Outcomes of neutropenic hemato-oncological patients with viridans group streptococci (VGS) bloodstream infection based on penicillin susceptibility.

Viridans group streptococci (VGS) bloodstream infection (BSI) in neutropenic patients can be a severe complication. A higher prevalence of vancomycin use has been reported due to reduced susceptibility to penicillin. We aimed to assess the impact on mortality of both penicillin minimal inhibitory concentration (MIC) and the use of vancomycin. We conducted a retrospective multicenter study including consecutive neutropenic patients with VGS BSI between 2007 and 2019. Univariable and multivariable analyses were conducted to evaluate risk factors for mortality, including penicillin susceptibility as an independent variable. Non-susceptibility to penicillin was defined as MIC ≥ 0.25. We included 125 neutropenic patients with VGS BSI. Mean age was 53 years and ~ 50% were women. Overall, 30-day mortality rate was 25/125 (20%), and 41 patients (33%) had a VGS isolate non-susceptible to penicillin. In univariable analysis, no significant association was demonstrated between penicillin non-susceptibility and mortality (9/25, 26% vs. 32/100, 32%, p = 0.81). Among patients with a non-susceptible strain, the use of vancomycin was not significantly associated with mortality (empirical, p = 0.103, or definitive therapy, p = 0.491). Factors significantly associated with increased mortality in multivariable analysis included functional status (ECOG > 1, adjusted odds ratio [aOR] 12.53, 95% CI 3.64-43.14; p < 0.0001); allogeneic transplantation (aOR 6.33, 95% CI 1.96-20.46; p = 0.002); and co-pathogen in blood cultures (aOR 3.99, 95% CI 1.34-11.89; p = 0.013). Among neutropenic hemato-oncological patients with VGS BSI, penicillin non-susceptibility and the use of vancomycin were not associated with mortality. Thus, vancomycin should not be used routinely as empirical therapy in neutropenic patients with suspected VGS BSI.

Infective endocarditis: association between origin of causing bacteria and findings during oral infection screening.

BACKGROUND: Oral streptococci represent the causing microorganism for infective endocarditis (IE) in many patients. The impact of oral infections is questioned, and it has been suggested that bacteraemia due to daily routines may play a bigger part in the aetiology of IE. The aim of this study was to examine the association between oral health and infective endocarditis caused by oral bacteria in comparison with bacteria of other origin than the oral cavity. METHODS: A retrospective study was conducted at Haukeland University Hospital from 2006- 2015. All consecutive adult patients admitted to hospital for treatment of IE and subjected to an oral focus screening including orthopantomogram, were included. The clinical, radiological and laboratory characteristics of the patients, collected during oral infectious focus screening, were analysed. Patient survival was calculated using Kaplan-Meier and mortality rates were compared using Cox-regression. RESULTS: A total of 208 patients were included, 77% (n = 161) male patients and 23% (n = 47) female, mean age was 58 years. A total of 67 (32%) had IE caused by viridans streptococci. No statistically significant correlation could be found between signs of oral infection and IE caused by viridans streptococci. The overall mortality at 30 days was 4.3% (95% CI: 1.6-7.0). There was no statistical difference in mortality between IE caused by viridans streptococci or S. aureus (HRR = 1.16, 95% CI: 0.57-2.37, p = 0.680). CONCLUSION: The study indicates that the association between origin of the IE causing bacteria and findings during oral infection screening might be uncertain and may suggest that the benefit of screening and elimination of oral infections in patients admitted with IE might be overestimated. However, the results should be interpreted with caution and further studies are needed before any definite conclusions can be drawn.

Oral mitis group streptococci reduce infectivity of influenza A virus via acidification and H2O2 production.

