Publish in this journal
Journal Information
Vol. 75. Issue 3.
Pages 273-275 (March 2022)
Visits
Not available
Vol. 75. Issue 3.
Pages 273-275 (March 2022)
Scientific letter
Full text access
Incidence and mortality of infective endocarditis caused by oral streptococci in the last three decades at a referral center in Spain
Incidencia y mortalidad de la endocarditis infecciosa causada por estreptococos orales en las últimas tres décadas en un centro de referencia en España
Visits
681
Paula Anguitaa,b, Juan C. Castilloa,c, José López-Aguileraa,c, Manuela Herrerab, Manuel Pana,c, Manuel Anguitaa,c,
Corresponding author
manuelanguita@secardiologia.es

Corresponding author:
a Servicio de Cardiología, Hospital Universitario Reina Sofía, Córdoba, Spain
b Facultad de Odontología, Universidad de Sevilla, Sevilla, Spain
c Instituto Maimónides de Investigación Biomédica (IMIBIC), Universidad de Córdoba, Córdoba, Spain
This item has received
Article information
Full Text
Bibliography
Download PDF
Statistics
Tables (2)
Table 1. Number of cases and percentage of endocarditis due to oral streptococci in the total series and by the various types of infective endocarditis during the 3 time periods analyzed
Table 2. Comparison of the characteristics of infective endocarditis caused by oral streptococci in the overall series and in the 3 time periods studied
Show moreShow less
Full Text
To the Editor,

Until 3 to 4 decades ago, infective endocarditis (IE) was considered to be a subacute disease caused by cardiac lesions infected by oral flora microorganisms (mainly Streptococcus viridans). This type of IE has a relatively good prognosis, bearing in mind the severity of this disease.1 However, the clinical and epidemiological profile and prognosis of IE have changed under the impact of recent social and health care changes, such as aging populations, increased numbers of other causal microorganisms (mainly staphylococci and enterococci), and new risk factors (eg, injectable drug use, prosthetic valves, electrical devices, or health care-related bacteremia).2–6 The aim of this study was to analyze the characteristics of oral streptococci IE in a Spanish tertiary hospital, as well as changes in its relative incidence, treatment, and prognosis using a large single-center series collected over the last 30 years in this setting.

We analyzed a cohort of consecutive patients diagnosed with IE and followed up in our hospital between 1990 and 2020 (n=485) to identify cases of IE caused by oral streptococci (S. viridans and nutritionally variant streptococci: Abiotrophia and Granulicatella) and to compare their characteristics during 3 time periods (1990-2000, 2001-2010, and 2011-2020). The study was approved by the ethics committee of our hospital and informed consent was given by all the participants. Of the 485 cases of IE, 346 were native, 59 were early prosthetic, and 80 were late prosthetic. In total, 19.4% (n=94) of the 485 cases were caused by oral streptococci (90 S. viridans, 3 Abiotrophia, and 1 Granulicatella). The most frequent causative organisms were staphylococci (37.9%), followed by enterococci (16.3%). Table 1 shows the number of patients with IE caused by oral streptococci during the 3 time periods and by the various types of IE. Oral streptococci caused 20.1% of native IE and 22.5% of late prosthetic IE, but were very rare in early prosthetic IE. A significant reduction was observed in the proportion of cases caused by these microorganisms, decreasing from 21.7% in the period 1990 to 2000 to 16.7% in the period 2011 to 2020 (P=.045) (table 1). Similar trends were seen regarding native and late prosthetic IE, although without reaching significance (table 1).

Table 1.

Number of cases and percentage of endocarditis due to oral streptococci in the total series and by the various types of infective endocarditis during the 3 time periods analyzed

  Total 1990-2020  1990-2000  2001-2010  2011-2020  P* 
Total, No.  485  138  167  180   
Oral streptococci  94 (19.4)  30 (21.7)  34 (20.3)  30 (16.7)  .045 
Native IE, n  346  94  118  134   
Oral streptococci  73 (20.1)  20 (21.3)  31 (16.7)  22 (16.4)  .160 
Early prosthetic IE, n  59  20  21  18   
Oral streptococci  3 (5.1)  1 (5)  2 (11.1)  .663 
Late prosthetic IE, n  80  24  28  28   
Oral streptococci  18 (22.5)  9 (37.5)  3 (10.7)  6 (21.4)  .089 

IE, infective endocarditis.

