Community acquired pneumonia: aetiology and prognostic index evaluation

Species distribution and susceptibility of Nocardia isolates in New Zealand 2002-2021

The aim was to record the distribution and susceptibility of Nocardia species in New Zealand. Local and referred isolates were identified by an evolving approach over the study period including conventional phenotypic methods, susceptibility profiles, matrix-assisted laser desorption ionisation-time of flight mass spectrometry (MALDI-TOF) and molecular sequencing. Isolates previously identified as a Nocardia sp. or part of the N. asteroides complex were reidentified by MALDI-TOF and/or molecular methods. Antimicrobial susceptibility to eight antibiotics was performed by standard microbroth dilution. The site of isolation, susceptibility profiles and species distribution were analysed. A total of 383 isolates were tested: N. brasiliensis 23 (6%), N. cyriacigeorgica 42 (11%), N. farcinica 41 (11%), N. nova complex 226 (59%), and 51 (13%) other species/complexes. The respiratory tract was the most common site of infection (244, 64%), with skin and soft tissue the second most common site (104, 27%). All 23 N. brasiliensis isolates were from skin and soft tissue specimens. Almost all isolates (≥98%) were susceptible to amikacin, linezolid and trimethoprim-sulfamethoxazole; 35% and 77% were resistant to clarithromycin and quinolones, respectively. The expected susceptibility profiles of the four common species and complex were observed for most agent-organism parings. Multi-drug resistance was uncommon (3.4%). The spectrum of Nocardia species in New Zealand is similar to overseas reports and our most common group is the N. nova complex. While amikacin, linezolid and trimethoprim-sulfamethoxazole remain good empiric treatment choices, other agents should have their activity confirmed before use.

Q Fever as a Cause of Community-Acquired Pneumonia in French Guiana

In French Guiana, community-acquired pneumonia (CAP) represents over 90% of Coxiella burnetii acute infections. Between 2004 and 2007, we reported that C. burnetii was responsible for 24.4% of the 131 CAP hospitalized in Cayenne. The main objective of the present study was to determine whether the prevalence of Q fever pneumonia remained at such high levels. The secondary objectives were to identify new clinical characteristics and risk factors for C. burnetii pneumonia. A retrospective case-control study was conducted on patients admitted in Cayenne Hospital, between 2009 and 2012. All patients with CAP were included. The diagnosis of acute Q fever relied on titers of phase II IgG ≥ 200 and/or IgM ≥ 50 or seroconversion between two serum samples. Patients with Q fever were compared with patients with non-C. burnetii CAP in bivariate and multivariate analyses. During the 5-year study, 275 patients with CAP were included. The etiology of CAP was identified in 54% of the patients. C. burnetii represented 38.5% (106/275; 95% CI: 31.2-45.9%). In multivariate analysis, living in Cayenne area, being aged 30-60 years, C-reactive protein (CRP) > 185 mg/L, and leukocyte count < 10 G/L were independently associated with Q fever. The prevalence of Q fever among CAP increased to 38.5%. This is the highest prevalence ever reported in the world. This high prevalence justifies the systematic use of doxycycline in addition to antipneumococcal antibiotic regimens.

The mysterious illness that drove them to their knees - Ah, that Legionnaires' disease - A historical reflection of the work in Legionnaires' disease in New Zealand (1978 to mid-1990s) and the 'One Health' paradigm

And so, formed the basis for the song Legionnaires' disease (LD) composed by the legendry musician Bob Dylan shortly after this mysterious illness dramatically entered the clinical and epidemiological scene in July 1976 at an American hotel. Now more than forty years have passed since Legionella pneumophila, the causative agent of LD, was formally identified in 1977. Once the publicity associated with the outbreak subsided, there was the challenge to science and health professionals of what was an extremely complex and intriguing health concern. In the United States, the outbreak investigation that eventually solved the mystery had taken an array of surprising twists and turns. Globally, it revealed the strengths and weakness of countries' health systems in response to the outbreak from an unknown agent. Extensive international coverage of the outbreak also marked a turning point in journalism's efforts to hold officials accountable for their response to epidemics that had the potential to threaten the lives of hundreds of people. In 1979, New Zealand became an active participant in the international efforts towards increasing the understanding of infection caused by Legionella species and set up a centralized laboratory diagnostic service. By 1980 LD had become a notifiable disease making New Zealand one of the first countries globally to do so. This historical narrative in the decade or so from its recognition, provides a unique insight into how the One Health paradigm was instrumental in New Zealand's early response to LD in tandem with control strategies. The findings show that from 1979 the distribution of the Legionella species in New Zealand did not follow patterns observed in studies carried out globally.

Prognostic implications of aspiration pneumonia in patients with community acquired pneumonia: A systematic review with meta-analysis

Aspiration pneumonia is thought to be associated with a poor outcome in patients with community acquired pneumonia (CAP). However, there has been no systematic review regarding the impact of aspiration pneumonia on the outcomes in patients with CAP. This review was conducted using the MOOSE guidelines: Patients: patients defined CAP. Exposure: aspiration pneumonia defined as pneumonia in patients who have aspiration risk. Comparison: confirmed pneumonia in patients who were not considered to be at high risk for oral aspiration. Outcomes: mortality, hospital readmission or recurrent pneumonia. Three investigators independently identified published cohort studies from PubMed, CENTRAL database, and EMBASE. Nineteen studies were included for this systematic review. Aspiration pneumonia increased in-hospital mortality (relative risk, 3.62; 95% CI, 2.65–4.96; P < 0.001, seven studies) and 30-day mortality (3.57; 2.18–5.86; P < 0.001, five studies). In contrast, aspiration pneumonia was associated with decreased ICU mortality (relative risk, 0.40; 95% CI, 0.26–0.60; P < 0.00001, four studies). Although there are insufficient data to perform a meta-analysis on long-term mortality, recurrent pneumonia, and hospital readmission, the few reported studies suggest that aspiration pneumonia is also associated with these poor outcomes. In conclusion, aspiration pneumonia was associated with both higher in-hospital and 30-day mortality in patients with CAP outside ICU settings.

