Adult community-acquired pneumonia in central London

Antimicrobial drug prescribing patterns for community-acquired pneumonia in hospitalized patients: A retrospective pilot study from New Delhi, India

OBJECTIVE

The objective of this study was to determine patterns and frequency of antimicrobial drug use among hospitalized patients with community-acquired pneumonia (CAP).

METHODOLOGY

A retrospective 5 years (April 2007-March 2012) detailed medical record review of patients diagnosed with CAP and discharged to home from Non-Intensive Care Unit respiratory medicine wards of two public hospitals in Delhi.

RESULTS

A total of 261 medical records were analyzed. Over the 5 years, 82.0% (2007-08), 78.6% (2008-09), 59.5% (2009-10), 64.7% (2010-11), and 67.8% (2011-12) patients were prescribed two antimicrobials. In the last two study years, the proportion of patients receiving three antimicrobials increased (from 2.0% to 26.5% and 28.8%), while the proportion receiving monotherapy decreased (from 16.0% to 8.8% and 3.4%). In accordance with guidelines, beta-lactams and macrolides were the two most frequently prescribed antimicrobials (34.1%). However, newer generation beta-lactams were prescribed. A total of 37 patients were prescribed beta-lactam-tazobactam combination preparations. Overall, beta-lactams constituted more than 40% of prescriptions while macrolides were the second most prescribed class. Cephalosporin prescriptions significantly increased (P < 0.01) and penicillin prescriptions significantly decreased over study periods. The prescription of fluoroquinolones also decreased (21.5-6.0%, P < 0.01) and aminoglycoside prescription ranged from 9.7% to 16.4%, over 5 years. Reasons for prescribing three antimicrobials, use of aminoglycosides, or higher-end/reserve antibiotics were not mentioned in the medical records. There were no hospital-specific guidelines for doctors to follow in the treatment of CAP.

CONCLUSIONS

These findings suggest the need for implementing antimicrobial treatment guidelines. Adequate documentation and monitoring of antibiotic use for feedback are also lacking. An antimicrobial stewardship program may offer the most comprehensive solution for appropriate use of antimicrobials.

Serological investigation of pneumonia as it presents to the physician's office

PURPOSE

To define the etiology of pneumonia, using a battery of serological tests, among patients presenting to physicians' offices in Cumberland County, Nova Scotia from July 2, 1989 to July 1, 1990.

METHODS

Patients presenting to their physician's office with symptoms suggestive of pneumonia were invited to participate in the study by completing a questionnaire, having a chest radiograph and providing acute and convalescent phase serum samples. These serum samples were tested for antibodies to Mycoplasma pneumoniae, Coxiella burnetii, Legionella pneumophila, adenovirus, and influenza viruses A and B. Some of the samples were tested for antibodies to Chlamydia pneumoniae.

RESULTS

Seventy-five of the inception cohort of 203 patients had a chest radiograph compatible with pneumonia, a completed questionnaire and acute and convalescent phase serum samples. There were 39 females and 36 males with a mean age of 41.7 years. Twenty-six (35%) were admitted to hospital. The mortality rate was 3%. Forty-five per cent had a diagnosis made by serology: M pneumoniae, 22 (29%); influenza A virus, five (7%); C burnetii, L pneumophila, adenovirus, two (3%) each.

CONCLUSIONS

While it is not possible to generalize about these findings because of ascertainment bias, the data suggest that M pneumoniae is a common cause of pneumonia presenting to a physician's office and that mortality is low in this group of patients.

Guidelines for the management of adult lower respiratory tract infections--full version

This document is an update of Guidelines published in 2005 and now includes scientific publications through to May 2010. It provides evidence-based recommendations for the most common management questions occurring in routine clinical practice in the management of adult patients with LRTI. Topics include management outside hospital, management inside hospital (including community-acquired pneumonia (CAP), acute exacerbations of COPD (AECOPD), acute exacerbations of bronchiectasis) and prevention. Background sections and graded evidence tables are also included. The target audience for the Guideline is thus all those whose routine practice includes the management of adult LRTI.

Pneumonia mortality in a UK general practice population cohort

BACKGROUND

Pneumonia is a common diagnosis in general practice in the United Kingdom and yet there is little known about the short- and long-term prognosis of people with a diagnosis of pneumonia in general practice. We investigated the short- and long-term survival of people with pneumonia diagnosed in general practice as compared to the general population for all ages.

METHODS

This was a general population-based cohort study. Data was obtained from a comprehensive general practice database called The Health Improvement Network (THIN) database which has computerized medical records from 300 general practice surgeries in the United Kingdom. We used Cox regression for our analyses.

RESULTS

For pneumonia cases the 30-day mortality was 18.5% and the 3-year mortality was 30.8%. The equivalent figures for the general population controls were 0.4% and 10.3% respectively. The adjusted hazard ratio (HR) for all-cause mortality (for total follow-up time) in pneumonia cases vs. general population was 4.64 (95% CI 4.35-4.95). For the first 30 days the risk of mortality in cases was 46 times more (adj. HR 45.90, 95% CI 36.80-55.20). Even in the period of follow-up 91 days after diagnosis cases were almost 20% more likely to die compared to general population (adj. HR 1.19, 95% CI 1.08-1.31).

