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Francesc Gudiol

Publications and source records attributed to Francesc Gudiol.

At least 19 recordsLinked to original sources

Evaluation of fosfomycin alone and in combination with ceftriaxone or vancomycin in an experimental model of meningitis caused by two strains of cephalosporin-resistant Streptococcus pneumoniae.

OBJECTIVES: To study the in vitro and in vivo efficacy of fosfomycin, alone and in combination with ceftriaxone or vancomycin, against two strains of Streptococcus pneumoniae: HUB 2349 (fosfomycin and ceftriaxone, MICs 16 and 2 mg/L) and ATCC 51916 (MICs 4 and 32 mg/L). METHODS: Pharmacokinetics/pharmacodynamics data were collected from the study of eight infected animals after a single intravenous dose of 300 mg/kg of fosfomycin. Time-kill curves were plotted using CSF antibiotic concentrations achievable clinically. In the rabbit model, we studied the efficacy and effects on inflammation of treatment with fosfomycin 1200 mg/kg/day, ceftriaxone 100 mg/kg/day and vancomycin 30 mg/kg/day, over 26 h. RESULTS: Fosfomycin peak level in serum was 324.48 +/- 102.1 mg/L at 0.5 h; CSF penetration was 49.2%. Time-kill curves showed that fosfomycin was bactericidal against the ATCC 51916 strain and that the addition of fosfomycin to ceftriaxone or vancomycin was synergic against the HUB 2349 strain. Resistance to fosfomycin was detected both when fosfomycin was studied alone and in combination. In the rabbit model, fosfomycin showed bactericidal activity only against the ATCC 51916 strain. Combinations of fosfomycin with ceftriaxone or vancomycin were bactericidal against both strains; they improved efficacy and decreased CSF inflammatory parameters over monotherapies, without showing statistical differences in comparison with the combination of ceftriaxone and vancomycin. CONCLUSIONS: Fosfomycin in combination with ceftriaxone or vancomycin appeared to be effective for the treatment of experimental cephalosporin-resistant pneumococcal meningitis. These combinations are possible alternatives in cases of allergy or intolerance to first-line drugs or in rare meningitis caused by highly cephalosporin-resistant pneumococci.

Animals↗

Rifampicin/imipenem combination in the treatment of carbapenem-resistant Acinetobacter baumannii infections.

BACKGROUND: In the setting of a large endemic of Acinetobacter baumannii infections, treatment of those due to carbapenem-resistant strains, susceptible only to colistin, has become a major problem in our hospital during the past years. Successful results have been reported using colistin, but clinical experience with this antibiotic is limited. In our experimental studies using these strains in a mouse pneumonia model, the best results were observed with a combination of rifampicin and imipenem. METHODS: From July 2000 to September 2001, we performed a pilot study with patients suffering from serious infections due to carbapenem-resistant A. baumannii. Patients were treated with a rifampicin/imipenem combination and followed up prospectively. Cultures were repeated during and after treatment, and in vitro activity of rifampicin was monitored. Genotyping of these strains was performed by means of PFGE. RESULTS: Ten patients were selected: four with ventilator-associated pneumonia, and six with other infections (one catheter-related bacteraemia, five surgical infections). Three patients died, two of whom were considered therapeutic failures. In five of the seven patients who were cured, other procedures were also performed such as surgical drainage or catheter removal. In vitro development of high resistance to rifampicin was shown in seven (70%). PFGE demonstrated that initial isolates and high-resistant strains belonged to the same clones. CONCLUSIONS: The results of our study argue against the use of a rifampicin/imipenem combination for the treatment of carbapenem-resistant A. baumannii infections. However, combinations of rifampicin with other antibiotics merit further studies.

Acinetobacter Infections↗

Evaluation of ceftriaxone, vancomycin and rifampicin alone and combined in an experimental model of meningitis caused by highly cephalosporin-resistant Streptococcus pneumoniae ATCC 51916.

