Viral and Mycoplasma pneumoniae community-acquired pneumonia and novel clinical outcome evaluation in ambulatory adult patients in China

External validation of a new predictive model for falls among inpatients using the official Japanese ADL scale, Bedriddenness ranks: a double-centered prospective cohort study

Background

Several reliable predictive models for falls have been reported, but are too complicated and time-consuming to evaluate. We recently developed a new predictive model using just eight easily-available parameters including the official Japanese activities of daily living scale, Bedriddenness ranks, from the Ministry of Health, Labour and Welfare. This model has not yet been prospectively validated. This study aims to prospectively validate our new predictive model for falls among inpatients admitted to two different hospitals.

Methods

A double-centered prospective cohort study was performed from October 1, 2018, to September 30, 2019 in an acute care hospital and a chronic care hospital. We analyzed data from all adult inpatients, for whom all data required by the predictive model were evaluated and recorded. The eight items required by the predictive model were age, gender, emergency admission, department of admission, use of hypnotic medications, previous falls, independence of eating, and Bedriddenness ranks. The main outcome is in-hospital falls among adult inpatients, and the model was assessed by area under the curve.

Results

A total of 3,551 adult participants were available, who experienced 125 falls (3.5%). The median age (interquartile range) was 78 (66–87) years, 1,701 (47.9%) were men, and the incidence of falls was 2.25 per 1,000 patient-days and 2.06 per 1,000 occupied bed days. The area under the curve of the model was 0.793 (95% confidence interval: 0.761–0.825). The cutoff value was set as − 2.18, making the specificity 90% with the positive predictive value and negative predictive value at 11.4% and 97%.

Conclusions

This double-centered prospective cohort external validation study showed that the new predictive model had excellent validity for falls among inpatients. This reliable and easy-to-use model is therefore recommended for prediction of falls among inpatients, to improve preventive interventions.

Trial registration

UMIN000040103 (2020/04/08)

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02871-5.

Prediction of risk factors of bronchial mucus plugs in children with Mycoplasma pneumoniae pneumonia

Background

Recently, many cases of pneumonia in children with Mycoplasma pneumoniae infection have been shown to have varying degrees of intrabronchial mucus plug formation. The clinical, laboratory, radiological characteristics, and treatment of patients with Mycoplasma infection are analyzed in this study. The risk factors for M. pneumoniae pneumonia (MPP) mucus plug formation in children are explored, and a risk factor scoring system is established.

Methods

MPP patients treated with bronchoscopy were retrospectively enrolled in the study from February 2015 to December 2019. The children were divided into a mucus plug group and a control group according to the presence or absence of mucus plug formation. The clinical, laboratory, radiological characteristics, and treatment of the two groups of children were compared. Univariate and multivariate logistic regression models were used to identify the risk factors for MPP mucus plug formation. The receiver operating characteristic (ROC) curve was drawn to evaluate the regression model and establish the MPP mucous plug risk factor scoring system.

Results

A univariate analysis showed that the children in the mucous group were older and had a longer fever duration, longer hospital stay, higher fever peak, more cases of wheezing symptoms and allergies, and azithromycin or corticosteroids were administered later. In addition, neutrophil, C-reactive protein (CRP), lactate dehydrogenase (LDH), D-dimer (DD), sputum MP-DNA copy number, and total immunoglobulin A (IgA) levels were higher, while prealbumin (PA) levels were lower. The ROC curve analysis showed that children with MPP had PA ≤144.5 mg/L, had used corticosteroids during the course of the illness of ≥4.5 days, CRP ≥12.27 mg/L, an LDH ≥ 462.65 U/L, and there was a possibility of intra-airway mucus formation. The independent risk factors were scored according to their odds ratio (OR) value. Among the 255 children with MPP, the high-risk group had 44 (83.02%) mucus plugs out of 53; the middle-risk group had 35 (34.3%) mucus plugs out of 102; and the low-risk group had 11 (11%) mucus plugs out of 100.

Conclusions

PA levels, timing of corticosteroid use (use in the first few days), CRP levels, and LDH levels were independent risk factors for MPP mucus plug formation. This provides a basis for the early identification of MPP in children combined with mucus plug formation.

Antibodies against atypical pathogens and respiratory viruses detected by Pneumoslide IgM test in adults with community-acquired pneumonia in Guangzhou City

Background

To detect the serum antibodies against respiratory viruses and atypical pathogens in adults with community‐acquired pneumonia (CAP) in Guangzhou City (Guangdong province, China).

Methods

A retrospective study was carried out with samples from 685 adults who were admitted with CAP and 108 non‐CAP control patients. Atypical pathogens and respiratory viruses in serum were detected using the Pneumoslide IgM test from Vircell, Spain. All patients were divided into 6 groups according to age: 18‐24, 25‐44, 45‐59, 60‐74, 75‐89, and >90.