CONCLUSION

People in general practice who have a diagnosis of pneumonia have a markedly increased mortality in the short-term but some increase in mortality persists during longer-term follow-up.

Microbiological profile of community-acquired pneumonia in adults over the last 20 years

OBJECTIVES

To assess any change in the microbiological profile of community-acquired pneumonia (CAP) in our region over the last 20 years.

METHODS

We compared hospital admissions aged between 15 and 74 (n = 61) in Norfolk (UK) for CAP over a 19-month period in 1982-3 (ST1) with all admissions aged over 16 (n = 99) over a 14-month period in 1999-2000 (ST2). Data were collected for ST1 as part of a prospective multicentred research study, in a period of high Mycoplasma pneumoniae activity. ST2 was a prospective study of clinical practice. Chlamydophila species were differentiated in ST2 using whole-cell immunofluorescence.

RESULTS

A microbiological diagnosis was made in 38 (62%) in ST1 compared with 48 (48%) in ST2. Streptococcus pneumoniae remained the most common pathogen (26% in ST1, 25% in ST2). The incidence of M. pneumoniae was 18% in ST1 and 4% in ST2. The proportion of viral pathogens identified was similar: nine (15%) in ST1 and 14 (14%) in ST2. No cases of Chlamydophila pneumoniae were diagnosed in ST2.

CONCLUSIONS

The microbiological profile of CAP in Norfolk (UK) has not changed over the last 20 years and C. pneumoniae is not a frequent pathogen.

Community-acquired pneumonia in ambulatory patients: relative importance of atypical pathogens

The presence of atypical pathogens in community-acquired pneumonia is difficult to diagnose; culture is time-consuming and requires considerable expertise and serological identification may be inaccurate. Nevertheless, the increasing importance of atypical organisms has been recognised in recent years. Variations in aetiology have been detected in different geographical regions and different patient populations. The season of the year may also influence aetiology, and some infections follow a cyclical pattern. When an atypical pathogen is suspected, a macrolide antibiotic is an appropriate choice as, in addition to activity against these organisms, they are usually effective against the Gram-positive and Gram-negative respiratory pathogens implicated in community-acquired pneumonia.

Risk factors for community-acquired pneumonia diagnosed upon hospital admission. British Thoracic Society Pneumonia Study Group

A case-control study of risk factors for community-acquired pneumonia in adults admitted to hospital is reported. Cases were surviving patients (n = 178) admitted to 14 hospitals in England. Controls were individuals (n = 385) randomly selected from the electoral registers of the areas served by the hospitals. The two groups were compared with regard to risk factors for pneumonia using a standardized postal questionnaire. Independent risk factors associated with cases in log-linear regression analysis were age, heart disease (as indicated by congestive heart failure and/or digitalis treatment), lifetime smoking history, chronic airway disease (chronic bronchitis and/or asthma), occupational dust exposure, pneumonia as a child, single marital status and unemployment. Corticosteroid and bronchodilator therapy were also independent risk factors in the log-linear regression analysis, but may reflect the severity of underlying lung disease for which these drugs were prescribed. These data suggest that cigarette smoking is the major avoidable risk factor for acute pneumonia in adults.

Risk factors for community-acquired pneumonia diagnosed by general practitioners in the community

The purpose of this study was to identify risk factors for pneumonia diagnosed in the community by general practitioners, using a case control study in 29 general practices in Nottingham, U.K. Patients with radiographically confirmed pneumonia were compared with adults randomly selected from electoral registers corresponding to the catchment areas of the general practices taking part in the study. Sixty-six cases and 489 controls participated. Significant risk factors in univariate analysis included age, chronic obstructive pulmonary disease, congestive heart failure and lifetime consumption of cigarettes. Multiple logistic regression analysis of these four variables showed that age [adjusted odds ratio = 2.69 (for 30 year increment), 95%CI = 1.66-4.35] and chronic obstructive pulmonary disease (adjusted odds ratio= 1.99, 95%CI = 1.15-3.45) were independent risk factors. Only age and chronic obstructive pulmonary disease were independent risk factors for pneumonia in this study. Since cigarette smoking is the major cause of chronic obstructive pulmonary disease, these data suggest that cigarette smoking is the main avoidable risk factor for community-acquired pneumonia in adults.

Treatment of community-acquired pneumonia in the elderly: the role of cefepime, a fourth-generation cephalosporin

In a prospective, multicentre double-blind trial, 151 patients over the age of 65 years were randomly assigned to receive either cefepime 2 g every 12 h for a minimum of 3 days and up to 14 days or ceftriaxone 1 g every 12 h for a minimum of 3 days and up to 14 days. Antibiotics were maintained until 48 h after fever had resolved; no other antibiotics were permitted. The average age in each group exceeded 77 years and significant co-morbidity was found in the majority of patients. The mean total duration of therapy was 5.8+/-2.4 days for the cefepime group and 6.7+/-2.7 days for the ceftriaxone group (P = 0.06). The clinical success rate at the end of therapy was 79.1% with cefepime and 75.4% with ceftriaxone (P = 0.62). At the end of follow-up, 91.7% of the cefepime-treated patients and 86.5% of the ceftriaxone patients had a satisfactory clinical response (P = 0.38). In 35 bacteriological evaluable patients, potential pathogens were eradicated in all but one patient receiving cefepime. Seven patients in each group died during the study period but in each case the death was unrelated to study drug. The commonest side-effect was diarrhoea (cefepime, five patients; ceftriaxone, two patients). The clinical and microbiological efficacy of cefepime is similar to that of ceftriaxone in elderly patients with community-acquired pneumonia requiring hospitalization. Cefepime is an appropriate choice for the treatment of community-acquired respiratory tract infections in the elderly.