OBJECTIVES: The aim of the study was to assess the in vitro and in vivo efficacy of ceftriaxone, vancomycin and rifampicin alone and combined against Streptococcus pneumoniae ATCC 51916 (MIC of ceftriaxone: 32 mg/L). METHODS: In vitro killing curves were performed with clinically achievable CSF antibiotic concentrations. In the rabbit model of pneumococcal meningitis, we studied the efficacy of and effects on inflammation of treatment with ceftriaxone 100 mg/kg/day, vancomycin 30 mg/kg/day and rifampicin 15 mg/kg/day, alone and combined, over a 26 h period. RESULTS: Time-kill curves showed that vancomycin was bactericidal, and ceftriaxone and rifampicin produced a bacteriostatic effect. An additive effect was observed when combinations of ceftriaxone plus vancomycin were studied at subinhibitory concentrations. Emergence of resistance to rifampicin was detected both when rifampicin was studied alone and when combined with ceftriaxone or vancomycin. In the rabbit meningitis model, ceftriaxone was bacteriostatic, whereas rifampicin and vancomycin were bactericidal at 24 h. Although not synergistic, the combinations of ceftriaxone plus vancomycin or rifampicin, and vancomycin plus rifampicin, improved the efficacy of any antibiotic tested alone--all combinations were bactericidal from 6 h--and significantly decreased inflammatory parameters in CSF compared with control and ceftriaxone groups. CONCLUSION: Ceftriaxone plus vancomycin, and vancomycin plus rifampicin appeared to be effective in the therapy of experimental pneumococcal meningitis caused by highly cephalosporin-resistant strains such as ATCC 51916. Our results provide an experimental basis for using these combinations as empirical therapy for pneumococcal meningitis, regardless of the degree of cephalosporin resistance of the causative strain.

Animals↗

Experimental study on the efficacy of combinations of glycopeptides and beta-lactams against Staphylococcus aureus with reduced susceptibility to glycopeptides.

OBJECTIVES: The combination of glycopeptides and beta-lactams has been proposed as an alternative therapy against infections due to Staphylococcus aureus with reduced susceptibility to glycopeptides, though its role is still controversial. Our aim was to evaluate the efficacy (decrease in bacterial concentration after 24 h therapy) of these combinations both in vitro and in vivo. METHODS: Four strains of S. aureus with different glycopeptide susceptibility (MICs of vancomycin from 1 to 8 mg/L) were used. In vitro experiments were performed by means of time-kill curves while we used the mouse peritonitis model for in vivo evaluation. RESULTS: Combinations of glycopeptides and beta-lactams showed synergy in in vitro time-kill curves against the four staphylococcal strains, the highest efficacy being detected against the glycopeptide-intermediate S. aureus (GISA) strain (MIC = 8 mg/L) (Deltalog 24 h = -3.19 cfu/mL for vancomycin at 1/2 x MIC and oxacillinat 1/64 x MIC versus -0.56 cfu/mL for vancomycin alone at 1/2 x MIC). On the other hand, no significant increase in efficacy was observed in vivo in the experimental model. The efficacy of the combinations decreased in correlation to the decreasing susceptibility of the strains to glycopeptides, showing only residual activity against the GISA strain (Deltalog 24 h = -1.42 cfu/mL for vancomycin and cloxacillin versus -1.22 cfu/mL for vancomycin). CONCLUSIONS: In the in vivo setting we were unable to demonstrate the synergism between glycopeptides and beta-lactams observed in vitro; nor did combinations show antagonism against any of the strains. Though the usefulness of these combinations cannot be totally ruled out in highly specific clinical conditions, it seems unlikely that they will provide a serious therapeutic alternative in most hGISA and GISA infections in the coming years.

Animals↗

Epidemiologic changes in bacteremic pneumococcal disease in patients with human immunodeficiency virus in the era of highly active antiretroviral therapy.

