Kinetic modelling of colour and turbidity formation in aqueous solutions of sulphamethoxazole degraded by UV/H2O2.

The oxidation of sulphamethoxazole medicine (SMX) has been studied by means of UV/H2O2 conducting at a controlled pH between 2.0 and 12.0 and oxidant ratios of 500 mol H2O2/mol SMX. It is verified that operating at pH = 2.0 the highest rates of SMX degradation (74%) and loss of aromaticity (64%) are obtained. During the process, a strong brown tint and high turbidity are generated in the water depending on the pH, as it affects the chemical speciation of the dissociable compounds. The colour intensity of the water increases from pH = 2.0 (light brown, 3.5 NTU) to a maximum value at pH = 4.0 (dark brown, 42 NTU), when the neutral SMX species is almost 100%. Under these conditions, the formation of carboxylic acids (acetic and oxalic) and nitrate ion are minor. Conducting at higher pH, hue decreases, obtaining at pH = 12.0 a light yellow water (5 NTU) when the anionic SMX predominates. Thus, the maximum formation of nitrate ion occurs under these conditions. A pseudo-first order kinetic modelling is proposed for the loss of aromaticity and colour and turbidity formation in water, where the kinetic parameters are expressed as a function of the applied pH, being the pseudo-first-order rate constants (min-1): karom=0.0005pH2-0.0106pH+0.0707; kcolour=0.0011pH2-0.02pH+0.1125 and kNTU = 0.06 min-1.

The efficacy of suppressive antibiotic treatment in patients managed non-operatively for periprosthetic joint infection and a draining sinus.

Objectives: Patients with prosthetic joint infections (PJIs) not suitable for curative surgery may benefit from suppressive antibiotic therapy (SAT). However, the usefulness of SAT in cases with a draining sinus has never been investigated. Methods: A multicentre, retrospective observational cohort study was performed in which patients with a PJI and a sinus tract were eligible for inclusion if managed conservatively and if sufficient follow-up data were available (i.e. at least 2 years). SAT was defined as a period of >  6 months of oral antibiotic therapy. Results: SAT was initiated in 63 of 72 (87.5 %) included patients. Implant retention during follow-up was the same in patients receiving SAT vs. no SAT (79.4 % vs. 88.9 %; p = 0 .68). In total, 27 % of patients using SAT experienced side effects. In addition, the occurrence of prosthetic loosening in initially fixed implants, the need for surgical debridement, or the occurrence of bacteremia during follow-up could not be fully prevented with the use of SAT, which still occurred in 42 %, 6.3 %, and 3.2 % of cases, respectively. However, the sinus tract tended to close more often (42 % vs. 13 %; p = 0 .14), and a higher resolution of pain was observed (35 % vs. 14 %; p = 0 .22) in patients receiving SAT. Conclusions: SAT is not able to fully prevent complications in patients with a draining sinus. However, it may be beneficial in a subset of patients, particularly in those with pain or the hindrance of a draining sinus. A future prospective study, including a higher number of patients not receiving SAT, is needed.

Blood culture-negative infective endocarditis: a worse outcome? Results from a large multicentre retrospective Spanish cohort study.

BACKGROUND: To assess the impact of blood cultures negative infective endocarditis (BCNIE) on in-hospital mortality. METHODS: Prospective multicentre study with retrospective analysis of a Spanish cohort including adult patients with definite IE. Cardiac implantable devices infection were excluded. Comparisons between blood cultures positive and BCNIE groups were performed to analyse in-hospital mortality. RESULTS: 1001 cases were included of which 83 (8.3%) had BCNIE. Alternative microbiological diagnosis was achieved for 39 (47%) out 83 cases. The most frequent identifications were: Coxiella burnetii (11; 28.2%), Tropheryma whipplei (4; 10.3%), Streptococcus gallolyticus (4;10.3%) and Staphylococcus epidermidis (3; 7.7%). Surgery was performed more frequently in BCNIE group (57.8 vs. 36.9%, p < .001). All-cause in-hospital mortality rate was 26.7% without statistical difference between compared groups. BCNIE was not associated to worse mortality rate in Cox regression model (aHR = 1.37, 95% CI 0.90-2.07, p = .14). Absence of microbiological diagnosis was also not associated to worse in-hospital prognosis (aHR = 1.62, 95% CI 0.99-2.64, p = .06). CONCLUSIONS: In our cohort, BCNIE was not associated to greater in-hospital mortality based in multivariate Cox regression models. The variables most frequently associated with mortality were indicated but not performed surgery (aHR = 2.48, 95% CI 1.73-3.56, p < .001), septic shock (aHR = 2.24, 95% CI 1.68-2.99, p < .001), age over 65 years (aHR = 1.88, 95% CI 1.40-2.52, p < .001) and complicated endocarditis (aHR = 1.79, 95% CI 1.36-2.37, p < .001).

