Clinical presentation of community-acquired Chlamydia pneumoniae pneumonia in adults

STUDY OBJECTIVE: To investigate the clinical presentation of community-acquired Chlamydia pneumoniae pneumonia in adults. DESIGN: Prospective study. SETTING: Kawasaki Medical School Hospital, Kawasaki Medical School Kawasaki Hospital, and Kurashiki Daiichi Hospital in Japan. PARTICIPANTS: Forty patients with community-acquired pneumonia with C pneumoniae as the only pathogen identified admitted to three hospitals between April 1996 and March 2001 and their clinical presentations were compared to patients with Streptococcus pneumoniae and Mycoplasma pneumoniae pneumonia. MEASUREMENTS: The diagnosis of C pneumoniae infection was based on isolation and serologic testing of antibodies by the microimmunofluorescence test. RESULTS: The clinical presentations, except for shortness of breath, were similar for the three major etiologic agents. The mean temperature of C pneumoniae patients on hospital admission was 37.9 degrees C, which was lower than that of patients with S pneumoniae and M pneumoniae. The mean WBC count on hospital admission was lower in the patients with C pneumoniae (mean, 9,100/microL) than in those with S pneumoniae pneumonia but higher than in those with M pneumoniae pneumonia. No patients required respiratory support or admission to an ICU, and no deaths occurred among the C pneumoniae pneumonia patients. CONCLUSIONS: Our results indicate that C pneumoniae pneumonia as a single etiologic agent is mild and that the underlying conditions and clinical symptoms closely resemble those of S pneumoniae pneumonia. However, the physical examinations, laboratory findings, and prognostic factors of the C pneumoniae patients resembled those of patients with M pneumoniae pneumonia.     

Resource utilization of adults admitted to a large urban hospital with community-acquired pneumonia caused by Streptococcus pneumoniae

OBJECTIVE: To determine if penicillin-nonsusceptible Streptococcus pneumoniae, among other variables, was significantly associated with greater hospital costs among patients with community-acquired pneumonia (CAP). DESIGN: Retrospective, cohort study. SETTING: Eight hundred ten-bed, urban, private, teaching hospital. PATIENTS: Adult patients admitted between 1999 and 2003 with CAP caused by S pneumoniae. INTERVENTION: Clinical criteria and costs (inflated to 2004 dollars) were collected from the medical charts and detailed hospital bills for each individual patient. Costs were compared according to classification by penicillin susceptibility. Multivariate linear regression was utilized to determine variables independently associated with increased hospital costs and length of stay. RESULTS: Of 168 patients included, 44 patients (26%) had CAP caused by penicillin-nonsusceptible S pneumoniae. Median total hospital costs were 8,654 dollars (25th to 75th percentile, 5,457 dollars to 16,027 dollars), with no difference between susceptible and nonsusceptible groups. Bed costs accounted for 55.6% of total costs, followed by laboratory (9.9%) and pharmacy (9.8%) costs. Regression analyses determined that ICU admission (p < 0.001), unexplained delays in discharge (p = 0.001), and neoplasm (p < 0.04) were independently predictive of both total hospital costs (adjusted r2 = 0.46) and increasing length of stay (adjusted r2 = 0.30). Hospital mortality, bacteremia, and congestive heart failure were also associated with at least one of the dependent variables. CONCLUSION: In the current era in which more potent antibiotics are empirically utilized to treat CAP, it does not appear that a simple classification of penicillin nonsusceptibility complicates the economic impact of S pneumoniae infection. Focused efforts to reduce length of stay, including minimizing prolonged and unnecessary observation of patients, should have the most profound effect on reducing total costs.     

Antimicrobial susceptibilities of Streptococcus pneumoniae isolated from adult patients with community-acquired pneumonia in Japan