BACKGROUND: The use of highly active antiretroviral therapy (HAART) may change the incidence of, and the risk and prognostic factors for, invasive pneumococcal disease in patients with human immunodeficiency virus (HIV). METHODS: We prospectively studied 142 episodes of pneumococcal bacteremia in 122 HIV-infected adults. Eighty-five episodes occurred in the pre-HAART era (1986-1996) and 57 in the HAART era (1997-2002). A case-control study was conducted to identify risk factors for pneumococcal bacteremia in the HAART era. RESULTS: The incidence of pneumococcal bacteremia dropped from 24.1 episodes per 1000 patient-years in the pre-HAART era to 8.2 episodes per 1000 patient-years in the HAART era (P = .01). Compared with patients in the pre-HAART era, patients in the HAART era had more associated comorbidity (42% vs 26%; P = .04), fewer recurrences of bacteremia (4% vs 15%; P = .04), and a higher 30-day mortality rate (26% vs 8%; P=.004). High antibiotic resistance rates were observed in both periods. By multivariate analysis, the major risk factors for pneumococcal bacteremia in the HAART era were associated comorbidity (adjusted odds ratio [OR], 3.36), alcohol abuse (adjusted OR, 5.28), prior hospitalization (adjusted OR, 3.38), current smoking (adjusted OR, 5.19), and CD4 cell count lower than 100 cells/muL (adjusted OR, 2.38); while use of HAART (adjusted OR, 0.37) and pneumococcal vaccine (adjusted OR, 0.39) were protective factors. CONCLUSIONS: The widespread use of HAART and pneumococcal vaccine may decrease the incidence of invasive pneumococcal disease in HIV-infected patients. Risk factors and prognosis of pneumococcal bacteremia in the HAART era are more similar to those reported in non-HIV-infected individuals.

Adult↗

Clinical outcomes for hospitalized patients with Legionella pneumonia in the antigenuria era: the influence of levofloxacin therapy.

BACKGROUND: Although the reduction in case-fatality rate recently observed among patients with Legionella pneumonia has been largely attributed to the progressive utilization of urine antigen testing, other factors, such as changes in empirical antibiotic therapy, may also have contributed. We have analyzed more-recent outcomes of Legionella pneumonia in an institution where urine antigen testing was reflexly performed in cases of community-acquired pneumonia without an etiological diagnosis. METHODS: From a prospective series of 1934 consecutive cases of community-acquired pneumonia in nonimmunocompromised adults, 139 cases of Legionella pneumophila pneumonia were selected for observational review. Legionella cases were analyzed for outcome with respect to antibiotic treatment, mortality, complications, length of stay, time to defervescence, and stability. RESULTS: The early case-fatality rate was 2.9% (4 of 139 patients), and the overall case-fatality rate was 5% (7 of 139 patients). One hundred twenty patients (86.3%) received an appropriate initial therapy, which included macrolides (i.e., erythromycin or clarithromycin) in 80 patients and levofloxacin in 40. Levofloxacin progressively replaced macrolides as the initial therapy during the study period. Compared with patients who received macrolides, patients who received levofloxacin had a faster time to defervescence (2.0 vs. 4.5 days; P<.001) and to clinical stability (3 vs. 5 days; P=.002). No differences were found regarding the development of complications (25% vs. 25%; P=.906) and case-fatality rate (2.5% vs. 5%; P=.518). The median length of hospital stay was 8 days in patients treated with levofloxacin and 10 days in those who received macrolides (P=.014). CONCLUSIONS: Legionella pneumonia is still associated with significant complications in hospitalized patients, but recent mortality is substantially lower than that found in earlier series. Levofloxacin may produce a faster clinical response than older macrolides, allowing for shorter hospital stay.

Adult↗

Outpatient care compared with hospitalization for community-acquired pneumonia: a randomized trial in low-risk patients.