Community-acquired pneumonia caused by carbapenem-resistant Streptococcus pneumoniae: re-examining its prevention and treatment

A 73-year-old man with no significant past medical history or any history of health care visits was hospitalized for pneumonia. Sputum culture revealed multidrug-resistant Streptococcus pneumoniae, even to carbapenems. The patient was later treated successfully with levofloxacin. Throat cultures from his two grandchildren revealed S. pneumoniae with the same susceptibility pattern. Analysis for resistant genes revealed gPRSP (pbp1a + pbp2x + pbp2b gene variants) in both the patient and his grandchildren, none of whom had received pneumococcal vaccines of any kind. This case illustrates the importance of the emergence of carbapenem-resistant S. pneumoniae. Non-rational use of carbapenems for community-acquired infections may be counterproductive. This case also highlights the importance of pneumococcal vaccinations in children and the elderly.

Bacterial Infections

In Osier’s time, bacterial pneumonia was a dreaded event, so important that he borrowed John Bunyan’s characterization of tuberculosis and anointed the pneumococcus, as the prime pathogen, “Captain of the men of death.”1 One hundred years later much has changed, but much remains the same. Pneumonia is now the sixth most common cause of death and the most common lethal infection in the United States. Hospital-acquired pneumonia is now the second most common nosocomial infection.2 It was documented as a complication in 0.6% of patients in a national surveillance study,3 and has been reported in as many as 20% of patients in critical care units.4 Furthermore, it is the leading cause of death among nosocomial infections.5 Leu and colleagues6 were able to associate one third of the mortality in patients with nosocomial pneumonia to the infection itself. The increase in hospital stay, which averaged 7 days, was statistically significant. It has been estimated that nosocomial pneumonia produces costs in excess of $500 million each year in the United States, largely related to the increased length of hospital stay.

Community-acquired Acinetobacter infections

Acinetobacter infections have been attracting increasing attention during recent years because they have become common in hospitalized patients, especially in the intensive care unit (ICU) setting. However, the available literature suggests that the pathogen has another fearful potential; it can cause community-acquired infections. We searched PubMed and the reference lists of the initially identified articles and identified six case series regarding a total of 80 patients with community-acquired Acinetobacter baumannii infections; from these, 51 had pneumonia and 29 had bacteremia. Of these 80 patients, 45 (56%) died of the infection. In addition, we identified 26 case reports regarding 43 patients with community-acquired Acinetobacter infections; from these, 38 had pneumonia, two had meningitis, one had soft-tissue infection, one had ocular infection, and one had native valve endocarditis. Comorbidity was commonly present in patients reported in the case series as well as the case reports, mainly, chronic obstructive pulmonary disease, renal disease, and diabetes mellitus; heavy smoking and excess alcohol consumption were also common. Most of the studies originated from China, Taiwan, and tropical Australia. We also identified 12 retrospective or prospective studies (seven from the Far East, two from Oceania, one from N. Guinea, one from Palestine, and one from USA/Canada) that reported the frequency of community-acquired Acinetobacter infections; the range of isolation of Acinetobacter from patients with community-acquired pneumonia in these studies was 1.3%-25.9%. In conclusion, most community-acquired Acinetobacter infections have been reported from countries with tropical or subtropical climate, and mainly affect patients with some form of comorbidity or are associated with heavy smoking and excess alcohol consumption.

Community-Acquired Respiratory Complications in the Intensive Care Unit: Pneumonia and Acute Exacerbations of COPD

This chapter will review the two most common lower respiratory tract infections in the intensive care unit (ICU), community-acquired pneumonia (CAP) and acute exacerbations of chronic obstructive pulmonary disease (AECOPD). In addition we will provide an overview of the topics including recommendations for the diagnosis and treatment.

[Follow-up criteria for community acquired pneumonias and acute exacerbations of chronic obstructive pulmonary disease]

The follow-up of Community Acquired Pneumonias (CAP) and Acute Exacerbations of Chronic Obstructive Pulmonary Diseases (AECOPD) differs with the setting of care, but overall calls upon the same investigations as the initial evaluations. In the event of initial ambulatory care, the evaluation is carried out primarily on clinical data, at the 2 or 3rd day for the CAP, at the 2nd to 5th day for the AECOPD. In the event of unfavourable evolution, or from the start in the most severe cases, the follow-up is carried out in hospital; clinical evaluation is readily daily, and all the more frequent that the clinical condition is worrying because of the severity or risk factors. The investigations will be limited to those initially abnormal in the event of favourable evolution; on the contrary, unfavourable evolution can justify new investigations which depend on clinical characteristics. Remotely, i.e. 4 to 8 weeks later, must be checked the return at the baseline clinical state, a chest X-ray (CAP), spirometry and arterial blood gas (AECOPD), even bronchoscopy and thoracic CT-scan.

The role of new therapies for severe community-acquired pneumonia

PURPOSE OF REVIEW

Community-acquired pneumonia (CAP) is associated with significant morbidity and mortality and is the most common cause of death from infectious diseases. CAP patients requiring intensive care unit (ICU) admission carry the highest mortality rates. This paper aims to review the current literature regarding epidemiology, risk factors, severity criteria and reasons for admitting the hospitalized patient to the ICU, and the empiric and specific antibiotic therapeutic regimens employed.

RECENT FINDINGS

Multiple sets of clinical practice guidelines have been published in the past few years addressing the treatment of CAP. The guidelines all agree that CAP patients admitted to the hospital represent a major concern, and appropriate empiric therapy should be instituted to improve clinical outcomes.

SUMMARY

The cost, morbidity and mortality of CAP patients requiring ICU admission remain unacceptably high. These are heterogeneous groups of patients, so it is important to use risk-stratification based on clinical parameters and prediction tools. Appropriate antibiotic therapy is an important component in the management of both groups of patients. In particular, it is essential to administer an appropriate antimicrobial agent from the initiation of therapy, so that the risks of treatment failure and the morbidity of CAP may be minimized.

Enhancing the etiologic diagnosis of community-acquired pneumonia in adults using the urinary antigen assay (Binax NOW)

OBJECTIVES

Approximately 40% of community-acquired pneumonia (CAP) remains of unknown etiology. To improve the rate of detection of the causative microbiologic agent, the Binax NOW Streptococcus pneumoniae urinary antigen test (UAT) was evaluated.

