metricas
covid
Buscar en
Enfermedades Infecciosas y Microbiología Clínica (English Edition)
Toda la web
Inicio Enfermedades Infecciosas y Microbiología Clínica (English Edition) Infective endocarditis caused by Streptococcus cristatus
Journal Information
Vol. 41. Issue 5.
Pages 314-315 (May 2023)
Share
Share
Download PDF
More article options
Vol. 41. Issue 5.
Pages 314-315 (May 2023)
Scientific letter
Full text access
Infective endocarditis caused by Streptococcus cristatus
Endocarditis infecciosa causada por Streptococcus cristatus
Visits
151
Domingo Fernández Vecillaa,b,
Corresponding author
domingofvec@gmail.com

Corresponding author.
, José Luis Díaz de Tuesta del Arcoa,b
a Servicio de Microbiología y Parasitología, Hospital Universitario de Basurto, OSI Bilbao-Basurto, Bilbao, Vizcaya, Spain
b Biocruces Bizkaia Health Research Institute, Barakaldo, Vizcaya, Spain
This item has received
Article information
Full Text
Bibliography
Download PDF
Statistics
Figures (1)
Additional material (1)
Full Text

A 76-year-old patient presented at our hospital with intermittent fever of up to 40°C lasting three weeks, coinciding with stem cell inoculation in both hips. The patient had required aortic valve replacement six years earlier and, due to liver cirrhosis with hepatocarcinoma in segment 5, had also required partial hepatectomy and cholecystectomy five months earlier. Twenty days before, the patient had a dental filling for which he did not receive antibiotic prophylaxis. On examination, the patient had a fever of 39.1°C with a pansystolic murmur, and a blood test showed 12,900 leukocytes, 90% of which were neutrophils. Suspecting endocarditis, a blood culture was obtained and the patient was admitted for study and antibiotic treatment with vancomycin and cefepime (1 g/12h and 2g/24h intravenously [IV], respectively).

A transthoracic echocardiogram was performed, in which thickened aortic leaflets were observed, and also a transoesophageal echocardiogram, in which no clear images of endocarditis were observed. The blood culture was positive after 20h of incubation, showing Gram-positive cocci in chains in the Gram stain. The blood culture was inoculated on CNA agars (Becton Dickinson, New Jersey, USA), TSA agars with 5% sheep blood (BD™) and chocolate agar. At 24h, growth was observed, with its identification and antibiotic sensitivity provided by means of the SMIC-ID-11 (BD™) panel in the BD Phoenix™ AP system. The strain was identified as Streptococcus cristatus (S. cristatus), which was sensitive to penicillin (MIC ≤0.03mg/l), vancomycin (MIC = 1mg/l), teicoplanin (MIC ≤1mg/l) and clindamycin (MIC ≤0.03mg/l). In a subsequent blood culture, S. cristatus was identified again, changing the antibiotic treatment to ceftriaxone (2g/24h) while waiting to perform CT + PET-CT. After administration of IV contrast and 18-FDG, lesions compatible with small infarcts in the lower pole of the spleen and left kidney were found, as well as increased metabolic activity in the periprosthetic aortic valve, which did not prevent us from ruling out endocarditis (Fig. 1).

Figure 1.

Joint CT and PET-CT study performed following endocarditis protocol after inconclusive result by transoesophageal echocardiogram by administration of intravenous contrast and 18-FDG, with imaging from the cervical region up to and including the pelvis. Hypodense lesions of triangular morphology and new appearance in the lower pole of the spleen and interpolar region of the left kidney, compatible with small infarcts (yellow circles). Focal increase in metabolic activity (yellow line) on the prosthetic aortic valve annulus's anterior region makes it impossible to rule out endocarditis without significant morphological findings.

(0.12MB).

The condition was considered as probable endocarditis (one major criterion and three minor criteria) and the patient completed six weeks of IV treatment. The patient was followed up through outpatient visits, confirming clinical improvement and normality in subsequent echocardiograms. To confirm the identification, the strain was reseeded to sequence the 16S ribosomal RNA gene. A 637bp sequence was obtained that was entered into BLASTR, and was identified as S. cristatus with an identification percentage of 99.37% (see sequencing protocol and sequence in Appendix B: Supplementary material attached).

S. cristatus was isolated for the first time from the human oral cavity, belonging to the mitisgroup.1 A 2014 study showed that S. cristatus, Streptococcus oligofermentans and Streptococcus sinensis are closely related, and a new phylogenetic clade, the “sinensis group”, was proposed to include these three microorganisms.2 The relationship between infections such as endocarditis and dental interventions has been proven, and prophylaxis is recommended in patients with risk factors, such as valve carriers. In addition, poor dental hygiene also seems to be associated with a higher risk of infections by S. cristatus.3 In the case presented here, and in another of those previously reported, the patients had minor dental interventions or a history of poor dental hygiene prior to the infection.4

Only nine clinical cases of infections caused by this microorganism have been described: six cases of infective endocarditis, one of septic arthritis and two of bacteraemia.4-9 At our institution, we have identified another case of endocarditis by sequencing the 16S rRNA gene from a prosthetic valve sample.