BACKGROUND: The Pneumonia Severity Index (PSI) has been advocated as an objective measure of risk stratification to help determine the initial site of treatment for patients with community-acquired pneumonia. OBJECTIVE: To determine whether outpatient care of PSI-defined low-risk patients with community-acquired pneumonia is as safe and effective as hospitalization. DESIGN: Unblinded, randomized, controlled trial. SETTING: 2 tertiary care hospitals. PATIENTS: 224 immunocompetent adults in risk class II or III (PSI scores <or=90 points) who received a diagnosis of community-acquired pneumonia in the emergency department and had no extenuating circumstances. INTERVENTION: Outpatient care with oral levofloxacin therapy or hospitalization with sequential intravenous and oral levofloxacin therapy. MEASUREMENTS: The primary end point was the percentage of patients with an overall successful outcome at the end of treatment, according to 7 predefined criteria. Secondary end points included patients' quality of life and satisfaction. RESULTS: Overall successful outcome was achieved in 83.6% of outpatients and 80.7% of hospitalized patients (absolute difference, 2.9 percentage points [95% CI, -7.1 to 12.9 percentage points]). More outpatients were satisfied with their overall care (91.2% vs. 79.1%; absolute difference, 12.1 percentage points [CI, 1.8 to 22.5 percentage points]). Quality of life and the percentages of patients with adverse drug reactions (9.1% vs. 9.6%), medical complications (0.9% vs. 2.6%), subsequent hospital admissions (6.3% vs. 7.0%), and overall mortality (0.9% vs. 0%) were similar in the outpatient and hospitalization groups. LIMITATIONS: The power to detect a serious complication, such as death, was limited given the relatively small sample size. CONCLUSIONS: In selected patients who had community-acquired pneumonia, PSI risk class II and III, and were treated with levofloxacin, outpatient care in the absence of respiratory failure, unstable comorbid conditions, complicated pleural effusions, and social problems was as safe and effective as hospitalization and provided greater patient satisfaction.

Administration, Oral↗

Antibiotic combinations for serious infections caused by carbapenem-resistant Acinetobacter baumannii in a mouse pneumonia model.

OBJECTIVES: Successful therapy of carbapenem-resistant Acinetobacter baumannii strains has been reported with colistin, but recently we argued against its use as monotherapy because of the poor results obtained in a mouse pneumonia model. Our aim was to identify antibiotic combinations that were valid therapeutic alternatives in the same model. METHODS: We used two carbapenem-resistant A. baumannii strains (D and E; MICs of imipenem, 8 and 512 mg/L, respectively). MICs of tobramycin, rifampicin and colistin for both strains were 8, 8 and 0.5 mg/L, respectively. RESULTS: In infections caused by strain D, lung bacterial counts (log(10) cfu/g, mean +/- s.d.) were: controls (10.86+/-0.25), imipenem (5.99+/-0.59, P < 0.05 versus controls), and colistin (10.43 +/- 1.09); imipenem + tobramycin was the most active combination (5.46+/-0.62, P < 0.05 versus controls). In infections caused by strain E, results were: controls (10.82+/-0.33), rifampicin (5.62+/-0.26, P < 0.05 versus controls), colistin (8.38+/-1.22, P < 0.05 versus controls), and imipenem (11.01+/-0.2); rifampicin + imipenem (3.79+/-0.99) and rifampicin + tobramycin (3.96+/-0.30) were the most active combinations (P < 0.05); results with rifampicin + colistin (5.59+/-1.17) were similar to those with rifampicin alone. CONCLUSIONS: Our data indicate that imipenem can still be the best alternative for carbapenem-resistant A. baumannii infections with moderate levels of imipenem resistance, preferably combined with aminoglycosides. For strains highly resistant to imipenem, a combination of rifampicin with imipenem, tobramycin or colistin may be useful, if resistance to rifampicin is only moderate.

Acinetobacter Infections↗

Causes and factors associated with early failure in hospitalized patients with community-acquired pneumonia.

BACKGROUND: Early failure is a matter of great concern in the treatment of community-acquired pneumonia. However, information on its causes and risk factors is lacking. METHODS: Observational analysis of a prospective series of 1383 nonimmunosuppressed hospitalized adults with community-acquired pneumonia. Early failure was defined as lack of response or worsening of clinical or radiologic status at 48 to 72 hours requiring changes in antibiotic therapy or invasive procedures. Concordance of antimicrobial therapy was examined for cases with an etiologic diagnosis. RESULTS: At 48 to 72 hours, 238 patients (18%) remained febrile, but most of them responded without further changes in antibiotic therapy. Eighty-one patients (6%) had early failure. The main causes of early failure were progressive pneumonia (n = 54), pleural empyema (n = 18), lack of response (n = 13), and uncontrolled sepsis (n = 9). Independent factors associated with early failure were older age (>65 years) (odds ratio [OR], 0.35), multilobar pneumonia (OR, 1.81), Pneumonia Severity Index score greater than 90 (OR, 2.75), Legionella pneumonia (OR, 2.71), gram-negative pneumonia (OR, 4.34), and discordant antimicrobial therapy (OR, 2.51). Compared with treatment responders, early failures had significantly higher rates of complications (58% vs 24%) and overall mortality (27% vs 4%) (P<.001 for both). CONCLUSIONS: Early failure is infrequent but is associated with high morbidity and mortality rates. Its detection and management require careful clinical assessment. Most cases occur because of inadequate host-pathogen responses. Discordant therapy is a less frequent cause of failure, which may be preventable by rational application of the current antibiotic guidelines.

