Geese as reservoirs of human colon cancer-associated Streptococcus gallolyticus.

Recently, an increased number of reports have described pathogens of animal origin that cause a variety of infections and a rise in their transmission to humans. Streptococcus gallolyticus, a member of the Streptococcus bovis/Streptococcus equinus complex (SBSEC), is one of these pathogens and infects a wide range of hosts from mammals to poultry and has a broad functionality ranging from pathogenicity to food fermentation. As S. gallolyticus causes complications including bacteremia, infective endocarditis, and colorectal malignancy in humans, it is important to investigate its occurrence in various hosts, including geese, to prevent potential zoonotic transmissions. This study aimed to investigate the presence of S. gallolyticus in the droppings of clinically healthy and diarrheic geese, which were raised intensively and semi-intensively, by the in vitro culture method, characterize the isolates recovered by PCR and sequence-based molecular methods and determine their antibiotic susceptibility by the disk diffusion and gradient test methods. For this purpose, 150 samples of fresh goose droppings were used. Culture positivity for S. gallolyticus was determined as 8% (12/150). PCR analysis identified 54.55% (n = 6) of the isolates as S. gallolyticus subsp. gallolyticus and 45.45% (n = 5) as S. gallolyticus subsp. pasteurianus. Following the 16S rRNA sequence and ERIC-PCR analyses, S. gallolyticus subspecies exhibited identical cluster and band profiles that could be easily distinguished from each other and were clonally identified. High rates of susceptibility to florfenicol, penicillin, rifampicin, and vancomycin were detected among the isolates, regardless of the subspecies diversity. Both subspecies showed high levels of resistance to bacitracin, clindamycin, doxycycline, tetracycline, trimethoprim-sulfamethoxazole, and erythromycin and multiple MDR profiles, indicating their potential to become superbugs. This first report from Türkiye demonstrates the occurrence of the S. gallolyticus subspecies in geese. In view of the recent increase of geese production and the consumption of goose meat in Türkiye, the occurrence of S. gallolyticus in geese should not be ignored to prevent zoonotic transmission.

Integration of molecular docking and molecular dynamics simulations with subtractive proteomics approach to identify the novel drug targets and their inhibitors in Streptococcus gallolyticus.

Streptococcus gallolyticus (Sg) is a non-motile, gram-positive bacterium that causes infective endocarditis (inflammation of the heart lining). Because Sg has gained resistance to existing antibiotics and there is currently no drug available, developing effective anti-Sg drugs is critical. This study combined core proteomics with a subtractive proteomics technique to identify potential therapeutic targets for Sg. Several bioinformatics approaches were used to eliminate non-essential and human-specific homologous sequences from the bacterial proteome. Then, virulence, druggability, subcellular localization, and functional analyses were carried out to specify the participation of significant bacterial proteins in various cellular processes. The pathogen's genome contained three druggable proteins, glucosamine-1phosphate N-acetyltransferase (GlmU), RNA polymerase sigma factor (RpoD), and pantetheine-phosphate adenylyltransferase (PPAT) which could serve as effective targets for developing novel drugs. 3D structures of target protein were modeled through Swiss Model. A natural product library containing 10,000 molecules from the LOTUS database was docked against therapeutic target proteins. Following an evaluation of the docking results using the glide gscore, the top 10 compounds docked against each protein receptor were chosen. LTS001632, LTS0243441, and LTS0236112 were the compounds that exhibited the highest binding affinities against GlmU, PPAT, and RpoD, respectively, among the compounds that were chosen. To augment the docking data, molecular dynamics simulations and MM-GBSA binding free energy were also utilized. More in-vitro research is necessary to transform these possible inhibitors into therapeutic drugs, though computer validations were employed in this study. This combination of computational techniques paves the way for targeted antibiotic development, which addresses the critical need for new therapeutic strategies against S. gallolyticus infections.

Pylephlebitis and Right-Sided Endocarditis: A Rare Complication of an Intra-abdominal Infection.