DESIGN

In this prospective study, 67 adults with CAP were compared with 81 healthy patients to determine sensitivity and specificity of the UAT and its role in improving the etiologic diagnosis of CAP.

RESULTS

An etiology could be found for 22 patients (33%) using conventional methods (14 S. pneumoniae, sensitivity 64.3%, 1/81 positive UAT control urine samples, specificity 98.8%). This proportion increased to 33 patients (49%) with the addition of the urinary antigen test (p = 0.039). Pneumococcal infection was diagnosed by the UAT in 24% of our patients without an etiologic identification by conventional methods.

CONCLUSIONS

Given its excellent specificity, this test can be considered an important tool for detecting S. pneumoniae in CAP of unknown etiology, enabling the diagnosis of pneumococcal pneumonia in a quarter of cases.

Validation of predictive rules and indices of severity for community acquired pneumonia

BACKGROUND

A study was undertaken to validate the modified American Thoracic Society (ATS) rule and two British Thoracic Society (BTS) rules for the prediction of ICU admission and mortality of community acquired pneumonia and to provide a validation of these predictions on the basis of the pneumonia severity index (PSI).

METHOD

Six hundred and ninety six consecutive patients (457 men (66%), mean (SD) age 67.8 (17.1) years, range 18-101) admitted to a tertiary care hospital were studied prospectively. Of these, 116 (16.7%) were admitted to the ICU.

RESULTS

The modified ATS rule achieved a sensitivity of 69% (95% CI 50.7 to 77.2), specificity of 97% (95% CI 96.4 to 98.9), positive predictive value of 87% (95% CI 78.3 to 93.1), and negative predictive value of 94% (95% CI 91.8 to 95.8) in predicting admission to the ICU. The corresponding predictive indices for mortality were 94% (95% CI 82.5 to 98.7), 93% (95% CI 90.6 to 94.7), 49% (95% CI 38.2 to 59.7), and 99.5% (95% CI 98.5 to 99.9), respectively. These figures compared favourably with both the BTS rules. The BTS-CURB criteria achieved predictions of pneumonia severity and mortality comparable to the PSI.

CONCLUSIONS

This study confirms the power of the modified ATS rule to predict severe pneumonia in individual patients. It may be incorporated into current guidelines for the assessment of pneumonia severity. The CURB criteria may be used as an alternative tool to PSI for the detection of low risk patients.

Medium-Term Survival after Hospitalization with Community-Acquired Pneumonia

An episode of community-acquired pneumonia (CAP) has been suggested to predict greater than expected mortality after discharge from hospital. We ascertained the survival status as of December 2002 of a cohort of patients with CAP identified prospectively between November 1998 and June 2001. Cox regression analysis was used to examine the impact of demographic factors, comorbid illnesses, and CAP severity on subsequent mortality. Of 378 CAP survivors we ascertained the survival status of 366 (96.9%), 125 (34.1%) of whom had died. The mean length of follow-up was 1,058 days (range, 602-1,500 days). Independent predictors of mortality were increasing age (p < 0.001), comorbid cerebrovascular (p = 0.002) and cardiovascular (p = 0.023) disease, an altered mental state (p < 0.001), a hematocrit of less than 35% (p = 0.035), and increasing blood glucose level (p = 0.025). In 41- to 80-year-olds without significant comorbidities there was a trend to greater than expected mortality. In conclusion, an episode of CAP in young adults without significant comorbid illnesses does not appear to be an adverse prognostic marker of medium-term survival. The trend to greater than expected mortality in patients over 40 years of age needs further study and physicians should be particularly alert for underlying life-limiting disease processes in patients presenting with acute confusion or a hematocrit of less than 35%.

Community-acquired pneumonia: influence of management practices on length of hospital stay

AIMS

To identify variation in the management of -community-acquired pneumonia between two New Zealand hospitals and the factors that may account for any differences.

METHODS

A 12-month, prospective two-centre study was conducted. Between July 1999 and July 2000, 474 adult patients with community-acquired pneumonia were enrolled: 304 in Christchurch Hospital and 170 in Waikato Hospital. The patients were similar in age, sex, prior antibiotic use and comorbidity. There was no significant difference in the clinical outcomes for the patients at the two centres.

RESULTS

The mean duration of i.v. antibiotic therapy was 1.7 versus 3.0 days (P < 0.001) and length of stay (LOS) was 3.0 versus 5.9 days (P < 0.001) for Waikato and Christchurch Hospitals, respectively. Using multivariate analysis, we could account for 61% of the observed variation in LOS. Duration of i.v. antibiotic therapy independently accounted for 16% of variation in LOS compared with age (2%), chronic obstructive pulmonary disease, duration of fever, intensive care unit admission and centre of admission (all <1%). For the duration of i.v. antibiotics, centre of admission, largely reflecting clinician practice at each centre, independently accounted for 13% of variation, compared with duration of fever (5%), admission to the Intensive Care Unit (4%), Pneumonia Severity Index score (3%) and bacteraemia (3%).

CONCLUSION

Of the identifiable factors, variations in clinician behaviour outweighed the influence of patient factors on the duration of i.v. antibiotic therapy, which in turn was the major determinant of LOS for patients hospitalised with community-acquired pneumonia. An early switch from i.v. to oral antibiotic therapy in conjunction with early discharge planning may significantly reduce LOS without compromising patient outcomes.

Guidelines for community-acquired pneumonia in the ICU

Community-acquired pneumonia remains a common and serious condition worldwide. Severe community-acquired pneumonia requiring ICU admission is a distinct entity with different pathogens, outcomes, and management. The mortality rate in severe community-acquired pneumonia can be more than 50%. Over the past decade, some international guidelines for the management of community-acquired pneumonia have been developed in an attempt to optimize patient care. These guidelines have developed prediction tools to direct clinicians in the management of community-acquired pneumonia, including when to admit a patient to the ICU and selecting appropriate investigations and antimicrobial therapy. The individual recommendations of these guidelines and the guidelines as a whole require further studies.

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.

Applying sputum as a diagnostic tool in pneumonia: limited yield, minimal impact on treatment decisions

STUDY OBJECTIVES

We evaluated the role of sputum examination in the management of patients with community-acquired pneumonia (CAP) in a primary-care hospital without microbiologic laboratory facilities.