Results

The total positive rate of CAP was 35.4%, which was highest in the 18‐24 age group (P < .05). The highest positive rate, 17.11%, was observed for Mycoplasma pneumoniae (MP). The mean age of MP‐infected patients was higher than that of the controls (P < .05). The positive rates for influenza B (INFB), Legionella pneumophila (LP1), Coxiella burnetii (COX), influenza A (INFA), parainfluenza virus (PIV), respiratory syncytial virus (RSV), Chlamydophila pneumoniae (CP), and adenovirus (ADV) were 5.56%, 3.07%, 2.63%, 2.34%, 1.90%, 1.61, 0.88%, and 0.29%, respectively. There were 4.37% of patients with CAP having multiple infections. The main symptoms observed in the 685 CAP patients were cough and sputum production, in 78.4% and 67.4%. Fever was followed by 54% of CAP patients. Dyspnea (39.1%), anorexia (36.8%), increased thirst (26.7%), chills (18.7), headache (14.6%), and nausea (13.1%) were also frequently observed in the CAP patients.

Conclusions

MP infection was the most common in adult CAP patients in Guangzhou City with the highest positive rate in the 18‐24 age groups.

Analysis of antibiotic usage for viral community-acquired pneumonia in adults

The rationale for the antibiotic treatment of viral community-acquired pneumonia (CAP) in adults was analyzed to develop a clinical reference standard for this condition. Clinical data from 166 patients diagnosed with viral pneumonia across 14 hospitals in Beijing from November 2010 to December 2017 were collected. The indications for medications were evaluated, and the rationale for the use of antibiotics was analyzed. A total of 163 (98.3%) patients with viral pneumonia were treated with antibiotics. A combination of C-reactive protein (CRP) and procalcitonin (PCT) was used as markers to analyze the possible indications for antibiotic use. With threshold levels set at 0.25 µg/L for PCT and 20 mg/L for CRP, the rate of unreasonable use of antibiotics was 55.2%. By contrast, at a CRP level threshold of 60 mg/L, the rate of antibiotic misuse was 77.3%. A total of 39 of the 163 (23.9%) patients did not meet the guidelines for drug selection for viral CAP in adults. The unreasonable use of antibacterial drugs for the treatment of viral CAP in adults is a serious concern. Clinicians must reduce the unnecessary use of antibiotics.

Early diagnosis and appropriate respiratory support for Mycoplasma pneumoniae pneumonia associated acute respiratory distress syndrome in young and adult patients: a case series from two centers

BACKGROUND

Mycoplasma pneumoniae (M. pneumoniae) is one of the most common causes of community acquired pneumonia (CAP). Establishing an early diagnosis of M. pneumoniae pneumonia in patients with acute respiratory distress syndrome (ARDS) may have important therapeutic implications.

METHODS

We describe diagnosis and management of M. pneumoniae pneumonia induced ARDS in a case series of adults and youth hospitalized with radiographically confirmed CAP prospectively enrolled in an observational cohort study in two university teaching hospitals, from November 2017 to October 2019.

RESULTS

In all 10 patients, early and rapid diagnosis for severe M. pneumoniae pneumonia with ARDS was achieved with polymerase chain reaction (PCR) or metagenomic next-generation sequencing (mNGS) testing of samples from the lower respiratory tract or pleural effusion. The average PaO₂/FiO₂ of all patients was 180 mmHg. Of the 10 cases, 4 cases had moderate ARDS (100 mmHg ≤ PaO₂/FiO₂ < 200 mmHg) and 3 cases had severe ARDS (PaO₂/FiO₂ < 100 mmHg). High flow nasal cannula (HFNC) was applied in all patients, though only two patients were sufficiently supported with HFNC. Invasive mechanical ventilation (IMV) was required in 5 patients. High resistance (median 15 L/cmH₂O/s) and low compliance (median 38 ml/cmH₂O) was observed in 4 cases. In these 4 cases, recruitment maneuvers (RM) were applied, with 1 patient demonstrating no response to RM. Prone positioning were applied in 4 cases. Two cases needed ECMO support with median support duration of 5.5 days. No patient in our case series received corticosteroid therapy. All patients were survived and were discharged from hospital.

CONCLUSIONS

Early and rapid diagnosis of severe M. pneumoniae pneumonia with ARDS can be achieved with PCR/mNGS tests in samples from the lower respiratory tract or pleural effusion. In our case series, half of M. pneumoniae pneumonia induced ARDS cases were adequately supported with HFNC or NIV, while half of cases required intubation. RM and prone position were effective in 30% of intubated cases, and 20% needed ECMO support. When early anti-mycoplasmal antibiotics were given together with sufficient respiratory support, the survival rate was high with no need for corticosteroid use.