Background and objective:   Streptococcus pneumoniae ( S. pneumoniae ) is the most common pathogen associated with community-acquired pneumonia and its resistance to antimicrobials is a worldwide problem. The aim of this study was to investigate the current drug susceptibilities of S. pneumoniae isolated from adult patients with community-acquired pneumonia in Japan.
Methods:   S. pneumoniae strains isolated from adult patients with pneumococcal pneumonia from 10 institutions were collected prospectively between May 2003 and October 2004 and tested for drug susceptibilities. Clinical data were analysed and the risk factors for drug resistance investigated.
Results:   A total of 141 isolates of S. pneumoniae were analysed. Of these S. pneumoniae isolates, 46.1% had intermediate penicillin resistance and the minimum inhibitory concentration (MIC) occurring in the greatest number of isolates and MIC90 value was 2 μg/mL. The prevalence of resistance to macrolides was 80%, with the MIC90 values being greater than or equal to 16 μg/mL. Approximately 40% of the strains were resistant to oral third-generation cephems. Penicillin and erythromycin resistance were both associated with the pre-existing chronic disease states.
Conclusions:   The cephem and macrolide resistance of S. pneumoniae was higher than penicillin resistance in adult patients with community-acquired pneumococcal pneumonia in Japan. We recommend that bacterial identification and sensitivities are determined in areas where the macrolide resistance to S. pneumoniae is high.     

Efficacy of oral telithromycin in community-acquired pneumonia caused by resistant Streptococcus pneumoniae

The efficacy of oral telithromycin 800mg once daily for 7 days was evaluated in a multicentre, multinational study in patients with community-acquired pneumonia caused by Streptococcus pneumoniae resistant to penicillin and/or erythromycin. Per-protocol clinical and bacteriological outcomes were assessed 10-17 days post-therapy. Of the 129 patients with S. pneumoniae infection, 16 were infected with strains resistant to penicillin and/or erythromycin. Fifteen of these 16 patients (93.8%) were assessed as clinically and bacteriologically cured at the post-therapy visit.     

Macrolide-resistant Mycoplasma pneumoniae in adolescents with community-acquired pneumonia

ABSTRACT: BACKGROUND: Although the prevalence of macrolide-resistant Mycoplasma pneumoniae isolates in Japanese pediatric patients has increased rapidly, there have been no reports concerning macrolideresistant M. pneumoniae infection in adolescents aged 16 to 19 years old. The purpose of this study was to clarify the prevalence and clinical characteristics of macrolide-resistant M. pneumoniae in adolescent patients with community-acquired pneumonia. METHODS: A total of 99 cases with M. pneumoniae pneumonia confirmed by polymerase chain reaction (PCR) and culture were analyzed. Forty-five cases were pediatric patients less than 16 years old, 26 cases were 16 to 19-year-old adolescent patients and 28 cases were adult patients. Primers for domain V of 23S rRNA were used and DNA sequences of the PCR products were compared with the sequence of an M. pneumoniae reference strain. RESULTS: Thirty of 45 pediatric patients (66%), 12 of 26 adolescent patients (46%) and seven of 28 adult patients (25%) with M. pneumoniae pneumonia were found to be infected with macrolide-resistant M. pneumoniae (MR patients). Although the prevalence of resistant strains was similar in pediatric patients between 2008 and 2011, an increase in the prevalence of resistant strains was observed in adolescent patients. Among 30 pediatric MR patients, 26 had an A-to-G transition at position 2063 (A2063G) and four had an A-to-G transition at position 2064 (A2064G). In 12 adolescent MR patients, 10 showed an A2063G transition and two showed an A2064G transition, and in seven adult MR patients, six showed an A2063G transition and one showed an A2064G transition. CONCLUSIONS: The prevalence of macrolide-resistant M. pneumoniae is high among adolescent patients as well as pediatric patients less than 16-years old. To prevent outbreaks of M. pneumoniae infection, especially macrolide-resistant M. pneumoniae, in closed populations including among families, in schools and in university students, physicians should pay close attention to macrolide-resistant M. pneumoniae.     

肺炎链球菌尿抗原测定方法用于成人社区获得性肺炎快速诊断的研究

目的了解肺炎链球菌尿抗原测定方法用于快速诊断成人社区获得性肺炎的临床意义及在基层医院推广价值。方法收集2014-03~2015-04吉林省人民医院、前郭县人民医院及长春市二道区医院成人社区获得性肺炎住院患者102例尿标本,用免疫层析法测定肺炎链球菌尿抗原,同时对67例患者进行痰培养和23例患者血培养与鉴定。结果 102例患者尿肺炎链球菌抗原阳性率为15.69%(16/102),肺炎链球菌痰培养阳性率为2.99%(2/67),血培养表皮葡萄球菌阳性率为4.35%(1/23),病原体总检出率为19.61%(20/102)。结论尿抗原测定方法明显提高肺炎链球菌所致成人社区获得性肺炎的检出率,对肺炎链球菌成人社区获得性肺炎的快速诊断具有良好的应用前景,尤其在基层医院具有推广价值。     