Members of the mitis group streptococci are the most abundant inhabitants of the oral cavity and dental plaque. Influenza A virus (IAV), the causative agent of influenza, infects the upper respiratory tract, and co-infection with Streptococcus pneumoniae is a major cause of morbidity during influenza epidemics. S. pneumoniae is a member of mitis group streptococci and shares many features with oral mitis group streptococci. In this study, we investigated the effect of viable Streptococcus oralis, a representative member of oral mitis group, on the infectivity of H1N1 IAV. The infectivity of IAV was measured by a plaque assay using Madin-Darby canine kidney cells. When IAV was incubated in growing culture of S. oralis, the IAV titer decreased in a time- and dose-dependent manner and became less than 100-fold, whereas heat-inactivated S. oralis had no effect. Other oral streptococci such as Streptococcus mutans and Streptococcus salivarius also reduced the viral infectivity to a lesser extent compared to S. oralis and Streptococcus gordonii, another member of the oral mitis group. S. oralis produces hydrogen peroxide (H2O2) at a concentration of 1-2 mM, and its mutant deficient in H2O2 production showed a weaker effect on the inactivation of IAV, suggesting that H2O2 contributes to viral inactivation. The contribution of H2O2 was confirmed by an inhibition assay using catalase, an H2O2-decomposing enzyme. These oral streptococci produce short chain fatty acids (SCFA) such as acetic acid as a by-product of sugar metabolism, and we also found that the inactivation of IAV was dependent on the mildly acidic pH (around pH 5.0) of these streptococcal cultures. Although inactivation of IAV in buffers of pH 5.0 was limited, incubation in the same buffer containing 2 mM H2O2 resulted in marked inactivation of IAV, which was similar to the effect of growing S. oralis culture. Taken together, these results reveal that viable S. oralis can inactivate IAV via the production of SCFAs and H2O2. This finding also suggests that the combination of mildly acidic pH and H2O2 at low concentrations could be an effective method to inactivate IAV.

Case Report: Use of Percutaneous Coronary Revascularization to Temporarily Stabilize a Patient With Streptococcus Viridans Bioprosthetic Aortic Valve Endocarditis Resulting in Non-Embolic Left Main Coronary Artery Obstruction.

A patient with a bio-prosthetic aortic valve streptococcus viridans bacterial endocarditis (SBE) presented with acute massive myocardial ischemia caused from a vegetation adherent to and extending from the valve and growing into the left main (LM) and left circumflex coronary (LCX) coronary arteries. Immediate salvage PCI of the LM and LCX was performed with initial stabilization of the patient.

Genetic variability of the helix 54 of the 23S rDNA and its use as a molecular target for identification of species within the viridans group streptococci (VGS).

The aim of the present study is to establish a method, based on sequence analysis of the helix 54 of 23S rRNA gene, to identify clinical relevant strains belonging to viridans group streptococci (VGS). A set of 25 randomly selected clinical isolates of alpha-hemolytic streptococci from upper respiratory tract were characterized by the routine phenotypic methods (API 20 Strep test). Molecular characterization was assessed by genotypic analysis of the nucleotide sequence of the helix 54 of 23S rRNA and Intergenic spacer region 16S23S. Partial sequencing of the gdh gene was used on 10 strains of mitis group. Sequence variations of the helix 54 allowed the identification of strains to group level and even to species level for certain strains within sanguinis and anginosus groups. Infact, species identification was ambiguous for some strains belonged to the salivarius group (of VGS16 to VGS20) and the mitis group (of VGS1 to VGS14). These results are almost similar to those obtained by sequencing the 16S23S intergenic region. Thus, we use the gdh gene sequencing for the identification of strains, not recognized, within the mitis group. The results generated herein indicate that no single methodology can be used to provide an accurate identification to the species level of all VGS, although nucleotide sequence analysis of the helix 54 of 23S rRNA gene proved to be a reliable method for the identification of VGS to the group level and even to the species level within sanguinis and anginosus groups.

Infecciones por estreptococos del grupo S. anginosus en pediatría / S. anginosus group streptococcal infections in children

Los estreptococos del grupo Streptococcus anginosus (EGA), también llamados "Streptococcus milleri", fueron reconocidos como parte de los estreptococos del grupo viridans (EGV) desde principios del siglo XX. Su rol como patógenos humanos, sin embargo comenzó a destacarse recién en la década de 1970. En esta actualización se describen aspectos microbiológicos y clínicos de los EGA. Los métodos fenotípicos de identificacón e incluso algunos genotípicos carecen de precisión para reconocer las tres especies del grupo (Streptococcus anginosus, Streptococcus constellatus y Streptococcus intermedius) e incluso pueden fallar en su clasificación a nivel de grupo. La mayoría de ellos son sensibles a los antibióticos beta-lactámicos pero son considerables los porcentajes de resistencia a macrólidos, lincosamidas y tetraciclinas. Los EGA son colonizantes habituales de las mucosas orofaríngea, intestinal y genitourinaria, pero, cada vez más frecuentemente, son reconocidos como patógenos humanos. Es ampliamente conocida su capacidad de formar abscesos en órganos sólidos, especialmente abscesos cerebrales, pulmonares y hepáticos. También producen sinusitis, empiemas y colecciones en piel y tejidos blandos, hueso, articulaciones, etc. Se han encontrado asociados con exacerbaciones pulmonares en pacientes con fibrosis quística y con enfermedad pulmonar obstructiva crónica. Producen también infecciones posteriores a mordeduras humanas, infecciones diseminadas, bacteriemia sin foco aparente y, en menor medida, endocarditis infecciosa (AU)

