or direct detection methods such as molecular tests with or without culture enrichment. Bartonella spp., which are considered stealth pathogens, are particularly difficult to detect and diagnose. We present a case report of a patient who experienced a spider bite followed by myalgia, lymphadenopathy, and trouble sleeping. She did not test positive for Bartonella spp. through clinically available testing. Her symptoms progressed and she was told she needed a double hip replacement. Prior to the surgery, her blood was submitted for novel molecular testing, where Bartonella spp. was confirmed, and a spirochete was also detected. Additional testing using novel methods over a period of five years found Bartonella henselae and Borrelia burgdorferi in her blood. This patient's case is an example of why new diagnostic methods for vector-borne pathogens are urgently needed and why new knowledge of the variable manifestations of Bartonellosis need to be provided to the medical community to inform and heighten their index of suspicion.

Case series of 12 Bartonella quintana endocarditis from the Southwest Indian Ocean

BACKGROUND

Bartonella spp. are fastidious bacteria frequently identified as the cause of blood culture-negative (BCN) endocarditis. However, Bartonella infections are difficult to diagnose in routine laboratory testing and their incidence is probably underestimated. We investigated the epidemiological and clinical features of Bartonella endocarditis cases diagnosed between 2009 and 2021 on Reunion Island (Southwest Indian Ocean).

METHOD

We retrospectively included all patients diagnosed with Bartonella endocarditis at Reunion Island University Hospital during this period. Endocarditis was diagnosed on the basis of microbiological findings, including serological tests (IFA) and PCR on cardiac valves, and the modified Duke criteria. We used then the multispacer typing (MST) method to genotype the available Bartonella strains.

FINDINGS

We report 12 cases of B. quintana endocarditis on Reunion Island (83.3% in men, median patient age: 32 years). All the patients originated from the Comoros archipelago. The traditional risk factors for B. quintana infection (homelessness, alcoholism, exposure to body lice) were absent in all but two of the patients, who reported head louse infestations in childhood. Previous heart disease leading to valve dysfunction was recorded in 50% of patients. All patients underwent cardiac valve surgery and antimicrobial therapy with a regimen including doxycycline. All patients presented high C-reactive protein concentrations, anemia and negative blood cultures. The titer of IgG antibodies against Bartonella sp. exceeded 1:800 in 42% of patients. Specific PCR on cardiac valves confirmed the diagnosis of B. quintana endocarditis in all patients. Genotyping by the MST method was performed on four strains detected in preserved excised valves and was contributive for three, which displayed the MST6 genotype.

CONCLUSIONS

Bartonella quintana is an important cause of infective endocarditis in the Comoros archipelago and should be suspected in patients with mitral valve dysfunction and BCN from this area.

Development and validation of a real-time PCR test to detect Bartonella quintana in clinical samples

This study reports on the validation of a real-time polymerase chain reaction test targeting the vomp region of Bartonella quintana. The assay displayed 100% sensitivity and specificity for the 52 bloods and 159 cultures tested. Molecular diagnosis of Bartonella quintana can aid clinical treatment during acute infection.

"Let the Cat Out of the Heart": Clinical Characteristics of Patients Presenting With Blood Culture-Negative Endocarditis Due to Bartonella Species

Patients with blood culture-negative endocarditis due to Bartonella infection frequently presented with fever, cytopenias, kidney failure, and positive PR3-ANCA. Bartonella IgG titers were variable. Patients commonly underwent surgery with overall low mortality.

Identification of Novel Bartonella washoensis Sequence Type 22 in Marmota himalayana - Jiuquan City, Gansu Province, China, 2021-2022

What is already known about this topic?

The prevalence of rodent-adapted Bartonella species has been increasing significantly. However, the specific Bartonella species carried by Marmota himalayana (M. himalayana), a large rodent species, and the potential risk it poses to human populations remain unknown.

What is added by this report?

Bartonella washoensis (B. washoensis), associated with human endocarditis, was initially identified in M. himalayana, exhibiting a detection rate of approximately one-third and demonstrating a predilection for the heart and lungs. The discovery of the novel Sequence Type 22 has expanded both the isolation source and genetic lineage of B. washoensis.

What are the implications for public health practice?

Individuals residing within the M. himalayana plague focus are at an elevated risk for B. washoensis infection. Consequently, there is a pressing need for public health warnings and efficient clinical case identification in this population.

The Role of Platelets in Infective Endocarditis

Over the last decade, the incidence of infective endocarditis (IE) has increased, with a change in the frequency of causative bacteria. Early evidence has substantially demonstrated the crucial role of bacterial interaction with human platelets, with no clear mechanistic characterization in the pathogenesis of IE. The pathogenesis of endocarditis is so complex and atypical that it is still unclear how and why certain bacterial species will induce the formation of vegetation. In this review, we will analyze the key role of platelets in the physiopathology of endocarditis and in the formation of vegetation, depending on the bacterial species. We provide a comprehensive outline of the involvement of platelets in the host immune response, investigate the latest developments in platelet therapy, and discuss prospective research avenues for solving the mechanistic enigma of bacteria-platelet interaction for preventive and curative medicine.