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Enrique Navas

Publications and source records attributed to Enrique Navas.

18 recordsLinked to original sources
PubMed2006

Periannular complications in infective endocarditis involving prosthetic aortic valves.

The periannular extension of infection in prosthetic valve endocarditis (PVE) is a serious complication of infective endocarditis associated with high mortality. Periannular lesions in PVE occasionally rupture into adjacent cardiac chambers, leading to aortocavitary fistulae and intracardiac shunting. It is unknown whether the prognosis of patients with aortocavitary fistulae is worse than that of those with nonruptured abscesses. The aims of this study were to determine the distinctive clinical characteristics of patients with PVE and either aortocavitary fistulization or nonruptured abscesses. In a retrospective multicenter study of >872 PVE episodes, 150 patients (17%) with periannular complications in PVE in the aortic position were identified (29 with aortocavitary fistulization and 121 with nonruptured abscesses). Early-onset PVE was present in 73 patients (49%). Rates of heart failure (p = 0.09), ventricular septal defect (p <0.01), and third-degree atrioventricular block (p = 0.07) were higher in patients with fistulization. Surgical treatment was undertaken in 128 patients (83%). In-hospital mortality in the overall population was 39%. Multivariate analysis identified heart failure (odds ratio [OR] 3.3, 95% confidence interval [CI] 1.6 to 6.8), renal failure (OR 2.5, 95% CI 1.2 to 5.2), and co-morbidity (OR 2.4, 95% CI 1.1 to 5.1) as independent risk factors for death. Fistulous tract formation was not associated with increased in-hospital mortality (OR 1.6, 95% CI 0.7 to 3.7). The actuarial 5-year survival rate in surgical survivors was 100% in patients with fistulae and 78% in patients with nonruptured abscesses (log-rank p = 0.14). In conclusion, aortocavitary fistulous tract formation in PVE complicated with periannular complications is associated with higher rates of heart failure, ventricular septal defect, and atrioventricular block than nonruptured abscesses. Despite the frequent complications, fistulous tract formation in the current era of infective endocarditis is not an independent risk factor for mortality.

Abscess↗
PubMed2006

Periannular complications in infective endocarditis involving native aortic valves.

The extension of infection in native valve infective endocarditis (IE) from valvular structures to the periannular tissue is incompletely understood. It is unknown, for example, whether the prognosis of patients with aortocavitary fistulae is worse than that of those with nonruptured abscesses. The aims of this study were to determine the distinct clinical characteristics of patients with aortocavitary fistulae and nonruptured abscesses in native valve IE and to evaluate the impact of fistulization on the outcomes of patients with native aortic valve IE complicated with periannular lesions. In a retrospective multicenter study of 2,055 native valve IE episodes, 201 patients (9.8%) with periannular complications in aortic valve IE were identified (46 with aortocavitary fistulization and 155 with nonruptured abscesses). Rates of heart failure (p = 0.07), ventricular septal defect (p <0.001), and third-degree atrioventricular block (p = 0.07) were higher in patients with fistulization. Surgical treatment was undertaken in 172 patients (86%), and in-hospital mortality in the overall population was 29%. Multivariate analysis identified age >60 years (odds ratio [OR] 2.6, 95% confidence interval [CI] 1.3 to 5.2), renal failure (OR 3.0, 95% CI 1.5 to 6.0), and moderate or severe heart failure (OR 2.5, 95% CI 1.2 to 5.2) as independent risk factors for death. There was a trend toward increased in-hospital mortality in patients with aortocavitary fistulae (OR 1.5, 95% CI 0.7 to 3.0). The actuarial 5-year survival rate in surgical survivors was 80% in patients with fistulae and 92% in patients with nonruptured abscesses (log-rank p = 0.6). In conclusion, aortocavitary fistulous tract formation in the setting of native valve IE is associated with higher rates of heart failure, ventricular septal defect, and atrioventricular block than nonruptured abscess. Despite these higher rates of complications, fistulous tract formation in the current era of IE is not an independent risk factor for mortality.

