Prognosis and Outcomes of Patients With Community-Acquired Pneumonia

Outcomes in lower respiratory tract infections and the impact of antimicrobial drug resistance

Numerous published studies have documented the rapid rise in antimicrobial drug resistance among common respiratory pathogens, particularly Streptococcus pneumoniae. Yet, surprisingly few studies have evaluated the impact of these in vitro findings on clinical outcomes. Outcomes research is the measurement of the impact of illness and the effect of treatment on clinically relevant end-points. Studies of patients with community-acquired pneumonia have established certain expected rates of outcomes, including mortality, clinical complications, and time to resolution of symptoms. Recent studies have identified specific processes of care and treatment choices that have an impact upon these outcomes. However, there are no well-controlled studies that provide definitive estimates of the magnitude of the impact of antimicrobial therapy on these outcomes for patients with community-acquired pneumonia or other respiratory tract infections, such as acute exacerbations of chronic bronchitis. Most studies of the impact of drug resistance on outcomes for patients with respiratory tract infections have focused on the impact of beta-lactam drug resistance on outcomes for patients with community-acquired pneumococcal pneumonia. In general, these studies have demonstrated that outcomes are not affected by current levels of drug resistance, but most studies are hampered by small sample size, inability to control adequately for severity of illness and concordance of therapy, and inclusion of few subjects with high-level drug resistance. Additional studies are urgently needed to assess better whether the current empiric treatment guidelines are adequate or will need to be adjusted as patterns of resistance continue to evolve.

Efficacy of amoxicillin-sulbactam, given twice-a-day, for the treatment of community-acquired pneumonia: a clinical trial based on a pharmacodynamic model

The present multicenter study reports the results of a clinical trial, designed on the basis of a pharmacodynamic study published previously (Bantar et al., J. Chemother 2000; 12: 223-227) to assess the efficacy of amoxicillin/sulbactam (875 mg/125 mg), given orally twice-a-day for 7 days in the treatment of patients with community-acquired pneumonia (CAP). Eighty-four evaluable subjects older than 19 years with clinical symptoms and features suggestive of CAP, consulting from June 2000 to March 2002 and meeting the PORT risk class I through III, were enrolled in the study. Mean age (y +/- standard deviation) was 46.7 +/- 16.3 and 62% of the patients had some co-morbidity predisposing for CAP. Several individuals (77.4%) fell into a low-risk class (i.e. PORT I or II) and 22.6% of patients belonged to a moderate-risk class at the start of treatment. Six patients (6.45%) had pneumococcal bacteremia. Streptococcus pneumoniae was the organism most frequently isolated (61.9% of all the patients in whom an etiologic diagnosis was made), followed by Haemophilus influenzae. Clinical success was observed in 97.6% of the patients (confidence interval 95%, 94.3%-100%). Almost all the individuals with clinical success became afebrile within the first 3 days of therapy. Ten patients (11.8%) reported mild or moderate adverse events (especially diarrhea) possibly related to the antimicrobial therapy, but this did not lead to withdrawal from the trial. The results of this study suggest that amoxicillin/sulbactam (875 mg/125 mg) is an efficacious and well tolerated option for treating patients with CAP belonging to a low-moderate risk class and support the use of a short, oral (7-day) b.i.d. regimen.

Detection of Pneumocystis DNA in samples from patients suspected of bacterial pneumonia--a case-control study

BACKGROUND

Pneumocystis jiroveci (formerly known as P. carinii f.sp. hominis) is an opportunistic fungus that causes Pneumocystis pneumonia (PCP) in immunocompromised individuals. Pneumocystis jiroveci can be detected by polymerase chain reaction (PCR). To investigate the clinical importance of a positive Pneumocystis-PCR among HIV-uninfected patients suspected of bacterial pneumonia, a retrospective matched case-control study was conducted.

METHODS

Respiratory samples from 367 patients suspected of bacterial pneumonia were analysed by PCR amplification of Pneumocystis jiroveci. To compare clinical factors associated with carriage of P. jiroveci, a case-control study was done. For each PCR-positive case, four PCR-negative controls, randomly chosen from the PCR-negative patients, were matched on sex and date of birth.

RESULTS

Pneumocystis-DNA was detected in 16 (4.4%) of patients. The median age for PCR-positive patients was higher than PCR-negative patients (74 vs. 62 years, p = 0.011). PCR-positive cases had a higher rate of chronic or severe concomitant illness (15 (94%)) than controls (32 (50%)) (p = 0.004). Twelve (75%) of the 16 PCR positive patients had received corticosteroids, compared to 8 (13%) of the 64 PCR-negative controls (p < 0.001). Detection of Pneumocystis-DNA was associated with a worse prognosis: seven (44%) of patients with positive PCR died within one month compared to nine (14%) of the controls (p = 0.01). None of the nine PCR-positive patients who survived had developed PCP at one year of follow-up.

CONCLUSIONS

Our data suggest that carriage of Pneumocystis jiroveci is associated with old age, concurrent disease and steroid treatment. PCR detection of P. jiroveci has low specificity for diagnosing PCP among patients without established immunodeficiency. Whether overt infection is involved in the poorer prognosis or merely reflects sub-clinical carriage is not clear. Further studies of P. jiroveci in patients receiving systemic treatment with corticosteroids are warranted.

Cost-effectiveness of the pneumococcal vaccine in healthy younger adults

OBJECTIVES

Routine vaccination for Streptococcus pneumoniae has been recommended as a cost-effective measure for elderly and immunocompromised patients, yet no analysis has been performed for healthy younger adults in America. The authors evaluated the cost-effectiveness of the pneumococcal vaccine and determined the net health benefits conferred for the healthy young adult population.

METHODS

The authors developed a decision model to compare the health and economic outcomes of vaccinate versus do not vaccinate for S. pneumoniae.