Changes of dissolved oxygen in aqueous solutions of caffeine oxidized by photo-Fenton reagent.

ABSTRACT Formation of oxygen in the caffeine aqueous solutions occurs through self-decomposition reactions of the hydrogen peroxide, used as an oxidant in the photo-Fenton treatment. The total concentration of hydrogen peroxide used in the treatment would be the contribution of the stoichiometric concentration that reacts with the organic matter ([H2O2]0 = 2.0 mM) and the excess of oxidant that decomposes to oxygen, through radical mechanisms, according to a ratio of 0.8164 mmol H2O2 mg-1 O2. When operating at concentrations lower than [H2O2]0 = 2.0 mM, oxygen is not released because there is no excess of oxidant. Moreover, it is verified that the ferrous ion catalyst is oxidized to ferric ion and its subsequent regeneration to ferrous ion. Working at concentrations higher than [H2O2]0 = 2.0 mM, oxygen is released in the water, verifying that the catalyst remains as ferric species, which does not regenerate. The reaction time in which oxygen evolution happpens depends on the concentration of catalyst used in the oxidation, verifying that the highest oxygen generation rates are obtained when applying [Fe]0 = 10.0 mg L-1. Once generated in the water, the maximum concentration of oxygen begins to decrease as the hydrogen peroxide is consumed, until reaching a constant value. The stages of formation and decrease of oxygen are adjusted to zero-order kinetics, estimating the kinetics constants as a function of the catalyst concentration: k f = 29.48 [Fe]0 -1.25 (mg O2 L-1 min-1) and k d = -0.006 [Fe]0 2.0 + 0.244 [Fe]0-3.69 (mg O2 L-1 min-1).

Repeated Pulses of Methyl-Prednisolone in Adults Hospitalized With COVID-19 Pneumonia and Acute Respiratory Distress Syndrome: A Preliminary Before-After Study (CortiCOVID Study).

Introduction: The use of systemic corticosteroids in severely ill patients with coronavirus disease 2019 (COVID-19) is controversial. We aimed to evaluate the efficacy and safety of corticosteroid pulses in patients with COVID-19 pneumonia. Methods: A quasi-experimental study, before and after, was performed in a tertiary referral hospital, including admitted patients showing COVID-19-associated pneumonia. The standard treatment protocol included targeted COVID-19 antiviral therapy from 23rd March 2020, and additionally pulses of methylprednisolone from 30th March 2020. The primary outcome was a composite endpoint combining oro-tracheal intubation (OTI) and death within 7 days. Results: A total of 24 patients were included. Standard of care (SOC) (before intervention) was prescribed in 14 patients, while 10 received SOC plus pulses of methylprednisolone (after intervention). The median age of patients was 64.5 years and 83.3% of the patients were men. The primary composite endpoint occurred in 13 patients (92.9%) who received SOC vs. 2 patients (20%) that received pulses of methylprednisolone (odds ratio, 0.02; 95% confidence interval, 0.001 to 0.25; p = 0.019). Length of hospitalization in survivors was shorter in the corticosteroids group (median, 14.5 [8.5-21.8] days vs. 29 [23-31] days, p = 0.003). There were no differences in the development of infections between both groups. There were 3 deaths, none of them in the corticosteroids group. Conclusions: In patients with severe pneumonia due to COVID-19, the administration of methylprednisolone pulses was associated with a lower rate of OTI and/or death and a shorter hospitalization episode.