Right-sided infective endocarditis is less common than left-sided endocarditis and can be a difficult clinical diagnosis. The presence of intracardiac devices is a major risk factor. The presentation is less clear than left-sided forms because of the presence of respiratory symptoms and the absence of systemic embolization. Pylephlebitis, or septic thrombosis of the portal vein, is a serious infectious condition that often delays diagnosis. It is a complication of intraabdominal or pelvic infections. Streptococcus gallolyticus (S. gallolyticus) can cause infective endocarditis and is associated with colon neoplasia and hepatobiliary disease. In this case report, we describe the case of a 76-year-old male with a history of rectal adenocarcinoma who presented with different episodes of fever of unknown origin (FUO), one of which occurred after pacemaker implantation. Ultimately, he was diagnosed with S. gallolyticus-mediated tricuspid valve endocarditis with underlying pylephlebitis. Investigations did not show evidence of pacemaker lead endocarditis.

Streptococcus gallolyticus Subspecies (subsp.) pasteurianus Meningitis in a 7-week-old Boy.

Meningitis caused by Streptococcus gallolyticus subspecies (subsp.) pasteurianus is a rare complication with 14 cases reported in literature worldwide between 2003-2023, with the majority of the cases occurring before 4 weeks of life and with preceding symptoms. This is a case report of an infection without any preceding symptoms. A previously healthy 7-week-old boy presented to the hospital with a fever for 1 day. Blood and cerebrospinal fluid cultures ultimately grew Streptococcus gallolyticus subsp. pasteurianus. The magnetic resonance imaging was consistent with meningitis. The boy received 21 days of intravenous antibiotics before discharge. At subsequent visits, the boy had no neurological sequelae, normal hearing tests, and appeared to have met all developmental milestones. The older age of infant should not discount the differential diagnosis for meningitis, which may delay further work up such as a lumbar puncture. Group D streptococcus is an uncommon cause of infantile sepsis that can lead to several complications such as meningitis and bacteremia. In this case, the infant's subsequent post-meningitis clinical course has been unremarkable. The history of meningitis poses increased risk for abnormal neurodevelopmental outcome. This case study highlights the importance of keeping meningitis on the differential diagnosis for an infant with fever. If there is a concern for meningitis, further workup should be performed without delay.

Preterm infant with necrotizing enterocolitis and arteritis secondary to streptococcus gallolyticus subspecies pasteurianus.

 Streptococcus gallolyticus subspecies pasteurianus is a subtype of Streptococcus bovis (S. bovis) that has become increasingly recognized as a sepsis-causing pathogen in neonates. It is well documented that S. bovis species have a predilection to both cardiac and gastrointestinal tissue, and in adult populations, isolating these organisms in the bloodstream often triggers further evaluation for co-morbid complications such as colon cancer or endocarditis. However, no such guidance currently exists in neonatal literature. We present a case of a preterm infant with S. gallolyticus subsp. pasteurianus bacteremia presenting as necrotizing enterocolitis (NEC) not previously described in the literature. Furthermore, through a complete diagnostic evaluation, including an echocardiogram, our patient was found to have the rare complication of endocarditis.

Sciatica caused by spinal epidural abscess as the initial clinical presentation of colon cancer: a rare case report and review of literature.

BACKGROUND: Colorectal cancer is one of the most frequently diagnosed forms of cancer, and it is associated with several common symptoms and signs such as rectal bleeding, altered bowel habits, abdominal pain, anemia, and unintentional weight loss. Sciatica, a debilitating condition in which the patient experiences paresthesia and pain in the dermatome of associated lumbosacral nerve roots or sciatic nerve distribution, is not considered one of these. Here we present a case of colorectal cancer manifesting symptoms of sciatica alone. CASE PRESENTATION: A 68-year-old male presented with progressive lower back pain radiating to his left thigh and calf over L5/S1 dermatome. Sciatica was suspected and initially underwent conservative treatment with analgesics. However, the symptoms progressed and MRI revealed an epidural abscess surprisingly. Surgical debridement was performed and pus culture isolated Streptococcus gallolyticus. Based on the strong association of S. gallolyticus with colorectal cancer, the presence of this pathogen prompted further tumor evaluation, even in the absence of the typical symptoms and signs. This investigation ultimately leads to the diagnosis of sigmoid adenocarcinoma. CONCLUSIONS: Although rare, sciatica caused by S. gallolyticus infection of the spinal epidural space may serve as the initial presentation of colorectal cancer. Physicians should be aware of the strong association between S. gallolyticus and colorectal cancer. Based on what we currently know about the condition; a thorough systematic assessment of occult neoplasia for patients with S. gallolyticus infection is recommended.