RESULTS

Vaccinating patients for S. pneumoniae generates benefits that are dependent on incidence rates and the efficacy of the vaccine. In the 22-year-old patient with a pneumonia incidence of 0.3/1000, the vaccine would need to be > 71 percent effective for the vaccination strategy to cost less than $50,000/QALY gained. At an incidence of 0.4/1000, the threshold efficacy is 53 percent, whereas at 0.5/1000 it is 43 percent. In the 35-year-old patient where the incidence of pneumococcal pneumonia is higher (0.85/1000), the vaccine would be cost-effective with an efficacy as low as 30 percent.

CONCLUSIONS

Use of the S. pneumoniae vaccine in young adults would provide modest reductions in pneumonia-associated morbidity and mortality. Vaccination of young adults is moderately expensive unless vaccine efficacy is above 50% to 60%. In 35-year-old adults, use of the vaccine is cost-effective even with moderate efficacy.

An intervention to improve antibiotic delivery and sputum procurement in patients hospitalized with community-acquired pneumonia

STUDY OBJECTIVES

To determine if an educational intervention targeting emergency department (ED) and medicine staff could successfully decrease the time to antibiotic delivery (door-to-drug delivery time [DDD]) for patients admitted through the ED with community-acquired pneumonia (CAP).

DESIGN

Prospective, multidisciplinary team-based educational project. Demographics, outcomes, and processes of care including DDD and sputum procurement for patients with CAP were determined during a baseline period and compared to the same parameters for patients with CAP presenting after the educational intervention was administered to ED and medicine staff.

SETTING

Barnes-Jewish Hospital, a large Midwest teaching institution affiliated with the Washington University School of Medicine.

PATIENTS

Consecutive adult patients admitted through the ED with CAP.

INTERVENTION

Multidisciplinary in-service education administered to ED physicians and nurses, and medicine housestaff, which emphasized the importance of rapid antibiotic delivery and procurement of preantibiotic expectorated sputum.

RESULTS

Mean DDD improved from 413 to 291 min (p = 0.02), with more patients receiving antibiotics in the ED (46% vs 69%; adjusted odds ratio [OR], 2.3; 95% confidence interval [CI], 1.0 to 4.9). Sputum procurement improved from 11.5 to 25.4% (adjusted OR, 3.3; 95% CI, 1.1 to 9.9). There were no observed differences for inpatient mortality or length of stay.

CONCLUSION

This multidisciplinary team intervention significantly improved the time to initiation of antibiotics and procurement of sputum for patients with CAP.

Aspectos relevantes da interface entre diabetes mellitus e infecção

O diabetes mellitus (DM) é uma doença de alta prevalência nas sociedades modernas, na maioria das vezes com tratamento inadequado ou ausente. Apesar de geralmente considerado como fator de risco independente para ocorrência e gravidade de infecções em geral, o DM não apresenta evidência clínica forte de sua relação com infecção. Observa-se, porém, uma maior ocorrência de certas infecções em pacientes com DM, com curso menos favorável para algumas delas. Há também tipos de infecção quase exclusivos de pacientes com DM. Experimentalmente, observa-se depressão da atividade dos neutrófilos, menor eficiência da imunidade celular, alteração dos sistemas antioxidantes e menor produção de interleucinas. Com relação às infecções comuns, as que envolvem o trato respiratório não têm comprovadamente maior gravidade em pacientes com DM, exceção feita ao pneumococo - por isso a recomendação para sua vacinação contra S. pneumoniae e influenza. Quanto ao trato urinário, há maior ocorrência de bacteriúria assintomática em mulheres com DM, com maiores índices de pielonefrite, necrose papilar, abscesso perinéfrico, pielonefrite xantogranulomatosa, e cistite e pielonefrite gangrenosas. Periodontite e infecções de partes moles são também mais comuns no DM. Cada tipo de infecção é associado a germes típicos, e seu conhecimento é fundamental para um tratamento inicial adequado. As infecções quase exclusivas de pacientes com DM incluem otite externa maligna, mucormicose rinocerebral, colecistite gangrenosa e o somatório de alterações que caracterizam o pé diabético. O conhecimento destas infecções assume maior importância por requererem freqüentemente uma abordagem multidisciplinar, envolvendo endocrinologistas, infectologistas, cirurgiões vasculares e nefrologistas, dentre outros.

3: Community-acquired pneumonia

Community-acquired pneumonia is caused by a range of organisms, most commonly Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydia pneumoniae and respiratory viruses. Chest x-ray is required for diagnosis. A risk score based on patient age, coexisting illness, physical signs and results of investigations can aid management decisions. Patients at low risk can usually be managed with oral antibiotics at home, while those at higher risk should be further assessed, and may need admission to hospital and intravenous therapy. For S. pneumoniae infection, amoxycillin is the recommended oral drug, while benzylpenicillin is recommended for intravenous use; all patients should also receive a tetracycline (eg, doxycycline) or macrolide (eg, roxithromycin) as part of initial therapy. Flucloxacillin or dicloxacillin should be added if staphylococcal pneumonia is suspected, and gentamicin or other specific therapy if gram-negative pneumonia is suspected; a third-generation cephalosporin plus intravenous erythromycin is recommended as initial therapy for severe cases. Infections that require special therapy should be considered (eg, tuberculosis, melioidosis, Legionella, Acinetobacter baumanii and Pneumocystis carinii infection).

Appropriate use of antimicrobials for drug-resistant pneumonia: focus on the significance of beta-lactam-resistant Streptococcus pneumoniae

The beta-lactam antibiotics (penicillins and cephalosporins) are commonly prescribed for the treatment of community-acquired pneumonia. However, Streptococcus pneumoniae, the most common etiologic agent of community-acquired pneumonia, has become increasingly resistant to beta-lactams over the past decade. The results of several studies suggest that penicillins remain effective for streptococcal pneumonia when the infecting pathogen has a minimal inhibitory concentration (MIC) </=2 microgram/mL, presumably because the pharmacokinetic and pharmacodynamic parameters associated with current dosing regimens are still sufficient. However, when the MIC >/=4 microgram/mL, increased rates of mortality (for patients who survive their first 4 days of hospitalization) may occur. Currently, 3.5%-7.8% of S. pneumoniae clinical isolates have MICs that fall in this latter class, but these rates may rise in the future. The clinical relevance of in vitro resistance may be related to at least 3 factors: concordance of antimicrobial therapy, severity of illness, and virulence.