DESIGN AND INTERVENTIONS

A diagnostic strategy using regular collection of sputum samples, Gram staining in a local laboratory, and mailing of samples to a commercial laboratory for culture analysis.

SETTING

A 200-bed primary-care hospital without subspeciality physicians.

PATIENTS

One hundred sixteen consecutive patients with a diagnosis of CAP were prospectively evaluated during a 12-month period.

RESULTS

Of 116 patients, 42 patients (36%) were capable of producing a sputum sample. Age > or = 75 years (odds ratio [OR], 0.4; 95% confidence interval [CI], 0.18 to 0.93) and prior ambulatory antimicrobial treatment (OR, 3.2; 95% CI, 1.2 to 8.4) were independent predictors of sputum production. A delay in collection and processing of sputum samples of > 24 h was present in 31% and 39%, respectively. A delay in collection yielded an increased number of Gram-negative enteric bacilli and nonfermenters (44% vs. 7%, p = 0.056). A delay in processing was associated with an increased number of Candida spp isolates (33% vs. 9%, p = 0.16). The overall diagnostic yield was low (10 of 116 patients, 9%) due to a limited number of valid samples (n = 23 of 42 patients, 55%) and a limited number of definitely or probably positive samples on Gram's stain and culture (n = 10 of 42 patients, 24%). Prior ambulatory antimicrobial treatment was associated with a reduction in diagnostic yield (14% vs. 56%, p = 0.09). The impact of diagnostic results on antimicrobial treatment decisions was minimal, with antimicrobial treatment directed to diagnostic results in only one patient.

CONCLUSIONS

We conclude that in this setting representative of primary-care hospitals in Germany, sputum had a low diagnostic yield and did not contribute significantly to patient management.

Community-acquired pneumonia--implementation of a prediction rule to guide selection of patients for outpatient treatment

The aim of this study was to determine the outcomes of outpatient treatment of community-acquired pneumonia (CAP) when a prediction rule was followed by emergency physicians to guide the selection of patients. This was a prospective observational study conducted at the emergency department of a university-affiliated hospital in Hong Kong, China. A clinical prediction rule was implemented to guide the selection of patients with CAP for outpatient treatment. All subsequent hospitalizations gial presentation were recorded, and the reasons were assessed. The utilization of the observation unit was incorporated into the treatment algorithm. Of 72 patients with CAP followed up as outpatients, 60 (83.3%) were treated successfully, nine (12.5%) required subsequent hospitalization within 30 days, and three (4.2%) were lost to follow-up. None of the patients died, and none required admission to the intensive care unit. Factors associated with subsequent hospitalization include: tuberculosis, underlying malignancy, persistent fever, comorbidity (rheumatoid arthritis and severe osteoporosis), intravenous drug addiction and alcoholism. The observation ward was utilized in 10 (16.7%) patients successfully treated as outpatients. It is concluded that the prediction rule can be safely implemented as a guide for emergency physicians. The short-stay observation unit may be usefully employed for treating low-risk CAP.

Defining severe community-acquired pneumonia

Based on the recognition of the main pathophysiologic features of pneumonia and currently available data on prognosis and clinical severity assessment, key points for a definition of severe pneumonia are as follows: 1. Independent predictors of pneumonia severity are factors reflecting acute respiratory failure and severe sepsis or septic shock. 2. In view of the dependence of the development of acute respiratory failure on pulmonary comorbidities, radiographic extension may prove to be an additional independent predictor of severe respiratory compromise. 3. Vital sign abnormalities other than acute respiratory failure and severe hypotension may be independent predictors of severity, particularly in patients presenting in early and asymptomatic stages of severe sepsis. 4. Several pathogens have been shown to have adverse prognostic potential. Because the cause is unknown at the initial evaluation, however, pathogens cannot form part of the criteria for the initial severity assessment. 5. Because pneumonia is a dynamic process, any assessment of severity takes place at an arbitrary point of disease evolution. It would be desirable to define a set of parameters reflecting initial severity as well as a state of increased risk for early deterioration toward severe pneumonia. 6. Severity stratification within the population of patients with severe pneumonia may open the prospect of identifying patients who may have the greatest benefit from intensive care.

Community-acquired pneumonia. Diagnostic and therapeutic approach

Optimal empiric therapy of CAP is with appropriate monotherapy (e.g., doxycycline, levofloxacin). Combination therapy is problematic because of potential side effects and high cost. Empiric coverage should have a high degree of activity against both typical and atypical pathogens. The antibiotic selected should have an excellent side-effect profile and be relatively inexpensive. Clinicians should be selective in their choice of antibiotic for CAP and choose an antimicrobial that has little or no resistance potential, is relatively inexpensive, and permits i.v.-to-PO switch monotherapy.

Prevalence of lower respiratory tract infections in hospitalized patients in the United Kingdom and Eire--results from the Second National Prevalence Survey

During 1993 and 1994, the Hospital Infection Society conducted its Second National Prevalence Survey of infections in patients in British hospitals. The prevalence rates for hospital-acquired (HA) and community-acquired (CA), lower respiratory tract infections (LRTIs) were 2.4% and 6.1%, respectively; this shows an increase over that reported in the First National Prevalence Study. The prevalence rate of HA infections for ventilated patients was 18.6%. The prevalence was greater in males, odds ratio (OR, 95% CI) for HA-LRTIs (1.4, 1.1-1.6) and CA-LRTIs (1.2, 1.1-1.3) than in females. In the case of both HA-LRTIs and CA-LRTIs, there was an increase in prevalence in patients with age >75 years, (HA-LRTIs 1.7, 1.3-2.2; CA-LRTIs 1.7, 1.0-2.7). Results of multivariable logistic regression analysis showed an increased risk of HA-LRTIs in patients who had a nasogastric tube (3.6, 2.3-3.6), were ventilated (2.3, 1.6-3.2), trauma patients (2.2, 1.5-3.0), chronic obstructive airway disease (COAD), (1.9, 1.5-2.3), a tracheostomy (1.9, 1.3-2.7), prior blood transfusion (1.5, 1.2-1.8), smokers (1.4, 1.1-1.6) or on systemic corticosteroid therapy (OR 1.3, 1.1-1.6). Community-acquired LRTIs were positively associated with cystic fibrosis (33.7, 19.1-59.3), HIV (9.8, 6.5-14.8), COAD (4.8, 3.8-4.8), systemic corticosteroid therapy (2.5, 2.2-2.8), tracheostomy (1.8, 1.1-2.9), males (1.2, 1.1-1.3) and smoking (1.2, 1.1-1.4).