[Community-acquired pneumonia referred for hospital management. Its epidemiology and the diagnostic and therapeutic approaches]

OBJECTIVES

To determine the epidemiology of community-acquired pneumonia referred to the hospital and to characterize the diagnostic and therapeutic approach adopted by physicians.

METHOD

Retrospective epidemiological and descriptive clinical study based on case histories consistent with a diagnosis of community-acquired pneumonia (Fang et al. Medicine, 1990; 69:307-16) of patients referred to hospitals in Soria (Spain) over a period of one year. The patients were grouped by severity and the presence of risk factors for unusual etiology. Initial approaches were compared to those advocated by various sources.

RESULTS

Three hundred eight cases of community-acquired pneumonia were diagnosed, and 82% of the patients were admitted. Mean age was 68 +/- 26 years (43% over 80 years of age). Men accounted for 56%. Two hundred seventeen patients (70%) were classified as seriously ill, 203 (66%) had risk factors for unusual etiology, and 166 (54%) were classified in both categories. Mortality among admitted patients was 13%. Etiological diagnoses did not correspond to the guidelines of the Spanish Society of Pneumology and Chest Surgery (SEPAR), with microbial identification achieved in 5%. Empirical treatment followed SEPAR guidelines in 45% of the cases. The Mensa guidelines were followed in 23% and the Sanford guidelines in 20%.

CONCLUSIONS

The incidence of community-acquired pneumonia in this population is 3.2 cases per 1,000 inhabitants/year. The population is mainly elderly and comorbidity is common, although mortality is low. We believe common criteria should be adopted for managing community-acquired pneumonia and that empirical treatment should be directed toward germs identified in each setting, based on appropriate etiological investigation.

Community-acquired pneumonia guidelines--an international comparison: a view from Europe

Following an outline that details the pathogens causing community-acquired pneumonia (CAP) identified in studies from Europe, this article reviews the guidelines for the management of CAP in four European countries--France, Italy, Spain, and the United Kingdom. The method behind the development of each document is described, followed by a comparison of the scope of each document. All four documents provide guidelines for the management of two groups of patients--the severely ill and the nonseverely ill patient. A penicillin or macrolide feature for the nonseverely ill and the combination of a third-generation cephalosporin plus a macrolide for the severely ill patient are described in all four guidelines. Despite their different origins and methods, these four guidelines have more similarities than differences--the latter serving to emphasize some of the areas that require further research in this important condition. An important area for research is the impact that these guidelines have on practice and especially on clinical outcomes.

Microbial etiology of acute community-acquired pneumonia in adult hospitalized patients in Yaounde-Cameroon

OBJECTIVE: To determine the microbial etiology of acute community-acquired pneumonia in Yaoundé. METHODS: Ninety-one consecutive adult patients admitted to hospital for radiologically confirmed acute community-acquired pneumonia were studied prospectively. Sputum microscopy and culture, blood cultures, pneumococcal antigen detection in serum and serologic analysis for agents of atypical pneumonia and for human immunodeficiency virus (HIV) were performed for most patients. RESULTS: There were 65 men and 26 women, mean age 36.5 years. Of 91 patients, 70.3% had at least one predisposing factor and 21.7% (20 of 81) were seropositive for HIV. A microbial etiology was identified in 48 (52.7%) cases. A single pathogen was identified in 42 (85.4%) and double pathogens in six (14.6%). Bacteremia occurred in 12 of 81 patients and was significantly more common in HIV-seropositive than in HIV-seronegative patients. Streptococcus pneumoniae was the commonest causative agent, identified in 22 of 91 (24.2%) patients, 10 of whom were bacteremic. Atypical pathogens were diagnosed in 14 of 65 patients with serologic tests. Mycoplasma pneumoniae and Coxiella burnetii were diagnosed in six of 65 (9.2%) cases each, and Chlamydia pneumoniae in three (4.6%) patients. Mycoplasma pneumoniae and Chlamydia pneumoniae occurred as a dual infection in one case. Seven of 91 patients died, and death was not associated with any particular etiology. CONCLUSION: Streptococcus pneumoniae remains the predominant etiologic pathogen of community-acquired pneumonia. For this reason, and also because ampicillin used empirically to treat patients with this disease in the same setting has been shown to be efficacious, we propose the use of an aminopenicillin in the initial treatment of acute community-acquired pneumonia in adults in Yaoundé. However, patients who fail to respond clinically to such treatment should benefit from either a macrolide or a tetracycline in order to cover for atypical pathogens.