Aged↗

A mouse peritonitis model for the study of glycopeptide efficacy in GISA infections.

In recent years, the emergence of Staphylococcus aureus strains with reduced susceptibility to glycopeptides has raised considerable concern. We studied the efficacy of vancomycin and teicoplanin, as well as cloxacillin and cefotaxime, against the infection caused by four S. aureus strains with different glycopeptide and beta-lactam susceptibilities (strains A, B, C, and D; MICs for vancomycin of 1, 2, 4, and 8 microg/ml respectively), using a modified model of mouse peritonitis. This optimized model appeared to be straightforward and reproducible, and was able to detect low differences in bacterial killing between antibiotics and also between different S. aureus strains. Bactericidal activities in peritoneal fluid for vancomycin, teicoplanin, cloxacillin, and cefotaxime decreased from -2.98, -2.36, -3.22, and -3.57 log(10) cfu/ml, respectively, in infection by strain A (MICs for vancomycin and cloxacillin of 1 and 0.38 microg/ml, respectively) to -1.22, -0.65, -1.04, and +0.24 in peritonitis due to strain D (MICs for vancomycin and cloxacillin of 8 and 1,024 microg/ml). Our data confirm the superiority of beta-lactams against methicillin-susceptible S. aureus and show that bactericidal activity of glycopeptides decreases significantly with slight increases in MICs; this finding suggests a reduced efficacy of glycopeptides in the treatment of serious glycopeptide-intermediate S. aureus infections.

Animals↗

Contribution of a urinary antigen assay (Binax NOW) to the early diagnosis of pneumococcal pneumonia.

We evaluated the usefulness of a rapid urinary antigen test (Binax NOW; Binax) to detect Streptococcus pneumoniae for the early diagnosis of community-acquired pneumococcal pneumonia (PP) in 220 nonseverely immunosuppressed adults. We compared results of this test with those of sputum Gram staining. The rapid urinary antigen test showed limited sensitivity (65.9%; 95% confidence interval [CI], 51.4-80.4) but high specificity (100%; 95% CI, 99.7-100) for diagnosing PP. The test was more sensitive for patients with versus those without high-risk pneumonia (94% vs. 63%; P<.001) and for patients without versus those with demonstrative results of a sputum Gram stain (97% vs. 55%; P<.001), and it tended to be more sensitive for patients with versus those without bacteremic PP (92% vs. 74%; P=NS). Rapid urinary antigen testing permitted early diagnosis of PP in 26% more patients than did Gram staining but missed 22% of the rapid diagnoses initially identified by Gram staining. On the basis of our results, a sequential approach is proposed, with reservation of urinary antigen testing for high-risk patients for whom demonstrative results of a sputum Gram stain are unavailable.

Adult↗

Clinical diagnosis of Legionella pneumonia revisited: evaluation of the Community-Based Pneumonia Incidence Study Group scoring system.

This prospective case-control study sought to identify differences in presentation between Legionella pneumonia (LP) diagnosed by urinary antigen and bacteremic pneumococcal pneumonia (PP), with the aim of assessing the ability of physicians to recognize such differences at admission and validating the Community-Based Pneumonia Incidence Study (CBPIS) Group scoring system for LP diagnosis. Significant differences in presentation were found: male sex, previous receipt of beta-lactam therapy, and temperature >39 degrees C were positively associated with LP; purulent sputum, pleuritic chest pain, and previous upper respiratory tract infection were negatively associated with LP. Physicians considered Legionella to be the most likely diagnosis in 52 (64%) of 81 LP cases and in 8 (6%) of 136 PP cases. Initial administration of a macrolide and rifampin and requests for urinary antigen testing for Legionella at admission were significantly more frequent among patients with LP. Overall, the CBPIS score did not differentiate reliably between LP and PP. Although certain presenting clinical features may allow recognition of LP, it is difficult to express them in a reliable scoring system.