Comparative study of community-acquired pneumonia caused by Streptococcus pneumoniae, Legionella pneumophila or Chlamydia pneumoniae

The objective of this study was to compare epidemiological data and clinical presentation of community-acquired pneumonia (CAP) caused by Streptococcus pneumoniae, Legionella pneumophila or Chlamydia pneumoniae. From May 1994 to February 1996, 157 patients with S. pneumoniae (n = 68), L. pneumophila (n = 48) and C. pneumoniae (n = 41) pneumonia with definitive diagnosis, were prospectively studied. The following comparisons showed differences at a level of at least p < 0.05. Patients with S. pneumoniae pneumonia had more frequently underlying diseases (HIV infection and neoplasm) and those with C. pneumoniae pneumonia were older and had a higher frequency of chronic obstructive pulmonary disease (COPD), while L. pneumophila pneumonia prevailed in patients without comorbidity, but with alcohol intake. Presentation with cough and expectoration were significantly more frequent in patients with S. pneumoniae or C. pneumoniae pneumonia, while headache, diarrhoea and no response to betalactam antibiotics prevailed in L. pneumophila pneumonia. However, duration of symptoms > or = 7 d was more frequent in C. pneumoniae pneumonia. Patients with CAP caused by L. pneumophila presented hyponatraemia and an increase in CK more frequently, while AST elevation prevailed in L. pneumophila and C. pneumoniae pneumonia. In conclusion, some risk factors and clinical characteristics of patients with CAP may help to broaden empirical therapy against atypical pathogens until rapid diagnostic tests are available.     

Epidemiology of community-acquired pneumonia in older adults: a population-based study

OBJECTIVE: This study assessed incidence, aetiology, clinical outcomes and risk factors for community-acquired pneumonia (CAP) in older adults. METHODS: This was a population-based cohort study that included 11,241 community-dwelling individuals aged 65 years or more, who were followed between 2002 and 2005 in the region of Tarragona, Spain. Primary endpoints were all-cause CAP (hospitalised and outpatient) and 30-day mortality after the diagnosis. All cases were radiographically proved and validated by checking clinical records. RESULTS: Incidence rate of overall CAP was 14 cases per 1000 person-years (10.5 and 3.5 for hospitalised and outpatient cases, respectively). Incidence was almost three-fold higher among immunocompromised patients (30.9 per 1000) than among immunocompetent subjects (11.6 per 1000). Maximum incidences were observed among patients with chronic lung disease and long-term corticosteroid therapy (46.5 and 40.1 cases per 1000 person-years, respectively). Overall 30-day case-fatality rate was 12.7% (2% in cases managed as outpatient and 15% in hospitalised patients). Among 358 patients with an aetiological work-up, a total of 142 pathogens were found (single pathogen in 121 cases and mixed pathogens in 10 cases). Streptococcus pneumoniae was the most common pathogen (49%), followed by Pseudomonas aeruginosa (15%), Chlamydia pneumoniae (9%) and Haemophilus influenzae (6%). In multivariable analysis, the variables most strongly associated with increasing risk of CAP were history of hospitalisation for CAP in the previous 2 years and presence of any chronic lung disease. CONCLUSIONS: CAP remains a major cause of morbidity and mortality in older adults. Incidence rates in this study largely doubled prior rates reported in Southern European regions.     

Influenza vaccination and risk of mortality among adults hospitalized with community-acquired pneumonia