Severe community-acquired pneumonia in ICUs: prospective validation of a prognostic score

OBJECTIVE

To determine predictors of intensive care unit (ICU) mortality in patients with community-acquired pneumonia (CAP), to develop a pneumonia-specific prognostic index, and to evaluate this index prospectively.

DESIGN

Combined retrospective and prospective clinical study over two periods: January 1987-December 1992 and January 1993-December 1994.

SETTING

Four medical ICUs in the north of France.

PATIENTS

Derivation cohort: 335 patients admitted to one ICU were retrospectively studied to determine prognosis factors and to develop a pneumonia-specific prognostic index. Validation cohort: 125 consecutive patients, admitted to four ICUs, were prospectively enrolled to evaluate this index.

RESULTS

In the derivation cohort, 16 predictors of mortality were identified and assigned a value directly proportional to their magnitude in the mortality model: aspiration pneumonia (-0.37), grading of sepsis > or = 11 (-0.2), antimicrobial combination (-0.01), Glasgow score > 12+mechanical ventilation (MV) (+0.09), serum creatinine > or = 15 mg/l (+0.22), chest involvement shown by X-ray > or = 3 lobes (+0.28), shock (+0.29), bacteremia (+0.29), initial MV (+0.29), underlying ultimately or rapidly fatal illness (+0.31), Simplified Acute Physiology Score > or = 12 (+0.49), neutrophil count < or = 3500/ mm3 (+0.52), acute organ system failure score > or = 2 (+0.64), delayed MV (+0.67), immunosuppression (+1.38), and ineffective initial antimicrobial therapy (+1.5). An index was obtained by adding each patient's points. According to a receiver operating characteristic curve, the cut-off value of this index was 2.5. In the validation cohort, an index of > or = 2.5 could predict death with a positive predictive value of 0.92, sensitivity 0.61, and specificity 0.98.

CONCLUSION

This index, which performs well in classifying patients at high-risk of death, may help physicians in initial patient care (appropriateness of the initial antimicrobial therapy) and guide future clinical research (analysis and design of therapeutic trials).

Sputum gram's stain in community-acquired pneumococcal pneumonia. A meta-analysis

The usefulness of the sputum Gram's stain is controversial. This meta-analysis was designed to evaluate the sensitivity and specificity of the sputum Gram's stain in community-acquired pneumococcal pneumonia. Using a predetermined protocol, articles were discovered through a MEDLINE search (1966 to 1993) and the examination of bibliographies and were graded for quality by three blinded reviewers. Information on the reference standard, blinding, stain interpreter, control for antibiotic use, and definition of a positive test was collected. We found 12 articles containing 17 test characteristics to evaluate. The number of patients in each study ranged from 16 to 404. Sputum culture was the most common reference standard (10 of 17 estimations). Sensitivity ranged from 15% to 100% and specificity from 11% to 100%. Test characteristics varied markedly among studies and appeared related partly to the test interpreter. The sputum Gram's stain may yield misleading results in community-acquired pneumonia, as its sensitivity and specificity vary substantially in different settings. A practitioner electing to use the study should be well trained and use a specific definition for a positive test.

Appropriateness of hospitalization of patients with community-acquired pneumonia

STUDY OBJECTIVE

To investigate the association between the appropriateness of hospitalization and the course of hospitalization in patients with community-acquired pneumonia (CAP).

METHODS

We carried out a prospective study of 346 adult patients hospitalized with community-acquired pneumonia (CAP). Appropriateness of hospitalization was assessed with a modified appropriateness evaluation protocol (AEP) based on vital signs and laboratory tests. Hospitalizations that ended in death, lasted more than 4 days, or involved resuscitation, incubation, monitoring, or supplemental oxygen therapy were considered complicated.

RESULTS

According the AEP protocol, hospitalization was not appropriate for 210 of the 346 patients (61%). However, AEP proved to be an insensitive tool for the identification of patients with complicated hospital courses. Half of the 346 patients had complicated courses, including 82 of the 210 patients with inappropriate hospitalization (39%), according to the AEP. Four independent factors, age greater than 50 years, female sex, no antibiotic treatment before hospitalization, and more than 4 days of illness before admission predicted a complicated course in patients with inappropriate hospitalization as determined with the AEP criteria.

CONCLUSION

It is important to avoid the unnecessary hospitalization of patients with CAP. However, this should not be achieved at the expense of unjustified discharge from the emergency department. In the decision to hospitalize, additional prognostic factors, such as those presented here, should be taken into consideration to improve the admission process. This is particularly relevant for cases in which the AEP is invalid and indications for hospitalization are not clear cut. In these patients, a simpler and more precise scoring system should be developed.

Clinical utility of blood cultures in adult patients with community-acquired pneumonia without defined underlying risks

STUDY OBJECTIVE

We retrospectively examined the clinical utility of obtaining routine blood cultures before the administration of antibiotics in certain nonimmunosuppressed patients with community-acquired pneumonia (CAP) admitted to the hospital during 1991.

DESIGN

Retrospective review.

SETTING

Grady Memorial Hospital (a county hospital primarily serving inner-city Atlanta).