Burden of Community-Acquired Pneumonia and Unmet Clinical Needs

Community-acquired pneumonia (CAP) is the leading cause of death among infectious diseases and an important health problem, having considerable implications for healthcare systems worldwide. Despite important advances in prevention through vaccines, new rapid diagnostic tests and antibiotics, CAP management still has significant drawbacks. Mortality remains very high in severely ill patients presenting with respiratory failure or shock but is also high in the elderly. Even after a CAP episode, higher risk of death remains during a long period, a risk mainly driven by inflammation and patient-related co-morbidities. CAP microbiology has been altered by new molecular diagnostic tests that have turned viruses into the most identified pathogens, notwithstanding uncertainties about the specific role of each virus in CAP pathogenesis. Pneumococcal vaccines also impacted CAP etiology and thus had changed Streptococcus pneumoniae circulating serotypes. Pathogens from specific regions should also be kept in mind when treating CAP. New antibiotics for CAP treatment were not tested in severely ill patients and focused on multidrug-resistant pathogens that are unrelated to CAP, limiting their general use and indications for intensive care unit (ICU) patients. Similarly, CAP management could be personalized through the use of adjunctive therapies that showed outcome improvements in particular patient groups. Although pneumococcal vaccination was only convincingly shown to reduce invasive pneumococcal disease, with a less significant effect in pneumococcal CAP, it remains the best therapeutic intervention to prevent bacterial CAP. Further research in CAP is needed to reduce its population impact and improve individual outcomes.

Mycoplasma pneumoniae infection mimicking tuberculous pleurisy in a young woman: a case report and literature review

A 30-year-old woman was admitted to a different hospital with a 2-day history of fever, cough, and expectoration. She had a history of left pulmonary tuberculosis 8 years previously. Chest computed tomography showed an infiltrate in the inferior lobe of the left lung and spot-like calcifications in the anterior lobe of the upper left lobe and lower lobe of the left lung. After antibacterial treatment, the patient’s condition deteriorated and she developed significant pleural effusion on the left side. The pleural effusion assay showed a lymphocyte-predominant exudate with a significantly increased adenosine deaminase level. The patient was transferred to our hospital with a suspected diagnosis of tuberculous pleuritis. A serum test for Mycoplasma pneumoniae-specific immunoglobulin M was positive. Because of the limitations of this test in determining the occurrence of recent infection, a thoracoscopic pleural biopsy was performed, and M. pneumoniae DNA was detected in the biopsy tissue using M. pneumoniae-specific polymerase chain reaction. Thus, the patient was diagnosed with M. pneumoniae-related parapneumonic effusion. Clinicians must be aware of the usefulness and limitations of a high adenosine deaminase level and know that lymphocyte predominance in pleural effusion does not always indicate tuberculous pleurisy, especially in areas of high tuberculosis prevalence.

Diagnostic value of quantitative MP-IgG for Mycoplasma pneumoniae pneumonia in adults

The passive particle agglutination (PA) test, once widely used for Mycoplasma pneumoniae (M. pneumoniae) antibody detection, has gradually been replaced by quantitative enzyme-linked immunosorbent assays (ELISA). However, the lack of diagnostic criteria for quantitative ELISA M. pneumoniae-IgG (MP-IgG) and the low positive rates of ELISA M. pneumoniae-IgM (MP-IgM) limit the diagnostic value of ELISA for M. pneumoniae infection in adults. Here, the diagnostic value of quantitative ELISA MP-IgG was evaluated in adults with Mycoplasma pneumoniae pneumonia (MPP). The serum M. pneumoniae antibodies were detected in 162 patients with MPP, 228 patients with community-acquired pneumonia (CAP) with non-Mycoplasma pneumoniae (NMP), and 162 healthy controls by ELISA, using the PA results as the reference standards. For the MP-IgM-/IgG+ subgroup, a single serum MP-IgG level of ≥92.67 RU/mL can be used as a reference criterion for the diagnosis of acute M. pneumoniae infection. At admission, for patients with CAP, the sensitivity and specificity of ELISA MP-IgM positivity for MPP were 18.51% and 99.56%, respectively. MP-IgM positivity combined with MP-IgG ≥ 92.67 RU/mL increased the sensitivity to 40.12% and decreased the specificity to 94.29%. For paired serum samples obtained within seven days, an ELISA MP-IgG concentration change of ≥1.48-fold and MP-IgG ≥ 92.67 RU/mL on day 7 were used as the diagnostic criteria for M. pneumoniae infection. Accordingly, the combination of qualitative MP-IgM detection and quantitative MP-IgG detection by ELISA is valuable for acute MPP diagnosis in adults.

Outbreak of mycoplasmal round pneumonia in an adult population: A case series

BACKGROUND

Mycoplasmal pneumonia is a common type of adult community-acquired pneumonia in China, but round/spherical pneumonia caused by mycoplasma pneumoniae has rarely been reported. Here, we report an outbreak of mycoplasmal round pneumonia in a military dormitory in China.