Abscess↗
PubMed2005

Linezolid for the treatment of multidrug-resistant tuberculosis.

OBJECTIVES: In vitro studies have shown good activity of linezolid against Mycobacterium tuberculosis, including multidrug-resistant strains. However, clinical experience with linezolid in tuberculosis is scarce. METHODS: We report our clinical experience with five consecutive patients with multidrug-resistant tuberculosis infection treated with combination regimens that included linezolid. RESULTS: Two patients had multidrug-resistant Mycobacterium bovis infection, with resistance to 12 antituberculous agents (one of them with HIV co-infection and <50 CD4 cells/mm(3)). The other three patients were infected by multidrug-resistant M. tuberculosis strains, with resistance to all first-line drugs and other second-line drugs. All patients received linezolid in combination with thiacetazone, clofazimine or amoxicillin/clavulanate. Susceptibility tests showed linezolid MIC values < or =0.5 mg/L against all tuberculosis strains tested (standard proportion method, Middlebrook agar 7H10). In all cases, tuberculosis cultures from respiratory samples were sterile after 6 weeks of therapy. Three patients have clinical and microbiological cure of tuberculosis with a combination regimen with linezolid (range: 5-24 months). One patient was lost to follow-up at month 5. The remaining patient has completed 11 months of therapy and is still on treatment. Four patients developed anaemia and needed blood transfusions. In two of these patients, the linezolid daily-dose (600 mg twice a day) was successfully reduced to 50% (300 mg twice a day) to decrease toxicity while maintaining efficacy. Peripheral neuropathy (two patients) and pancreatitis (one patient) were other adverse events observed during linezolid treatment. CONCLUSIONS: In our experience, linezolid has been a valid alternative drug in the management of multidrug-resistant tuberculosis. The prolonged use of linezolid is frequently associated with toxicity, mainly anaemia and peripheral neuropathy, that requires special management.

Acetamides↗
PubMed2005

Lipid disorders in antiretroviral-naive patients treated with lopinavir/ritonavir-based HAART: frequency, characterization and risk factors.

OBJECTIVES: The aim of this study was to evaluate the frequency, characteristics and risk factors of lipid changes associated with lopinavir/ritonavir treatment in antiretroviral-naive patients. METHODS: A prospective cohort of 107 antiretroviral-naive HIV-infected patients was followed for 12 months after starting lopinavir/ritonavir-based highly active antiretroviral therapy. RESULTS: At 12 months, percentages of patients with hypercholesterolaemia and hypertriglyceridaemia were 17.4% and 40%, respectively. Mean increases in total cholesterol and triglycerides were 40.7 and 73.3 mg/dL. There was a significant increase in both low-density and high-density (HDL) cholesterol, and no increase in the total cholesterol/HDL ratio (from 4.16 at baseline to 4.49 after 12 months). Baseline cholesterol > 200 mg/dL and triglycerides > 150 mg/dL were independent risk factors for dyslipidaemia, while hepatitis C coinfection appeared to be protective. CONCLUSIONS: Patients with elevated lipid values at baseline have the greatest risk of developing hypercholesterolaemia and hypertriglyceridaemia after starting lopinavir/ritonavir. Antiretroviral-naive patients coinfected with hepatitis C have a low risk of developing hyperlipidaemia after starting lopinavir/ritonavir.

Adult↗
PubMed2005

Analysis of mortality and risk factors associated with native valve endocarditis in drug users: the importance of vegetation size.