Aged↗

[beta-Lactam antibiotics].

Betalactams, which act by inhibiting the last phase of bacterial cell wall synthesis, constitute the largest family of antimicrobial agents and the most extensively used in current clinical practice. These drug have a slow bactericidal action that is relatively independent of plasma concentrations, little toxicity and a broad therapeutic margin. Their spectrum has increased over the years with the incorporation of new molecules having greater activity against gram-negative bacilli. Nevertheless, the progressive emergence of acquired resistance has limited the empirical use of betalactams and their efficacy in certain situations. Despite this problem, penicillin is still the treatment of choice for a large number of classic infections, cephalosporins are widely used in surgical prophylaxis and severe community-acquired infections, carbapenems are the choice for mixed nosocomial and multiresistant bacterial infections and betalactamase inhibitors permit the effective use of amino- and ureido-penicillins in highly significant infections.

Anti-Bacterial Agents↗

Community-acquired pneumonia in very elderly patients: causative organisms, clinical characteristics, and outcomes.

We performed an observational analysis of prospectively collected data on 1,474 adult patients who were hospitalized for community-acquired pneumonia; 1,169 patients were under 80 years of age and 305 (21%) patients were over 80 years ("very elderly"). Mean patient ages were 60 years in the former group and 85 years in the latter group. Severely immunosuppressed patients and nursing-home residents were not included. Comorbidities significantly associated with older age were chronic obstructive pulmonary disease, chronic heart disease, and dementia. The most common causative organism was Streptococcus pneumoniae (23% in both groups). Aspiration pneumonia was more frequent in the very elderly (5% in younger patients versus 10% in the very elderly); Legionella pneumophila (8% in younger patients versus 1% in the very elderly) and atypical agents (7% in younger patients versus 1% in the very elderly) were rarely recorded in the very elderly. While very elderly patients complained less frequently of pleuritic chest pain, headache, and myalgias, they were more likely to have absence of fever and altered mental status on admission. No significant differences were observed between groups as regards incidence of classic bacterial pneumonia syndrome (60% versus 59%) in 343 patients with pneumococcal pneumonia. The development of inhospital complications (26% in younger versus 32% in very elderly patients) as well as early mortality (2% in younger versus 7% in very elderly patients) and overall mortality (6% in younger versus 15% very elderly patients) were significantly higher in very elderly patients. Acute respiratory failure and shock/multiorgan failure were the most frequent causes of death, especially of early mortality. Factors independently associated with 30-day mortality in the very elderly were altered mental status on admission (odds ratio, 3.69), shock (odds ratio, 10.69), respiratory failure (odds ratio, 3.50), renal insufficiency (odds ratio, 5.83), and Gram-negative pneumonia (odds ratio, 20.27).

Adolescent↗

Experimental study of LY333328 (oritavancin), alone and in combination, in therapy of cephalosporin-resistant pneumococcal meningitis.

Using a rabbit model of meningitis, we sought to determine the efficacy of LY333328, a semisynthetic glycopeptide, in the treatment of cephalosporin-resistant pneumococcal meningitis. LY333328 was administered at a dose of 10 mg/kg of body weight/day, alone and in combination with ceftriaxone at 100 mg/kg/day with or without dexamethasone at 0.25 mg/kg/day. The therapeutic groups were treated with LY333328 with or without dexamethasone and LY333328-ceftriaxone with or without dexamethasone. Rabbits were inoculated with a cephalosporin-resistant pneumococcal strain (ceftriaxone MIC, 2 microg/ml; penicillin MIC, 4 microg/ml; LY333328 MIC, 0.008 microg/ml) and were treated over a 26-h period beginning 18 h after inoculation. The bacterial counts in cerebrospinal fluid (CSF), the white blood cell count, the lactic acid concentration, the CSF LY333328 concentration, and bactericidal and bacteriostatic activities were determined at different time points. In vitro, LY333328 was highly bactericidal and its use in combination with ceftriaxone at one-half the MIC was synergistic. In the rabbit model, LY333328 alone was an excellent treatment for cephalosporin-resistant pneumococcal meningitis, with a rapid decrease in colony counts and no therapeutic failures. The use of LY333328 in combination with ceftriaxone improved the activity of LY333328, but no synergistic effect was observed. The combination of LY333328 with dexamethasone was also rapidly bactericidal, but two therapeutic failures were observed. The combination of LY333328 with ceftriaxone and dexamethasone was effective, without therapeutic failures.