PATIENTS OR PARTICIPANTS

Hospital discharge diagnosis listings identified 1,250 adults ( > or = 18 years old) with pneumonia. From this group of patients, we selected patients admitted to the hospital with (1) respiratory symptoms and a lobar infiltrate on chest radiograph that were present at the time of hospital admission, (2) two or more sets of blood cultures obtained within 48 h of hospital admission, and (3) absence of defined risk factors: HIV-related illness, malignancy, recent chemotherapy, steroid therapy, sickle cell disease, nursing home residence, or hospital stays within the past 14 days.

MEASUREMENTS AND RESULTS

Five hundred seventeen patients (mean age, 52 years;: age range, 18 to 103 years) qualified. Of these 517 patients, 25 patients (4.8%) had growth in blood cultures considered contaminants while 34 (6.6%) had blood cultures positive for the following pathogens: 29 Streptococcus pneumoniae, 3 Haemophilus influenzae, and 1 Streptococcus pyogenes, 1 Escherichia coli. Antibiotic therapy was changed for 7 of the 34 patients with positive blood cultures (1.4% of study patients). Antibiotic regimens were altered in 48 additional patients based on sputum culture, poor clinical response, and allergic reactions.

CONCLUSIONS

Few blood cultures were positive for likely infecting organisms in adult patients with CAP without defined underlying risk factors. Furthermore, a total of $34,122 was spent on blood cultures at $66 per patient. In this carefully defined group of patients, blood cultures may have limited clinical utility and questionable cost-effectiveness.

A five-year study of severe community-acquired pneumonia with emphasis on prognosis in patients admitted to an intensive care unit

OBJECTIVES

To characterize the epidemiology and to determine the prognosis factors in severe community-acquired pneumonia among patients admitted to an intensive care unit.

DESIGN

Retrospective clinical study.

SETTING

Intensive Care and Infectious Diseases Unit of a municipal general hospital of Lille University Medical School.

PATIENTS

299 consecutive patients exhibiting severe community-acquired pneumonia.

MEASUREMENTS AND RESULTS

On admission to ICU, 149 patients required mechanical ventilation for acute respiratory failure and 44 exhibited septic shock. Pulmonary involvement was bilateral in 71 patients. There were 260 organisms isolated from 197 patients (65.9%), the most frequent being Streptococcus pneumoniae (n = 80), Staphylococcus spp. (n = 57) and Gram-negative bacilli (n = 81). Overall mortality was 28.5% (85 patients). According to univariate analysis, mortality was associated with age over 60 years, anticipated death within 5 years, immunosuppression, shock, mechanical ventilation, bilateral pulmonary involvement, bacteremia, neutrophil count < 3500/mm3, total serum protein level < 45 g/l, serum creatinine > 15 mg/l, non-aspiration pneumonia, ineffective initial therapy and complications. Multivariate analysis selected only 5 factors significantly associated with prognosis: anticipated death within 5 years, shock, bacteremia, non-pneumonia-related complications and ineffective initial therapy.

CONCLUSION

The effectiveness of the initial therapy appears to be the most significant prognosis factor and, as the one and only related to the initial medical intervention, suggests a need for permanent optimization of our antimicrobial strategies.

Overview of community-acquired pneumonia. Prognosis and clinical features

Despite the introduction of newer antibiotics, vaccinations, and better supportive care, CAP remains a common, frequently fatal disease. Age and coexisting illness influence which infectious agents are most likely to cause infection. Severity of illness and clinical features are influenced by various host factors and by the virulence of the infectious agent. Mortality and morbidity are reduced by the rapid institution of appropriate antimicrobial therapy. Because of the limitations of presently available diagnostic tests, many patients are begun on empiric regimens, and in up to half of these individuals, a cause is not identified. Although there are a number of potential pathogens, it is possible to identify likely pathogens based on easily identifiable clinical factors (age, presence of coexisting disease, severity of illness at presentation, and the need for hospitalization). Using this approach, CAP in immunocompetent adults may be divided into four categories. Once empiric therapy has been initiated, therapy should be continued for at least 72 hours unless clinical deterioration is noted. Within 4 days, fever and leukocytosis should return to baseline, but abnormal physical findings (i.e., crackles) require longer to resolve, especially with coexisting illness, and chest radiographic findings are the last to return to baseline and are especially delayed if the patient is bacteremic or has structural lung disease. Not all patients respond to initial empiric therapy. Reasons for this include antimicrobial resistance, the presence of nonbacterial pathogens (respiratory viruses), unusual bacterial pathogens, noninfectious causes that may mimic CAP, infectious complications (i.e., empyema), and pneumonia occurring in patients with unrecognized severe immunosuppression. Failure to improve after 72 hours and development of deterioration are indications for repeat diagnostic workup and consideration of alternative diagnoses. More invasive diagnostic tests are appropriate in severely ill patients and in those whose condition is deteriorating rapidly.