BACKGROUND: Native valve endocarditis in drug-user patients had a microbiology, a frequency of involvement of different cardiac valves, and a prognosis that differ from those in non-drug users. A retrospective study of native valve endocarditis cases in intravenous drug users diagnosed from 1985 to 1999 in our institution was performed to analyze the inhospital mortality of drug users with native valve endocarditis and to identify factors predictive of mortality. METHODS: All patients fulfilled the Duke's criteria for definite or probable endocarditis. Analysis of predictors of inhospital mortality was restricted to right-sided infective endocarditis (IE) with definite diagnosis and echocardiographic data. The following variables were analyzed: sex, HIV serostatus, CD4 cell count < 200/mm3, time of IE diagnosis (before 1993 or after 1993), previous valvulopathy, polymicrobial IE, fungal etiology (mixed or alone), neurological complication, arterial emboli, pulmonary emboli, congestive heart failure, vegetation size (VS) > 2 cm, and inhospital cardiac surgery. Logistic regression was used in a multivariate model to identify factors independently associated with mortality. Adjusted odds ratios (OR) and 95% CIs were examined. RESULTS: Four hundred ninety-three cases of IE were diagnosed in this period. Two hundred twenty cases of native valve endocarditis in intravenous drug users were identified. Fourteen cases in this group died (6%). Mean time from diagnosis to death was 18.5 +/- 15 days (range, 3-52). Vegetation size was available in 111 cases. Univariate analysis identified the following variables associated with inhospital mortality in right-sided cases: VS > 2 cm and fungal etiology. In multivariate analysis, the variables associated with mortality that achieved statistical significance were size of vegetation > 2 cm (P = .014, OR 10.2, 95% CI 1.6-78.0) and fungal etiology (P = .009, OR 46.2, 95% CI 2.4-1100.9). CONCLUSIONS: The main prognostic factors of inhospital mortality in right-sided IE in drug users in our series were VS > 2 cm and fungal etiology. The role of early surgery in these patients should be reevaluated.

Adult↗
PubMed2005

Nosocomial endocarditis in a tertiary hospital: an increasing trend in native valve cases.

INTRODUCTION: Changes in the etiology, epidemiology, and outcome of infective endocarditis (IE) have been observed in recent years. Newer invasive therapeutic interventions have increased the risk of bacteremia and nosocomial endocarditis in the population at risk. A retrospective analysis of hospital-acquired IE cases was performed in a tertiary hospital during 1985 to 1999. MATERIAL AND METHODS: Cases included were those classified as "probable" or "definite" by the IE diagnostic criteria of Durack. Nosocomial acquisition was considered if diagnosis was made > 72 h after hospital admission and there was no evidence that IE was present at the time of admission. Patients receiving a diagnosis within 60 days of a previous hospital admission were also classified as nosocomial, when a risk procedure for bacteremia was performed, or when any predisposing factor for IE was present during hospitalization. Early prosthetic valve endocarditis (PVE) cases (< 1 year) were excluded from the analysis. Clinical characteristics, etiology, predisposing cardiac condition, source of infection, and outcome were analyzed. Results were compared with those obtained in community-acquired cases. RESULTS: Of 493 cases of IE diagnosed over 15 years, 38 were considered to be hospital acquired. Twenty-eight cases were native valve endocarditis (NVE) in non-IV drug user patients, and 10 cases were late PVE. Overall, the most frequent microorganisms involved were staphylococci (58%). The main sources of infection were intravascular procedures or catheter-related infections (55%). When nosocomial NVE cases were compared with community-acquired cases, mortality was greater (29% vs 9.7%) in hospital-acquired endocarditis. Analysis of time trends showed an increased rate of nosocomial cases in NVE throughout the years of the study. CONCLUSIONS: In NVE, the number of cases that are hospital acquired has been increasing during the last 15 years. These cases are frequently associated with invasive intravascular procedures or IV catheter-related infections. Most patients have a previous valvulopathy that predisposes to IE. The spectrum of microorganisms involved is different from the community-acquired cases. Also, the outcome of endocarditis is worse in nosocomial NVE patients.

Adolescent↗
PubMed2004

Aorto-cavitary fistulous tract formation in infective endocarditis: clinical and echocardiographic features of 76 cases and risk factors for mortality.