METHODS

We analysed epidemiological, clinical, imaging and laboratory data from a series of adults affected by an outbreak of mycoplasmal round pneumonia in the dormitory of a military hospital (Fuzhou General Hospital) in Fuzhou, China. The dormitory included 2 separate buildings. Mycoplasma antibody was detected using a passive agglutination assay.

RESULTS

The first case in our series, a 23-year-old male intern, presented on July 16, 2015 with a 3-day history of low-grade fever, dizziness, fatigue and chest tightness. Chest computed tomography revealed spherical masses. Over the following 4 days, 11 individuals who had been in close contact with the first patient were found to have similar masses. All 12 cases were mildly symptomatic or asymptomatic, and fever was the only sign visible upon physical examination. Chest radiology revealed single, round consolidations in 3 cases and multiple round consolidations in 9 cases; consolidations ranged in size from 0.2 to 2.9 cm. Most cases had normal blood cell count, erythrocyte sedimentation rate and C reactive protein level. Nasopharyngeal swabs from all cases tested negative for 25 pathogens, including Mycoplasma pneumoniae, in a PCR-based assay performed on August 1, 2015. All 12 patients showed a 4-fold increase in the titre of anti-mycoplasmal pneumonia antibody in paired sera on August 13, 2015. Patients were given the antibiotic moxifloxacin or symptomatic treatment, and 11 of the 12 cases showed complete resolution of round pneumonia lesions within 4 weeks.

CONCLUSION

This case series illustrates the diversity of clinical manifestations as well as imaging findings for mycoplasmal pneumonia, to which clinicians should pay more attention. Mycoplasmal round pneumonia should be included in differential diagnosis of multiple pulmonary nodules in adults in order to enable accurate clinical identification of disease and successful treatment and resolution.

Disease severity and clinical outcomes of community-acquired pneumonia caused by non-influenza respiratory viruses in adults: a multicentre prospective registry study from the CAP-China Network

Although broad knowledge of influenza viral pneumonia has been established, the significance of non-influenza respiratory viruses in community-acquired pneumonia (CAP) and their impact on clinical outcomes remains unclear, especially in the non-immunocompromised adult population.Hospitalised immunocompetent patients with CAP were prospectively recruited from 34 hospitals in mainland China. Respiratory viruses were detected by molecular methods. Comparisons were conducted between influenza and non-influenza viral infection groups.In total, 915 out of 2336 adult patients with viral infection were enrolled in the analysis, with influenza virus (28.4%) the most frequently detected virus, followed by respiratory syncytial virus (3.6%), adenovirus (3.3%), human coronavirus (3.0%), parainfluenza virus (2.2%), human rhinovirus (1.8%) and human metapneumovirus (1.5%). Non-influenza viral infections accounted for 27.4% of viral pneumonia. Consolidation was more frequently observed in patients with adenovirus infection. The occurrence of complications such as sepsis (40.1% versus 39.6%; p=0.890) and hypoxaemia (40.1% versus 37.2%; p=0.449) during hospitalisation in the influenza viral infection group did not differ from that of the non-influenza viral infection group. Compared with influenza virus infection, the multivariable adjusted odds ratios of CURB-65 (confusion, urea >7 mmol·L^-1, respiratory rate ≥30 breaths·min^-1, blood pressure <90 mmHg (systolic) or ≤60 mmHg (diastolic), age ≥65 years) ≥3, arterial oxygen tension/inspiratory oxygen fraction <200 mmHg, and occurrence of sepsis and hypoxaemia for non-influenza respiratory virus infection were 0.87 (95% CI 0.26-2.84), 0.72 (95% CI 0.26-1.98), 1.00 (95% CI 0.63-1.58) and 1.05 (95% CI 0.66-1.65), respectively. The hazard ratio of 90-day mortality was 0.51 (95% CI 0.13-1.91).The high incidence of complications in non-influenza viral pneumonia and similar impact of non-influenza respiratory viruses relative to influenza virus on disease severity and outcomes suggest more attention should be given to CAP caused by non-influenza respiratory viruses.

Diagnosis of mycoplasma pneumoniae by loop-mediated isothermal amplification: systematic review and meta-analysis

Background

A novel method, termed loop-mediated isothermal amplification (LAMP), was developed by Notomi et al. (2000). Individually published results have been reported that this technology has been successfully applied to the detection of a variety of pathogens. However, the overall diagnostic accuracy of LAMP for Mycoplasma pneumoniae (MP) remains unclear. A meta-analysis was therefore performed to review the accuracy of LAMP for Mycoplasma pneumoniae.

Methods

Cochrane Library and PubMed were systematically searched and checked for studies using LAMP for detecting mycoplasma pneumoniae. We used PCR as a reference standard to evaluate the quality of the studies eligible for inclusion in the meta-analysis. Then, the data from the studies were extracted by two independent assessors. Meta-DiSc 1.4 software was utilized to test the heterogeneity of sensitivity (SEN), specificity (SP), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnosis odds ratio (DOR). The pooled analysis results were plotted, and the summary receiver operating characteristic (SROC) curve was plotted by calculating the area under the curve (AUC). Generated pooled summary estimates (95% CIs) were calculated for the overall accuracy, and a bivariate meta-regression model was used for the meta-analysis.