BACKGROUND: Influenza vaccination has been shown to reduce illness and all-cause mortality in vulnerable populations through the prevention of influenza infection. Attenuation of the severity of illness by vaccination has been reported for respiratory tract infections due to bacterial pathogens and would represent an important additional health benefit of influenza vaccination. We evaluated the impact of prior influenza vaccination on in-hospital mortality and other health outcomes among hospitalized adults with community-acquired pneumonia (CAP). METHODS: Consecutive individuals hospitalized with CAP during "influenza season" (November to April, 1999-2003) at hospitals operated by Tenet HealthCare were identified using a database constructed to improve quality of patient care. Associations between vaccination status and all-cause in-hospital mortality were evaluated using logistic regression models. RESULTS: Among 17 393 adults hospitalized with CAP during the study period, 1590 (19% of those with recorded vaccine status) had a history of influenza vaccination in the current or most recent influenza season. Vaccine recipients were less likely to die in hospital of any cause than individuals without vaccination (odds ratio, 0.30; 95% confidence interval, 0.22-0.41). These effects remained significant after adjustment for the presence of comorbid illnesses and pneumococcal vaccination (adjusted odds ratio for death, 0.61; 95% confidence interval, 0.43-0.87) and under widely varying assumptions about individuals with missing vaccination status. CONCLUSIONS: Prior influenza vaccination was associated with improved survival in hospitalized patients with CAP during influenza season. This observation, if confirmed by other studies, would represent an important additional benefit of enhanced influenza vaccine coverage.     

Severe community-acquired pneumonia in adults

Patients with severe community acquired pneumonia (CAP) need continuous surveillance and monitoring at intensive care units (ICU), where they can receive specialized support as mechanical ventilation and/or hemodynamic support. Patients that require ICU admittance represent 10 to 30% of all patients interned because a pneumonia. In this category, high complication rate, prolonged hospital stay and high mortality rate are the rule. The American Thoracic Society (ATS) criteria for severe pneumonia establishes the following main criteria: necessity of mechanical ventilation and presence of septic shock; minor criteria: systolic blood pressure < 90 mmHg, radiological multilobar involvement and PaO2/FiO2 < 250 mmHg. British Thoracic Society (BTS) criteria for severe CAP are: respiratory rate over 30 breaths/min, diastolic blood pressure under 60 mmHg, BUN > 20 mg/dl and mental confusion. In all patients with CAP it is recommended the evaluation of its severity at admission. This evaluation should be done in conjunction with an experienced physician, and if criteria for poor prognosis are met, an early admission to ICU is recommended. ATS and BTS modified criteria (CURB) are useful in this procedure. In severely ill patients with CAP it is recommended to perform the following microbiological analysis: sputum Gram stain and culture, blood culture, pleural fluid Gram stain and culture, if present and tapped, Legionella pneumophila urine antigen test, influenza A and B antigen detection tests (epidemic period: autumn and winter), and serology for atypical bacteria (Mycoplasma pneumoniae and Chlamydia pneumoniae).     

Early switch from intravenous to oral antibiotics in hospitalized patients with bacteremic community-acquired Streptococcus pneumoniae pneumonia

BACKGROUND: The identification of Streptococcus pneumoniae bacteremia in hospitalized patients with community-acquired pneumonia is considered by some investigators to be an exclusion criterion for early switch from intravenous to oral therapy. OBJECTIVE: To determine whether the switch from intravenous to oral therapy in such patients, once the bx;1patient reaches clinical stability, is associated with poor clinical outcome. METHODS: The medical records of 400 patients with community-acquired pneumonia hospitalized at the Veterans Affairs Medical Center of Louisville (Louisville, Ky) were reviewed to identify patients with bacteremic S pneumoniae. Four criteria were used to define when a patient reached clinical stability and should be considered a candidate for switch therapy: (1) cough and shortness of breath are improving, (2) patient is afebrile for at least 8 hours, (3) white blood cell count is normalizing, and (4) oral intake and gastrointestinal tract absorption are adequate. RESULTS: A total of 36 bacteremic patients were identified. No clinical failures occurred in 18 patients who reached clinical stability and were switched to oral therapy or in 7 patients who reached clinical stability and continued intravenous therapy. Clinical failures (5 deaths) occurred in the group of 11 patients who did not reach clinical stability. CONCLUSION: Once a hospitalized patient with community-acquired pneumonia reaches clinical stability, it is safe to switch from intravenous to oral antibiotics even if bacteremia caused by S pneumoniae was initially documented.     

Mycoplasma pneumoniae and Chlamydophila pneumoniae in children with community-acquired pneumonia in Thailand.