[Community-acquired pneumonia in the elderly: prognostic factors]

The incidence and mortality rates of community-acquired pneumonia are far higher in the elderly than among younger populations. However, the explanation may lie in the presence of comorbidity rather than in age itself. We performed a retrospective study of 226 patients over the age of 65 years who were admitted to our hospital with a diagnosis of community-acquired pneumonia over a period of 36 months, with the objective of identifying factors predicting mortality and to describe clinical features. The patients' mean age was 78.71 (65-96) years. One hundred forty-two were men (63%) and 84 were women (37%). Upon admission, 27.4% showed signs of altered mental state. The crude mortality rate was 20.8%. Multivariate analysis demonstrated the following independent risk factors associated with higher mortality: serum creatinine > 1.2 mg/dL (RR = 13.93; 95% CI 8.14-16.08); patient previously bedridden (RR = 5.73; 95% CI 3.41-6.79), PaO2/FiO2 < 200 (RR = 5; 95% CI 2.67-6.62) and neoplastic disease (RR = 4.08; 95% CI 1.96-5.24). The presence of chest pain was associated with a lower risk of mortality (RR = 0.11; 95% CI 0.01-0.54). Age itself was not a risk factor. We conclude that pneumonia in the elderly requires hospitalization and that it commonly presents with severe symptoms and high risk of mortality. Risk factors such as those identified in this study may help in the diagnosis and treatment of patients requiring special care.

Respiratory rate measurement in adults--how reliable is it?

Measurement of respiratory rate (RR) is essential in the evaluation of respiratory disorders. However, the variability in RR measurement in adults has never been adequately assessed. Respiratory rate was measured twice in 245 patients; the two measurements were performed by the same observer in 137 patients, by different observers in 58 patients and simultaneously by different observers in 50 patients. The mean (SD) difference between the first and second measurements was 0.03 (3); 95% limits of agreement-4.86-4.94 breaths min(-1), -5.7-5.7 breaths min(-1), and -4.2 to 4.4 breaths min(-1) for the same observer, different observer and simultaneous observer groups, respectively. The difference in RR measurements did not vary with RR. In conclusions on average, there is very good agreement between observers in RR measurement. Inter-observer variability may account for a difference of up to 6 breaths min(-1). This is relevant when applying clinical prediction rules based on threshold RR values.

Cost-effective approaches to the treatment of community-acquired pneumonia in the era of resistance

Community-acquired pneumonia (CAP) infects upwards of four million people in the US each year, of which 20% require subsequent hospitalisation. Consequently, it is a large contributor to excessive healthcare resource consumption and cost. Since the aetiology of CAP is not identified in a majority of patients, treatment is often empiric, aimed at the most common causes, Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and the atypical pathogens (Mycoplasma pneumoniae, Chlamydia pneumoniae and Legionella pneumophila). A variety of pharmaceutical agents exist for the treatment of CAP, most notably the cephalosporin and penicillin derivatives, the macrolide/azalide antibacterials, the newer tetracyclines, and most recently the respiratory fluoroquinolones. Choosing an agent is usually related to issues such as patient compliance, adverse event profiles, and the presence of resistance. Of these, resistance seems to be the main factor today. S. pneumoniae, the most common cause of CAP, is steadily acquiring resistance to a majority of the currently available antibacterials, thus further increasing costs due to prolonged hospitalisation, treatment of relapses and the use of more expensive antibacterials. Understanding and maximising the pharmacodynamic properties of the available antibacterials will not only prevent the emergence of resistance, thus prolonging their clinical utility, but also reduce the costs associated with treating the infection through rapid symptom improvement and earlier patient discharge. Numerous methods for reducing costs in patients with bacterial infections are documented in the literature and can be applied to CAP. Choosing monotherapy instead of combination therapy can reduce costs associated with the administration of the antibacterial. Agents with longer half-lives allow for once-daily administration, which in turn, leads to improved compliance, successful outcomes, and decreased costs. Administering antibacterials to maximise their pharmacodynamics, such as with continuous infusion of beta-lactams, reduces the amount of drug needed in addition to savings associated with administration and supplies. Finally, transitioning patients to oral therapy as soon as they are clinically stable can significantly reduce the length of hospital stay, which is the major contributing factor of healthcare costs. The use of a clinical pathway in an institution is the most effective way to apply these cost-saving approaches in the treatment of CAP. These pathways should be specific to each institution, thus considering the resistance rates in the area and encouraging the use of the most active, cost-effective agents to produce rapid, positive clinical outcomes.

Bronchopulmonary disposition of the ketolide telithromycin (HMR 3647)

Telithromycin (HMR 3647) is the first member of a new family of antimicrobials, the ketolides, developed specifically for the treatment of community-acquired respiratory tract infections. Telithromycin has proven in vitro activity against both common and atypical respiratory tract pathogens. The penetration of telithromycin into bronchopulmonary tissues and subsequent elimination from these sites were evaluated in four groups (groups A, B, C, and D) of six healthy male subjects who received telithromycin at 800 mg once daily for 5 days. Subjects in groups A, B, C, and D underwent fiberoptic bronchoscopy and bronchoalveolar lavage 2, 8, 24, and 48 h after receipt of the last dose, respectively. The concentration of telithromycin in the alveolar macrophages, epithelial lining fluid (ELF), and plasma was determined by the agar diffusion method with Bacillus subtilis ATCC 6633 as the test organism. The concentration of telithromycin in alveolar macrophages markedly exceeded that in plasma, reaching up to 146 times the concentration in plasma 8 h after dosing (median concentration, 81 mg/liter). Telithromycin was retained in alveolar macrophages 24 h after dosing (median concentration, 23 mg/liter), and it was still quantifiable 48 h after dosing (median concentration, 2.15 mg/liter). Telithromycin median concentrations in ELF also markedly exceeded concentrations in plasma (median concentration in ELF, 3.7 mg/liter 8 h after dosing). Telithromycin achieves high and sustained concentrations in ELF and in alveolar macrophages, while it maintains adequate levels in plasma, providing an ideal pharmacokinetic profile for effective treatment of community-acquired respiratory tract infections caused by either common or atypical, including intracellular, respiratory tract pathogens.