Unless otherwise indicated, data are expressed as No. (%).

*

Chi-square test.

Table 2 shows the characteristics of oral streptococcal IE by each time period: no significant differences were observed in age, sex, entry point for bacteremia, most frequent comorbidities, endocarditis site, or relationship with health care. Significant changes were detected over time in the etiology of the underlying heart disease (P=.021), with a reduction in rheumatic etiology and an increase in degenerative etiology and the absence of underlying heart disease. Vegetation size was larger during the more recent periods, although this was probably not due to greater streptococcal aggressiveness, given that the incidence of cardiac complications, persistence of infection, neurologic complications, kidney failure, embolisms, abscesses, and mycotic aneurysms were similar over the study period. All complications involved clinical symptoms, because in our protocol we did not conduct a systematic search for neurologic complications, embolisms, mycotic aneurysms, and so on, in the absence of symptoms or clinical suspicion. Of the 13 abscesses, 12 were periannular and only 1 was distant (splenic). Overall, the incidence of all serious complications, which was 70.2% during the entire period from 1990 to 2020, significantly increased between the periods 1990 to 2000 and 2011 to 2020 (P=.031). The rate of early surgery was similar during the 3 periods (more than 50%), although we observed a decrease in urgent/emergent surgery and a gradual increase in indications for elective surgery (P=.04).

Table 2.

Comparison of the characteristics of infective endocarditis caused by oral streptococci in the overall series and in the 3 time periods studied

  Total series (1990-2020) (No.=94)  1990-2000 (n=30)  2001-2010 (n=34)  2011-2020 (n=30)  Pa 
Age, y  53.3±18.7  54.6±18.1  53.2±18.6  52.8±18.9  .678 
Men  66 (70.2)  22 (73.3)  22 (64.7)  22 (73.3)  .723 
Site of infection          .636 
Mitral  46 (48.9)  15 (50.0)  16 (47.1)  15 (50.0)   
Aortic  48 (51.1)  15 (50.0)  18 (52.9)  15 (50.0)   
Vegetations on TTE  70 (74.5)  17 (56.7)  28 (84.8)  25 (83.3)  .033 
Vegetations on TEE  62 (96.9)  33 (97.1)  29 (96.7)  .857 
Vegetation size, mm  11.7±3.2  9.8±2.7  11.0±3.3  12.6±4.1  .011 
Entry point          .572 
Dental  22 (24.4)  8 (26.7)  7 (20.6)  7 (23.3)   
Respiratory   
Gastrointestinal  3 (3.2)  1 (2.9)  2 (6.7)   
Genitourinary  2 (2.1)  1 (2.9)  1 (3.3)   
Vascular   
Unknown  67 (70.3)  22 (73.3)  25 (73.6)  20 (66.7)   
Underlying heart disease          .021 
Rheumatic  26 (27.6)  15 (50.0)  7 (20.6)  4 (13.3)   
Congenital  21 (22.3)  7 (23.3)  6 (17.6)  8 (26.7)   
Degenerative  27 (28.7)  6 (20.0)  12 (35.4)  9 (30.0)   
Without heart disease  20 (21.4)  2 (6.7)  9 (26.4)  9 (30.0)   
Healthcare-associated IEb  11 (17.5)  2 (6.6)  5 (14.7)  4 (13.3)  .475 
Nosocomial  3 (4.8)  1 (3.3)  1 (2.9)  1 (3.3)   
Nosohusial  8 (12.7)  1 (3.3)  4 (11.8)  3 (10.0)   
Serious complications (any complication)  66 (70.2)  20 (66.7)  21 (61.8)  25 (84.3)  .031 
Heart failure  46 (48.9)  13 (43.3)  18 (52.9)  15 (50.0)  .324 
Uncontrolled infection  10 (10.6)  3 (10.0)  6 (17.6)  1 (3.3)  .426 
Embolism  18 (19.1)  6 (20.0)  5 (14.8)  7 (23.3)  .426 
Neurologic  14 (14.9)  3 (10.0)  6 (17.6)  5 (16.7)  .512 
Kidney failure  3 (3.2)  1 (3.3)  1 (2.9)  1 (3.3)  .853 
Abscess  13 (13.8)  4 (13.3)  4 (11.7)  5 (16.7)  .347 
Mycotic aneurysm  2 (1.8)  1 (3.3)  1 (2.9)  1 (3.3)  .853 
Surgery in the active phase  51 (54.2)  16 (53.3)  18 (52.9)  17 (56.7)  .74 
Urgent/emergent  11 (12.2)  6 (20.0)  3 (8.8)  2 (6.7)  .043 
Elective  40 (42.0)  10 (33.3)  15 (44.1)  15 (50.0)  .043 
Inhospital mortality  14 (14.9)  6 (20.0)  5 (14.7)  3 (10.0)  .045 

