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J Mensa

Publications and source records attributed to J Mensa.

At least 37 records · Page 2Linked 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↗

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Journal Article↗

Antimicrobial treatment failures in patients with community-acquired pneumonia: causes and prognostic implications.

The aim of the study was to determine the causes and prognostic implications of antimicrobial treatment failures in patients with nonresponding and progressive life-threatening, community-acquired pneumonia. Forty-nine patients hospitalized with a presumptive diagnosis of community-acquired pneumonia during a 16-mo period, failure to respond to antimicrobial treatment, and documented repeated microbial investigation >/= 72 h after initiation of in-hospital antimicrobial treatment were recorded. A definite etiology of treatment failure could be established in 32 of 49 (65%) patients, and nine additional patients (18%) had a probable etiology. Treatment failures were mainly infectious in origin and included primary, persistent, and nosocomial infections (n = 10 [19%], 13 [24%], and 11 [20%] of causes, respectively). Definite but not probable persistent infections were mostly due to microbial resistance to the administered initial empiric antimicrobial treatment. Nosocomial infections were particularly frequent in patients with progressive pneumonia. Definite persistent infections and nosocomial infections had the highest associated mortality rates (75 and 88%, respectively). Nosocomial pneumonia was the only cause of treatment failure independently associated with death in multivariate analysis (RR, 16.7; 95% CI, 1.4 to 194.9; p = 0.03). We conclude that the detection of microbial resistance and the diagnosis of nosocomial pneumonia are the two major challenges in hospitalized patients with community-acquired pneumonia who do not respond to initial antimicrobial treatment. In order to establish these potentially life-threatening etiologies, a regular microbial reinvestigation seems mandatory for all patients presenting with antimicrobial treatment failures.

Community-Acquired Infections↗

[Tolerability and safety of levofloxacinin long-term treatment].

Levofloxacin is a useful quinolone for patients infected with osteomyelitis or tuberculosis. There is little information on the tolerance and safety of levofloxacin in long-term treatment. Fifteen patients (10 men and 5 women) with prosthetic joint infection or chronic osteomyelitis were analyzed. The treatment was levofloxacin (500 mg/d) and rifampicin (600 mg/d). Controls were performed monthly during the treatment, and after that every six months. Problems that were likely related to medication were noted by medical interview. Analyses of hepatic and renal function were performed at each visit. The mean age was 64 years. Ten patients had prosthetic joint infection, two chronic osteomyelitis, two osteosynthetic device infection and one silicone graft infection. Staphylococcus aureus was isolated in eight cases, staphylococcus coagulase being negative in five, and the cultures negative in two cases. The mean duration of treatment was 3.6 months (range 2-6 months). No adverse reactions were observed in seven patients (46%). Occasional digestive symptoms were reported in six patients (40%), and two cases (13%) presented light diarrhea. These patients also took antiinflammatory treatment. Sleeplessness was observed in one patient (6%). Tendinitis or alterations in hepatic function were not observed. In no case was the treatment changed due to adverse reactions. It was concluded that levofloxacin is well tolerated and safe and could be an option for infections that require long-term treatment.

Aged↗

[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↗

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↗

Pneumonia acquired in the community through drug-resistant Streptococcus pneumoniae.

The aim of the study was to determine the incidence of and risk factors for drug resistance of Streptococcus pneumoniae, and its impact on the outcome among hospitalized patients of pneumococcal pneumonia acquired in the community. Consecutive patients with culture-proven pneumococcal pneumonia were prospectively studied with regard to the incidence of pneumococcal drug resistance, potential risk factors, and in-hospital outcome variables. A total of 101 patients were studied. Drug resistance to penicillin, cephalosporin, or a macrolide drug was found in pneumococci from 52 of the 101 (52%) patients; 49% of these isolates were resistant to penicillin (16% intermediate resistance, 33% high resistance), 31% to cephalosporin (22% intermediate and 9% high resistance), and 27% to a macrolide drug. In immunocompetent patients, age > 65 yr was significantly associated with resistance to cephalosporin (odds ratio [OR]: 5.0; 95% confidence interval [CI]: 1.3 to 18.8, p = 0. 01), and with the presence of > 2 comorbidities with resistance to penicillin (OR: 4.7; 95% CI: 1.2 to 19.1; p < 0.05). In immunosuppressed patients, bacteremia was inversely associated with resistance to penicillin and cephalosporin (OR: 0.04; 95% CI: 0.003 to 0.45; p < 0.005; and OR: 0.46; 95% CI: 0.23 to 0.93; p < 0.05, respectively). Length of hospital stay, severity of pneumonia, and complications were not significantly affected by drug resistance. Mortality was 15% in patients with any drug resistance, as compared with 6% in those without resistance. However, any drug resistance was not significantly associated with death (relative risk [RR]: 2. 5; 95% CI: 0.7 to 8.9; p = 0.14). Moreover, attributable mortality in the presence of discordant antimicrobial treatment was 12%, as compared with 10% (RR: 1.2; 95% CI: 0.3 to 5.3; p = 0.67) in the absence of such treatment. We conclude that the incidence of drug-resistant pneumococci was high. Risk factors for drug resistance included advanced age, comorbidity, and (inversely) bacteremia. Outcome was not significantly affected by drug resistance.