Optimisation of antimicrobial therapy using pharmacokinetic and pharmacodynamic parameters

To understand the relationship between drug dose and efficacy, pharmacokinetic (PK) and pharmacodynamic (PD) characteristics need to be integrated. Patterns of antimicrobial activity fall into one of two major patterns: time-dependent killing and concentration-dependent killing. Time-dependent killing is characteristic of many antibiotic classes, such as beta-lactams and macrolides, and seeks to optimise the duration of exposure of a pathogen to an antimicrobial. The major PK/PD parameter correlating with efficacy of time-dependent antimicrobials is the serum concentration present for 40-50% of the dosing interval, and this concentration is the susceptibility limit or breakpoint for the dosing regimen used. The second pattern, concentration-dependent killing, seeks to maximise antimicrobial concentration and is seen with aminoglycosides, quinolones and azalides. The major PK/PD parameter correlating with efficacy of these agents is the 24-h area under the curve to MIC ratio, which should be > or =25 for less severe infections or in immunocompetent hosts, and > or =100 in more severe infections or in immunocompromised hosts. PK/PD breakpoints for concentration-dependent agents can therefore be calculated from the formula AUC divided by 25. This enables development of PK/PD breakpoints based on the above parameters for time- and concentration-dependent agents for defined dosing regimens. For an antimicrobial to be useful empirically, the MIC90s of the agent against the common pathogens responsible for the disease being treated should be below the PK/PD breakpoint. This is particularly important for oral dosing regimens for treating emerging resistant respiratory tract pathogens, where efficacy against the predominant pathogens, Streptococcus pneumoniae and Haemophilus influenzae, is required.

[Community acquired pneumonia in patients older than 60 years. Incidence of atypical agents and clinical-radiological progression]

BACKGROUND

Seventy five patients older than 60 years with a community acquired pneumonia followed up in an outpatient clinic, were prospectively studied in order to determine the incidence of atypical agents, clinical-radiological characteristics, progression and the differences with pneumonia in younger patients.

METHOD

Clinical-radiological evaluation protocols were activated in the first visit and in two subsequent controls. Etiological diagnosis was made by means of serology (in the first visit and three weeks later).

RESULTS

Initially, 85 patients older than 60 years were included of which 75 non hospitalized were fully followed up. Also, in the comparative study, 216 outpatient clinic patients 60 years old or younger were followed up during the same period. In the first group the frequency of atypical agents was 33.3%. The most frequently isolated bacteria was Coxiella burnetii (13.3%)followed by virus and Legionella pneumophila. No case of Mycoplasma pneumoniae was diagnosed. The most frequent radiological onset was alveolar infiltrate (85%). The comparative study between the two populations (older or younger than 60 years), found few clinical differences (dyspnea more frequent in older,feverish chill in younger) and auscultation (crackles more frequent in older). We did not find differences remaining clinical-radiological or laboratory data. Most patients presented a favourable clinical and radiological progression. Only 2 patients needed hospital admission (2.7%).

CONCLUSIONS

In outpatient clinic patients older than 60 years with community acquired pneumonia a high number of atypical agents have been found. The clinical-radiological evolution was satisfactory for most of them. Age was not a decisive element in determining hospital admissions.

Evaluation of a rapid immunochromatographic test for detection of Streptococcus pneumoniae antigen in urine samples from adults with community-acquired pneumonia

Streptococcus pneumoniae is the most common cause of community-acquired pneumonia but is undoubtedly underdiagnosed. Isolation of S. pneumoniae from blood is specific but lacks sensitivity, while isolation of S. pneumoniae from sputum may represent colonization. We evaluated a new immunochromatographic test (NOW S. pneumoniae urinary antigen test; Binax, Portland, Maine) that is simple to perform and that can detect S. pneumoniae antigen in urine within 15 min. Urine samples from 420 adults with community-acquired pneumonia and 169 control patients who did not have pneumonia were tested. Urine from 315 (75%) of the pneumonia patients and all controls was tested both before and after 25-fold concentration, while the remaining 105 samples were only tested without concentration. S. pneumoniae urinary antigen tests were positive for 120 (29%) patients with pneumonia and for none of the controls. Of the urine samples tested with and without concentration, 96 were positive, of which 6 were positive only after concentration. S. pneumoniae antigen was detected in the urine from 16 of the 20 (80%) patients with blood cultures positive for S. pneumoniae and from 28 of the 54 (52%) patients with sputum cultures positive for S. pneumoniae. The absence of S. pneumoniae antigen in the urine from controls suggests that the specificity is high. Concentration of urine prior to testing resulted in a small increase in yield. The NOW S. pneumoniae urinary antigen test should be a useful adjunct to culture for determining the etiology of community-acquired pneumonia in adults.

An emergency department-based randomized trial of nonbronchoscopic bronchoalveolar lavage for early pathogen identification in severe community-acquired pneumonia

STUDY OBJECTIVES

Many patients with community-acquired pneumonia are treated empirically without an aggressive search for causative pathogens, an approach adopted largely because of the costs and difficulties encountered during efforts to identify the causative organisms. Blood and sputum cultures are not sensitive, and the more invasive techniques of bronchoscopy and lung biopsy are generally time consuming and not cost-effective. The technique of nonbronchoscopic bronchoalveolar lavage (BAL) has been shown to accurately diagnose the causes of nosocomial pneumonia. The purpose of this study was to determine whether an emergency department-based BAL protocol would lead to more frequent isolation of pneumonia pathogens and result in more changes to tailored antibiotic therapy in comparison with standard care.