Severe community-acquired pneumonia. Etiology, epidemiology, and prognosis factors. French Study Group for Community-Acquired Pneumonia in the Intensive Care Unit

A prospective study of 132 patients with severe community-acquired pneumonia (CAP) treated in the ICU was carried out to determine the causative agents, the value of the clinical, biological, and radiologic features in predicting the etiology, and to define prognostic factors. The study group included 98 men and 34 women (mean age: 58 +/- 18 years). The most frequent underlying condition was COPD (51 patients, 39 percent). On admission, 35 patients were in shock, 71 were mentally confused, and 81 (61 percent) required mechanical ventilation during their hospitalization. The clinical, laboratory, and radiologic parameters were of little value for predicting the etiology in patients with severe CAP. An etiologic diagnosis was made in 95 (72 percent) patients. The most frequent pathogens were Streptococcus pneumoniae (43 cases [45 percent]), Gram-negative bacilli (14 cases [15 percent]), and Haemophilus influenzae (14 cases [15 percent]) Mortality was 24 percent. It was significantly associated with a age more than 60 years, septic shock, impairment of alertness, mechanical ventilation requirement, bacteremic pneumonia, and S pneumoniae or Enterobacteriaceae as the causes of the pneumonia. Recommendations for antibiotic chemotherapy in patients with severe CAP admitted to the ICU are included.

Quality of published reports of the prognosis of community-acquired pneumonia

OBJECTIVE

To systematically assess the quality of published reports of the prognosis of community-acquired pneumonia using a formal quality assessment instrument.

DESIGN

Retrospective review of studies published during 1966-1991. ARTICLES: 108 articles related to the prognosis of community-acquired pneumonia retrieved by a computerized search.

INTERVENTION

All articles, blinded to author(s), journal title, year of publication, and study institution(s), were independently reviewed by two investigators using a ten-item quality assessment instrument designed to evaluate: 1) identification of the inception cohort (4 items), 2) description of referral patterns (1 item), 3) subject follow-up (2 items), and 4) statistical methods (3 items). Adherence to each of the ten individual quality items and an overall quality score were calculated for all articles and across three time periods.

MAIN RESULTS

Among all 108 articles that underwent quality assessment, 30 were published from 1966 to 1979, 61 from 1980 through 1989, and 17 from 1990 through 1991. The mean total quality score of all articles was 0.55 (range 0.22-0.90). There was a significant trend toward improvement in total quality scores over the three time periods (0.50 to 0.56 to 0.65; p < 0.001). However, several systematic errors in the study design or reporting of these studies were discovered throughout time: only 3.7% provided comparative information about nonenrolled patients, 28.7% determined whether the study institution was a referral center, 36.1% specified inclusion or exclusion criteria, and 45.5% used appropriate statistical analyses to adjust for more than one prognostic factor.

CONCLUSIONS

Despite improvement in overall quality of published articles, systematic errors exist in the design and reporting of studies related to the prognosis of community-acquired pneumonia. The quality assessment tool employed in this study could be used to guide the development of high-quality outcomes research in the future.

Is pneumonia really the old man's friend? Two-year prognosis after community-acquired pneumonia

Is pneumonia "the old man's friend"--a terminal event for patients who will otherwise die soon of underlying chronic disease? If so, chronological age might influence treatment policy. We investigated the predictors of 2-year mortality after patients' admission to hospital for community-acquired pneumonia, and focused on the predictive value of age. In a prospective cohort study 141 consecutive patients were admitted to hospital with community-acquired pneumonia. Clinical, laboratory, and sociodemographic data were collected on admission. Comorbidity was categorised as mild, moderate, or severe by a physician based on the patient's medical history. Survival was assessed at 24 months after discharge. 22 (16%) patients died in hospital. Of the remaining 119, 38 (32%) died over the next 24 months. In a Cox model, 2-year mortality was independently related to severe comorbidity (relative risk [RR] = 9.4) or moderate comorbidity (RR = 3.1), and to haematocrit less than 35% (RR = 2.9) (all p < or = to 0.005). However, compared with patients aged 18-44 years, patients aged 45-64 (RR = 0.84), 65-74 (RR = 1.28), and 75-92 (RR = 1.99) were not significantly more likely to die during the 24 months after discharge (all p > or = to 0.2). Old age should not be a sole criterion for withholding aggressive treatment of community-acquired pneumonia.

A prospective study of community-acquired pneumonia in Hong Kong

A prospective study of community-acquired pneumonia in Hong Kong was carried out between January and December, 1988. Ninety adults (57 male) with a mean age of 57.3 years were admitted to the Prince of Wales Hospital with community-acquired pneumonia. The etiologic diagnosis of pneumonia was made in 37 cases (41 percent). Pneumococcal infection was diagnosed in 11 patients (12 percent). The same number of patients had pulmonary tuberculosis presenting as acute pneumonia. It could not be differentiated from other causes of pneumonia on clinical and radiologic grounds, although pleural effusion and upper lobe involvement were more common in patients with tuberculosis. Chlamydia species were identified in five patients (6 percent) and Mycoplasma pneumoniae was identified in three patients (3 percent). There was no case of Legionnaires' disease. The etiologic agent could not be identified in 59 percent of cases. The low incidence of etiologic diagnosis of community-acquired pneumonia was probably related to the widespread use of antibiotics in private practice. Tuberculosis is an important cause of community-acquired pneumonia in Hong Kong and this diagnosis should be considered in patients who fail to respond to first-line antibiotics.