Clinical and microbiological profile of Viridans group streptococcal bacteraemia; experience from South India.

Background: Viridans Group Streptococci (VGS) are a group of distinct species that can cause bacteraemia and other invasive infections. They are also among the common organisms causing infective endocarditis. Data on the epidemiology and clinical profile of VGS is limited, especially from India. Methods: We conducted an electronic medical record-based retrospective analysis of patients with VGS bacteraemia admitted to our hospital between January 2012 to December 2021. Blood cultures were incubated by BacT/ALERT system and bacterial identification and susceptibility testing were done by using the VITEK 2 microbial identification system. Susceptibility test reporting was as per Clinical and Laboratory Standards Institute (CLSI) guidelines. The incidence, clinical profile, source of bacteraemia, co-morbidities and antimicrobial resistance among VGS bacteraemia were analyzed. Results: VGS were isolated in 219 patients, accounting for 3.2% of positive blood cultures during the period studied. The median age of the patients was 58 years and 69% were males. Diabetes mellitus was the most common co-morbidity (55%) followed by chronic kidney disease and chronic liver disease. Patients with haematological malignancy and neutropenia were few. Intra-abdominal infections were the most common source of infection and was noted in 26%. Infective endocarditis was diagnosed in only 10% of the cases. Streptococcus mitis was the most common species isolated followed by S. gallolyticus and S. sanguinis. 9.58% of the isolates could not be identified up to the species level. Overall penicillin susceptibility was 71% and ceftriaxone susceptibility was 92%, with individual species variation. In-hospital mortality was 19%. Conclusions: VGS are an important cause of bacteraemia and was associated with 19% mortality in our study. High rates of penicillin and ceftriaxone resistance are a reason of concern. Molecular diagnostics like matrix assisted laser desorption ionization-time of flight (MALDI-TOF) identification must be increasingly applied for species identification considering that a substantial number of isolates were not identified to species level.

Neutropenic Enterocolitis in a Metastatic Seminoma Patient With Streptococcus gallolyticus Bacteremia.

Neutropenic enterocolitis (NEC), also referred to as typhlitis, is a condition associated with a high mortality risk and primarily manifests in immunocompromised patients. It is characterized by ulceration, edema, and hemorrhage affecting the bowel wall. The underlying cause of NEC is postulated as an immunocompromised condition that facilitates bacterial infiltration through compromised bowel mucosa. The high mortality rate is attributable to bowel necrosis, culminating in perforation and sepsis. This report describes a case involving a patient with metastatic seminoma who exhibited seizure-like activity, fever, Streptococcus gallolyticus bacteremia, and NEC. The patient underwent treatment involving broad-spectrum antibiotics and filgrastim. The patient's neutropenia resolved leading to discharge on oral antibiotics. The case reported is unique, as it links NEC to Streptococcus gallolyticus and seminoma. Streptococcus gallolyticus has not been previously associated with NEC.

A Rare Case of Meningitis Caused by Streptococcus gallolyticus subsp. pasteurianus in an Immunocompetent Young Adult.

Bacterial meningitis is a life-threatening condition that is mainly caused by Streptococcus pneumoniae and Neisseria meningitis. Although Streptococcus gallolyticus subsp. pasteurianus (Sgp) is also known to cause meningitis, its frequency is quite low, especially in adults. We herein report the first immunocompetent Japanese adult patient (20-year-old woman) with bacterial meningitis caused by Sgp. The patient showed dramatic improvement after antibiotic treatment. Although previous reports have described an association between Sgp infection and an immunosuppressive status, bowel and hepatobiliary diseases, or strongyloidiasis, our case did not demonstrate any of these conditions, suggesting that Sgp can cause meningitis even in young immunocompetent adults.

A Rare Case of Streptococcus pasteurianus Endocarditis Signaling Colon Cancer.