Results

Seven studies with nine fourfold tables were included in this meta-analysis. The pooled SEN and SPE for diagnosing Mycoplasma pneumoniae were 0.90 (95% CI: 0.87–0.93) and 0.98 (95% CI: 0.96–0.99), respectively. The PLR was 31.25 (95% CI: 14.83–65.87), NLR 0.10 (95% CI: 0.05–0.22), DOR 399.32 (95% CI: 172.01–927.00), and AUC 0.9892.

Conclusions

In conclusion, compared with PCR, LAMP is a valuable alternative method for Mycoplasma pneumoniae diagnosis in clinic with high sensitivity and specificity. However, more evidence is required to confirm that LAMP can fully replace other methods in the clinical diagnosis of MP.

Effects of a clinical pathway on antibiotic use in patients with community-acquired pneumonia: a multi-site study in China

BACKGROUND

Community-acquired pneumonia (CAP) is a common condition with high mortality, morbidity and healthcare costs. This study aimed to determine whether clinical pathway (CP) implementation in different hospitals in China increased antibiotic compliance with the national CP in inpatients with CAP.

METHODS

Chart reviews of CAP cases were conducted in 18 public hospitals from 3 different regions of China in 2015. Chi-square tests and the t-test were used to compare differences between hospitals that implemented CP (CP group) and those that did not (non-CP group). Multivariate logistic analysis was adopted to test whether CP implementation for CAP in hospitals affected their overall antibiotic use compliance rates with the national CP for CAP.

RESULTS

The overall compliance rate with the national CP for inpatients with CAP was 43.69%. The compliance rates for timely initial antibiotic use, recommended antibiotic use and use of the recommended combination of antibiotics and the overall compliance rate were substantially higher in the CP group than in the non-CP group. A multivariate logistic model for overall compliance in inpatients with CAP showed that the hospitals in the CP group had greater overall compliance than those in the non-CP group (odds ratio [OR] = 1.76; 95% confidence interval [CI] = 1.16-2.71) after controlling for hospital and inpatient characteristics.

CONCLUSION

In China, the overall compliance rate with the national CP for inpatients with CAP was low, but inpatients with CAP in the hospitals in the CP group received antibiotics more concordantly with the national CP. Since adherence to evidence-based care has been shown to improve clinical outcomes, internal and external support from hospitals is required to facilitate CP implementation for inpatients with CAP. Additionally, governmental commitment, hospital input and population involvement are required to improve antibiotic utilization.

Contemporary Situation of Community-acquired Pneumonia in China: A Systematic Review

The prevalence and microbial pattern reported for Community-acquired pneumonia (CAP) differ considerably and contemporary situation remains changing over time. We therefore searched both international and domestic databases for relevant references and pooled incidence of CAP and etiological distribution were estimated separately between children and adults groups. The results showed that CAP remained a major public health issue in China, with a relatively higher incidence than that reported in Western countries. Although pathogens were not detected in nearly half of patients, Mycoplasma pneumoniae remained to be the most frequently detected agent across age groups, the detection yield of which was lower than that reported from other countries. Notably, the incidence of influenza virus A in adults was almost four times higher than that in children while the prevalence of respiratory syncytial virus was much less common in adults than that in children. Despite some limitations, the value of this review, approaching to systematically review grey published data, is to sketch out the contemporary epidemiological and etiological situation of CAP in our country, which could be useful to help policymakers and clinicians make informed choices and to inspire future studies and surveillance.

Comparison of viral infection in healthcare-associated pneumonia (HCAP) and community-acquired pneumonia (CAP)

Background

Although viruses are known to be the second most common etiological factor in community-acquired pneumonia (CAP), the respiratory viral profile of the patients with healthcare-associated pneumonia (HCAP) has not yet been elucidated. We investigated the prevalence and the clinical impact of respiratory virus infection in adult patients with HCAP.

Methods

Patients admitted with HCAP or CAP, between January and December 2016, to a tertiary referral hospital in Korea, were prospectively enrolled, and virus identification was performed using reverse-transcription polymerase chain reaction (RT-PCR).

Results

Among 452 enrolled patients (224 with HCAP, 228 with CAP), samples for respiratory viruses were collected from sputum or endotracheal aspirate in 430 (95.1%) patients and from nasopharyngeal specimens in 22 (4.9%) patients. Eighty-seven (19.2%) patients had a viral infection, and the proportion of those with viral infection was significantly lower in the HCAP than in the CAP group (13.8% vs 24.6%, p = 0.004). In both the HCAP and CAP groups, influenza A was the most common respiratory virus, followed by entero-rhinovirus. The seasonal distributions of respiratory viruses were also similar in both groups. In the HCAP group, the viral infection resulted in a similar length of hospital stay and in-hospital mortality as viral–bacterial coinfection and bacterial infection, and the CAP group showed similar results.