IE, infective endocarditis; TEE, transesophageal echocardiogram; TTE, transthoracic echocardiogram.

Data are expressed as No. (%) or mean±standard deviation.

a

Analysis of variance test (ANOVA) for comparison of means for quantitative variables and chi-square test for comparison of proportions (with Yates correction in cases of low frequency) for qualitative variables.

b

Not including history of visits to dentists or oral manipulation.

Early mortality due to oral streptococcal IE significantly decreased from 16.7% in the period 1990 to 2000 to 10% in the period 2011 to 2020 (table 2), despite the increased incidence of severe complications already discussed. This inconsistency may be partly due to the higher rate of elective surgery, which prevents poor disease progression. The results of the multivariable study (stepwise logistic regression) showed an association between streptococcal etiology and a significant reduction in mortality of 26% in the total series (odds ratio=0.74; 95% confidence interval: 0.56-0.92; P=.043).

In conclusion, our analysis of a large single-center series of IE spanning a long time period showed that oral streptococci, mainly S. viridans, continued to cause around 20% of all IE, especially native and late prosthetic endocarditis. Nevertheless, their relative incidence seems to have decreased in recent years, probably due to the increase in cases caused by other microorganisms, such as staphylococci and enterococci. Over the 3 decades analyzed, the clinical and epidemiological characteristics of IE, the incidence of serious complications, and the performance of early surgery have remained unchanged, although in-hospital mortality has recently decreased, reaching just 10% in the last decade.

FUNDING

None declared.

AUTHORS’ CONTRIBUTIONS

All authors contributed equally to the concept, design, data analysis, writing, and revision of the article.

CONFLICTS OF INTEREST

None declared.

References
[1]
J.C. Castillo, M. Anguita, A. Ramírez, et al.
Long-term outcome of infective endocarditis in patients who were not drug addicts: a 10 year study.
Heart., 83 (2000), pp. 525-530
[2]
C. Olmos, I. Vilacosta, C. Fernández-Pérez, et al.
The evolving nature of infective endocarditis in Spain. A population-based study (2003 to 2014).
J Am Coll Cardiol., 70 (2017), pp. 2795-2804
[3]
L. Escolá-Vergé, N. Fernández-Hidalgo, M.N. Larrosa, et al.
Secular trends in the epidemiology and clinical characteristics of Enterococcus faecalis infective endocarditis at a referral center (2007-2018).
Eur J Clin Microbiol Infect Dis., 40 (2021), pp. 1137-1148
[4]
S. Pant, N.J. Patel, A. Deshmukh, et al.
Trends in infective endocarditis incidence, microbiology and valve replacement in the United States from 2000 to 2011.
J Am Coll Cardiol., 65 (2015), pp. 2070-2076
[5]
J. López, A. Revilla, I. Vilacosta, et al.
Age-dependent profile of left-sided infective endocarditis: a 3-center experience.
Circulation., 121 (2010), pp. 892-897
[6]
J. López, A. Revilla, I. Vilacosta, et al.
Definition, clinical profile, microbiological spectrum, and prognostic factors of early-onset prosthetic valve endocarditis.
Eur Heart J., 28 (2007), pp. 760-765
Copyright © 2021. Sociedad Española de Cardiología
Idiomas
Revista Española de Cardiología (English Edition)

Subscribe to our newsletter

View newsletter history
Article options
Tools
es en

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

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