Community-acquired pneumonia

Community-acquired pneumonia (CAP) remains a leading cause of morbidity and mortality worldwide and has significant financial implications for health-care systems. The epidemiology and fundamental biology of the disease has evolved, reflecting the human immunodeficiency virus pandemic, increasing world travel, and, as always, poverty. The promise held out by molecular diagnostic technology has yet to deliver in this arena, and antibiotic resistance continues to drive the quest for new antimicrobial agents. The emergence of multidrug-resistant Streptococcus pneumoniae, the microorganism most often implicated as a cause of CAP, continues to threaten treatment options. The evolution of this organism, the persistently high mortality rate associated with CAP, and increasing health-care costs have prompted the publication of guidelines by various authorities that can be used to assist in the initial assessment of the patient and then guide empirical antimicrobial therapy. It is unclear whether these guidelines will have significant impact on cost and mortality, although the trend toward a rational and evidence-based approach to antimicrobial therapy must be a goal to aspire to.

Pneumonia: the impact of antibiotic resistance on its management

Pneumonia in the community affects between 1 and 5 per 1000 per year. The microbial aetiology is diverse and influenced by preexisting disease, seasonality, as well as animate and inanimate environmental sources; pneumococci, Legionella spp., Mycoplasma pneumoniae, and more recently Chlamydia pneumoniae are the predominant bacterial pathogens. Gram-negative enteric bacteria although less common are particularly virulent. Antibiotic resistance is well established for Haemophilus influenzae and Gram-negative bacillary infections, but has been a recent phenomenon in the case of Streptococcus pneumoniae, which is numerically the leading pathogen. Despite the concerns raised by this reduced susceptibility to penicillin, evidence that this has been translated into increased clinical failures is currently difficult to establish. Macrolide and tetracycline resistance among pneumococci is more common. beta-Lactamase production by H. influenzae has now reached levels where, in those with severe pneumonia, beta-lactamase stable agents are preferred. Consensus Guidelines on the treatment of community acquired pneumonia have been published by the British Thoracic Society, the American Thoracic Society, and from Expert Panels in Canada and France. These emphasize severity assessment and differentiate management in the community or hospital setting. The recommended regimens are compared and contrasted. In conclusion, mild/moderate pneumonia, when pneumococcal in nature, is likely to still respond to amoxycillin or penicillin G, but in higher dosages where pneumococcal resistance is documented. However, in severe infection where pneumococcal resistance, other beta-lactamase-producing pathogens, or an atypical infection could be operating, it is important that initial empirical therapy be broad spectrum and promptly administered. Treating multiresistant pneumococcal disease in those allergic to beta-lactams presents a particular dilemma. Glycopeptides are currently preferred.

Use of a treatment protocol in the management of community-acquired lower respiratory tract infection

The aim of the present study was to examine the impact of an antimicrobial prescribing protocol on clinical and economic outcome measures in hospitalized patients with community-acquired lower respiratory tract infection (LRTI). The study was performed as a prospective controlled clinical trial within the medical wards at Antrim Area Hospital, Northern Ireland. Data were collected on all hospitalized adult patients with a primary diagnosis of LRTI during the period December 1994 to February 1995 (normal hospital practice; control group; n = 112). After an LRTI management protocol (medical, microbiological and pharmacy staff) had been developed, all hospitalized adult patients with a primary diagnosis of LRTI over the period December 1995 to February 1996 formed the intervention group (treated according to the protocol; n = 115). The results showed a statistically significant impact of the protocol in terms of clinical and economic outcome measures. Patients treated using the algorithmic prescribing protocol had significant reductions in length of hospital stay (geometric mean 4.5 versus 9.2 days), iv drug administration (34.8% versus 61.6%), duration of iv therapy (geometric mean 2.1 versus 5.7 days) and treatment failures (7.8% versus 31.3%). Healthcare costs were also significantly reduced. The use of the protocol was a major factor in streamlining the prescribing of antimicrobial therapy for community-acquired LRTI and led to more cost-effective patient management.

Cost-effectiveness of the pneumococcal vaccine in the United States Navy and Marine Corps

Vaccination for Streptococcus pneumoniae has been recommended for its efficacy and cost-effectiveness in elderly and immunocompromised populations. However, its use in active-duty military personnel has not been analyzed. We developed a Markov model to evaluate health and economic outcomes of vaccinating or not vaccinating all members of the active-duty cohort, measuring quality-adjusted life years (QALYs) gained, costs, and marginal cost-effectiveness. Pneumococcal pneumonia vaccination increased each person's life expectancy by 0. 03 days and decreased costs by $9.88 per person. The magnitude of the benefit of immunization is moderately sensitive to the rate of serious side effects caused by the vaccine, the incidence of pneumonia, the length of protection, and the efficacy of the vaccine. Vaccinating all 575,000 active-duty US Navy and Marine Corps members could save $5.7 million during the time the members are alive and on active duty and could provide a total gain of 54 QALYs. On the basis of these results, the military should consider expanding current guidelines to include pneumococcal vaccine immunization for all active-duty members of the military.

Evidence-based medicine: empiric antibiotic therapy in community-acquired pneumonia

A number of national society guidelines exist for empiric management of community-acquired pneumonia but these are, to a large extent, not evidence-based, but based on clinical experience, in vitro data, pragmatism and common sense. Many randomized controlled trials of antibiotic therapy in community-acquired pneumonia have been conducted, but most of these have been powered to demonstrate equivalent efficacy of new treatments in comparison with conventional antimicrobial therapy. Development of new antibiotics has been driven by the emergence of penicillin-resistant Streptococcus pneumoniae, but so far there is no hard evidence that beta-lactam therapy fails in community-acquired pneumonia, at least with the higher doses of penicillins that are commonly used in hospital practice. Nonetheless, newer antibiotics have been deployed including macrolides and quinolones, and have demonstrated equivalent (and in some cases, marginally improved) efficacy to older antibiotic treatments in randomized control trials. A number of studies have shown that it is possible to stratify patients according to severity of illness, to in-patient or out-patient management protocols. These have been validated and refined.