Conclusions

The prevalence of viral infection in patients with HCAP was lower than that in patients with CAP, and resulted in a similar prognosis as viral–bacterial coinfection or bacterial infection.

MERS, SARS and other coronaviruses as causes of pneumonia

Human coronaviruses (HCoVs) have been considered to be relatively harmless respiratory pathogens in the past. However, after the outbreak of the severe acute respiratory syndrome (SARS) and emergence of the Middle East respiratory syndrome (MERS), HCoVs have received worldwide attention as important pathogens in respiratory tract infection. This review focuses on the epidemiology, pathogenesis and clinical characteristics among SARS-coronaviruses (CoV), MERS-CoV and other HCoV infections.

Diagnosis and treatment of community-acquired pneumonia in adults: 2016 clinical practice guidelines by the Chinese Thoracic Society, Chinese Medical Association

Community‐acquired pneumonia (CAP) in adults is an infectious disease with high morbidity in China and the rest of the world. With the changing pattern in the etiological profile of CAP and advances in medical techniques in diagnosis and treatment over time, Chinese Thoracic Society of Chinese Medical Association updated its CAP guideline in 2016 to address the standard management of CAP in Chinese adults. Extensive and comprehensive literature search was made to collect the data and evidence for experts to review and evaluate the level of evidence. Corresponding recommendations are provided appropriately based on the level of evidence. This updated guideline covers comprehensive topics on CAP, including aetiology, antimicrobial resistance profile, diagnosis, empirical and targeted treatments, adjunctive and supportive therapies, as well as prophylaxis. The recommendations may help clinicians manage CAP patients more effectively and efficiently. CAP in pediatric patients and immunocompromised adults is beyond the scope of this guideline. This guideline is only applicable for the immunocompetent CAP patients aged 18 years and older. The recommendations on selection of antimicrobial agents and the dosing regimens are not mandatory. The clinicians are recommended to prescribe and adjust antimicrobial therapies primarily based on their local etiological profile and results of susceptibility testing, with reference to this guideline.

Mycoplasma pneumoniae from the Respiratory Tract and Beyond

Mycoplasma pneumoniae is an important cause of respiratory tract infections in children as well as adults that can range in severity from mild to life-threatening. Over the past several years there has been much new information published concerning infections caused by this organism. New molecular-based tests for M. pneumoniae detection are now commercially available in the United States, and advances in molecular typing systems have enhanced understanding of the epidemiology of infections. More strains have had their entire genome sequences published, providing additional insights into pathogenic mechanisms. Clinically significant acquired macrolide resistance has emerged worldwide and is now complicating treatment. In vitro susceptibility testing methods have been standardized, and several new drugs that may be effective against this organism are undergoing development. This review focuses on the many new developments that have occurred over the past several years that enhance our understanding of this microbe, which is among the smallest bacterial pathogens but one of great clinical importance.

Viral infection in community-acquired pneumonia: a systematic review and meta-analysis

The advent of PCR has improved the identification of viruses in patients with community-acquired pneumonia (CAP). Several studies have used PCR to establish the importance of viruses in the aetiology of CAP.We performed a systematic review and meta-analysis of the studies that reported the proportion of viral infection detected via PCR in patients with CAP. We excluded studies with paediatric populations. The primary outcome was the proportion of patients with viral infection. The secondary outcome was short-term mortality.Our review included 31 studies. Most obtained PCR via nasopharyngeal or oropharyngeal swab. The pooled proportion of patients with viral infection was 24.5% (95% CI 21.5-27.5%). In studies that obtained lower respiratory samples in >50% of patients, the proportion was 44.2% (95% CI 35.1-53.3%). The odds of death were higher in patients with dual bacterial and viral infection (OR 2.1, 95% CI 1.32-3.31).Viral infection is present in a high proportion of patients with CAP. The true proportion of viral infection is probably underestimated because of negative test results from nasopharyngeal or oropharyngeal swab PCR. There is increased mortality in patients with dual bacterial and viral infection.

Sustained Viremia and High Viral Load in Respiratory Tract Secretions Are Predictors for Death in Immunocompetent Adults with Adenovirus Pneumonia

The predictors for fatal adenovirus (AdV) pneumonia among immunocompetent adults are unclear. Laboratory-confirmed, hospitalized AdV pneumonia adults were prospectively enrolled in Beijing Chao-Yang hospital from March to June 2013. Clinical data and serial whole blood and respiratory tract secretions from such patients were collected. Quantitative real-time polymerase chain reaction was performed to quantify the viral load. A total of 14 AdV pneumonia cases were consecutively enrolled, and four of them were fatal. Ten cases were caused by AdV-55, three by AdV-7 and one by AdV-3. There were no differences in age, gender or underlying diseases between the patients in the fatal cases and surviving cases. At admission (on day 5-7 after illness onset), the patients in fatal cases presented higher initial viral loads in respiratory tract secretions (8.578 ± 2.115 vs 6.263 ± 1.225 Log10 copies/ml, p = 0.023). All patients in fatal cases presented with viremia on day 12-14 (100% vs 66.7%, p = 0.017). A higher initial viral load in the respiratory tract and sustained viremia (more than 2 weeks) may be predictors for fatal clinical outcomes.