The value of routine microbial investigation in community-acquired pneumonia

The way in which microbiological investigations are used in routine clinical practice and the value of such tests in directing antibiotic prescribing, was studied in adults admitted to hospital with a diagnosis of community-acquired pneumonia. One-hundred and twenty-two consecutive patients admitted to one teaching and one district general hospital were studied between April 1988 and March 1989. Blood cultures were performed in 81% of cases, sputum was examined in 45% and complete serological tests were performed in 28%. No causative pathogen was found in 74% of cases and results of microbial tests directed a change in antibiotic therapy in only 8% of cases. Routine microbial investigation of all adults admitted to hospital with community-acquired pneumonia is unhelpful and probably unnecessary. We suggest a strategy for microbial investigation linked to initial illness severity to replace the current haphazard approach.

Prospective hospital study of community acquired lower respiratory tract infection in the elderly

A prospective study of community acquired lower respiratory tract infection in the elderly was carried out over a 15-month period. During this time 127 consecutive admissions to two acute geriatric medical wards were studied. An aetiology was established in 77 (61%) of cases. Streptococcus pneumoniae was identified in 37% of patients. Haemophilus influenzae in 18% and Branhamella catarrhalis in 10%. Infection with Mycoplasma pneumoniae was found in only one episode and no cases of Legionella pneumophilia were diagnosed. A significant number of patients had multiple bacterial pathogens isolated: 18% of all bacterial pathogens isolated were ampicillin resistant. Fourteen patients died (11%). Lower respiratory tract infection is a frequent cause of hospital admission for those aged over 65 and is often regarded as a preterminal event. Adequately treated however, mortality is no higher than in the general population. Knowledge of the likely pathogens allows early and appropriate antibiotic therapy for these patients whether at home or on admission to hospital.

Variation in time and space of non-outbreak Legionnaires' disease in Scotland

The main aim of this study was to measure and explain geographic variations in the incidence of Legionnaires' disease in Scotland, particularly to help understand the source of non-outbreak infection. Between 1978 and 1986 the overall mean annual incidence rate was 7.9 per million (range 3.1-20.2), and for non-outbreak, non-travel cases it was 5.6. There were geographical variations by health board, by city and within cities, e.g. the mean annual incidence rate per million for non-travel, non-outbreak disease was 1.2 in Tayside Health Board, 3.7 in Lanarkshire, 5.6 in Lothian and 14.4 in Greater Glasgow. In Greater Glasgow Health Board non-travel cases lived in and around the city centre and in some postcode sectors there, the mean annual incidence rate exceeded 100. Travel-related cases lived in peripheral areas. These variations could not be explained by differences in access to and use of diagnostic services, surveillance, or host susceptibility (as reflected by socioeconomic status and frequency of other respiratory disease). The explanation probably lay in environmental factors, though differences in agent virulence were not excluded. The two main conclusions are, that non-outbreak cases were not truly sporadic, and that the space-time variations in incidence support the hypothesis that cooling towers were an important source of infection for non-travel, non-outbreak cases. If so such infection is potentially preventable.

Hospitalization decision in patients with community-acquired pneumonia: a prospective cohort study

PURPOSE

To identify a low-risk subset of patients with community-acquired pneumonia that could safely be treated in the ambulatory setting; and to assess how clinicians make the hospitalization decision.

PATIENTS AND METHODS

We performed a prospective, observational study of 280 ambulatory and hospitalized adults with clinical and radiographic evidence of pneumonia. Patients were followed to assess all potential morbid complications and 6-week mortality. Physicians responsible for managing these patients were surveyed to assess the reasons for treating in a hospital or ambulatory setting and the therapies that dictate hospitalization.

RESULTS

Sixty-one percent (170 of 280) of patients did not have an indication for admission at presentation using modified Appropriateness Evaluation Protocol criteria (a severe vital sign abnormality, alteration in mental status, suppurative complication, arterial hypoxemia, severe laboratory abnormality, or an acute coexistent medical problem requiring admission independent of the pneumonia). Among these 170 patients, 38% had a complicated course defined as death within 6 weeks, development of a new suppurative or medical complication due to pneumonia, intensive care unit admission, persistent fever or use of intravenous fluids or oxygen beyond 3 days, hospitalization lasting more than 3 days, or subsequent hospitalization in patients initially treated in the ambulatory setting. Five predisposing factors for a complicated course were identified in logistic regression models. The odds ratio for age more than 65 years was 2.7; for comorbid illness, 3.2; for temperature more than 38.3 degrees C (101 degrees F), 4.1; for immunosuppression, 12.0; and for a high-risk etiology, 23.3. The risk of a complicated course increased linearly with the number of risk factors, from 12% with none to 100% with four or more factors (p less than 0.001). Physicians most often relied on the general clinical appearance of the patient when making the triage decision, and most commonly cited intravenous antibiotics and chest physical therapy as treatments requiring hospitalization.

CONCLUSIONS

If validated, our findings could improve physicians' assessment of prognosis, and may identify a low-risk subset of patients with community-acquired pneumonia who could safely be managed in the ambulatory setting.