Diagnostic testing for community-acquired pneumonia

The microbial cause of community-acquired pneumonia can be identified by noninvasive means in the majority of cases, usually within a few days of presentation. The Gram stain and culture of a pretreatment sputum sample are the most useful tests, but have significant limitations. Methods for detecting pneumococcal antigen in respiratory secretions are particularly helpful in patients who have received antibiotics before evaluation. Testing for specific pathogens such as L. pneumophila, M. pneumoniae, or C. pneumoniae should be guided by clinical suspicion in individual circumstances. Invasive procedures are most helpful in patients suspected of having infection with opportunistic or resistant pathogens, and in those whose initial management has been unsuccessful.

Severe community-acquired pneumonia

Severe CAP is a life-threatening condition defined by the presence of respiratory failure or symptoms of severe sepsis or septic shock. It accounts for approximately 10% of hospitalized patients with CAP. The majority of patients with severe pneumonia have underlying comorbid illnesses, with COPD, alcoholism, chronic heart disease, and diabetes mellitus being the most frequent. S. pneumoniae, Legionella spp, GNEB (especially K. pneumoniae), H. influenzae, S. aureus/spp, Mycoplasma pneumoniae, respiratory viruses (especially influenza viruses), and P. aeruginosa represent the most important causative organisms of severe CAP. Rapid initiation of appropriate antimicrobial treatment is crucial for a favorable outcome. Initial antimicrobial treatment should be based on an epidemiological (empiric) approach. Microbial investigation may be helpful in the individual case but is probably more useful to define local antimicrobial policies based on local epidemiologic and susceptibility patterns. Mortality rates range from 21% to 54%. The most important prognostic factors include general health state of the patient, appropriateness of initial antimicrobial treatment, and the existence of bacteremia, as well as factors reflecting severe respiratory failure, severe sepsis, septic hypotension or shock, and the extent of infiltrates in chest radiograph. Initial antimicrobial treatment should consist of a second (or third) generation cephalosporin and erythromycin. Modifications of this basic regimen should be considered in the presence of distinct comorbid conditions and risk factors for distinct pathogens. Promising new approaches of nonantimicrobial treatment, including noninvasive ventilation, treatment of hypoxemia, and immunomodulation, are under investigation.

Value of the polymerase chain reaction assay in noninvasive respiratory samples for diagnosis of community-acquired pneumonia

We studied the causes of community-acquired pneumonia (CAP) in 184 patients. Microbiologic evaluation included sputum examination, blood culture, assessment of acute and convalescent antibody titers for Legionella pneumophila, Mycoplasma pneumoniae, Chlamydia pneumoniae, Coxiella psitacci, Coxiella burnetii and respiratory viruses, polymerase chain reaction (PCR) assays for M. pneumoniae and C. pneumoniae in throat swab, and PCR assay based on the amplification of pneumolysin gene fragment in sera. The causative pathogen was identified in 78 patients (Streptococcus pneumoniae, 44; M. pneumoniae, 26; C. pneumoniae, 1; others, 7). S. pneumoniae was detected in serum by the PCR assay in 41 patients, five of whom also had a positive blood culture. PCR assay was negative in two patients with positive blood culture for S. pneumoniae. C. pneumoniae was detected by PCR in nine patients, but only one showed seroconversion. M. pneumoniae was detected by PCR in only three patients (two without seroconversion). The diagnosis of pneumonia caused by S. pneumoniae was five times greater using PCR in serum than with blood culture. Detection of C. pneumoniae by PCR without fulfilling criteria for acute infection may be considered a prior infection. The PCR assay for the diagnosis of M. pneumoniae has a lower sensitivity than serologic methods.

Is Streptococcus pneumoniae the leading cause of pneumonia of unknown etiology? A microbiologic study of lung aspirates in consecutive patients with community-acquired pneumonia

PURPOSE

Although a wide variety of recognized pathogens can cause community-acquired pneumonia, in many patients the etiology remains unknown after routine diagnostic workup. The aim of this study was to identify the causal agent in these patients by obtaining lung aspirates with transthoracic needle aspiration.

SUBJECTS AND METHODS

During a 15-month period, all consecutive patients with community-acquired pneumonia who were eligible for transthoracic needle aspiration were enrolled in the study. In addition to conventional microbial methods (culture of blood and sputum, serologic studies), we performed cultures and genetic and antigen tests for common respiratory pathogens in lung aspirates.

RESULTS

The study group consisted of 109 patients. Conventional microbial studies identified an etiology in 54 patients (50%), including Mycoplasma pneumoniae in 19 patients, Chlamydia pneumoniae in 9 patients, and Streptococcus pneumoniae in 9 patients. Among the remaining 55 patients, study of the lung aspiration provided evidence of the causal agent in 36 (65%). In 4 additional patients with a single microbial diagnosis by conventional methods, the lung sample provided evidence of an additional microorganism. The new pathogens detected by lung aspiration were S. pneumoniae in 18 patients, Haemophilus influenzae in 6 patients, Pneumocystis carinii in 4 patients, and C. pneumoniae in 3 patients; other organisms were identified in 4 patients.

CONCLUSIONS

In our study, S. pneumoniae was the leading cause of community-acquired pneumonia, accounting for 25% of all cases, including about one-third of the cases the cause of which could not be ascertained with routine diagnostic methods.