Streptococci from the Streptococcus anginosus group (SAG), also termed "Streptococcus milleri", were recognized as members of the viridans group streptococci (VGS) in the early 20th century. Nevertheless, their role as human pathogens only became evident in the 1970s. In this update, microbiological and clinical aspects of the SAG are described. Phenotypic and even some genotypic identification methods lack accuracy in recognizing the three species of the group (Streptococcus anginosus, Streptococcus constellatus, and Streptococcus intermedius) and may fail to classify them at the group level. Most of them are sensitive to beta-lactam antibiotics but rates of resistance to macrolides, lincosamides, and tetracyclines are significant. SAGs are common colonizers of the oropharyngeal, intestinal, and genitourinary mucosa, but are increasingly recognized as human pathogens. Their ability to form abscesses in solid organs, especially brain, lung and liver, is widely known. They may produce sinusitis, empyemas, and collections in skin and soft tissues, bone, joints, etc. They have also been associated with pulmonary exacerbations in patients with cystic fibrosis and chronic obstructive pulmonary disease. In addition, they may cause infections following human bites, disseminated infections, bacteremia without apparent focus, and, to a lesser extent, infective endocarditis (AU)

Clinical characteristics and outcome of infective endocarditis due to Abiotrophia and Granulicatella compared to Viridans group streptococci.

OBJECTIVE: To describe the clinical characteristics and outcome of Abiotrophia and Granulicatella infective endocarditis and compare them with Viridans group streptococci infective endocarditis. METHODS: All patients in the International Collaboration on Endocarditis (ICE) - prospective cohort study (PCS) and the ICE-PLUS cohort were included (n = 8112). Data from patients with definitive or possible IE due to Abiotrophia species, Granulicatella species and Viridans group streptococci was analyzed. A propensity score (PS) analysis comparing the ABI/GRA-IE and VGS-IE groups according to a 1:2 ratio was performed. RESULTS: Forty-eight (0.64%) cases of ABI/GRA-IE and 1,292 (17.2%) VGS-IE were included in the analysis. The median age of patients with ABI/GRA-IE was lower than VGS-IE (48.1 years vs. 57.9 years; p = 0.001). Clinical features and the rate of in-hospital surgery was similar between ABI/GRA-IE and VGS-IE (52.1% vs. 45.4%; p = 0.366). Unadjusted in-hospital death was lower in ABI/GRA-IE than VGS-IE (2.1% vs. 8.8%; p = 0.003), and cumulative six-month mortality was lower in ABI/GRA-IE than VGS-IE (2.1% vs. 11.9%; p<0.001). After PS analysis, in-hospital mortality was similar in both groups, but six-month mortality was lower in the ABI/GRA IE group (2.1% vs. 10.4%; p = 0.029). CONCLUSIONS: Patients with ABI/GRA-IE were younger, had similar clinical features and rates of surgery and better prognosis than VGS-IE.

Pediatric AML patients with acute-onset cardiomyopathy in the setting of Streptococcus viridans bacteremia after anthracyclines.

We reviewed three very similar cases of acute-onset heart failure in children with acute myeloid leukemia who received anthracyclines during their treatment. All three children were diagnosed with recent Streptococcus viridans bacteremia and had persistent tachycardia prior to acute-onset heart failure with near-complete resolution within weeks. We hypothesize their heart failure was secondary to sepsis-induced cardiomyopathy with anthracycline-induced cardiac myocyte damage as a predisposing factor. We suggest prophylaxis and methods of early detection to prevent and better treat acute heart failure in pediatric oncology patients receiving anthracyclines.

16S rRNA is a valuable tool in finding bacterial aetiology of community-acquired pleural empyema-a population-based observational study in South Sweden.