Animals↗

Molecular inflammatory responses measured in blood of patients with severe community-acquired pneumonia.

In order to analyze the characteristics of the inflammatory response occurring in blood during pneumonia, we studied 38 patients with severe community-acquired pneumonia. Venous and arterial blood samples were collected at study entry and on days 1, 2, 3, 5, and 7 after inclusion. The concentrations of proinflammatory (tumor necrosis factor alpha [TNF-alpha], interleukin 1beta [IL-1beta], IL-6, and IL-8) and anti-inflammatory (IL-10) cytokines were determined in order to detect differences related to the origin of the sample, the causative organism, the clinical variables, and the final outcome of the episode. Legionella pneumonia infections showed higher concentrations of TNF-alpha, IL-6, IL-8, and IL-10. After 24 h, plasma IL-6, IL-8, and IL-10 concentrations in pneumococcal episodes increased, whereas in the same time interval, cytokine concentrations in Legionella episodes markedly decreased. The characteristics of the inflammatory response in bacteremic pneumococcal episodes were different from those in nonbacteremic episodes, as indicated by the higher plasma cytokine concentrations in the former group. Finally, our analysis of cytokine concentrations with regard to the outcome--in terms of the need for intensive care unit admittance and/or mechanical ventilation as well as mortality--suggests that there is a direct relationship between the intensity of the inflammatory response measured in blood and the severity of the episode.

Community-Acquired Infections↗

The effect of cephalosporin resistance on mortality in adult patients with nonmeningeal systemic pneumococcal infections.

PURPOSE: To evaluate the clinical relevance of cephalosporin (ceftriaxone/cefotaxime) resistance among patients with nonmeningeal systemic pneumococcal infection. SUBJECTS AND METHODS: From January 1994 to October 2000, we prospectively studied 522 episodes of nonmeningeal systemic pneumococcal infections (448 pneumonias) in 499 adults who were treated according to hospital guidelines. In vitro antibiotic susceptibility, as the minimum inhibitory concentration (MIC), was determined by microdilution method. The MIC methods and breakpoints (cutoffs) were established by the National Committee for Clinical Laboratory Standards. RESULTS: Of the 522 pneumococcal strains, 413 strains (79%) were susceptible to ceftriaxone/cefotaxime, MIC < or =0.5 microg/mL; 79 (15%) were intermediate, MIC = 1 microg/mL; and 30 (6%) were resistant, MIC = 2 microg/mL. After adjusting for several variables, including pneumococcal serogroups/serotypes, infections due to nonsusceptible (intermediate and resistant) pneumococcal strains were independently associated with prior antibiotic therapy, with an odds ratio of 5.9 (95% confidence interval: 2.6 to 13.6). Thirty-day mortality among the 185 patients who were treated with ceftriaxone (1 g/d) or cefotaxime (1.5 g every 8 hours) did not differ by cephalosporin susceptibility: 18% (26/148) among those with susceptible organisms, 13% (3/24) with intermediate organisms, and 15% (2/13) in resistant cases (P = 0.81). CONCLUSION: Ceftriaxone or cefotaxime were effective in treating patients with nonmeningeal systemic pneumococcal infections caused by strains with MIC < or =2 microg/mL. These results support the newly established ceftriaxone/cefotaxime MIC breakpoints (cutoffs) for nonmeningeal pneumococcal infections.

Adult↗