Adult↗

Etiology of community-acquired pneumonia: impact of age, comorbidity, and severity.

The aim of this study was to determine the etiology of community-acquired pneumonia (CAP) and the impact of age, comorbidity, and severity on microbial etiologies of such pneumonia. Overall, 395 consecutive patients with CAP were studied prospectively during a 15-mo period. Regular microbial investigation included examination of sputum, blood culture, and serology. Sampling of pleural fluid, transthoracic puncture, tracheobronchial aspiration, and protected specimen brush (PSB) sampling were performed in selected patients. The microbial etiology was determined in 182 of 395 (46%) cases, and 227 pathogens were detected. The five most frequent pathogens were Streptococcus pneumoniae (65 patients [29%]), Haemophilus influenzae (25 patients [11%]), Influenza virus A and B (23 patients [10%]), Legionella sp. (17 patients [8%]), and Chlamydia pneumoniae (15 patients [7%]). Gram-negative enteric bacilli (GNEB) accounted for 13 cases (6%) and Pseudomonas aeruginosa for 12 cases of pneumonia (5%). Patients aged < 60 yr were at risk for an "atypical" bacterial etiology (odds ratio [OR]: 2.3; 95% confidence interval [CI]: 1.2 to 4.5), especially Mycoplasma pneumoniae (OR: 5.3; 95% CI: 1.7 to 16.8). Comorbid pulmonary, hepatic, and central nervous illnesses, as well as current cigarette smoking and alcohol abuse, were all associated with distinct etiologic patterns. Pneumonia requiring admission to the intensive care unit was independently associated with the pathogens S. pneumoniae (OR: 2.5; 95% CI: 1.3 to 4.7), gram-negative enteric bacilli, and P. aeruginosa (OR: 2.5; 95% CI: 0.99 to 6.5). Clinical and radiographic features of "typical" pneumonia were neither sensitive nor specific for the differentiation of pneumococcal and nonpneumococcal etiologies. These results support a management approach based on the associations between etiology and age, comorbidity, and severity, instead of the traditional syndromic approach to CAP.

Adult↗

Severe community-acquired pneumonia. Risk factors and follow-up epidemiology.

The aim of the study was to determine risk factors for severe community-acquired pneumonia (CAP) as well as to compare microbial patterns of severe CAP to a previous study from our respiratory intensive care unit (ICU) originating from 1984 to 1987. Patients admitted to the ICU according to clinical judgment were defined as having severe CAP. For the study of risk factors, a hospital-based case-control design was used, matching each patient with severe CAP to a patient hospitalized with CAP but not requiring ICU admission. Microbial investigation included noninvasive and invasive techniques. Overall, 89 patients with severe CAP were successfully matched to a control patient. The presence of an alcohol ingestion of >/= 80 g/d (odds ratio [OR] 3.9, 95% confidence interval [CI] 1.4 to 10.6, p = 0.008) was found to be an independent risk factor for severe CAP and prior ambulatory antimicrobial treatment (OR 0.37, 95% CI 0.17 to 0.79, p = 0.009) to be protective. Streptococcus pneumoniae (24%) continued to be the most frequent pathogen; however, 48% of strains were drug-resistant. "Atypical" bacterial pathogens were significantly more common (17% versus 6%, p = 0.006) and Legionella spp. less common (2% versus 14%, p = 0.004) than in our previous study, whereas gram-negative enteric bacilli (GNEB) and Pseudomonas aeruginosa continued to represent important pathogens (6% and 5%, respectively). Our findings provide additional evidence for the importance of the initiation of early empiric antimicrobial treatment for a favorable outcome of CAP. Variations of microbial patterns are only in part due to different epidemiological settings. Therefore, initial empiric antimicrobial treatment will also have to take into account local trends of changing microbial patterns.

Adolescent↗

[In vitro activity of fluoroquinolones and oral beta lactam antibiotics against clinical isolates of Escherichia coli].

We studied the in vitro activity of amoxicillin-clavulanic acid, cefprozil, cefuroxime, cefpodoxime, ceftibuten, cefixime, ciprofloxacin and sparfloxacin against 400 strains of Escherichia coli. The strains were obtained from urine cultures from patients with community acquired urinary tract infection who were treated in our hospital in 1997 and 1998. Among the six betalactams, ceftibuten and cefixime were the most active in vitro with MIC90 of 0.5 mg/l. Both antimicrobials were 2- and 16-fold more active than cefpodoxime (MIC90 1 mg/l) and cefprozil (MIC90 8 mg/l), respectively. However, overall, the four cephalosporins inhibited between 95% and 99% of isolates. Cefuroxime and amoxicillin-clavulanic acid showed less activity with a MIC90 of 16 mg/l. The percentage of fluoroquinolone-resistant strains was 24% with a similar activity to ciprofloxacin (MIC90 32 mg/l) and sparfloxacin (MIC90 64 mg/l).