METHODS

We studied all adult patients admitted with a diagnosis of pneumonia who were tracheally intubated and who had obtainable familial consent in the ED of an urban county hospital from March 1998 to October 1999. Exclusions included antibiotic use within the past 5 days, pneumothorax, hemoptysis, or persistent hypoxia using 100% oxygen. Patients were randomized to standard care versus standard care plus BAL. Blood culture specimens were drawn from all patients before the initiation of antibiotics. All other diagnostic tests were ordered at the discretion of treating physicians. BAL fluid, sputum, and blood culture specimens were tracked, and patient antibiotic course was followed to assess any change in regimen.

RESULTS

Twenty-six of 64 patients evaluated for study participation met all eligibility criteria; 14 patients received standard care, and 12 patients received standard care plus BAL. Pneumonia pathogens were identified in 10 (83.3%) of 12 patients in the BAL group and in 4 (28.6%) of 14 patients in the standard care group (P =.007). Comparing BAL versus non-BAL groups, there was no significant difference in the likelihood of overall antibiotic regimen changes (P =.149), but there was a difference with regard to antibiotic changes made in patients with positive culture test results (P =.026). No major complications occurred with BAL catheterizations.

CONCLUSION

ED-based BAL catheterization allows for early identification of pathogens in severe community-acquired pneumonia, which leads to changes in antibiotic therapy.

Adherence to ATS guidelines for hospitalized patients with community-acquired pneumonia

OBJECTIVE

To compare outcomes of care and antibiotic utilization for community-acquired pneumonia (CAP) throughout a group of not-for-profit hospitals.

METHODS

A retrospective chart review of patients from community hospitals with a diagnosis of pneumonia at discharge admitted from December 1997 to May 1998. Data were collected based on American Thoracic Society (ATS) criteria.

RESULTS

Medical records of 330 patients were reviewed; mortality was 7%. Using ATS guidelines, 51 (15.5%) patients were not treated with recommended antimicrobial therapy. Of these patients, 14 had nonsevere cases of CAP and 37 cases were severe. Factors found to be associated with in-hospital mortality included nonadherence to ATS guidelines (OR 4.46; 95% CI 1.38 to 14.43), decreased urine output (OR 7.72; 95% CI 1.70 to 35.04), and increasing age (OR 1.06; 95% CI 1.01 to 1.12). Significant predictors of length of stay (LOS) included age, nonadherence to ATS criteria, suspected aspiration, discharge status, low pulse oximetry on admission, decreased urine output, use of vasopressor medications, and interstitial lung disease; More than 80% of patients had at least one culture performed, but only 27.5% of these cultures were positive. The most cpmmonly prescribed antibiotic was cefuroxime injection, representing 25% of the antibiotic orders.

CONCLUSIONS

Patients with CAP treated inconsistently with ATS guidelines had a 4.46-d higher risk of inpatient mortality and had significantly longer LOS.

Estudo de casos hospitalizados por pneumonia comunitária no período de um ano

Introdução: Apesar dos avanços obtidos nos métodos propedêuticos, cerca de 50% dos casos de pneumonia adquirida na comunidade não têm sua etiologia esclarecida, inclusive os hospitalizados. Apesar disso, a terapêutica adequada proporciona baixas taxas de mortalidade na maioria dos casos. Objetivos: Descrever a epidemiologia, formas de apresentação, o rendimento dos testes diagnósticos, a permanência hospitalar, a morbidade e mortalidade de 42 pacientes consecutivos, internados para tratamento de PAC. Métodos: Foram incluídos pacientes com quadro clínico compatível com PAC, opacidade radiológica pulmonar recente e com dois itens entre febre, tosse produtiva e leucocitose. A solicitação de exames complementares obedeceu à necessidade de cada caso. Resultados: Dos 42 pacientes, com idade de 64,7 ± 16,8 anos, 27 (64,3%) masculinos, 27 (64%) apresentavam co-morbidades. Dezessete (40,5%) estavam em uso de antibióticos à admissão. Pneumonia grave ocorreu em oito casos (19%); não houve diferença quanto à gravidade (p = 0,57) e permanência hospitalar (p = 0,25) entre os grupos > de 60 ou <= de 60 anos. A permanência hospitalar média foi de 14,3 ± 7,6 dias. Diagnóstico etiológico definitivo foi obtido em três casos: Legionella sp em dois, S. aureus em um caso. Em 31 (74%), manteve-se o antibiótico inicial; em 11 (26%) houve troca, seis (54,5%) devido à má resposta clínica e cinco (45,5%) devido ao resultado microbiológico. Hemoculturas foram feitas em 16 casos (38%), positivas em apenas um (6,3%). Nove amostras de escarro (9/22, 41%) foram validadas. Ocorreu um óbito (2,4%), por pneumonia grave, em um paciente com neoplasia. Conclusões: O diagnóstico etiológico em PAC, mesmo em internados, é obtido em uma minoria de casos, contribuindo para isso o uso concorrente de antibióticos. A terapêutica empírica adequada proporciona baixas taxas de mortalidade. Os testes diagnósticos devem ser empregados de maneira individualizada.

What factors influence physicians' decisions to switch from intravenous to oral antibiotics for community-acquired pneumonia?

OBJECTIVE

One of the major factors influencing length of stay for patients with community-acquired pneumonia is the timing of conversion from intravenous to oral antibiotics. We measured physician attitudes and beliefs about the antibiotic switch decision and assessed physician characteristics associated with practice beliefs.

DESIGN

Written survey assessing attitudes about the antibiotic conversion decision.

SETTING

Seven teaching and non-teaching hospitals in Pittsburgh, Pa.

PARTICIPANTS

Three hundred forty-five generalist and specialist attending physicians who manage pneumonia in 7 hospitals.

MEASUREMENTS AND RESULTS

Factors rated as "very important" to the antibiotic conversion decision were: absence of suppurative infection (93%), ability to maintain oral intake (79%), respiratory rate at baseline (64%), no positive blood cultures (63%), normal temperature (62%), oxygenation at baseline (55%), and mental status at baseline (50%). The median thresholds at which physicians believed a typical patient could be converted to oral therapy were: temperature < or =100 degrees F (37.8 degrees C), respiratory rate < or =20 breaths/minute, heart rate < or =100 beats/minute, systolic blood pressure > or =100 mm Hg, and room air oxygen saturation > or =90%. Fifty-eight percent of physicians felt that "patients should be afebrile for 24 hours before conversion to oral antibiotics," and 19% said, "patients should receive a standard duration of intravenous antibiotics." In univariate analyses, pulmonary and infectious diseases physicians were the most predisposed towards early conversion to oral antibiotics, and other medical specialists were the least predisposed, with generalists being intermediate (P <.019). In multivariate analyses, practice beliefs were associated with age, inpatient care activities, attitudes about guidelines, and agreeableness on a personality inventory scale.