Introducción: El uso de corticosteroides sistémicos en pacientes gravemente enfermos por enfermedad coronavírica de 2019 (covid-19) es controvertido. Nuestro objetivo fue evaluar la eficacia y la seguridad de los pulsos de corticoesteroides en los pacientes con neumonía por covid-19. Métodos: Se realizó un ensayo cuasiexperimental, tipo antes y después, en un hospital terciario de referencia que incluyó a pacientes ingresados por neumonía asociada a covid-19. El protocolo de tratamiento estándar incluía un tratamiento antiviral dirigido contra el virus de la covid-19 desde el 23 de marzo de 2020 y añadió pulsos de metilprednisolona desde el 30 de marzo de 2020. El resultado primario fue un criterio combinado compuesto por la intubación orotraqueal y el fallecimiento durante los siguientes siete días. Resultados: Se incluyó un total de 24 pacientes. El protocolo de tratamiento (antes de la intervención) se prescribió en 14 pacientes, mientras que 10 recibieron el protocolo de tratamiento además de los pulsos de metilprednisolona (después de la intervención). La edad media de los pacientes fue de 64,5 años y el 83,3% de los pacientes eran hombres. El resultado combinado primario tuvo lugar en 13 pacientes (92,9%) que recibieron el protocolo de tratamiento frente a 2 pacientes (20%) que recibieron los pulsos de metilprednisolona (odds ratio = 0,02; intervalo de confianza del 95% = 0,001-0,25; p = 0,019). La duración de la hospitalización en los supervivientes fue más corta en el grupo que recibió corticoesteroides (media = 14,5 [8,5-21,8] días frente a 29 [23-31] días, p = 0,003). No hubo diferencias en el desarrollo de infecciones entre ambos grupos. Hubo tres fallecimientos, ninguno de ellos en el grupo que recibió corticoesteroides. Conclusiones: En los pacientes con neumonía grave por covid-19, la administración de pulsos de metilprednisolona se asoció a unas tasas menores de intubación orotraqueal y/o muerte y a episodios de hospitalización más cortos.

Higher MICs (>2 mg/L) Predict 30-Day Mortality in Patients With Lower Respiratory Tract Infections Caused by Multidrug- and Extensively Drug-Resistant Pseudomonas aeruginosa Treated With Ceftolozane/Tazobactam.

BACKGROUND: Ceftolozane/tazobactam (C/T) efficacy and safety in ventilator-associated pneumonia (VAP) is being evaluated at a double dose by several trials. This dosing is based on a pharmacokinetic (PK) model that demonstrated that 3 g q8h achieved ≥90% probability of target attainment (50% ƒT > minimal inhibitory concentration [MIC]) in plasma and epithelial lining fluid against C/T-susceptible P. aeruginosa. The aim of this study was to evaluate the efficacy of different C/T doses in patients with lower respiratory infection (LRI) due to MDR- or XDR-P. aeruginosa considering the C/T MIC. METHODS: This was a multicenter retrospective study of 90 patients with LRI caused by resistant P. aeruginosa who received a standard or high dose (HDo) of C/T. Univariable and multivariable analyses were performed to identify independent predictors of 30-day mortality. RESULTS: The median age (interquartile range) was 65 (51-74) years. Sixty-three (70%) patients had pneumonia, and 27 (30%) had tracheobronchitis. Thirty-three (36.7%) were ventilator-associated respiratory infections. The median C/T MIC (range) was 2 (0.5-4) mg/L. Fifty-four (60%) patients received HDo. Thirty-day mortality was 27.8% (25/90). Mortality was significantly lower in patients with P. aeruginosa strains with MIC ≤2 mg/L and receiving HDo compared with the groups with the same or higher MIC and dosage (16.2% vs 35.8%; P = .041). Multivariate analysis identified septic shock (P < .001), C/T MIC >2 mg/L (P = .045), and increasing Charlson Comorbidity Index (P = .019) as independent predictors of mortality. CONCLUSIONS: The effectiveness of C/T in P. aeruginosa LRI was associated with an MIC ≤2 mg/L, and the lowest mortality was observed when HDo was administered for strains with C/T MIC ≤2 mg/L. HDo was not statistically associated with a better outcome.

Effect of daily consumption of extra virgin olive oil on the lipid profile and microbiota of HIV-infected patients over 50 years of age.

