Search PubMed⌕ Search

Biomedical subjects

M Almela

Publications and source records attributed to M Almela.

At least 19 recordsLinked to original sources

Pathogenic significance of methicillin resistance for patients with Staphylococcus aureus bacteremia.

To assess whether methicillin resistance is a microbial characteristic associated with deleterious clinical outcome, we performed a cohort study on 908 consecutive episodes of Staphylococcus aureus bacteremia and a case-control study involving 163 pairs of patients matched for preexisting comorbidities, prognosis of the underlying disease, length of hospitalization, and age. Of 908 bacteremic episodes, 225 (24.8%) were due to methicillin-resistant S. aureus (MRSA). Multivariate analysis did not reveal that methicillin resistance was an independent predictor for mortality when shock, source of bacteremia, presence of an ultimately or rapidly fatal underlying disease, acquisition of the infection in an intensive care unit (ICU), inappropriate empirical therapy, female sex, and age were taken into account. Nonetheless, methicillin resistance was an independent predictor for shock. The case-control study could not confirm that shock was linked to MRSA when prior antimicrobial therapy, inappropriate treatment, ICU residence, and female sex were considered. Our data suggest that cohort studies tend to magnify the relationship of MRSA with clinical markers of microbial pathogenicity and that this effect is a shortcoming of these kind of studies that is caused by inadequate control for underlying diseases.

Adult↗

[Predictive factors of the presence of bacteremia in males with urinary infection].

UNLABELLED: BACKGROUND AND PATIENTS AND METHODS: Possible predictive factors of the presence of bacteremia in 135 males with parenchymatous urinary tract infection (PUI) are studied by means of univariate and multivariate analysis. RESULTS: Thirty percent of the patients had bacteremia. In the multivariate analysis the following factors were significative: duration of symptoms > 5 days, a serum creatinine level > 1.2 mg/dl and duration of symptoms > 5 days. CONCLUSIONS: One third of the males with community acquired PUI have bacteremia. The best predictors of the presence of bacteremia are a serum creatinine level > 1.2 mg/dl and duration of symptoms > 5 days.

Acute Disease↗

Pseudomonas aeruginosa bacteremia in patients infected with human immunodeficiency virus type 1.

A prospective analysis of 43 episodes of Pseudomonas aeruginosa bacteremia in HIV-1-infected subjects was performed and the results compared with the incidence and outcome of Pseudomonas aeruginosa bacteremia in other high-risk patients, such as transplant recipients, leukemia patients, or patients hospitalized in the intensive care unit. The incidence of bacteremia/fungemia as a whole and of gram-negative and Pseudomonas aeruginosa bacteremia in particular was greater in HIV-1-infected subjects than in the unselected general population admitted. In contrast, the incidence of Pseudomonas aeruginosa bacteremia in HIV-1-infected patients did not differ from that in patients with other high-risk conditions. In patients with HIV-1 infection, independent risk factors for presenting Pseudomonas aeruginosa bacteremia were nosocomial origin (OR, 2.7; 95% CI, 1.3-5.7), neutropenia (OR, 2.7; 95% CI, 1.07-6.8), previous treatment with cephalosporins (OR, 3.6; 95% CI, 1.1-11.6), and a CD4+ cell count lower than 50 cells/mm3 (OR, 3.1; 95% CI, 1.7-8.6). Primary bacteremia and pneumonia were the most common forms of presentation. Fourteen (33%) patients died as a consequence of the bacteremia. The presence of severe sepsis (OR, 17.5; 95% CI, 3.2-68) and the institution of inappropriate definitive antibiotic therapy (OR, 2.7; 95% CI, 1.1-13) were independently associated with a poor outcome. One year after the development of bacteremia, only eight (19%) patients remained alive.

AIDS-Related Opportunistic Infections↗

Prospective assessment of the risk of bacteremia in cirrhotic patients undergoing lower intestinal endoscopy.