Infective endocarditis (IE) is a life-threatening condition often associated with various complications. A unique subset of IE cases involves the Streptococcus gallolyticus group, which has a well-documented but sometimes poorly understood association with colonic neoplasms. Specifically, colon cancer has a well-established association with IE caused by S. gallolyticus subspecies (spp.) gallolyticus. However, finding colon cancer in cases of IE due to S. gallolyticus spp. pasteurianus is rather unexpected. Herein, we present a rare instance of IE caused by S. gallolyticus spp. pasteurianus in a 62-year-old male, which led to the discovery of an underlying colorectal carcinoma. Considering the overall elevated risk of colon cancer in patients with endocarditis and in patients with S. bovis/S. equinus complex (SBSEC) bacteremia, we decided to proceed to colonoscopy, which revealed adenocarcinoma. The patient was administered a targeted antibiotic regimen and underwent a successful surgical resection, followed by valve replacement surgery. The outcome of this case supports the recommendation of routine colonoscopic evaluation in patients diagnosed with S. gallolyticus bacteremia, including those with subspecies pasteurianus, particularly when there are other associated findings. It strengthens the argument for conducting a colonoscopy in individuals diagnosed with SBSEC endocarditis, while carefully considering the specifics of each clinical situation. Our report highlights the need for heightened clinical vigilance and an integrated approach to treatment in similar cases.

Late-Onset Meningitis in a Preterm Infant Caused by Streptococcus gallolyticus Subsp. Pasteurianus in Saudi Arabia: A Case Report and Literature Review.

This report describes the progression of meningitis in a 24-day-old preterm male infant infected with Streptococcus gallolyticus subsp. pasteurianus (SGSP) and its medical care, pathogen detection, antibiotic treatment, and monitoring, ultimately leading to a positive outcome of successful recovery. Neonatal meningitis (NM) is a serious and potentially life-threatening condition, particularly in immunocompromised preterm infants. This report from Saudi Arabia presents a rare case of late-onset neonatal meningitis caused by SGSP in a preterm male infant. The 24-day-old preterm neonate presented with fever, lethargy, poor feeding, and respiratory distress. SGSP was confirmed by cerebral spinal fluid analysis showing the presence of pleocytosis and a low glucose ratio. Prompt antibiotic therapy with intravenous Ampicillin and Cefotaxime led to decreased pleocytosis, and the infant was discharged after 21 days. This report highlights the importance of vigilance, diagnosis, and management of neonatal infections caused by uncommon pathogens such as SGSP. The rarity of SGSP-caused meningitis emphasizes the need to monitor pregnant women for potential transmission and to implement early diagnostic and management strategies. This case report also encompasses a review of recent globally reported cases of neonatal S. gallolyticus infection, highlighting the distinctiveness of this report as the first of its type in Saudi Arabia.

Streptococcus gallolyticus Subspecies pasteurianus Meningitis in an Infant with Hypothyroidism and Diarrhea.

Streptococcus gallolyticus subspecies pasteurianus, formerly classified as S. bovis biotype II/2 until 2003, is a rare cause of infant meningitis. Over the past 2 decades, only a few individual case reports and limited case series exist in the English-language literature. Moreover, the pathogenesis of S. gallolyticus subsp. pasteurianus meningitis in infants is unclear. Here we report a case of meningitis in a 6-week-old infant with hypothyroidism and preceding diarrhea. In this case, S. gallolyticus was cultured from cerebrospinal fluid, and then S. gallolyticus subspecies pasteurianus was identified by metagenomic next-generation Sequencing. The infant recovered uneventfully after a 4-week antibiotic course with ceftriaxone and vancomycin. Then combined with the literature of S. gallolyticus subsp. pasteurianus meningitis in infants, we discuss the possible etiology.

Improved identification of Streptococcus bovis-Streptococcus equinus-complex species and subspecies by MALDI-TOF MS using a novel library.

OBJECTIVES: To develop an in-house matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) library for improved identification of species and subspecies of the Streptococcus bovis/Streptococcus equinus-complex (SBSEC). METHODS: A total of 236 SBSEC isolates from blood stream infections and culture collections, determined by whole genome sequencing to subspecies level, were grown in brain heart infusion broth. Mass spectra were collected using the Bruker MALDI Biotyper system after ethanol-formic acid extraction. Main spectral profiles from 117 isolates were used to create the "SBSEC-CMRS library." The remaining 119 spectra were used for evaluation of Bruker MALDI Biotyper (MBT) Compass Library Revision K (2022) and the SBSEC-CMRS library. RESULTS: The Bruker library correctly identified species and subspecies in 72 of 119 (61 %) isolates, while the SBSEC-CMRS library identified 116 of 119 (97 %), using a cutoff score of ≥2.0. CONCLUSIONS: The SBSEC-CMRS library showed sufficient diagnostic accuracy, and can be implemented in clinical practice for SBSEC species and subspecies identification.