BACKGROUND: Extra virgin olive oil (EVOO) has shown beneficial effects on the lipid profile and inflammatory parameters in general population. Our goal is to analyze these changes together with those of intestinal microbiota in human immunodeficiency virus (HIV)-infected patients over 50 years of age. METHODS: Experimental single arm open study. HIV patients over the age of 50 with undetectable viral load were selected. EVOO was distributed among the patients so that each one consumed 50 g daily for 12 weeks. Lipid profile, C-reactive protein (CRP), and intestinal microbiota composition were analyzed at the beginning and at the end of the intervention. RESULTS: Total cholesterol decreased significantly (5 mg/dL), and a nonsignificant decrease in low-density lipoprotein cholesterol (12 mg/dL), triglycerides (21 mg/dL), and CRP (1.25 mg/dL) was observed. There was a significant increase in alpha diversity after the intervention in men and a decrease in proinflammatory genera such as Dethiosulfovibrionaceae was observed. Differences were also observed in the microbiota of men and women and according to the type of antiretroviral treatment. CONCLUSION: Sustained consumption of 50 g of EVOO in elderly HIV-infected patients might be associated with an improvement in lipid profile and alfa diversity of intestinal microbiota.

Effect of ultrasonic waves on the water turbidity during the oxidation of phenol. Formation of (hydro)peroxo complexes.

Analysis of the kinetics of aqueous phenol oxidation by a sono-Fenton process reveals that the via involving ortho-substituted intermediates prevails: catechol (25.0%), hydroquinone (7.7%) and resorcinol (0.6%). During the oxidation, water rapidly acquires color that reaches its maximum intensity at the maximum concentration of p-benzoquinone. Turbidity formation occurs at a slower rate. Oxidant dosage determines the nature of the intermediates, being trihydroxylated benzenes (pyrogallol, hydroxyhydroquinone) and muconic acid the main precursors causing turbidity. It is found that the concentration of iron species and ultrasonic waves affects the intensity of the turbidity. The pathway of (hydro)peroxo-iron(II) complexes formation is proposed. Operating with 20.0-27.8mgFe2+/kW rates leads to formation of (hydro)peroxo-iron(II) complexes, which induce high turbidity levels. These species would dissociate into ZZ-muconic acid and ferrous ions. Applying relationships around 13.9mgFe2+/kW, the formation of (hydro)peroxo-iron(III) complexes would occur, which could react with carboxylic acids (2,5-dioxo-3-hexenedioic acid). That reaction induces turbidity slower. This is due to the organic substrate reacting with two molecules of the (hydro)peroxo complex. Therefore, it is necessary to accelerate the iron regeneration, intensifying the ultrasonic irradiation. Afterwards, this complex would dissociate into maleic acid and ferric ions.

The role of iron species on the turbidity of oxidized phenol solutions in a photo-Fenton system.

This work aims at establishing the contribution of the iron species to the turbidity of phenol solutions oxidized with photo-Fenton technology. During oxidation, turbidity increases linearly with time till a maximum value, according to a formation rate that shows a dependence of second order with respect to the catalyst concentration. Next, the decrease in turbidity shows the evolution of second-order kinetics, where the kinetics constant is inversely proportional to the dosage of iron, of order 0.7. The concentration of iron species is analysed at the point of maximum turbidity, as a function of the total amount of iron. Then, it is found that using dosages FeT=0-15.0 mg/L, the majority iron species was found to be ferrous ions, indicating that its concentration increases linearly with the dosage of total iron. This result may indicate that the photo-reaction of ferric ion occurs leading to the regeneration of ferrous ion. The results, obtained by operating with initial dosages FeT=15.0 and 25.0 mg/L, suggest that ferrous ion concentration decreases while ferric ion concentration increases in a complementary manner. This fact could be explained as a regeneration cycle of the iron species. The observed turbidity is generated due to the iron being added as a catalyst and the organic matter present in the system. Later, it was found that at the point of maximum turbidity, the concentration of ferrous ions is inversely proportional to the concentration of phenol and its dihydroxylated intermediates.

Influence of early surgical treatment on the prognosis of left-sided infective endocarditis: a multicenter cohort study.