BACKGROUND: Patients who have prosthetic heart valves, previous history of endocarditis, and surgically constructed systemic-pulmonary shunts or conduits should receive prophylactic antibiotics before colonoscopy. The usefulness of this approach in cirrhotic patients remains unknown. The present study prospectively assesses the incidence of bacteremia in these patients. METHODS: Lower intestinal endoscopy was performed in 58 cirrhotic patients. Two blood samples were obtained from every patient (just before endoscopy and within 5 minutes of withdrawal of the endoscope) and were incubated for 7 days and examined daily for growth of bacteria. Patients were closely monitored for 72 hours after endoscopy to detect the development of infectious complications. RESULTS: Only 6 cultures from 6 patients were positive. Four were obtained post-endoscopy and the remaining 2 before colonoscopy but the corresponding post-endoscopy samples were negative. All organisms recovered were normal skin flora. All patients, including those with positive cultures, remained asymptomatic during the 72 hours after the procedure. CONCLUSIONS: Our findings indicate that lower intestinal endoscopy does not induce bacteremia in cirrhotic patients with or without ascites in the absence of gastrointestinal bleeding and do not support the routine use of prophylactic antibiotics in these patients.

Bacteremia↗

Central venous catheter exchange by guidewire for treatment of catheter-related bacteraemia in patients undergoing BMT or intensive chemotherapy.

Current guidelines for the treatment of catheter-related bacteraemia (CRB) advise against central venous catheter (CVC) exchange because of the potential risk of prolonging infection. However, there are no consistent data proving this recommendation. We evaluated prospectively the usefulness of CVC exchange by guidewire for the treatment of CRB in patients undergoing BMT or intensive chemotherapy. CVC exchange was considered when fever and positive blood cultures persisted after 2 days of adequate antimicrobial therapy and no potential source of bacteraemia other than CVC could be identified. The guidewire exchange was preceded and followed by a slow infusion of adequate antimicrobial therapy. Bacteraemia was confirmed as catheter-related by demonstrating concordance between isolates from the tip and blood cultures by pulsed-field electrophoresis of genomic DNA. This procedure was performed in 19 episodes of bacteraemia during a 1-year period. Fourteen episodes (74%) were catheter-related and 71% of these were due to coagulase-negative staphylococci. Guidewire replacement was accomplished uneventfully 4 days after development of sepsis (range 3-6). In all cases, clinical signs of sepsis disappeared in less than 24 h after replacement. Definitive catheter withdrawal was carried out a median of 16 days (range 3-42) after guidewire exchange; in all cases, the tip culture was negative. We conclude that CVC replacement by guidewire under adequate antimicrobial therapy may be a reasonable option for the treatment of CRB when antimicrobial therapy alone has been unsuccessful.

Adult↗

[Cefixime versus amoxicillin plus netilmicin in the treatment of community-acquired non-complicated acute pyelonephritis].

BACKGROUND: Community-acquired non-complicated acute pyelonephritis (APN) is a frequent, occasionally serious infection (around 20% of the cases are bacteremic) that usually requires hospital admission. The third generation oral cephalosporins which are active against more than 95% of E. coli strains should allow the outpatient management of these patients. OBJECTIVE: To evaluate the bacteriological and clinical efficacy of oral cefixime in comparison to amoxicilin plus netilcilin in the treatment of APN. PATIENTS AND METHODS: Patients older than 18 years affected by APN were included in a fourteen month prospective study. According to a random numbers chart, the patients received cefixime (400 mg/24 h in a single daily dose for 12 days) or amoxicilin (1 g/8 h per os) plus netilmicin (4 mg/kg/24 h in a single intramuscular daily dose) during five days followed by 7 days of an oral treatment chosen according to the susceptibility pattern of isolated microorganism. RESULTS: Sixty-one patients received cefixime and 65 amoxicillin plus retilmicin. There were no significant differences between both groups of patients. Thirty-two patients presented bacteremia (25.4%). The mean (SD) eak and trough concentrations of netilmicin were 11.4 (2.8) mg/l and 0.38 (0.4) mg/l, respectively. Clinical response was favorable in 97% of patients treated with cefixime and in 98% of those treated with amoxicilin plus netilmicin (p = NS). The infection recurred in 10 out of 59 patients (16.9%) in the cefixime arm of the study and in 9 out of 64 patients (14%) treated with amoxicillin plus netilmicin (p = NS). Tolerance to the study drugs was good in both arms of the study, and renal function remained normal. CONCLUSION: Cefixime seems to be an acceptable alternative to the regimens containing an aminopenicillin and an aminoglycoside for the treatment of community-acquired non-complicated APN.