Isolation, characterization, and experimental infection of Streptococcus gallolyticus subspecies pasteurianus from commercial turkeys with acute septicemia: a pilot study.

Streptococcus gallolyticus (SG) is a Gram-positive cocci found as commensal gut flora in animals and humans. SG has emerged as a cause of disease in young poults between 1 and 3 wk of age. SG is associated with septicemia resulting in acute mortality with no premonitory signs in turkeys. Three SG isolates were obtained from clinical field cases of acute septicemia of commercial turkeys and used in three independent experiments. In Experiment 1, embryos were inoculated 25 d of embryogenesis with varying concentrations of SG1, SG2, or SG3. In Experiment 2, day of hatch, poults were inoculated with varying concentrations using different routes of administration of SG1, SG2, or SG3. In Experiment 3, day of hatch, poults were inoculated with only isolate SG1 using different paths. Poults were randomly selected for necropsy on d 8 and d 15 and sampled to collect spleen, heart, and liver for SG on d 21, the remaining poults were necropsied and cultured. Samples were plated on Columbia nalidixic acid and colistin agar (CNA) (40°C, 18-24 h). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) confirmed suspect colonies. Data were analyzed using the chi-square test of independence, testing all possible combinations to determine significance (P < 0.05). Weight data were subjected to ANOVA using JMP with significance (P < 0.05). No differences were found in BW or BWG on d 0, 8, 15, or 22. Splenomegaly, focal heart necrosis, and pericarditis were observed in all groups in experiments 1 through 3. In Experiment 3, only airsacculitis was observed in a negative control in separate isolation (P > 0.05). On d 21 of Experiment 3, increased (P < 0.05) recovery of SG from spleens were observed in co-housed negative controls, as well as poults challenged by oral gavage (P > 0.05 for d 7 and d 14). These results confirm numerous previous studies indicating that SG subsp. pasteurianus is a primary infectious microorganism that causes septicemia in young poults.

Characterization of TelE, a T7SS LXG Effector Exhibiting a Conserved C-Terminal Glycine Zipper Motif Required for Toxicity.

Streptococcus gallolyticus subsp. gallolyticus (SGG) is an opportunistic bacterial pathogen strongly associated with colorectal cancer. Here, through comparative genomics analysis, we demonstrated that the genetic locus encoding the type VIIb secretion system (T7SSb) machinery is uniquely present in SGG in two different arrangements. SGG UCN34 carrying the most prevalent T7SSb genetic arrangement was chosen as the reference strain. To identify the effectors secreted by this secretion system, we inactivated the essC gene encoding the motor of this machinery. A comparison of the proteins secreted by UCN34 wild type and its isogenic ΔessC mutant revealed six T7SSb effector proteins, including the expected WXG effector EsxA and three LXG-containing proteins. In this work, we characterized an LXG-family toxin named herein TelE promoting the loss of membrane integrity. Seven homologs of TelE harboring a conserved glycine zipper motif at the C terminus were identified in different SGG isolates. Scanning mutagenesis of this motif showed that the glycine residue at position 470 was crucial for TelE membrane destabilization activity. TelE activity was antagonized by a small protein TipE belonging to the DUF5085 family. Overall, we report herein a unique SGG T7SSb effector exhibiting a toxic activity against nonimmune bacteria. IMPORTANCE In this study, 38 clinical isolates of Streptococcus gallolyticus subsp. gallolyticus (SGG) were sequenced and a genetic locus encoding the type VIIb secretion system (T7SSb) was found conserved and absent from 16 genomes of the closely related S. gallolyticus subsp. pasteurianus (SGP). The T7SSb is a bona fide pathogenicity island. Here, we report that the model organism SGG strain UCN34 secretes six T7SSb effectors. One of the six effectors named TelE displayed a strong toxicity when overexpressed in Escherichia coli. Our results indicate that TelE is probably a pore-forming toxin whose activity can be antagonized by a specific immunity protein named TipE. Overall, we report a unique toxin-immunity protein pair and our data expand the range of effectors secreted through T7SSb.