CONCLUSIONS

Physicians believed that patients could be switched to oral antibiotics once vital signs and mental status had stabilized and oral intake was possible. However, there was considerable variation in several antibiotic practice beliefs. Guidelines and pathways to streamline antibiotic therapy should include educational strategies to address some of these differences in attitudes.

Community-acquired pneumonia in patients requiring hospitalization

OBJECTIVE

This study aimed to investigate the microbial aetiology of community-acquired pneumonia (CAP) in patients requiring hospitalization.

METHODOLOGY

A prospective study of consecutive non-immunocompromised patients aged 12 years and above admitted with CAP from August 1997 to May 1999 was undertaken.

RESULTS

Of 127 patients hospitalized for CAP, an aetiological diagnosis was achieved in 53 cases (41.7%). Klebsiella pneumoniae was the most frequently isolated pathogen and caused 10.2% of all the cases, followed by Streptococcus pneumoniae (5.5%), Haemophilus influenzae (5.5%), Mycoplasma pneumoniae (3.9%) and Pseudomonas aeruginosa (3.9%). Gram-negative bacilli were significantly more frequently identified in patients aged 60 years or older and in patients with comorbid illnesses. Twelve of 13 patients who died from CAP had other comorbid illnesses compared to 63 of 114 patients who survived (P = 0.014). Three of eight bacteraemic patients died compared with 10 of 119 non-bacteraemic patients (P = 0.035).

CONCLUSIONS

The microbiology of CAP in patients requiring hospitalization in Malaysia appears to be different from that in Western countries. Gram-negative bacilli were more frequently isolated in older patients and in those with comorbidity. Mortality from CAP is more likely in patients with comorbidity and in those who are bacteraemic.

Rationale for treating community-acquired lower respiratory tract infections with amoxicillin/sulbactam combination through pharmacodynamic analysis in the setting of aminopenicillin-resistant organisms

In order to establish a rationale for treating community-acquired lower respiratory tract infections, we assess here the pharmacodynamics of amoxicillin/sulbactam, 500mg/500mg, a formulation marketed in Argentina since 1988 and currently available in 17 countries, against the major pathogens, in comparison with that of a novel formulation (875mg/125mg, see J Chemother 2000; 12: 223-227). In time-kill studies, both bactericidal and inhibitory activity were seen in the 1.5- and 6-h sera, obtained from 12 volunteers after a single oral dose, against both a penicillin-susceptible and an -intermediate Streptococcus pneumoniae strain, as well as against Moraxella catarrhalis and a beta-lactamase-negative Haemophilus influenzae strain. Only the 1.5-h sera proved bactericidal against a penicillin-resistant S. pneumoniae strain (MIC, 2 microg/ml) and a beta-lactamse-positive H. influenzae isolate. This study suggests that amoxicillin/sulbactam (500mg/500mg) is still a suitable option for treating community-acquired lower respiratory tract infections, allowing a b.i.d. dosing schedule. Caution should be taken with pneumonia caused by beta-lactamase-positive H. influenzae or penicillin-resistant (MIC > or =2 microg/ml) S. pneumoniae isolates. Either shorter dosing intervals (t.i.d.) or a higher amoxicillin content in the formulation (i.e. 875 mg) may be required in these situations.

Clinical policy for the management and risk stratification of community-acquired pneumonia in adults in the emergency department

This clinical policy represents an approach that emphasizes key clinical information to determine the severity of CAP. By using this approach, a determination of whether the patient can be treated as an outpatient or inpatient may be made. Recommendations about the utility of ancillary studies and the use of antibiotics are also given. As more of the questions are answered through controlled studies, an evidence-based approach to this problem will become increasingly important in improving the outcome of patients with CAP.

Clinical evaluation of the management of community-acquired pneumonia by general practitioners in France

STUDY OBJECTIVES

To evaluate the management of community-acquired pneumonia (CAP) by general practitioners (GPs) in terms of clinical efficiency and adherence to official recommendations.

DESIGN

Prospective cohort study.

SETTING

Community-based study from 11 French counties.

PATIENTS

Adult patients clinically suspected of having CAP who were seen by GPs were included after confirmation of the presence of an infiltrate on chest radiographs.

INTERVENTION

The management of the patients was left to the discretion of the GP.

MEASUREMENTS AND RESULTS

One hundred thirty patients were included in the study, and 13 patients (10%) were immediately hospitalized because of the severity of the pneumonia. The remaining 117 patients were treated as outpatients: 108 of 117 patients (92%) were cured, and 9 patients were subsequently hospitalized because of the failure of ambulatory treatment. Diagnostic error (n = 6) rather than antibiotic failure (n = 3) was the most frequent cause of the failure of ambulatory treatment. Only 40% of the patients received an initial antibiotic treatment that was in agreement with French recommendations. However, the rate of antibiotic failure leading to hospitalization was low (3 of 117 patients; 2.6%) and similar for patients treated or not according to recommendations (p > 0.5). Overall, five patients (4%) died; all deaths occurred during hospitalization and were related to the severity of the underlying disease but not to the choice of antibiotic treatment.

CONCLUSIONS

The management of CAP by GPs was clinically effective despite a poor adherence to official recommendations. Our results suggest that adequate assessment of severity rather than adherence to recommendations for antibiotic treatment had an impact on clinical outcome of CAP managed by GPs.