BACKGROUND: The prevalence of community-acquired pneumonia (CAP) caused by atypical pathogens in Thai children is unknown. OBJECTIVE: To examine the prevalence of Mycoplasma pneumoniae and Chlamydophila pneumoniae infections in paediatric patients (aged 2-15 years) with CAP in three academic hospitals using standardised laboratory techniques. The characteristics of atypical pneumonia were also compared with other causes of CAP. METHODS: Diagnosis of current infection was based on a four-fold or more rise in antibody serum samples or persistently high antibody titres together with the presence of mycoplasmal or chlamydial DNA in secretions. RESULTS: Of 245 patients with CAP, 17.5% of cases were caused by atypical pathogens (M. pneumoniae 14.3%, C. pneumoniae 2.8% and co-infection 0.4%). We also found atypical pathogens in young children aged 2-5 years. The clinical and laboratory findings did not distinguish atypical pneumonia from other CAPs. Segmental or lobar consolidation on chest X-rays was more common in atypical pneumonia, while dyspnoea was more prominent in other CAPs. CONCLUSION: Our data show a high prevalence of M. pneumoniae and C. pneumoniae in Thai children with CAP, including in children aged 2-5 years.     

Bacterial community-acquired pneumonia in older patients

Pneumonia in the elderly remains a major source of morbidity and mortality in an age group that is growing in numbers. It remains unclear whether the propensity of older adults to develop community-acquired pneumonia represents an aging of host defenses, secondary effects of comorbid disease, or both. The signs and symptoms of pneumonia in the elderly are more subtle than in younger populations, which may lead to a delay in diagnosis. Although therapy for community-acquired pneumonia in the elderly is the same as for younger populations, mortality is higher, leading to an important role for prevention.     

Interventions to prevent pneumonia among older adults

Pneumonia is a common cause of death in older people. Antimicrobial drugs do not prevent pneumonia and, because of increasingly resistant organisms, their value in curing infection will become more limited. Establishing new strategies to prevent pneumonia through consideration of the mechanisms of this devastating illness is essential. The purpose of this review is to discuss how pneumonia develops in older people and to suggest preventive strategies that may reduce the incidence of pneumonia among older adults. Aspiration of oropharyngeal bacterial pathogens to the lower respiratory tract is one of the most important risk factors for pneumonia; impairments in swallowing and cough reflexes among older adults, e.g., related to cerebrovascular disease, increase the risk for the development of pneumonia. Thus, strategies to reduce the volumes and pathogenicity of aspirated material should be pursued. For example, since both swallowing and cough reflexes are mediated by endogenous substance P, pharmacologic therapy using angiotensin-converting enzyme inhibitors, which decrease substance P catabolism, may improve both reflexes and result in the lowering of the risk of pneumonia. Similarly, since the production of substance P is regulated by dopaminergic neurons in the cerebral basal ganglia, treatment with dopamine analogs or potentiating drugs such as amantadine (and, of course, prevention of cerebral vascular disease, which can result in basal ganglia strokes) should affect the incidence of pneumonia. The purpose of this review is to consider promising pharmacologic treatments as methods of preventing pneumonia in older adults and to review other proven strategies, e.g., infection control and cerebrovascular disease prevention that will lessen the incidence of pneumonia.     

Penicillin resistance not a factor in outcome from invasive Streptococcus pneumoniae community-acquired pneumonia in adults when appropriate empiric therapy is started

BACKGROUND: Invasive Streptococcus pneumoniae pneumonia among adults due to penicillin-resistant or intermediate resistant strains was investigated to determine whether these patients responded poorly to common antibiotic regimens compared to pneumonia due to susceptible strains. METHODS: During a 21-year period (1983-2003), clinical outcome was analyzed among 3 groups of adults, 19 with resistant, 33 with intermediate, and 133 with susceptible invasive S pneumoniae pneumonia admitted to hospitals in Huntington, West Virginia. Adults with resistant and intermediate infections were matched by age and month of admission to a group of 133 adults with penicillin-susceptible infections. All isolates of resistant and intermediate infections were capsular serotypes/serogroups 6, 9, 14, 19, and 23, and isolates of susceptible infections included 24 different serotypes/serogroups. Case fatality rates were calculated for deaths that occurred during the first 7, first 14, and first 21 days of hospitalization. Minimal inhibitory concentration (MIC) was determined by E-test and capsular serotype by Quellung procedures. RESULTS: The resistant and susceptible groups did not differ in several measures of severity of illness, including admission vital signs, duration of fever, mean total leukocyte count, number of lobes involved, preexisting underlying diseases, and antibiotic treatment regimens. There were no significant differences in case fatality rates between the 3 groups of pneumonia by days in hospital, age, severity of illness, and empiric antibiotic treatment regimen with a cephalosporin and a macrolide, the most common antibiotic regimen. CONCLUSIONS: These findings provide evidence that combination antibiotic regimens effective in the treatment of invasive susceptible S pneumoniae pneumonia are equally effective in the treatment of invasive resistant (MIC = 2-4 microg/mL) and of intermediate (MIC = 0.1-1 microg/mL) S pneumoniae pneumonia.     