Utility of blood cultures in community-acquired pneumonia requiring hospitalization: influence of antibiotic treatment before admission

It has been previously shown that antibiotics given before hospitalization significantly reduce the proportion of positive blood cultures in community-acquired pneumonia (CAP). The aim of this prospective study was to compare the utility and cost-benefits of blood cultures in patients, hospitalized for moderate CAP, who had or had not received antibiotic therapy prior to admission. During 1 year, 53 patients were included and separated into two groups: group 1 patients had not received antibiotic treatment prior to admission (n = 30), whereas group 2 patients had been treated with antibiotics (n = 23). Within the first 48 hours, a set of blood cultures was collected if the body temperature was higher than 38.5 degrees C or in the case of shaking chills. A total of 136 blood cultures was collected; 74 in group 1 and 62 in group 2. Bacteraemia was significantly more frequent in group 1 than in group 2, 5/30 patients vs. 0/23, respectively (P < 0.05). The cost of negative blood cultures was valued at 13,939.2 FF in group 1 and 13,164.8 FF in group 2, respectively 464.6 +/- 244.3 FF and 569.3 +/- 233.4 FF per patient (n.s.). Moreover, blood cultures were the method of diagnosis in only one of the five patients with bacteraemia and in no case did a positive blood-culture result influence the initial therapeutic regime. Thus, our results suggest a reduced clinical utility and cost-benefit of blood cultures in patients hospitalized for moderate CAP who have received an antibiotic treatment prior to admission.

Pulmonary infiltrates in neutropenic patients with acute leukemia during chemotherapy: outcome and prognostic factors

STUDY OBJECTIVE

To determine predictors of mortality from pulmonary infiltrates in neutropenic patients with acute leukemia during chemotherapy, and the significance of those factors related to the underlying malignancy and its therapy as well as of those related to the severity of the illness associated with pulmonary infiltrates.

DESIGN

A historical cohort study.

SETTING

A university teaching hospital and tertiary referral center.

PATIENTS AND METHODS

Overall, 53 patients with neutropenia during chemotherapy and with first episodes of pulmonary infiltrates during a 4-year period were studied. Prognostic analysis included 38 variables. Multivariate analyses were performed by logistic regression.

RESULTS

The survival rate from pneumonia was 57% (30/53). The following eight parameters were significantly associated with death in univariate analysis: comorbidity present; development of "late" pulmonary infiltrates (> or = 14 days after hospital admission); heart rate > or = 100 beats/min; a ratio heart rate/systolic blood pressure (HR/SBP) > or = 1.2; urea nitrogen > 7 mmol/L; radiographic score > or = 3; neutropenia < 1.0x10(9)/L at the treatment end point; and failed complete remission. In a multivariate model including only parameters available at diagnosis of pulmonary infiltrates, the presence of a ratio HR/SBP > or = 1.2 and of a radiographic score > or = 3 remained independently associated with death. In a second model also including the evolutionary parameter neutropenia < or = 1.0x10(9)/L at the treatment end point, both parameters remained significant together with neutropenia <1.0x 10(9)/L at the treatment end point. The presence of a ratio HR/SBP > or = 1.2 was a strong marker of early death.

CONCLUSION

Both therapy- and malignancy-associated neutropenia as well as the severity of illness associated with pulmonary infiltrates are independent prognostic factors. Patients with a ratio HR/SBP > or = 1.2 at diagnosis of pulmonary infiltrates suffer from potentially reversible acute illness, are at risk for early death and, therefore, may be appropriate candidates for treatment in an ICU.

Severe community-acquired pneumonia

Community-acquired pneumonia (CAP) is likely to be severe in the very elderly, and clinically significant in those with hepatic/ renal insufficiency, cardiopulmonary disease, or, impaired host defenses. Pathogens in mild, moderately severe, and severe CAP are the same. These pathogens determine prognosis, complications, and duration of therapy. Empiric antimicrobial therapy should be based on likely pathogens, not severity of illness which affects the potency but not spectrum of antibiotic selected.

Practical considerations and guidelines for the management of community-acquired pneumonia

Community-acquired pneumonia (CAP) is a common condition which has a significant mortality. The management of a patient with CAP is centred around assessment and correction of gas exchange and fluid balance together with administration of appropriate antibiotics. Up to 10 different pathogens regularly cause CAP, of which Streptococcus pneumoniae is the most important. These different pathogens cannot be distinguished by clinical features or simple laboratory tests. Microbiological tests are slow and insensitive, so empirical therapy is necessary, at least initially. Accurate assessment of illness severity is the most important factor determining initial management, since this assists the decision of whether to admit the patient to hospital in addition to guiding antibiotic choice and route of administration. Two different approaches to severity assessment are outlined. Our antibiotic recommendation for empirical therapy for the patient managed at home and the previously fit patient admitted to hospital is amoxicillin. Amoxicillin/clavulanate plus a macrolide is our choice for the severely ill previously fit patient and a third-generation cephalosporin plus a macrolide is recommended for the severely ill patient with comorbidity. Alternative pathogens and specific treatment regimens are also described. There may be several causes of treatment failure, and in patients who fail to respond to therapy, it is essential to review all the initial clinical and laboratory information, which if necessary must be repeated.

Microbiological and clinical aspects of infection associated with Stenotrophomonas maltophilia

The gram-negative bacterium Stenotrophomonas maltophilia is increasingly recognized as an important cause of nosocomial infection. Infection occurs principally, but not exclusively, in debilitated and immunosuppressed individuals. Management of S. maltophilia-associated infection is problematic because many strains of the bacterium manifest resistance to multiple antibiotics. These difficulties are compounded by methodological problems in in vitro susceptibility testing for which there are, as yet, no formal guidelines. Despite its acknowledged importance as a nosocomial pathogen, little is known of the epidemiology of S. maltophilia, and although it is considered an environmental bacterium, its sources and reservoirs are often not readily apparent. Molecular typing systems may contribute to our knowledge of the epidemiology of S. maltophilia infection, thus allowing the development of strategies to interrupt the transmission of the bacterium in the hospital setting. Even less is known of pathogenic mechanisms and putative virulence factors involved in the natural history of S. maltophilia infection and this, coupled with difficulties in distinguishing colonization from true infection, has fostered the view that the bacterium is essentially nonpathogenic. This article aims to review the current taxonomic status of S. maltophilia, and it discusses the laboratory identification of the bacterium. The epidemiology of the organism is considered with particular reference to nosocomial outbreaks, several of which have been investigated by molecular typing techniques. Risk factors for acquisition of the bacterium are also reviewed, and the ever-expanding spectrum of clinical syndromes associated with S. maltophilia is surveyed. Antimicrobial resistance mechanisms, pitfalls in in vitro susceptibility testing, and therapy of S. maltophilia infections are also discussed.