Current treatment guidelines recommend, in patients with viridans group streptococcal prosthetic valve endocarditis, six weeks of penicillin (24 million U/24h IV in continuous infusion or 4-6 doses) or ceftriaxone (2g/24h IV or IM), which can be combined with a 2-6 week regimen of gentamicin (3mg/kg every 24h IV or IM). In highly sensitive strains (MIC of penicillin ≤0.12mg/l), as in our case, the combination with gentamicin has not shown higher cure rates compared to monotherapy.10

This case adds more scientific evidence about the ability of S. cristatus to cause serious infections such as bacteraemia or endocarditis, although more studies are needed to explore its virulence.

Funding

No funding was received.

Conflicts of interest

The authors have no conflicts of interest to declare.

References
[1]
P. Handley, A. Coykendall, D. Beighton, J.M. Hardie, R.A. Whiley.
Streptococcus cristatus sp. nov., a viridans streptococcus with tufted fibrils, isolated from the human oral cavity and throat.
Int J Syst Bacteriol., 41 (1991), pp. 543-547
[2]
J.L. Teng, Y. Huang, H. Tse, J.H. Chen, Y. Tang, S.K. Lau, et al.
Phylogenomic and MALDI-TOF MS analysis of Streptococcus sinensis HKU4T reveals a distinct phylogenetic clade in the genus Streptococcus.
Genome Biol Evol., 6 (2014), pp. 2930-2943
[3]
P.B. Lockhart, M.T. Brennan, M. Thornhill, B.S. Michalowicz, J. Noll, F.K. Bahrani-Mougeot, et al.
Poor oral hygiene as a risk factor for infective endocarditis-related bacteremia.
J Am Dent Assoc., 140 (2009), pp. 1238-1244
[4]
Guzman C, Zaclli A, Molinari J. Streptococcus cristatus —an oral bacterium causing a case of mild bacteriemia and possible endocarditis (2021). Medical Student Research Symposium. 83 [consultado 16 Ago 2022]. Disponible en: https://digitalcommons.wayne.edu/som_srs/83
[5]
D. Bele, N. Kojc, M. Perše, A. Černe Čerček, J. Lindič, A. Aleš Rigler, et al.
Diagnostic and treatment challenge of unrecognized subacute bacterial endocarditis associated with ANCA-PR3 positive immunocomplex glomerulonephritis: A case report and literature review.
BMC Nephrol., 21 (2020), pp. 40
[6]
C. Matthys, G. Claeys, G. Verschraegen, G. Wauters, D. Vogelaers, T. de Baere, et al.
Streptococcus cristatus isolated from a resected heart valve and blood cultures: case reports and application of phenotypic and genotypic techniques for identification.
Acta Clin Belg., 61 (2006), pp. 196-200
[7]
J. Isaksson, M. Rasmussen, B. Nilson, L.S. Stadler, S. Kurland, L. Olaison, et al.
Comparison of species identification of endocarditis associated viridans streptococci using rnpB genotyping and 2 MALDI-TOF systems.
Diagn Microbiol Infect Dis., 81 (2015), pp. 240-245
[8]
G. Gupta, M. Chaudhary, A. Khunt, V. Shah, M.M. Shah.
An unreported case of Streptococcus cristatus septic arthritis of wrist in a neonate.
J Clin Orthop Trauma., 11 (2020), pp. 328-331
[9]
J.A. Lieberman, C. Naureckas Li, G.S. Lamb, D.A. Kane, M.K. Stewart, R.A. Mamedov, et al.
Case report: Comparison of plasma metagenomics to bacterial PCR in a case of prosthetic valve endocarditis.
Front Pediatr., 8 (2021), pp. 575674
[10]
L.M. Baddour, W.R. Wilson, A.S. Bayer, V.G. Fowler Jr., I.M. Tleyjeh, M.J. Rybak, et al.
American Heart Association Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease of the Council on Cardiovascular Disease in the Young, Council on Clinical Cardiology, Council on Cardiovascular Surgery and Anesthesia, and Stroke Council. Infective endocarditis in adults: Diagnosis, antimicrobial therapy, and management of complications: a scientific statement for healthcare professionals from the American Heart Association.
Circulation., 132 (2015), pp. 1435-1486
Copyright © 2022. Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica
Article options
es en pt

¿Es usted profesional sanitario apto para prescribir o dispensar medicamentos?

Are you a health professional able to prescribe or dispense drugs?

Você é um profissional de saúde habilitado a prescrever ou dispensar medicamentos

Quizás le interese:
10.1016/j.eimce.2023.05.001
No mostrar más