OBJECTIVE: To analyze the influence of early valve operation on mortality in patients with left-sided infective endocarditis (IE). PATIENTS AND METHODS: A multicenter cohort study was carried out between 1990 and 2010. Data from consecutive patients with definite IE and possible left-sided IE were collected. Propensity score matching and adjustment for survivor bias were used to control for confounders. The primary outcome was in-hospital mortality. RESULTS: A total of 1019 patients with a mean age of 61 years (interquartile range, 47-71 years) were included. Early surgical treatment was performed in 417 episodes (40.9%). By propensity score, we matched 316 episodes: 158 who underwent early surgical treatment and 158 who did not (medical treatment group). In-hospital mortality and late mortality were lower in the surgically treated group (26.6% vs 41.8%; absolute risk reduction [ARR], -15.2%; P=.004 and 29.7% vs 46.2%; ARR, -16.5%; P=.002, respectively). Operation was independently associated with a lower risk of in-hospital mortality (odds ratio, 0.42; 95% CI, 0.22-0.79; P=.007). Operation was associated with reduced mortality in patients with paravalvular complications (ARR, -40.5%), severe heart failure (ARR, -32%), and native valve endocarditis (ARR, -17.8%). CONCLUSION: This study supports the benefit of surgical treatment in patients with left-sided IE carried out during the initial phase of hospitalization, especially in patients with moderate or severe heart failure and paravalvular extension of infection.

Changes of turbidity during the phenol oxidation by photo-Fenton treatment.

Turbidity presented by phenol solutions oxidized with Fenton reagent shows the tendency of a first order intermediate kinetics. Thus, turbidity can be considered a representative parameter of the presence of intermediate oxidation species, which are generated along the decomposition of toxic and reluctant contaminants, such as phenol. Moreover, that parameter presents a linear dependence with the catalyst dosage, but is also determined by the initial contaminant load. When analyzing the oxidation mechanism of phenol, it is found that the maximum turbidity occurs when the treatment is carried out at oxidant to phenol molar ratios R = 4.0. These oxidation conditions correspond to the presence of a reaction mixture mainly composed of dihydroxylated rings, precursors of the muconic acid formation. The oxidation via "para" comprises the formation reactions of charge transfer complexes (quinhydrone), between the para-dihydroxylated intermediates (hydroquinone) and the para-substituted quinones (p-benzoquinone), which are quite unstable and reactive species, quickly decomposed into hydroxyhydroquinones. Working with oxidant ratios up to R = 6.0, the maximum observed value of turbidity in the oxidized solutions is kept almost constant. It is found that, in these conditions, the pyrogallol formation is maximal, what is generated through the degradation of ortho-species (catechol and ortho-benzoquinone) and meta-substituted (resorcinol). Operating with ratios over R = 6.0, these intermediates are decomposed into biodegradable acids, generating lower turbidity in the solution. Then, the residual turbidity is a function of the molar ratio of the ferrous ions vs. moles of oxidant utilized in the essays, that lets to estimate the stoichiometric dosage of catalyst as 20 mg/L at pH = 3.0, whereas operating in stoichiometric conditions, R = 14.0, the residual turbidity of water results almost null.

Neurological complications of infective endocarditis: risk factors, outcome, and impact of cardiac surgery: a multicenter observational study.

BACKGROUND: The purpose of this study was to assess the incidence of neurological complications in patients with infective endocarditis, the risk factors for their development, their influence on the clinical outcome, and the impact of cardiac surgery. METHODS AND RESULTS: This was a retrospective analysis of prospectively collected data on a multicenter cohort of 1345 consecutive episodes of left-sided infective endocarditis from 8 centers in Spain. Cox regression models were developed to analyze variables predictive of neurological complications and associated mortality. Three hundred forty patients (25%) experienced such complications: 192 patients (14%) had ischemic events, 86 (6%) had encephalopathy/meningitis, 60 (4%) had hemorrhages, and 2 (1%) had brain abscesses. Independent risk factors associated with all neurological complications were vegetation size ≥3 cm (hazard ratio [HR] 1.91), Staphylococcus aureus as a cause (HR 2.47), mitral valve involvement (HR 1.29), and anticoagulant therapy (HR 1.31). This last variable was particularly related to a greater incidence of hemorrhagic events (HR 2.71). Overall mortality was 30%, and neurological complications had a negative impact on outcome (45% of deaths versus 24% in patients without these complications; P<0.01), although only moderate to severe ischemic stroke (HR 1.63) and brain hemorrhage (HR 1.73) were significantly associated with a poorer prognosis. Antimicrobial treatment reduced (by 33% to 75%) the risk of neurological complications. In patients with hemorrhage, mortality was higher when surgery was performed within 4 weeks of the hemorrhagic event (75% versus 40% in later surgery). CONCLUSIONS: Moderate to severe ischemic stroke and brain hemorrhage were found to have a significant negative impact on the outcome of infective endocarditis. Early appropriate antimicrobial treatment is critical, and transitory discontinuation of anticoagulant therapy should be considered.