Acute Disease↗

Perinatal listeriosis: a population-based multicenter study in Barcelona, Spain (1990-1996).

The aim off this study was to describe the incidence, epidemiology, clinical presentation, and outcome of perinatal listeriosis for a 7-year period (1990-1996) based on data of an active population-based surveillance project implemented in the city of Barcelona, Spain. There were 30 cases (20.8%) associated with pregnancy (15 pregnant women, 13 neonates, and 2 fetal deaths). The incidence of perinatal listeriosis varied from 4.1 to 0 per 10,000 live births. The proportion of perinatal cases in relation to the total number of cases of listeriosis varied between 0 and 42%. Early-onset neonatal sepsis accounted for 12 of 13 live births. The mean age of infected pregnant women with listeriosis was 30.1+/-2.0 years. Chorioamnionitis was the predominant clinical form (86.7%). Only two mothers had primary bacteremia by L. monocytogenes in the second trimester of pregnancy. Both infants were born healthy, without signs of infection. One of these mothers was infected with the human immunodeficiency virus (HIV). Since January 1994, 12 strains were available for serotyping and phagotyping; 9 belonged to serovar 4b, 2 to serovar 1/2b, and 1 to serovar 1/2a. No outbreaks of L. monocytogenes infection occurred during the study period. The overall neonatal mortality rate was 7.7% among infected live births. All pregnant women were treated with ampicillin and none died. Early antenatal treatment with ampicillin improves neonatal outcome and can result in the birth of healthy babies.

Adult↗

[Yield of blood cultures in relation to the cultured blood volume in Bactec 6A bottles].

BACKGROUND: Concentration of microorganisms in blood is low in bacteremia from extravascular sources. The best yield from blood cultures is achieved by culturing a minimum of 10-20 ml, although in some processing blood culture systems such as Bactec NR-860, smaller volume is used. The objectives of the present study were to establish the frequency in which inadequate small blood volumes are employed for culturing and to analyze the relation between the cultured blood volume in Bactec 6A bottles and the yield achieved. MATERIAL AND METHODS: We weighed 2000 Bactec 6A bottles pertaining to consecutive blood cultures obtained from untreated patients with clinical suspicion of Infection. The cultured blood volume was estimated subtracting the mean empty bottle weight. RESULTS: Microorganisms were recovered from 251 bottles (12.5%). One hundred and thirty one (6.8%) isolates were considered as clinically significant and 115 (5.7%) as contaminant. The inoculated blood volume in both significant (5.532 +/- 1.587 ml) and non-significant (5.471 +/- 1.563 ml) recoveries was superior than that of bottles without microbiologic growth (5.209 +/- 1.575 ml, p = 0.016 and p = 0.06, respectively). A linear positive trend was found between the cultivated blood volume and the rate of recoveries (p = 0.008). Within the range of 1 up to 10 ml, the rate of recoveries increased 2.28% for each additional ml of cultivated blood (r = 0.953, p < 0.0001). Out of the 2,000 weighed bottles 127 (6.3%) contained less than 3 ml of blood and 576 (29%) between 3 and 5 ml. CONCLUSIONS: We have proved that the rate of recoveries from Bactec 6A bottles increased with the volume of cultured blood. In untreated patients, this increase is maintained up to volumes of 7 to 10 ml.