BACKGROUND: The incidence of community-acquired pleural empyema is increasing. Knowledge of the bacterial aetiology is important in order to base recommendations on empirical antimicrobial treatment. The primary aim of the present study was to describe the bacterial aetiology of adult patients with culture proven and/or 16S rRNA-positive community-acquired pleural infection. METHODS: We performed a retrospective, population-based observational cohort study in Skåne County, south of Sweden. We included all patients with pleural samples obtained between 1st of January 2011 to 31st of December 2017 in Skåne, south of Sweden, with a positive culture and/or 16S rRNA result. Exclusion criteria were patients with culture-negative and/or 16S rRNA-negative pleural samples, age < 18 years, pleural empyema caused by trauma or iatrogenesis, pleural infection caused by tuberculosis or fungi, simultaneous lung- or abscess of the abdomen and bacterial species considered to be contaminants. RESULTS: A total of 291 patients were included in the study, of which 63% were men and the median age was 69 years. The dominating bacterial aetiology was viridans streptococci (36%), followed by Streptococcus pneumoniae (14%) and anaerobic bacteria (12%). 16S rRNA added information of bacterial aetiology in addition to standard culturing methods in 63% of the patients. CONCLUSION: We found that the aetiology of adult patients with culture proven and/or 16S rRNA-positive community-acquired pleural empyema is dominated by viridans streptococci, S. pneumoniae and anaerobic bacteria. Our study shows that 16S rRNA is a valuable tool in finding the bacterial aetiology of community-acquired pleural empyema.

Findings of prosthetic valve endocarditis in the balloon-expandable trans-catheter aortic valve: review of the literature and tips of management.

Prosthetic valve endocarditis after transcatheter aortic valve implantation (TAVI) is a rare complication associated with a high mortality rate. Nonetheless, the rapid expansion of TAVI in recent years has proportionally increased the number of patients exposed to the risk of developing transcatheter valve infection. A 71-year-old female with recent history of TAVI was diagnosed with prosthetic valve obstruction secondary to endocarditis. The characteristics of clinical presentation of endocarditis in the balloon-expandable transcatheter valve and the intra-operative findings are discussed with a review of the literature and tips of management.

Identification of Streptococcus pseudopneumoniae and other mitis group streptococci using matrix assisted laser desorption/ionization - time of flight mass spectrometry.

This study evaluated the ability of the MALDI-ToF MS from Bruker Daltonics to identify clinical Mitis-Group-Streptococcus isolates with a focus on Streptococcus pseudopneumoniae. The results were analyzed using the standard log(score) and the previously published list(score). Importantly, using the log(score) no misidentifications occurred and 27 of 29 (93%) S. pneumoniae and 27 of 30 (90%) S. oralis strains were identified, but only 1 of 31 (3%) S. pseudopneumoniae and 1 of 13 (8%) S. mitis strains were identified. However, our results show that 30 of 31 S. pseudopneumoniae strains had a S. pseudopneumoniae Main Spectral Profiles within the 3 best matches. Using the list(score) all S. oralis and S. pneumoniae strains were identified correctly, but list(score) misidentified 10 S. pseudopneumoniae and 5 S. mitis. We propose to use the log(score) for identification of S. pneumoniae, S. pseudopneumoniae, S. mitis and S. oralis, but for some strains additional testing may be needed.

Multicenter Study of Endocarditis After Transcatheter Pulmonary Valve Replacement.

BACKGROUND: Endocarditis has emerged as one of the most impactful adverse events after transcatheter pulmonary valve replacement (TPVR), but there is limited information about risk factors for and outcomes of this complication. OBJECTIVES: The purpose of this study was to evaluate risk factors for and outcomes of endocarditis in a large multicenter cohort. METHODS: The authors established an international registry focused on characterizing endocarditis after TPVR, including the incidence, risk factors, characteristics, and outcomes. RESULTS: Investigators submitted data for 2,476 patients who underwent TPVR between July 2005 and March 2020 and were followed for 8,475 patient-years. In total, 182 patients were diagnosed with endocarditis a median of 2.7 years after TPVR, for a cumulative incidence of 9.5% (95% CI: 7.9%-11.1%) at 5 years and 16.9% (95% CI: 14.2%-19.8%) at 8 years (accounting for competing risks: death, heart transplant, and explant) and an annualized incidence of 2.2 per 100 patient-years. Staphylococcus aureus and Viridans group Streptococcus species together accounted for 56% of cases. Multivariable analysis confirmed that younger age, a previous history of endocarditis, and a higher residual gradient were risk factors for endocarditis, but transcatheter pulmonary valve type was not. Overall, right ventricular outflow tract (RVOT) reintervention was less often to treat endocarditis than for other reasons, but valve explant was more often caused by endocarditis. Endocarditis was severe in 44% of patients, and 12 patients (6.6%) died, nearly all of whom were infected with Staphylococcus aureus. CONCLUSIONS: The incidence of endocarditis in this multicenter registry was constant over time and consistent with prior smaller studies. The findings of this study, along with ongoing efforts to understand and mitigate risk, will be critical to improve the lifetime management of patients with heart disease involving the RVOT. Although endocarditis can be a serious adverse outcome, TPVR remains an important tool in the management of RVOT dysfunction.