AIMS: To investigate the clinical features, echocardiographic characteristics, management, and prognostic factors of mortality of aorto-cavitary fistulization (ACF) in infective endocarditis (IE). Extension of infection in aortic valve IE beyond valvular structures may result in peri-annular complications with resulting necrosis and rupture, and subsequent development of ACF. Aorto-cavitary communications create intra-cardiac shunts, which may result in further clinical deterioration and haemodynamic instability. METHODS AND RESULTS: In a retrospective multi-centre study over 4681 episodes of IE, a total of 76 patients with ACF [1.6%, confidence interval (CI) 95%: 1.2-2.0%] diagnosed by echocardiography or during surgery were identified. Fistulae were found in 1.8% of cases of native valve IE and in 3.5% of cases of prosthetic valve IE from the general population and in 0.4% of drug abusers. PVE was present in 31 (41%) cases of ACF. Transthoracic and transoesophageal echocardiography detected the fistulous tracts in 53 and 97% of cases, respectively. Peri-annular abscesses were detected in 78% of cases, fistulae originated in similar rates from the three sinuses of Valsalva, and the four cardiac chambers were equally involved in the fistulous tracts. Heart failure (HF) developed in 62% of cases and surgery was performed in 66 (87% CI 95% 77-93%) patients with a mortality of 41% (95% CI 30-53%) in the overall population. Multivariate analysis identified HF (OR 3.4, CI 95% 1.0-11.5), prosthetic IE (OR 4.6, CI 95% 1.4-15.4) and urgent or emergency surgical treatment (OR 4.3, CI 95% 1.3-16.6) as variables significantly associated with an increased risk of death. Major complications during follow-up (death, re-operation, or re-admission for HF) among the five operative survivors with residual fistulae occurred in 20 and 100% of patients at 1 and 2 years, respectively. CONCLUSION: Aorto-cavitary fistulous tract formation is an uncommon but extremely serious complication of IE. In-hospital mortality was exceptionally high despite aggressive management with surgical intervention in the majority of patients. Prosthetic IE, urgent surgery, and the development of HF identify the subgroup of patients with IE and ACF that have significantly increased risk of in-hospital death.

Adolescent↗
PubMed2004

Focal monophasic demyelinating leukoencephalopathy in advanced HIV infection.

A multiple sclerosis (MS)-like illness has been reported in human immunodeficiency virus (HIV)-infected patients, usually in the early stages of HIV infection. We report 3 patients with advanced HIV infection (CD4 lymphocyte count under 200/mm(3)) presenting with monophasic focal leukoencephalopathy, in whom biopsy demonstrated demyelinating lesions compatible with acute MS lesions. In 1 patient, recently started on highly active antiretroviral therapy, MS-like disease could represent an immune reconstitution syndrome. The lesions were reversible in 2 patients, but rapidly fatal in the third patient. These cases show that an MS-like disease may present in advanced HIV infection as focal monophasic leukoencephalopathy with either a reversible or fulminating course, mimicking progressive multifocal leukoencephalopathy.

Adult↗
PubMed2004

The role of liver biopsy in the management of chronic hepatitis C in patients infected with the human immunodeficiency virus.