Adult↗

[A study of 30 patients with bacteremia due to Campylobacter spp].

BACKGROUND: To get better knowledge about clinical and bacteriological features in Campylobacter spp. bacteremia. PATIENTS AND METHODS: Over a period of 8 years (1987-1994) we prospectively analyzed underlying diseases, predisposing factors, clinical manifestations, complications and outcome of patients with Campylobacter spp. bacteremia. The study took place in an urban third-level teaching hospital. Antibiogram was tested in all the strains isolated. RESULTS: We identified 30 cases of Campylobacter spp. bacteremia (26 due to C. jejuni and 4 due to C. fetus). Seventy-three percent of the patients were male and the mean age +/- SD of all the patients was 52 +/- 19 years. Ninety percent of patients had some kind of immunodepression related to immunosuppressive therapy or to underlying diseases, especially liver cirrhosis and HIV infection. All patients had fever and 40% complained of intestinal symptoms before bacteremia. Mortality rate in patients with C. jejuni bacteremia was 30.8% (8 patients) during the admission, the death was directly related to bacteremia in 11.5% (3 patients). In all the fatal cases C. jejuni was resistant to empirical antibiotherapy instituted. In contrast, none of the patients with C. fetus bacteremia died. We detected an increasing ciproflaxin resistance in C. jejuni strains during this period which reached to 75% in the last years. Antimicrobial susceptibility to erythromycin and aminoglucosids was kept in all the strains. CONCLUSIONS: Campylobacter spp. bacteremia has a remarkable mortality rate, probably related to immunosuppressive underlying diseases in affective patients. In our institution we detected an increasing fluoroquinolone resistance over the years while susceptibility to erythromycin and aminoglucosids was maintained.

Adult↗

Risk factors for oxacillin/methicillin resistance in coagulase-negative staphylococci.

The clinical variables associated with isolation of oxacillin- and methicillin-resistant, coagulase-negative staphylococci (CNS) from blood cultures of hospitalized patients were studied. One hundred CNS strains (49 oxacillin-susceptible; 51 oxacillin-resistant) isolated consecutively from one of two or more sets of blood cultures were collected. Only two variables were independently associated with recovery of oxacillin/methicillin-resistant strains by a multivariate analysis: length of hospital stay > 10 days (OR 5.2, 95% CI = 1.7-15.7), and administration of antimicrobial agents in the previous 14 days (OR 4.5, 95% CI = 1.7-11.7). Analysis of the antibiotics administered indicated that only beta-lactams were associated with a statistically significant risk of resistance to oxacillin/methicillin (OR of beta-lactams vs no antibiotics = 6.94, 95% CI = 1.9-25.3; OR of non-beta-lactams vs no antibiotics = 2.64, 95% CI = 0.8-8.3). Length of hospital stay (especially > 10 days) and prior administration of antimicrobial agents (mainly beta-lactams) independently predicted the presence of oxacillin/methicillin-resistant CNS in blood cultures.

Cross Infection↗

Epidemiology and outcome of Pseudomonas aeruginosa bacteremia, with special emphasis on the influence of antibiotic treatment. Analysis of 189 episodes.