Infective Endocarditis-Associated Purpura and Glomerulonephritis Mimicking IgA Vasculitis: A Diagnostic Pitfall.

BACKGROUND: Purpura and glomerulonephritis are typical presentations in IgA vasculitis. Infective endocarditis mimicking IgA vasculitis by presenting with glomerulonephritis and purpura is rarely reported. METHODS: We searched for cases with infective endocarditis-associated purpura and glomerulonephritis in a tertiary hospital in China and retrospectively reviewed their clinicopathological features. Differential diagnosis and treatment in patients with infective endocarditis-associated purpura and glomerulonephritis were discussed. RESULTS: A total of 20 cases with infective endocarditis-associated purpura and glomerulonephritis were identified among 548 cases with infective endocarditis in our center during an 8-year period: 7 of the 20 cases (35%) were initially misdiagnosed as IgA vasculitis and 10 cases (50%) presented with left-sided endocarditis caused by Streptococcus viridans. Fever (100%, 20 out of 20), prior valvular deformities (80%, 16 out of 20), cardiac murmur (95%, 19 out of 20), splenomegaly (84%, 16 out of 19), embolism (55%, 11 out of 20), and hypocomplementemia (76%, 13 out of 17) were present in most patients. Crescents and mesangial hypercellularity with or without endothelial hypercellularity were the primary findings on light microscopy, with C3-dominant deposition on immunofluorescence. But IgA-dominant staining was also observed (40%, 2 out of 5). In patients with rapidly progressive glomerulonephritis, patients with complete recovery of renal function had shorter disease duration and higher ratio (67% vs 20%) of immunosuppressive therapy compared with patients with partial recovery. CONCLUSIONS: Infective endocarditis-associated glomerulonephritis and purpura can closely mimic IgA vasculitis. Differential diagnosis is challenging, particularly when typical presentations of infective endocarditis are absent. In adults with presentations like IgA vasculitis, infective endocarditis should be evaluated through comprehensive clinical and pathological investigations. Immunosuppressive therapy can be considered in patients with severe glomerulonephritis who do not improve after proper anti-infective therapy.

Viridans Group Streptococci in Pediatric Leukemia and Stem Cell Transplant: Review of a Risk-stratified Guideline for Empiric Vancomycin in Febrile Neutropenia.

Viridans group streptococci (VGS) are an important cause of sepsis in immunosuppressed children. We reviewed the effectiveness of risk-stratified addition of vancomycin to empiric febrile neutropenia therapy among 107 children with leukemia or undergoing an allogeneic transplant. Of 19 VGS bacteremia episodes, 78.9% were susceptible to risk-stratified antibiotics including 100% from high-risk patients. All blood cultures were flagged positive within 24 hours.

Prevention of Viridans Group Streptococcal Infective Endocarditis: A Scientific Statement From the American Heart Association.

BACKGROUND: In 2007, the American Heart Association published updated evidence-based guidelines on the recommended use of antibiotic prophylaxis to prevent viridans group streptococcal (VGS) infective endocarditis (IE) in cardiac patients undergoing invasive procedures. The 2007 guidelines significantly scaled back the underlying conditions for which antibiotic prophylaxis was recommended, leaving only 4 categories thought to confer the highest risk of adverse outcome. The purpose of this update is to examine interval evidence of the acceptance and impact of the 2007 recommendations on VGS IE and, if needed, to make revisions based on this evidence. METHODS AND RESULTS: A writing group was formed consisting of experts in prevention and treatment of infective endocarditis including members of the American Dental Association, the Infectious Diseases Society of America, and the American Academy of Pediatrics, in addition to the American Heart Association. MEDLINE database searches were done for English language articles on compliance with the recommendations in the 2007 guidelines and the frequency of and morbidity or mortality from VGS IE after publication of the 2007 guidelines. Overall, there was good general awareness of the 2007 guidelines but variable compliance with recommendations. There was no convincing evidence that VGS IE frequency, morbidity, or mortality has increased since 2007. CONCLUSIONS: On the basis of a review of the available evidence, there are no recommended changes to the 2007 VGS IE prevention guidelines. We continue to recommend VGS IE prophylaxis only for categories of patients at highest risk for adverse outcome while emphasizing the critical role of good oral health and regular access to dental care for all. Randomized controlled studies to determine whether antibiotic prophylaxis is effective against VGS IE are needed to further refine recommendations.