We evaluated the role of liver biopsy in the management of chronic hepatitis C in HIV-infected persons. Patients included had abnormal alanine transaminase (ALT) levels, detectable HCV RNA, and an interpretable liver biopsy. Demographic, epidemiologic, clinical, laboratory, histological, and therapeutic data were recorded in all patients. We also registered the clinical diagnosis of cirrhosis (previous to biopsy) and whether the biopsy result deferred the decision of initiating therapy. During the 33-month duration of the study, 112 patients were included. The degree of fibrosis in liver biopsies was none or mild (F0 or F1) in 47 patients (42%) and was significant or severe in 65 (58%). Seventeen patients (15%) had histological cirrhosis. By logistic regression analysis, only portal hypertension (odds ratio [95% confidence interval], 5.3 [1.05-25.9], P = 0.04) was independently associated with significant fibrosis. Overall, cirrhosis was predicted before biopsy in 29 patients (26%) by the caregiving physician, but only 8 of these were confirmed histologically. The clinical prediction of cirrhosis before biopsy had a sensitivity of 47%, a specificity of 78%, a positive predictive value of 28%, and a negative predictive value of 89%. Histological findings changed the decision to initiate HCV therapy in 19 patients (17%) because of little or no fibrosis. Liver biopsy is a useful tool in the management of HCV-HIV-coinfected persons. In addition to allowing grading and staging of the disease far better than any other method or combination of methods, it is important for making management decisions for patients coinfected with HCV and HIV.

Adult↗
PubMed2004

High rate of didanosine-related mitochondrial toxicity in HIV/HCV-coinfected patients receiving ribavirin.

BACKGROUND: Nucleoside analogues may induce mitochondrial toxicity, particularly didanosine. Ribavirin increases didanosine exposure, which might be clinically relevant when coadministered in HIV/HCV-coinfected patients. OBJECTIVE: To evaluate, among 89 patients receiving highly active antiretroviral therapy (HAART) and therapy for chronic hepatitis C, clinically relevant mitochondrial toxicity in those treated with concomitant ribavirin and didanosine (n=35, 39%). METHODS: From January 2000 to July 2002 longitudinal analysis of the incidence and clinical course of didanosine-related hyperamylasaemia, pancreatitis, hyperlactataemia/lactic acidosis or neuropathy. Risk factors were evaluated using univariate and multivariate Cox's proportional hazards model. RESULTS: Among 35 patients who received concomitant didanosine (400 mg/day in 86%) and ribavirin (> or = 10 mg/kg/day in 91%), 20 (57%) developed one or more adverse events after a mean of 87 days. Most frequent laboratory abnormalities were hyperamylasaemia (18 patients, 51%) and hyperlactataemia (eight patients, 23%). Acute pancreatitis and symptomatic hyperlactataemia developed in 10 (28%) and six (17%) patients, respectively. Two patients (6%) with pancreatitis and severe lactic acidosis died; the other patients recovered uneventfully despite continuation of anti-HCV therapy in 83% after didanosine withdrawal in 40%. In the Cox's model higher baseline amylase levels (HR: 1.04, 95% CI: 1.02-1.06, P=0.001) and three nucleoside reverse transcriptase inhibitor-based HAART (HR: 5.3, 95% CI: 1.73-16.24, P=0.003) were significantly associated to toxicity. CONCLUSIONS: The coadministration of didanosine and ribavirin should be avoided in HIV/HCV-coinfected patients, due to a high rate of clinically significant toxicity, particularly in triple nucleoside-based HAART. Amylase levels should be strictly monitored, especially if elevated at baseline.

Adult↗
PubMed2003

Neurological complications of varicella-zoster virus in human immunodeficiency virus-infected patients: changes in prevalence and diagnostic utility of polymerase chain reaction in cerebrospinal fluid.

Neurological complications caused by varicella-zoster virus (VZV) were diagnosed in 13 human immunodeficiency virus (HIV)-infected patients in our hospital. There was a favorable influence of highly active antiretroviral therapy (HAART) in the prevalence of these disorders among acquired immunodeficiency syndrome (AIDS) patients: Since 1996, only 1 of 961 AIDS patients had VZV neurological disease, compared to 9 of 1088 patients before that year (P =.02). Polymerase chain reaction (PCR) detected VZV DNA in cerebrospinal from 4 of 5 patients with VZV neurological disease, and from 2 of 130 HIV-infected patients with other neurological diseases (sensitivity 0.8, specificity 0.98 [95% confidence intervals 0.45-1 and 0.96-1, respectively], positive predictive value 0.94).