Association of Antibody Responses to Fusobacterium nucleatum and Streptococcus gallolyticus Proteins with Colorectal Adenoma and Colorectal Cancer.

BACKGROUND: Streptococcus gallolyticus subspecies gallolyticus (SGG) and Fusobacterium (F.) nucleatum have been implicated in colorectal carcinogenesis. Here, the association of immune responses to bacterial exposure with advancing stages of colorectal neoplasia was assessed by multiplex serology. METHODS: Immunoglobulin (Ig) A and G antibody responses to eleven proteins each of F. nucleatum and SGG were measured in plasma of controls (n = 100) and patients with colorectal cancer (CRC, n = 25), advanced adenoma (n = 82), or small polyps (n = 85). Multivariable logistic regression was used to evaluate the association of bacterial sero-positivity with colorectal neoplasia. In a cohort subset with matched data (n = 45), F. nucleatum sero-positivity was correlated with bacterial abundance in both neoplastic and matched normal tissue. RESULTS: IgG sero-positivity to Fn1426 of F. nucleatum was associated with an increased CRC risk (OR = 4.84; 95% CI 1.46-16.0), while IgA sero-positivity to any SGG protein or specifically Gallo0272 and Gallo1675 alone was associated with increased advanced adenoma occurrence (OR = 2.02, 95% CI 1.10-3.71; OR = 2.67, 95% CI 1.10-6.46; and OR = 6.17, 95% CI 1.61-23.5, respectively). Only F. nucleatum abundance in the normal mucosa positively correlated with the IgA response to the Fn1426 antigen (Correlation coefficient (r) = 0.38, p < 0.01). CONCLUSION: Antibody responses to SGG and F. nucleatum were associated with occurrence of colorectal adenomas and CRC, respectively. Further studies are needed to clarify the role these microbes or the immune response to their antigens may have in colorectal carcinogenesis stages.

Streptococcus gallolyticus infection: A neglected marker for colorectal cancer?

BACKGROUND AND STUDY AIMS: Colorectal cancer (CRC) is the second most common cancer in Malaysia and mostly detected at advanced stages due to lack of awareness of CRC symptoms and signs. CRC pathogenesis is multifactorial, and there is ambiguous evidence on association of Streptococcus gallolyticus infection with CRC that needs further attention. Thus, a case-control study was conducted to determine whether S. gallolyticus infection is a predictor for CRC occurrence among patients attending Sultan Ahmad Shah Medical Centre@IIUM (SASMEC@IIUM). PATIENTS AND METHODS: A total of 33 stool samples from patients diagnosed with CRC and 80 from patients without CRC attending surgical clinic of SASMEC@IIUM were collected and analyzed with iFOBT test and PCR assay to detect S. gallolyticus. RESULTS: In this study, the proportion of S. gallolyticus infection was higher among patients with CRC (48.5%) compared with the control group (20%). Univariate analysis shows that occult blood in stool, S. gallolyticus infection and family history were significantly associated with the development of CRC (P < 0.05). Using the multivariate logistic regression model, positive stool PCR for S. gallolyticus had the lowest relative standard error and almost five times the odds of developing CRC after adjusting other factors (adjusted odds ratio = 4.7, 95% confidence interval = 1.7-12.6, relative standard error = 59.6%). CONCLUSION: This finding suggests that S. gallolyticus infection was the strongest predictor of CRC's development in our study and potentially serves as a predictive marker for early detection of disease progression.

Endocarditis by Streptococcus pasteurianus.

The diagnosis of infective endocarditis is challenging because it has a variable clinical presentation and nonspecific symptoms and can present in different forms, especially when an unusual etiological agent is involved. We present the case of a female in her 70s admitted to the hospital with a medical history of bicytopenia, severe aortic stenosis, and rheumatoid arthritis. She had several consultations during which she presented with asthenia and general malaise. A septic screen test was performed that would determine that Streptococcus pasteurianus was present in a blood culture (BC), which was not valued. About three months later, she was hospitalized. In the first 24 hours of admission, the septic screen test was repeated and Streptococcus pasteurianus was isolated in BC. Splenic infarctions and transthoracic echocardiography suggested probable endocarditis, which was confirmed with transesophageal echocardiography. She underwent surgical intervention to remove the perivalvular abscess and replace the aortic prosthesis.