Prognostic factors in left-sided endocarditis: results from the Andalusian multicenter cohort.

BACKGROUND: Despite medical advances, mortality in infective endocarditis (IE) is still very high. Previous studies on prognosis in IE have observed conflicting results. The aim of this study was to identify predictors of in-hospital mortality in a large multicenter cohort of left-sided IE. METHODS: An observational multicenter study was conducted from January 1984 to December 2006 in seven hospitals in Andalusia, Spain. Seven hundred and five left-side IE patients were included. The main outcome measure was in-hospital mortality. Several prognostic factors were analysed by univariate tests and then by multilogistic regression model. RESULTS: The overall mortality was 29.5% (25.5% from 1984 to 1995 and 31.9% from 1996 to 2006; Odds Ratio 1.25; 95% Confidence Interval: 0.97-1.60; p = 0.07). In univariate analysis, age, comorbidity, especially chronic liver disease, prosthetic valve, virulent microorganism such as Staphylococcus aureus, Streptococcus agalactiae and fungi, and complications (septic shock, severe heart failure, renal insufficiency, neurologic manifestations and perivalvular extension) were related with higher mortality. Independent factors for mortality in multivariate analysis were: Charlson comorbidity score (OR: 1.2; 95% CI: 1.1-1.3), prosthetic endocarditis (OR: 1.9; CI: 1.2-3.1), Staphylococcus aureus aetiology (OR: 2.1; CI: 1.3-3.5), severe heart failure (OR: 5.4; CI: 3.3-8.8), neurologic manifestations (OR: 1.9; CI: 1.2-2.9), septic shock (OR: 4.2; CI: 2.3-7.7), perivalvular extension (OR: 2.4; CI: 1.3-4.5) and acute renal failure (OR: 1.69; CI: 1.0-2.6). Conversely, Streptococcus viridans group etiology (OR: 0.4; CI: 0.2-0.7) and surgical treatment (OR: 0.5; CI: 0.3-0.8) were protective factors. CONCLUSIONS: Several characteristics of left-sided endocarditis enable selection of a patient group at higher risk of mortality. This group may benefit from more specialised attention in referral centers and should help to identify those patients who might benefit from more aggressive diagnostic and/or therapeutic procedures.

[Left-sided native valve endocarditis by coagulase-negative staphylococci: an emerging disease]. / Endocarditis en válvulas nativas izquierdas por estafilococos coagulasa negativos: una entidad en alza.

OBJECTIVES: To describe the epidemiological, clinical, and prognostic characteristics of patients with left-sided native valve endocarditis (LNVE) caused by coagulase-negative staphylococci (CoNS). PATIENTS AND METHOD: Prospective multicenter study of endocarditis cases reported in the Andalusian Cohort for the Study of Cardiovascular Infections between 1984 and 2005. RESULTS: Among 470 cases of LNVE, 39 (8.3%) were caused by CoNS, a number indicating a 30% increase in the incidence of this infection over the last decade. The mean age of affected patients was 58.32 +/- 15 years and 27 (69.2%) were men. Twenty-one patients (53.8%) had previous known valve disease and half the episodes were considered nosocomial (90% of them from vascular procedures). Median time interval from the onset of symptoms to diagnosis was 14 days (range: 1-120). Renal failure (21 cases, 53.8%), intracardiac damage (11 cases, 28.2%), and central nervous system involvement (10 cases, 25.6%) were the most frequent complications. There were only 3 cases (7.7%) of septic shock. Surgery was performed in 18 patients (46.2%). Nine patients (23.1%) died, overall. Factors associated with higher mortality in the univariate analysis were acute renal failure (P = 0.023), left-sided ventricular failure (P = 0.047), and time prior to diagnosis less than 21 days (P = 0.018). As compared to LNVE due to other microorganisms, the patients were older (P = 0.018), had experienced previous nosocomial manipulation as the source of bacteremia (P < 0.001), and developed acute renal failure more frequently (P = 0.001). Mortality of LNVE due to CoNS was lower than mortality in Staphylococcus aureus infection, but higher than in Streptococcus viridans infection. CONCLUSIONS: Left-sided native valve endocarditis due to CoNS is now increasing because of the ageing of the population. This implies more frequent invasive procedures (mainly vascular) as a consequence of the concomitant disease. Nonetheless, the mortality associated with LNVE due to CoNS does not seem to be greater than infection caused by other pathogens.