Initial risk class and length of hospital stay in community-acquired pneumonia

The total medical costs of community-acquired pneumonia are directly related to the costs of hospital admission and length of stay. The aim of the present study was to evaluate the reasons for prolonged duration of stay in patients stratified in five risk classes for death, and to identify factors associated with prolonged stay. The study population consisted of 295 patients. According to lower (classes I, II, III) or to higher (classes IV, V) risk, the target duration of hospitalization was set at 5 and 7 days, respectively. The causes of prolonged hospitalization were classified as pneumonia-related, complications, unstable comorbid diseases and nonclinical factors. The overall percentage of patients with appropriate duration of hospitalization was 32%. Causes of prolonged hospitalization were related mainly to pneumonia (32%) from all risk classes. Morbid complications and instability of the underlying illness were greater in class V patients. Nonclinical factors were present in 29.5% of cases. Hypoxaemia, anaemia, hypoalbuminaemia, and complications appearing before 72 h were associated with prolonged hospitalization. The cause of prolonged hospitalization of patients with community-acquired pneumonia is multifactorial, depending mainly on pneumonia and comorbid conditions but there is a large number of unnecessary hospitalization days that could be reduced by improving the efficiency of hospital care.

Diagnosis and management of respiratory tract infections for the primary care physician

Respiratory tract infections cause nearly half of deaths owing to infectious disease in the United States. This article has discussed the management of several common respiratory tract infections, with an emphasis on appropriate diagnosis and use of antimicrobial agents. Understanding the cause of various respiratory tract infections enables primary care physicians to avoid unnecessary antibiotic use, decreasing adverse effects owing to medications and preventing the rise in antimicrobial resistance.

The efficacy of an antibiotic protocol for community-acquired pneumonia

OBJECTIVE

To assess the efficacy of an antibiotic protocol to avoid empirical use of third-generation cephalosporins in community-acquired pneumonia (CAP).

DESIGN AND SETTING

Retrospective case review of patients with CAP one year after implementing the protocol. Comparison was made with patients with CAP treated at a metropolitan tertiary referral hospital (where use of third-generation cephalosporins was common).

PARTICIPANTS

86 patients (district hospital with an antibiotic protocol) and 72 patients (metropolitan tertiary referral hospital), January - June 1999.

OUTCOME MEASURES

Rate of staff adherence to the protocol; patient characteristics associated with poor protocol adherence; demographic and prognostic features of both groups at presentation; duration of intravenous therapy, time to defervescence, length of stay; inpatient mortality rates; and drug cost savings per patient treated according to the protocol.

RESULTS

Overall protocol adherence rate was 60%. Patients with penicillin allergy were significantly less likely to receive treatment according to the protocol (P<0.001). At the district hospital, patients were generally older and taking more regular medications. Patients at each hospital had similar prognostic factors and demographic features at presentation. Inhospital mortality (P=0.92; 95% CI, -0.08 to 0.07), duration of fever (P=0.57) and length of stay (P=0.78) were not significantly different between patients treated empirically with penicillin and those treated empirically with third-generation cephalosporins. Treating a patient according to the protocol saved an average of $77.44 in drug costs.

CONCLUSION

One year after implementation, our protocol for treating CAP is proving efficacious, although levels of adherence could improve.

An update on community-acquired pneumonia in adults

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality, despite effective therapies. Guidelines for CAP management vary widely in their approach. Resistance of S pneumoniae to penicillins and other antibiotics has prompted evaluation of the new fluoroquinolones.

Community-acquired pneumonia. A prospective outpatient study

We initiated a prospective study with a group of practitioners to assess the etiology, clinical presentation, and outcome of community-acquired pneumonia in patients diagnosed in the outpatient setting. All patients with signs and symptoms suggestive of pneumonia and an infiltrate on chest X-ray underwent an extensive standard workup and were followed over 4 weeks. Over a 4-year period, 184 patients were eligible, of whom 170 (age range, 15-96 yr; median, 43 yr) were included and analyzed. In 78 (46%), no etiologic agent could be demonstrated. In the remaining 92 patients, 107 etiologic agents were implicated: 43 were due to "pyogenic" bacteria (39 Streptococcus pneumoniae, 3 Haemophilus spp., 1 Streptococcus spp.), 39 were due to "atypical" bacteria (24 Mycoplasma pneumoniae, 9 Chlamydia pneumoniae, 4 Coxiella burnetii, 2 Legionella spp.), and 25 were due to viruses (20 influenza viruses and 5 other respiratory viruses). There were only a few statistically significant clinical differences between the different etiologic categories (higher age and comorbidities in viral or in episodes of undetermined etiology, higher neutrophil counts in "pyogenic" episodes, more frequent bilateral and interstitial infiltrates in viral episodes). There were 2 deaths, both in patients with advanced age (83 and 86 years old), and several comorbidities. Only 14 patients (8.2%) required hospitalization. In 6 patients (3.4%), the pneumonia episode uncovered a local neoplasia. This study shows that most cases of community-acquired pneumonia have a favorable outcome and can be successfully managed in an outpatient setting. Moreover, in the absence of rapid and reliable clinical or laboratory tests to establish a definite etiologic diagnosis at presentation, the spectrum of the etiologic agents suggest that initial antibiotic therapy should cover both S. pneumoniae and atypical bacteria, as well as possible influenza viruses during the epidemic season.

[Prospective study of 221 community acquired pneumonias followed up in an outpatient clinic. Etiology and clinical-radiological progression]

BACKGROUND

All the community acquired pneumonia followed up in an outpatient clinic were prospectively studied in order to determine: etiology, clinical-radiological characteristics and its progression with diagnostic and therapeutic protocols.

PATIENTS AND METHOD

We arranged clinical evaluation protocols, etiological diagnosis by means of serology (in the first visit and three weeks later); and when necessary, by means of fiberbronchoscopy (protected microbiological brush), as well as clinical and radiological progression (up to three visits) after empirical treatment.

RESULTS

Initially, 240 patients were included, of which 221 were fully followed up. Etiological diagnosis was obtained in 86 patients (39%). The bacteria most frequently isolated was Coxiella burnetii (12.2%), followed up Mycoplasma pneumoniae and Legionella pneumophila. Two cases of Strepcococus pneumoniae were diagnosed. The most frequent radiological onset was alveolar infiltrate (86%). The initial empiric treatment were macrolids (71%) or second generation cephalosporines (22%). Most patients presented a favourable clinical and radiological progression. Only 2 patients needed admission to the hospital (< 1%).