An analysis of decisions by European general practitioners to admit to hospital patients with lower respiratory tract infections. The European Study Group of Community Acquired Pneumonia (ESOCAP) of the European Respiratory Society

BACKGROUND

The purpose of this study was to identify factors on which European general practitioners (GPs) base their decisions to admit to hospital patients with lower respiratory tract infections (LRTI).

METHODS

A survey was carried out from December 1993 to January 1994 to identify factors that affect GPs' decisions to admit to hospital patients with LRTI by collecting data on 2056 patients from 605 GPs in France, Germany, Italy, Spain, and the UK.

RESULTS

Only 93 (4.5%) of the patients included in the study were admitted to hospital. Univariate analysis showed that age > 60 years, institutionalisation of the patient, concomitant diseases, cardiac insufficiency, asthma, a diagnosis of pneumonia, and clinical signs such as chest pain, cyanosis, tachypnoea and hypotension significantly (odds ratio (OR) > 2.0, p < 0.002) influenced the decision to admit to hospital. No influence could be shown for sex, smoking habits, history of bronchiectasis or chronic bronchitis, the presence of fever, chills, myalgia, cough or purulent sputum, and the diagnoses of acute bronchitis, influenza or exacerbation of chronic bronchitis. In the multivariate analysis only the presence of chest pain (OR 2.3, 95% confidence interval (CI) 1.5 to 3.5), cyanosis (OR 4.1, 95% CI 2.4 to 7.1), dyspnoea (OR 4.9, 95% CI 3.1 to 7.9), and hypotension (OR 2.9, 95% CI 1.6 to 5.2), as well as a diagnosis of pneumonia (OR 6.6, 95% CI 4.3 to 10) (all p < 0.00001) remained as factors that significantly affected the decision to admit to hospital.

CONCLUSIONS

Clinical signs of severe infection and a diagnosis of pneumonia are the main factors that induce GPs to admit patients with LRTI to hospital in Europe.

Community acquired pneumonia: aetiology and usefulness of severity criteria on admission

BACKGROUND

Community acquired pneumonia remains an important cause of hospital admission and carries an appreciable mortality. Criteria for the assessment of severity during admission have been developed by the British Thoracic Society (BTS). A study was performed to determine the sensitivity and specificity of a severity rule based on a modification of the BTS prognostic rules applied on admission, to compare severity as assessed by medical staff with the modified rule, and to determine the microbiological cause of community acquired pneumonia in Christchurch.

METHODS

A 12 month study of all adults admitted to Christchurch Hospital with community acquired pneumonia was undertaken. Three hundred and sixteen consecutive patients with suspected community acquired pneumonia were screened for inclusion. Variables obtained from the history, examination, investigations, and initial treatment were examined for association with mortality.

RESULTS

Two hundred and fifty five patients met the inclusion criteria. Their mean age was 58 years (range 18-97). A microbiological diagnosis was made in 181 cases (71%), Streptococcus pneumonia (39%), Mycoplasma pneumoniae (16%), Legionella species (11%), and Haemophilus influenzae (11%) being the most commonly identified organisms. Patients had a 36-fold increased risk of death if any two of the following were present on admission: respiratory rate > or = 30/min, diastolic BP < or = 60 mm Hg, urea > 7 mmol/l, or confusion. The severity rule identified 19 of the 20 patients who died and six of eight patients admitted to the intensive care unit as having life threatening community acquired pneumonia. The sensitivity of the modified rule for predicting death was 0.95 and the specificity 0.71. In 47 cases (21%) the clinical team appeared to underestimate the severity of the illness.

CONCLUSIONS

The organisms responsible for community acquired pneumonia in Christchurch are similar to those reported from other centres except for Legionella species which were more common than in most studies. The modification of the BTS prognostic rules applied as a severity indicator at admission performed well and could be incorporated into management guidelines.

Economic evaluation of vaccination against influenza in New Zealand

The objective of this study was to evaluate the costs and benefits of influenza vaccination for the population aged 65 years and over, from the perspectives of individuals and health insurers, government and society. The annual incremental direct medical costs and benefits of influenza vaccination (compared with the nonvaccination, or 'do nothing', option) were evaluated using New Zealand healthcare resource usage and unit cost data [in 1992 New Zealand dollars ($NZ); $NZ1 = $US0.5458, June 1992] applied to cohort studies reported in the literature. The costs and benefits to society as a result of vaccination of people aged 65 years and older (20% of people in this age group are currently vaccinated) were estimated to be: (i) additional direct medical costs of vaccination of $NZ1.42 million [$NZ17.78 per vaccination]; (ii) direct medical costs avoided of $NZ5.35 million ($NZ67.18 per vaccination); and (iii) net benefits of $NZ3.93 million ($NZ49.40 per vaccination). The direct medical costs avoided per dollar cost of vaccination were $NZ1.04 for individuals, $NZ4.69 for government and $NZ3.78 for society as a whole. If the vaccination uptake for this group is increased in 20% increments, the net benefit to society increases by a further $NZ3.93 million per year at each step. If the economic evaluation is extended to include vaccination of at-risk individuals under 65 years of age, net benefits to society increase by 15%. Influenza vaccination for people aged 65 years and over is cost effective from the perspective of society, government and the individual. If the vaccination rate for at-risk individuals in New Zealand could be increased to 60%, the net benefits reported in this study would increase by 200%. However, the costs of promotion and education to achieve this vaccination rate would need to be deducted from the net benefits. Strategies to increase the vaccination rate include altering the cost of vaccinations to the individual, intensifying education and promotion programmes, and changing the mode of delivery.

Epidemiology of lower respiratory tract infections

The aim of this review is to focus on the epidemiology of lower respiratory tract infections, the etiology, prognosis and risk factors, dividing these problems into the following issues: global impact of these afflictions, community-acquired pneumonia, hospital acquired pneumonia, respiratory infections in surgery, acute bronchitis and exacerbations of chronic bronchitis. Every year about 5 million people die of acute respiratory infections. Among these, pneumonia represents the most frequent cause of mortality, hospitalization and medical consultation. Several factors (age, underlying disease, environment) influence mortality, morbidity and also microbial etiology. The authors also refer to recent data on the most frequently identified antibiotic resistance of respiratory pathogens. The knowledge of such different clinico-epidemiological situations is essential to physicians for an effective approach to treatment of pneumonia and bronchitis.