Administration, Oral↗

[Pneumonia caused by Haemophilus influenzae. Study in a series of 58 patients].

Haemophilus influenzae tends to form part of the usual respiratory flora in adults, especially if they have a chronic underlying disease or are smokers. Pneumonia due to H. influenzae is frequently involved in respiratory infections and its level of resistance to ampicillin has remained stable over the last five years. Most of the literature on the subject was published more than 10 years ago. In this study, we describe the clinical features and evolution of 58 adult patients admitted to hospital for pneumonia due to H. influenzae over a 2-year period, with this group accounting for 6.5% of all the patients admitted with pneumonia during this time period. The etiological diagnosis was made using a good quality sputum sample. Forty patients (69%) were male. The mean age (+/- SD) of the group was 67 (+/-16.8) years and all the patients had at least one underlying disease. The mean duration of the symptoms was 6.7 days. All patients presented an increase in the quantity or purulence of the sputum. On admittance, respiratory failure was present in 52 patients (90%). Gram-negative coccus-bacilli were observed in the direct sputum test and H. influenzae grew in the culture. In two cases, H. influenzae was recovered from the blood culture and in one from bronchial aspiration obtained through bronchoscopy. Another pathogen was identified in 28 patients (48%). In 21 it was another pyogenic bacteria (15 S. pneumoniae, 4 M. catharralis, 1 K. pneumoniae, 1 E. coli), an atypical microorganism in 5 (3 C. pneumoniae, 2 C. burnetii) and a respiratory virus in 2 (syncytial and influenza A). Atypical bacteria and respiratory virus were detected using serological techniques. The radiographic infiltrate was unilobar in 54 of the 58 patients and all showed an alveolar pattern. The empirical treatment included the administration of a third generation cephalosporin (or a fluoroquinolone in patients allergic to penicillin). The evolution was favorable in all the cases in which H. influenzae was the only pathogen or was accompanied by an atypical microorganism or a respiratory virus. Four patients with mixed bacterial pneumonia died (2 S. pneumoniae, 1 E. coli and 1 M. catharralis). The study indicates that pneumoniae due to H. influenzae affects a population with an underlying disease, preferably pulmonary, that it has a longer clinical period than that for pneumococcal pneumonia, that it is slightly bacteremic and, that, usually, it evolves benignly with a low mortality.

Adult↗

[Pneumonia due to Haemophilus influenzae.Study in a series of 58 patients]

Haemophilus influenzae tends to form part of the usual respiratory flora in adults, especially if they have a chronic underlying disease or are smokers. Pneumonia due to H. influenzae is frequently involved in respiratory infections and its level of resistance to ampicillin has remained stable over the last five years. Most of the literature on the subject was published more than 10 years ago. In this study, we describe the clinical features and evolution of 58 adult patients admitted to hospital for pneumonia due to H. influenzae over a 2-year period, with this group accounting for 6.5% of all the patients admitted with pneumonia during this time period. The etiological diagnosis was made using a good quality sputum sample. Forty patients (69%) were male. The mean age (+/- SD) of the group was 67 (+/-16.8) years and all the patients had at least one underlying disease. The mean duration of the symptoms was 6.7 days. All patients presented an increase in the quantity or purulence of the sputum. On admittance, respiratory failure was present in 52 patients (90%). Gram-negative coccus-bacilli were observed in the direct sputum test and H. influenzae grew in the culture. In two cases, H. influenzae was recovered from the blood culture and in one from bronchial aspiration obtained through bronchoscopy. Another pathogen was identified in 28 patients (48%). In 21 it was another pyogenic bacteria (15 S. pneumoniae, 4 M. catharralis, 1 K. pneumoniae, 1 E. coli), an atypical microorganism in 5 (3 C. pneumoniae, 2 C. burnetii) and a respiratory virus in 2 (syncytial and influenza A). Atypical bacteria and respiratory virus were detected using serological techniques. The radiographic infiltrate was unilobar in 54 of the 58 patients and all showed an alveolar pattern. The empirical treatment included the administration of a third generation cephalosporin (or a fluoroquinolone in patients allergic to penicillin). The evolution was favorable in all the cases in which H. influenzae was the only pathogen or was accompanied by an atypical microorganism or a respiratory virus. Four patients with mixed bacterial pneumonia died (2 S. pneumoniae, 1 E. coli and 1 M. catharralis). The study indicates that pneumoniae due to H. influenzae affects a population with an underlying disease, preferably pulmonary, that it has a longer clinical period than that for pneumococcal pneumonia, that it is slightly bacteremic and, that, usually, it evolves benignly with a low mortality.

Journal Article↗