Rapid aetiological diagnosis of pneumonia based on routine laboratory features

The values of some basic laboratory features on admission to hospital were recorded and compared in 418 adult patients with community-acquired pneumonia, namely erythrocyte sedimentation rate, C-reactive protein, white blood cell (WBC) count, serum lactate dehydrogenase (S-LD), serum alanine-aminotransferase, and serum sodium. Discriminant analysis was performed to obtain an aetiological diagnosis. WBC value of greater than 15 x 10(9)/l strongly indicated a bacterial and, especially a pneumococcal aetiology, whereas increased S-LD could imply a mycoplasmal infection. For patients less than 50 years of age the equation C2 = -1.788 + 0.204 x WBC-0.0909 X S-LD was constructed, in which C2 greater than 0 indicated a pneumococcal aetiology. This function correctly classified 31/33 (93.9%) patients with a mycoplasmal and 20/31 (64.5%) patients with a pneumococcal infection. Patients with viral, Haemophilus influenzae or chlamydial infection could not be discriminated from each other. The age of the patient, WBC and possibly S-LD on admission are easily accessible parameters and these results could therefore be of value in daily clinical practice in hospitals.

Legionella: an infrequent cause of adult community acquired pneumonia in Dublin

The commonest infectious agents identified in community acquired pneumonia (CAP) amongst 50 patients admitted to a Dublin hospital were Streptococcus pneumoniae and Haemophilis influenzae. Legionella pneumophila pneumonia occurred in only one patient who acquired infection abroad. A serological screen of blood bank donors and renal transplant recipients failed to detect antibody to Legionella pneumophila supporting the clinical findings of a low prevalence of infection in this community. It is concluded that initial antibiotic therapy for patients with CAP need not routinely include cover for Legionella.

Pneumonias in adults due to mycoplasma, chlamydiae, and viruses

Pneumonias in adults due to mycoplasma, chlamydiae, and viruses are a common clinical problem. These microorganisms contribute to the etiologies in 6-35% of all cases of pneumonia and are the sole pathogens in 1-17% of hospitalized cases. Important trends and developments in the field include the emergence of a Chlamydia psittaci strain (TWAR) that is passaged from human to human, causes a mycoplasma-like illness, and that is relatively resistant to erythromycin, the recognition of respiratory syncytial virus as a pathogen in nursing home outbreaks and in immunosuppressed adults, the continuing high lethality of fully developed influenza pneumonia, the efficacy of acyclovir and adenine arabinoside in limiting the complications of varicella-zoster virus infections, and the increasing frequency of pneumonia caused by cytomegalovirus and the severity of this disorder in highly immunosuppressed patients. Developments in the rapid diagnosis and therapy of respiratory syncytial virus infections with an aerosolized antiviral drug in children may pave the way for comparable advances in difficult pneumonias in adult patients.

Comparative clinical and laboratory features of legionella with pneumococcal and mycoplasma pneumonias

The clinical and laboratory features of 83 cases of community-acquired pneumococcal pneumonia (PP), 79 cases of legionella pneumonia (LP) and 62 cases of mycoplasma pneumonia (MP) have been compared. No unique features have been found in any group. Patients with MP were younger, were more likely to have had prior antibiotics before hospital referral, had a predominance of upper respiratory tract symptoms, low total white cell counts and lacked features of multisystem involvement. Multisystem features were common in both PP and LP with confusion, high fever, hyponatraemia, hypoalbuminaemia and abnormalities of liver function occurring more often in LP. A high leucocyte count was especially common in PP. Antibiotic therapy in community-acquired pneumonia must remain empirical until a definite microbiological diagnosis is made.

Prospective study of the aetiology and outcome of pneumonia in the community

A prospective one-year study of community pneumonia was conducted in Nottingham. 236 of 251 episodes of pneumonia (defined as an acute lower respiratory tract infection, for which antibiotics were prescribed, associated with new focal signs on examination of the chest) were investigated. Acute radiographic changes were present in 93 (39%). A pathogen was identified in 129 (55%) episodes, with Streptococcus pneumoniae, Haemophilus influenzae, and influenza viruses those most frequently identified. Mycoplasma pneumoniae was uncommon and infection with Legionella pneumophila was found in only 1 episode. Hospital admission was required in 52 (22%) episodes. 7 patients died (3%), all but one of the deaths occurring in patients who had been admitted to hospital. Pneumonia in the community is common but few people die of it. Initial antibiotic therapy should always cover S pneumoniae and H influenzae.

Aetiology of community-acquired pneumonia in hospital treated patients

From May 1982 a prospective 1-year study of adult patients with community-acquired, radiologically verified, hospital treated pneumonia was performed at the Department of Infectious Diseases, Orebro Medical Center Hospital, Orebro, Sweden. The study included 147 patients with a median age of 71 years. Special efforts to diagnose a pneumococcal aetiology were accomplished by antigen detection of the pneumococcal C-polysaccharide (PnC) in sputum and saliva samples and by serological methods for determination of antibody titres against PnC. A pneumococcal aetiology was established in 46.9% of the patients, including 8.1% with double infections. Altogether Haemophilus influenzae A virus were noted in 9.5%, respectively, Mycoplasma pneumoniae in 5.4%, legionnaires' disease in 2.7% and Branhamella catarrhalis in 2.0%, whereas enteric gram-negative bacilli as aetiological organisms were not found in any patient. These findings imply that penicillin should still be the first drug of choice in hospitalized adult patients with community-acquired pneumonia in Sweden.