Diagnosing odontogenic sinusitis of endodontic origin: A multidisciplinary literature review.

PURPOSE: Endodontic disease is one of the most common causes of bacterial odontogenic sinusitis (ODS). Diagnosing ODS of endodontic origin involves otolaryngologists confirming sinusitis, and dental specialists confirming endodontic sources. The purpose of this study was to conduct a multidisciplinary literature review to highlight clinical and microbiological features of ODS, and the most optimal diagnostic modalities to confirm endodontic disease. METHODS: An extensive review of both medical and dental literature was performed by rhinologists, endodontists, and an infectious disease specialist. Frequencies of various clinical and microbiological features from ODS studies were collected, and averages were calculated. Different endodontic testing and imaging modalities were also evaluated on their abilities to confirm endodontic disease. RESULTS: ODS patients most often present with unilateral sinonasal symptoms for over 3 months, purulence on nasal endoscopy, and overt dental pathology on computed tomography (CT). Subjective foul smell, and maxillary sinus cultures demonstrating anaerobes and α-streptococci (viridans group) may be more specific to ODS. For endodontic evaluations, cold pulp testing and cone-beam CT imaging are most optimal for confirming pulpal and periapical disease. CONCLUSION: Diagnosing ODS requires collaboration between otolaryngologists and dental specialists. Clinicians should suspect ODS when patients present with unilateral sinonasal symptoms, especially foul smell. Patients will generally have purulent drainage on nasal endoscopy, and both sinus opacification and overt dental pathology on CT. However, some patients will have subtle or absent dental pathology on CT. For suspected endodontic disease, endodontists should be consulted for at least cold pulp testing, and ideally cone-beam CT.

Performance assessment of ASTA MicroIDSys, a new matrix assisted laser desorption ionization-time of flight mass spectrometry system, for identification of viridans group streptococci.

The performance of the ASTA MicroIDSys system (ASTA), a new matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) system, was evaluated for the identification of viridans group streptococci (VGS) and compared with the results obtained with the Bruker Biotyper system (Bruker Daltonics). A total of 106 Streptococcus reference strains belonging to 24 species from the bacterial strain bank was analyzed using the two MALDI-TOF MS systems. Of the 106 reference strains tested, ASTA MicroIDSys and Bruker Biotyper correctly identified 84.9% and 81.1% at the species level, 100% and 97.2% at the group level and 100% and 98.1% at the genus level, respectively. The difference between the two systems was not statistically significant (P = 0.289). Out of 24 species, 13 species were accurately identified to the species level with 100% accurate identification rates with both systems. The accurate identification rates at the species level of ASTA MicroIDSys and Bruker Biotyper were 100% and 87.5% for the S. anginosus group; 78.4% and 73.5% for the S. mitis group; 91.7% and 91.7% for the S. mutans group; and 100% and 100% for the S. salivarius group, respectively. The ASTA MicroIDSys showed an identification performance equivalent to that of the Bruker Biotyper for VGS. Therefore, it would be useful for the identification of VGS strains in clinical microbiology laboratories.

Viridans Group Streptococcus Meningitis in an Immunocompetent Child: A Case Report.

BACKGROUND Viridans group streptococci (VGS) are commensal organisms in humans that are considered contaminants when isolated from culture specimens. However, VGS can be pathogenic when recovered multiple times from blood cultures or when in immunocompromised hosts. VGS are the leading cause of dental abscesses and infective endocarditis in children with underlying congenital heart diseases. They are not commonly involved in meningeal infections, but meningitis due to VGS can be fatal if not treated. The onset is usually preceded by an upper respiratory tract infection or in association with neurological surgical procedures. CASE REPORT Our patient was a 14-month-old girl with no significant past medical history who presented with fevers and irritability for 2 weeks. A full sepsis workup, including blood, urine, and cerebrospinal fluid (CSF) cultures, was obtained. Culture results were notable for the abundant growth of VGS in the CSF. However, brain imaging and echocardiogram were normal, with no evidence of brain abscesses or cardiac vegetations, respectively. The patient had shown marked clinical improvement after receiving 2 weeks of intravenous ceftriaxone, which was selected based on the VGS susceptibility profile. CONCLUSIONS Bacterial meningitis is one of the most burdensome infectious diseases worldwide, despite improvements in diagnostic methods, management, and national immunization programs. Clinicians should consider VGS in the differential diagnosis of potential infections that can cause meningitis.