Comparison of bacteraemic community-acquired lobar pneumonia due to Streptococcus pneumoniae and Klebsiella pneumoniae in an intensive care unit.

In a study of 41 consecutive patients with bacteraemia-associated community-acquired lobar pneumonia due to Streptococcus pneumoniae and Klebsiella pneumoniae an attempt was made to determine whether distinguishing criteria of disease due to these organisms could be identified according to demographic features and the results of initial clinical and laboratory investigations. Such information would aid in the early initiation of appropriate antimicrobial therapy. The most significant difference between the two groups of patients was the lower platelet count in the K. pneumoniae group (p less than 0.005). In addition leucopenia (p less than 0.05), higher serum albumin (p less than 0.05), and the male sex (p less than 0.05) featured with an increased frequency in patients with pulmonary infection due to K. pneumoniae. Initial antimicrobial therapy in critically ill patients with community-acquired lobar pneumonia and thrombocytopenia, particularly when associated with leucopenia and in male patients, should include agents effective against K. pneumoniae.     

Influence of prior pneumococcal and influenza vaccination on outcomes of older adults with community-acquired pneumonia

OBJECTIVES: To determine whether prior pneumococcal and seasonal influenza vaccination improves outcomes in older adults hospitalized for community‐acquired pneumonia (CAP). DESIGN: Prospective, observational, multicenter study. SETTING: Five public hospitals providing universal free care to the whole population in three Spanish regions. PARTICIPANTS: Individuals aged 65 and older admitted to the hospital with CAP through the emergency department. MEASUREMENTS: Pneumococcal and influenza vaccination status. The primary study outcomes were intensive care unit (ICU) admission, length of hospital stay (LOS), and overall case‐fatality rate. Outcome variables of individuals vaccinated with both vaccines were compared with outcomes of those who were unvaccinated. RESULTS: Two hundred thirty‐eight individuals had received 23‐valent pneumococcal polysaccharide vaccine and seasonal influenza vaccination and were compared with 195 unvaccinated individuals. No differences were found with respect to combined antibiotic therapy between groups (38.0% vs 39.7%; P=.80). Similar percentages of vaccinated and unvaccinated individuals required ICU admission (7.2% vs 8.2%; P=.69). Mean LOS was significantly shorter in vaccinated individuals (9.9 vs 12.4 days; P=.04). Overall case‐fatality rates were similar in both groups (5.9% vs 5.1%; P=.73). After adjustment, LOS, risk of ICU admission, and overall case‐fatality rate were not associated with prior pneumococcal and seasonal influenza vaccination. CONCLUSION: The clinical outcomes of vaccinated older adults hospitalized with CAP were not better than those observed in unvaccinated individuals.     

Chlamydia pneumoniae infections in patients with community-acquired pneumonia in Slovenia

It is well known that Chlamydia pneumoniae is an important respiratory pathogen. In this study, the prevalence of specific antibodies to C. pneumoniae in hospitalized patients with community-acquired pneumonia (943 adult females, 990 adult males and 185 children) was evaluated over a period of 7 y (1993-99). Two serum samples were obtained from all of the patients: 1 on admission and the other 3 weeks later. The specimens were tested for C. pneumoniae IgG, IgM and IgA antibodies by means of a microimmunofluorescence test. Acute infection with C. pneumoniae was determined in 9.4% of females and 13.1% of males. In children and adolescent patients, the microimmunofluorescence test showed recent infection in 8.6% of cases, with the highest prevalence occurring in the 11-15 y age group. The highest prevalence of C. pneumoniae pneumonia was found in 1995 and 1999: 15.4% and 13.6% respectively. The results obtained showed that C. pneumoniae is persistently present in the population of Slovenia.