CONCLUSIONS

In community acquired pneumonias studied in our outpatient clinic we found a high number of "atypical" agents. Treatment with macrolids or second generation cephalosporines are appropriate for these patients.

Defining prognostic factors in the elderly with community acquired pneumonia: a case controlled study of patients aged > or = 75 yrs

Severity assessment in the elderly with community acquired pneumonia (CAP) may be different compared with younger patients. In particular, age per se may not be of prognostic significance in older patients. A case-control study in 158 patients aged > or = 75 yrs with CAP was conducted to determine the factors associated with in-hospital mortality. Cases were drawn from all patients aged > or = 75 yrs with CAP who died in 1997 in five hospitals in the mid-Trent region of the UK (Nottingham City Hospital, University Hospital Nottingham, Derby Royal Infirmary, Derby City General Hospital and Kings Hill Hospital). Controls were randomly selected from survivors also aged > or = 75 yrs. Factors associated with mortality were identified following a review of the medical casenotes and the contribution of these factors to mortality was determined using multivariate analysis. Absence of fever, tachycardia and chest radiograph features of bilateral involvement or an effusion were independently associated with mortality on multivariate analysis. The British Thoracic Society (BTS) severity rule was 50% sensitive and 64% specific in predicting death while the modified BTS rule displayed 67% sensitivity and 58% specificity. Age was not significantly associated with mortality in this group of patients aged > or = 75 yrs. Similarly, the clinical features employed in the British Thoracic Society rule, namely respiratory rate, diastolic blood pressure and blood urea, were not of prognostic significance and the rule itself performed poorly. The modified British Thoracic Society rule performed better.

Clinical utility of the new fluoroquinolones for treating respiratory and urinary tract infections

Increasing antimicrobial resistance among most common urinary and respiratory tract pathogens has been the catalyst for the development of fluoroquinolones that are effective against these prevalent resistant organisms. Important attributes of the newly developed fluoroquinolones include once-daily dosing, maintained extensive tissue penetration and high oral bioavailability added to targeted antibacterial activities, all pharmacodynamic characteristics that may reduce the need for parenteral therapy or prevent patients being hospitalised. Some fluoroquinolones also offer same-dose bioequivalency between iv. and oral formulations, a feature that allows iv.-to-oral dosing (step-down or 'switch' therapy) without the need for dosage adjustments. These features suggest that the newer fluoroquinolones may be near-ideal agents for the empirical treatment of many common infections. This review discusses the efficacy and clinically relevant antimicrobial and pharmacokinetic qualities of the fluoroquinolones in comparison with other agents traditionally used to treat patients with urinary and respiratory tract infections.

[Community-acquired pneumonia requiring hospital admission. A comparison of the clinical management, resource use and prognosis by different medical specialties]

OBJECTIVE

To evaluate whether there are differences regarding therapy, resource use and prognosis of inpatients due to community acquired pneumonia (CAP) in different clinical departments.

METHODS

One-year retrospective study, using the discharge abstract, of all patients aged over 7 years admitted to the general hospital with the diagnosis of CAP. Comparison of the appropriateness of antibiotic therapy, mean hospital stay, use of invasive procedures, intrahospital mortality rate, and readmissions between the different clinical departments.

RESULTS

A total of 511 patients were studied, 154 in Internal Medicine, 197 in Pneumology, 107 in Geriatrics and 53 in other departments, with moderate to severe underlying disease in 50.8%, severity criteria of CAP in 75%, and intrahospital mortality rate of 11.7%. No differences were observed regarding mean stay or appropriateness of antibiotic therapy. Invasive procedures were used most commonly in the Pneumology Department (12% vs 2%-7.5%; p = 0.001). In the Geriatrics Department readmissions were most common (10% vs 1%-4%; p = 0.006) and intrahospital mortality rate (19% vs 8.6%-13.2%; p = 0.029) than in the remaining departments. Intrahospital mortality was associated with a moderate or severe underlying disease, neurologic disease, severity criteria of CAP and ICU admission, and readmissions with a moderate or severe underlying disease.

CONCLUSIONS

There are relevant differences in intrahospital mortality rate and readmissions among patients with CAP in the different clinical departments, which seem to be associated with the underlying disease and the severity of the CAP.

Relationship of Penicillin Resistance to Mortality in Pneumococcal Pneumonia

Clinical management of community-acquired pneumonia (CAP)--and Streptococcus pneumoniae infection in general--are controversial. Multiple sets of guidlines exist. This article reviews CAP, S. pneumoniae infection and drug resistance, the four sets of guidlines currently in use in North America, and the data upon which the agencies establishing those guidlines have based their consclusions, particularly about drug resistance and treatment failures. The article also considers the role of penicillin in the treatment of pneumococcal pneumonia.

Management of patients with infectious diseases in an emergency department observation unit

Pneumonia, cellulitis, and pyelonephritis are discussed in this review because they are the most common infections requiring hospital care, and they all have significant death or complication rates and broad differential diagnoses. They also demonstrate many of the considerations that could be applied to other infections appropriate for OU care. Table 11 lists additional infections that are good candidates for OU care. A key to successful OU management of infection is early consultation with the primary care physicians and appropriate specialists when one is setting up the unit, designing its guidelines, and when treating specific patients. Because individual patient outcomes are not predictable, increasing the absolute numbers treated and successfully discharged from observation can necessarily increase the percentage of OU patients that are hospitalized. In essence, a group who would be hospitalized from the ED is transferred to observation status, where most avoid hospital admission. Because some patients fail to respond, develop complications, or demonstrate alternative diagnoses, many troubles can be avoided when the primary care and specialist physicians have collaborated in the observation treatment decisions. These guidelines have been presented as a starting point. It is clear that more research targeted at this group of patients is required to refine current practice. As for everything else in medicine, there is no doubt that many of the specific recommendations made here will become obsolete in no time.