OBJECTIVE: To evaluate the trend in incidence of Pseudomonas aeruginosa bacteremia, underlying conditions of patients, mortality rate, and factors associated with poor outcome. PATIENTS AND METHODS: Medical charts of 189 consecutive episodes of P aeruginosa bacteremia, detected between January 1, 1991, and December 31, 1994, were prospectively evaluated. Associated risk factors, treatment, and outcome were recorded. RESULTS: Pseudomonas aeruginosa bacteremia represented 5.7% of the total number of bacteremias, 6.9% of nosocomial bacteremias, and 23.6% of nosocomial gram-negative bacteremias. There were 1.5 episodes per 1000 discharges. These numbers were slightly lower than those recorded at our hospital 10 years earlier. Human immunodeficiency virus infection was the most frequent underlying disease (28/189 [15%]). Overall mortality was 18% (34/189). The presence of fatal underlying disease (P < .001), surgery (P = .001), pneumonia (P = .02), and severe sepsis (P < .001) were associated with poor prognosis, the mortality of the patients with these variables being 28%, 28%, 47%, and 62%, respectively. The presence of inappropriate definitive antimicrobial treatment became an independent factor predictive of death (P = .04) only when the subset of patients with intravenous catheter-associated bacteremia was excluded from the analysis. The survival rate was no greater in patients who received 2 or more antibiotics active in vitro against P aeruginosa than in those who received only 1. Neutropenia was not associated with increased mortality. The use of colony-stimulating factors did not affect the outcome of the neutropenic patients. CONCLUSIONS: The rate of P aeruginosa bacteremia is falling slightly at our hospital. The emergence of the human immunodeficiency virus epidemic has had a considerable impact on both epidemiology and mortality. The presence of severe underlying disease, surgery, pneumonia, and, especially, severe sepsis are associated with a poor outcome. With the exclusion of patients with intravenous catheter-associated P aeruginosa bacteremia, the administration of an appropriate antimicrobial therapy is essential to a good outcome. Treatment with 1 active antibiotic seems to be sufficient.

Aged↗

[138 episodes of bacteremia or fungemia in patients with solid organ (renal or hepatic) transplantation].

BACKGROUND: To study the bacteremias and fungemias of the patients with solid organ transplantation (kidney or liver) and analyze the differences according to the type of graft. METHODS: A prospective study included in a control program of bacteremias of a 1000-bed hospital and a follow up study of the infections of the patients who had undergone kidney transplantation (KT) (1985-1991) and liver transplantation (LT) (1988-1991) were carried out. RESULTS: One hundred thirty-one bacteremias and 5 fungemias, 75 in 62 patients with KT out of a total of 568 transplantations (11%) and 63 out of 54 patients with LT out of a total of 185 transplantations (29%) were identified. The prevalence of bacteremia in LT was greater (p < 0.001). The origin was nosocomial in 95% in LT and 70% in KT (p < 0.001). Around 50% of the bacteremias occurred during the first month post LT and KT. The microorganisms isolated were: Staphylococcus sp. (21 in KT and 30 in LT), with greater incidence in LT (p < 0.05); Enterococcus sp. (9 and 5, respectively), enterobacterias (12 and 12, respectively), Pseudomonas sp. (14 and 6, respectively), Candida sp. (2 and 3, respectively) with similar rates in both transplants. The origin of bacteremia was; renal and urinary tract, most frequent in KT (21 and 2 respectively) (p = 0.001). The origin of bacteremia was: renal and urinary tract, most frequent in KT (21 and 2 respectively) (p < 0.001), intraabdominal and biliary tract, most frequent in LT (4 and 14, respectively) (p = 0.007); intravenous catheter, most frequent in LT (16 and 24 respectively) (p < 0.05); lung, most frequent in LT although without statistical significance (3 and 8, respectively), (p = NS), and finally, surgical wound (4 and 1, respectively) (p = NS). Seventeen patients died (14 with LT and 3 with KT). CONCLUSIONS: The incidence of bacteremia and the mortality related, was greater in LT than that observed in KT. The most frequent origin in KT was the kidney and urinary tract and the biliary and intraabdominal organs and the intravenous catheter were most prevalent in liver transplants. Staphylococcus sp was the most frequent germ in both types of transplantation and polymicrobian infection in liver transplants. Gram-negative germs caused higher mortality in liver transplantation.

Bacteremia↗

[Clinico-epidemiologic study of human listeriosis in Barcelona (1990-1991)].