Endocarditis en válvulas nativas izquierdas por estafilococos coagulasa negativos: una entidad en alza / Left-sided native valve endocarditis by coagulase-negative staphylococci: an emerging disease

Describir las características epidemiológicas, clínicas y pronósticas de la endocarditis sobre válvula nativa izquierda (EVNI) por estafilococos coagulasa negativos (ECN).PACIENTES Y MÉTODO. Estudio prospectivo multicéntrico delas endocarditis recogidas en la Cohorte Andaluza para el Estudio de las Infecciones Cardiovasculares en los años1984-2005.RESULTADOS. De las 470 EVNI recogidas, 39 (8,3%) fueron causadas por ECN con un aumento del 30% de incidencia en la última década. La edad media fue 58,32 15 años,27 pacientes (69,2%) eran varones y 21 (53,8%) tenían valvulopatía previa. En la mitad de los casos el origen se consideró nosocomial (el 90% tras manipulaciones vasculares). La mediana del intervalo entre la aparición de síntomas y el diagnóstico fue de 14 días (rango: 1-120). Las complicaciones más frecuentes fueron: insuficiencia renal (53,8%), complicaciones cardíacas (28,2%), afectación del sistema nervioso central (25,6%) y shock séptico (7%). La cirugía fue necesaria en 18 pacientes (46,2%) y 9 (23,1%) fallecieron. Los factores que se asociaron con una mortalidad mayor fueron la insuficiencia renal aguda (p 0,023), el fallo ventricular izquierdo (p 0,047) y un tiempo de evolución previo al diagnóstico inferior a 21 días (p 0,018). La EVNI por ECN ocurre en pacientes más ancianos (p 0,018), es con mayor frecuencia de origen nosocomial (p < 0,001) y desarrolla más fracaso renal agudo (p 0,001). La mortalidad es menor que la EVNI producida por Staphylococcus aureus (47,7%), pero mayor que la EVNI por Streptococcus viridans (10,6%).CONCLUSIONES. La EVNI por ECN es una entidad cuya incidencia está aumentando a expensas de una población de edad avanzada, que requiere frecuentemente maniobras diagnósticas o terapéuticas cruentas como consecuencia de sus enfermedades con comitantes. A pesar de ello, la mortalidad no parece ser mayor que en las EVNI causadas por otros patógenos (AU)îes

To describe the epidemiological, clinical, and prognostic characteristics of patients with left-sided native valve endocarditis (LNVE) caused by coagulase-negative staphylococci (CoNS).PATIENTS AND METHOD. Prospective multicenter study of endocarditis cases reported in the Andalusian Cohort for the Study of Cardiovascular Infections between 1984 and 2005.RESULTS. Among 470 cases of LNVE, 39 (8.3%) were caused by CoNS, a number indicating a 30% increase in the incidence of this infection over the last decade. The mean age of affected patients was 58.32 15 years and 27(69.2%) were men. Twenty-one patients (53.8%) had previous known valve disease and half the episodes were considered nosocomial (90% of them from vascular procedures). Median time interval from the onset of symptoms to diagnosis was 14 days (range: 1-120). Renal failure (21 cases, 53.8%), intracardiac damage (11 cases,28.2%), and central nervous system involvement (10 cases,25.6%) were the most frequent complications. There were only 3 cases (7.7%) of septic shock. Surgery was performed in 18 patients (46.2%). Nine patients (23.1%)died, overall. Factors associated with higher mortality in the univariate analysis were acute renal failure (P 0.023), left-sided ventricular failure (P 0.047), and time prior to diagnosis less than 21 days (P 0.018). As compared to LNVE due to other microorganisms, the patients were older (P 0.018), had experienced previous nosocomial manipulation as the source of bacteremia (P < 0.001), and developed acute renal failure more frequently (P 0.001).Mortality of LNVE due to CoNS was lower than mortality in Staphylococcus aureus infection, but higher than in Streptococcus viridans infection. CONCLUSIONS. Left-sided native valve endocarditis dueto CoNS is now increasing because of the ageing of the population. This implies more frequent invasive procedures (mainly vascular) as a consequence ofthe concomitant disease. Nonetheless, the mortality associated with LNVE due to CoNS does not seem to be greater than infection caused by other pathogens (AU)