Emergency treatment and nursing of children with severe pneumonia complicated by heart failure and respiratory failure: 10 case reports

Pneumonia refers to lung inflammation caused by different pathogens or other factors, and is a common pediatric disease occurring in infants and young children. It is closely related to the anatomical and physiological characteristics of infants and young children and is more frequent during winter and spring, or sudden changes in temperature. Pneumonia is a serious disease that poses a threat to children's health and its morbidity and mortality rank first, accounting for 24.5-65.2% of pediatric inpatients. Due to juvenile age, severe illness and rapid changes, children often suffer acute heart failure, respiratory failure and even toxic encephalopathy at the same time. The concurrence in different stages of the process of emergency treatment tends to relapse, which directly places the lives of these children at risk. Severe pneumonia constitutes one of the main causes of infant mortality. In the process of nursing children with severe pneumonia, intensive care was provided, including condition assessment and diagnosis, close observation of disease, keeping the airway unblocked, rational oxygen therapy, prevention and treatment of respiratory and circulatory failure, support of vital organs, complications, and health education. The inflammatory response was proactively controlled, to prevent suffocation and reduce mortality. In summary, positive and effective nursing can promote the rehabilitation of children patients, which can be reinforced with adequate communication with the parents and/or caretakers.

Clinical data analysis of 19 cases of community-acquired adenovirus pneumonia in immunocompetent adults

The aim of this study was to investigate the characteristics of clinical manifestations, laboratory tests and imaging changes of community-acquired adenovirus pneumonia in immunocompetent adults. A retrospective study was performed on 19 adult community-acquired adenovirus pneumonia cases in Yantai, whereby the clinical data were collected and analyzed. Of 19 cases, 14 (73.68%) had fever and 17 (89.47%) had cough symptoms. Moreover, 14 cases (73.68%) had normal white blood cell counts, while 11 cases (57.89%) exhibited a reduction in lymphocyte proportion. Among the 19 cases, 17 cases exhibited lesions in a single lung, while 2 cases involved bilateral lungs. The lesions predominantly exhibited ground glass-like changes. The clinical manifestations of adult community-acquired adenovirus pneumonia patients with normal immune functions were mild, with such presenting symptoms as fever, cough, and sputum; most patients did not exhibit high levels of white blood cells or low lymphocyte counts, and the imaging features (ground glass-like effusion) were indicative of single-lung involvement.

A case of methylprednisolone treatment for interstitial pneumonia induced by gefitinibin

In this case, an old man was diagnosed as lung cancer, clinical stage IV. In order to alleviate cancer, this patient was treated with gefitinib. Three months later, symptoms such as a significant weakness, chest tightness and shortness of breath after sports arised and intensifying. Implosive therapy with high dose methylprednisolone is used to control the weakness caused by gefitinib. Eight days after treatment, patient's condition significantly improved. The use of methylprednisolone can effectively treat interstitial pneumonia induced by gefitinibin, help patients get better from critical condition such as type I respiratory failure. This new discovery is a good guidance for clinical treatment of gefitinibin caused interstitial pneumonia.

Incidence of respiratory viral infections detected by PCR and real-time PCR in adult patients with community-acquired pneumonia: a meta-analysis

Background

With the development of more rapid and sensitive detection methods based on PCR techniques, the contributions of respiratory viral infections to community-acquired pneumonia (CAP) in adult patients are being more and more recognized. Yet, up to now, there has been a lack of synthetic data that clearly demonstrates the incidence of respiratory viral infections in adult patients with CAP.

Objectives

We intended to demonstrate the incidence of respiratory viral infections detected by PCR and real-time PCR in adult patients with CAP.

Methods

We searched PubMed and Embase for studies providing the incidence of respiratory viral infections in adult patients with CAP. We investigated potential sources of heterogeneity by a univariant metaregression analysis and calculated the combined incidence of viral infections, viral infections mixed with other pathogens and individual respiratory virus species.

Results

We eventually identified 23 eligible reports with a total number of 6,404 patients. Incidences ranged from 8.6 to 56.2% for overall respiratory viral infections. We noted significant heterogeneity in incidence estimates for the incidence of viral infections (Cochran's χ² = 269.9, p < 0.0001, I² = 91.8%). The combined incidence of viral infections was 22.4% (95% CI = 19.0-25.7). Incidences of viral coinfections with other pathogens ranged from 3 to 28%. A high level of heterogeneity was identified as well during the estimates for incidences of coinfections (χ² = 200.9, p < 0.0001, I² = 91.5%). The combined incidence of viral coinfections with other pathogens was 12.4% (95% CI = 9.7-15.0). Our heterogeneity analyses suggested that a lower respiratory tract sample was associated with higher overall viral incidence. Moreover, the influenza virus, rhinovirus and coronavirus were the 3 most frequently detected viral pathogens in adult patients with CAP according to our study.