BACKGROUND: The aim of this study was to determine the incidence of human listeriosis in Barcelona in addition to its clinical form of presentation, seasonability, risk groups and evolution. METHODS: A prospective study of the cases of listeriosis registered in the city of Barcelona, Spain (population of 1,643,542 inhabitants) over the period from January 1, 1990 to December 31, 1991 was carried out. RESULTS: Fifty-five cases were reviewed with a global rate of incidence of listeriosis of 9.4 per one million inhabitants per year with predominance being observed in the summer months (39% in 1990, 42% in 1991). Ninety-one percent of the cases were observed in non pregnant adults, with 86% of the patients being immunosuppressed. Nosocomial listeriosis, diagnosed in 23 patients (42%), was predominant in the group with immunosuppressive treatment (p = 0.0005). The main site of isolation was blood in 45 cases (82%), in the form of primary listeriosis (p < 0.0005). Global mortality was 49%, being greater in the group of patients with nosocomial infection (p = 0.01) and with primary bacteremia (p < 0.001). No patients without known risk factors or pertaining to the perinatal group have died. CONCLUSIONS: The use of an active system of registration of listeriosis facilitates better knowledge of its incidence, distribution and infection pattern thus allowing the early detection of epidemic outbreaks with the aim of controlling such an infection, given the social implications and morbidity of this disease.

Adolescent↗

Analysis of factors influencing the outcome and development of septic metastasis or relapse in Salmonella bacteremia.

One-hundred seventy-two consecutive adult patients with salmonella bacteremia documented by at least one positive blood culture were prospectively evaluated over a 10-year period. Salmonella enteritidis was isolated in 121 cases (70.3%), Salmonella typhimurium in 29 (16.9%), and other Salmonella species in 22 (12.8%). Twenty-seven patients (15.7%) developed septic metastasis; 21 patients (12.2%) died of bacteremia, and 24 (16.7%) of the 144 patients who survived had at least one relapse. A logistic regression analysis selected three variables as independently influencing outcome: septic shock (P = .005), coma (P = .029), and immunosuppression (P = .04). By means of the same statistical analysis, leukopenia (a white blood cell count of < 4 x 10(9)/L) was identified as an independent risk factor for relapse (P < .0001). The possibility of salmonella bacteremia must be considered when immunosuppressed patients have fever and no obvious source of infection. Treatment with a drug active against Salmonella species is essential in this population. Patients with leukopenia should be considered as recipients of prophylaxis for relapse.

Adolescent↗

Lipoprotein (a) and other risk factors in patients with non-insulin-dependent diabetes mellitus.

BACKGROUND: Studies have established a relationship between lipoprotein (a) [Lp(a)] levels and cardiovascular disease, but few have studied Lp(a) in patients with non-insulin-dependent diabetes mellitus (NIDDM). METHODS: We determined Lp(a) concentrations, levels of glycated hemoglobin, and the personal and family history of atherosclerosis in 88 patients with NIDDM (53 men and 35 women; age, 33-70 years) and 90 age- and sex-matched controls. Twenty-three patients with NIDDM had cardiovascular disease (CVD group) and 65 did not (non-CVD group). RESULTS: Lp(a) levels were higher in CVD than non-CVD patients (P < 0.01). Triglyceride levels negatively correlated with Lp(a) (r = -0.51, P < 0.05), independently of the metabolic control of diabetes. Patients with poor metabolic control (glycated hemoglobin > 7.5%) had higher Lp(a) levels than the control group (P < 0.05). Lp(a) levels were higher than 0.30 milligram in 11% of patients without CVD and 55% of those with CVD (P < 0.05). Cluster analysis showed that Lp(a), as well as total cholesterol, triglycerides, apolipoprotein B100, and age were independently related to CVD in patients with NIDDM (P < 0.001 for triglycerides and P < 0.05 for the other variables). CONCLUSIONS: Lp(a) levels can be considered an independent risk factor for the development of atherosclerosis in NIDDM.

Adult↗