Adolescent↗
PubMed2001

Risk factors for development of tuberculosis after isoniazid chemoprophylaxis in human immunodeficiency virus-infected patients.

The long-term benefit of isoniazid chemoprophylaxis in human immunodeficiency virus (HIV)-infected patients and risk factors for isoniazid failure were studied in 131 HIV-infected patients who received >9 months of isoniazid preventive therapy. During a median follow-up of 43 months, 8 patients developed tuberculosis (TB) (6%; 0.61 cases per 100 patient-years). Only the persistence of risk factors for exposure to TB was statistically associated with development of disease (relative hazard, 3.17; 95% confidence interval, 1.56-17; P<.001). Our data suggest reinfection as the main cause of TB after isoniazid prophylaxis.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

Higher virological effectiveness of NNRTI-based antiretroviral regimens containing nevirapine or efavirenz compared to a triple NRTI regimen as initial therapy in HIV-1-infected adults.

PURPOSE: To compare outcomes of nonnucleoside reverse transcriptase inhibitors (NNRTIs) nevirapine or efavirenz versus abacavir-based regimens with a backbone of zidovudine and lamivudine as initial therapy of treatment-naive adults with HIV-1 infection in routine clinical care. METHOD: All patients starting their first antiretroviral therapy with any of the studied regimens from January 1999 to December 2002 were included in the analysis. Rates of viral suppression (HIV-RNA below 50 copies/mL) and discontinuation of any component of the regimen were compared at 48 weeks. RESULTS: Fifty-one patients started with one of the two NNRTI-based regimens and 49 started with the triple nucleoside regimen (3-NRTI). After 48 weeks, more patients in the NNRTI regimens (76.5%) than in the 3-NRTI (51.1%) regimen achieved a HIV-1 RNA level below the limit of detection (<1.7 log10 copies/mL; p = .008). Time to change the antiretroviral regimen was shorter with 3-NRTI (median [range]: 234 [139-329] days) than with NNRTI (346 [0-756] days) (p = .0901). More withdrawals related to drug toxicity or intolerance occurred with the 3-NRTI-based regimen. CONCLUSION: In a routine clinical care setting, initial antiretroviral treatment with an NNRTI (nevirapine or efavirenz) plus zidovudine and lamivudine was virologically superior and safer than a 3-NRTI therapy (abacavir with the same NRTI backbone).

Adult↗
PubMedDate not supplied

Differences in durability of treatment with initial PI-based regimens.

The durability of virologic response to antiretroviral therapy is dependent on the potency, tolerability, and adherence level of the regimen. In a prospective, nonrandomized cohort study, we compared the treatment outcome of a nelfinavir-based highly active antiretroviral therapy (HAART) regimen with that of an indinavir-based regimen, over 1 year of routine clinical practice. Information was derived from 134 treatment-naïve HIV-1-infected patients initiated on triple therapy with either nelfinavir (n = 44) or indinavir (n = 90). The proportions of patients achieving a virological response were similar between treatment groups (>1 log(10) reduction in HIV RNA at 3 months in 95% of patients taking nelfinavir and 88% taking indinavir; HIV RNA <50 copies/mL after 1 year in 79% and 69% of patients, respectively). Predicting factors for 1-year virological suppression were initial virological response (p =.02) and adherence >90% (p =.0001). Over 90% adherence was achieved in 70% of patients taking nelfinavir compared with 41% of those taking indinavir (p =.01). The probability of remaining on the initial protease inhibitor (PI) after 12 months was 77% in the nelfinavir group and 66% in the indinavir group, with the median time to changing treatment being 519 days and 462 days, respectively. Gastric intolerance and nephritic colic were the most common reasons for changing therapy in the indinavir group. In the clinical setting, HAART based on initial nelfinavir and indinavir therapy was associated with similarly good virological and immunological suppression at 1 year, however, nelfinavir-based treatment was associated with a longer durability, probably due to a better adherence and tolerance pattern.

Adult↗