Conclusions

Respiratory viruses are probably crucial pathogens of adult patients with CAP, with the influenza virus being the most frequent viral pathogen identified. More than half of the viral infections are characterized as mixed infections with other pathogens.

Viral etiology of community-acquired pneumonia among adolescents and adults with mild or moderate severity and its relation to age and severity

BACKGROUND

Better knowledge of distribution of respiratory viruses (RVs) in adolescents and adults with community-acquired pneumonia (CAP) is needed.

METHODS

To investigate the RVs etiology among adolescents and adults with CAP, according to age and pneumonia severity index (PSI), a multi-center, prospective study was conducted from November 2010 to April 2012. Fifteen RVs were tested by polymerase chain reaction (PCR). Bacteria were detected by urinary antigen, conventional culture and PCR.

RESULTS

Mean (SD) age and median (IQR) PSI score of 954 patients enrolled was 45.2 (19.5) years (range 14-94) and 42 (36). RVs were found in 262 patients (27.5%): influenza virus A (IFV A, 9.9%) comprised of pandemic H1N1 (6.7%) and seasonal H3N2 (3.5%), human rhinovirus (4.3%), adenovirus (4.2%), human metapneumovirus (1.8%), parainfluenza virus 1, 3 and 2 (1.7%, 1.5% and 1.2%). Influenza virus B, enterovirus, respiratory syncytial virus, human coronavirus and parainfluenza virus 4 were rarely detected (<1%). Frequency of IFV A was highest among patients aged between 45-64 years (p < 0.001), while adenovirus among patients aged 14-17 years (p < 0.001), no differences was found in other RVs. The proportion of pandemic H1N1 increased with severity of pneumonia evaluated by PSI (P < 0.05).

CONCLUSIONS

The proportion of RVs in CAP is higher than previously reported. IFV A pneumonia are usually found in patients older than 45 years, while, adenovirus pneumonia are common in adolescents and young adults. Pandemic H1N1 virus is still recognized by PSI as a high-severity pathogen. The findings contribute baseline data on viral CAP study in China.

Associations of radiological features in Mycoplasma pneumoniae pneumonia

INTRODUCTION

The associations of radiological features with clinical and laboratory findings in Mycoplasma pneumoniae infection are poorly understood. The purpose of this study was to assess the associations.

MATERIAL AND METHODS

A retrospective cohort study of 1230 patients with community-acquired pneumonia was carried out between January 2005 and December 2009. The diagnosis of M. pneumoniae infection was made using the indirect microparticle agglutinin assay and enzyme-linked immunosorbent assay.

RESULTS

Females were more susceptible to M. pneumoniae infection. Ground-glass opacification on radiographs was positively associated with M. pneumoniae-IgM titres (rank correlation coefficient (r s) = 0.141, p = 0.006). The left upper lobe was more susceptible to infection with M. pneumoniae compared with other pathogens. More increases in the risk of multilobar opacities were found among older or male patients with M. pneumoniae pneumonia (odds ratio, 1.065, 3.279; 95% confidence interval, 1.041-1.089, 1.812-5.934; p < 0.001, p < 0.001; respectively). Patients with M. pneumoniae pneumonia showing multilobar opacities or consolidation had a significantly longer hospital length of stay (r s = 0.111, r s = 0.275; p = 0.033, p < 0.001; respectively), incurring significantly higher costs (r s = 0.119, r s = 0.200; p = 0.022, p < 0.001; respectively).

CONCLUSIONS

Our study highlighted female susceptibility to M. pneumoniae pneumonia and the association of ground-glass opacification with higher M. pneumoniae-IgM titres. The left upper lobe might be more susceptible to M. pneumoniae infection. Older or male patients with M. pneumoniae pneumonia were more likely to show multilobar opacities. Multilobar opacities and consolidation were positively associated with hospital length of stay and costs.

The bacterial aetiology of adult community-acquired pneumonia in Asia: a systematic review

BACKGROUND

Community-acquired pneumonia (CAP) is a major cause of adult mortality in Asia. Appropriate empirical treatment depends on knowledge of the pathogens commonly responsible. However, assessing the aetiological significance of identified organisms is often difficult, particularly with sputum isolates that might represent contamination with oropharyngeal flora.

METHODS

A systematic review of all adult CAP aetiology studies from Asia, excluding the Middle East, published in English between 1 January 1990 and 1 March 2012 was conducted. Forty-eight studies reporting on 10 423 patients were included, representing data from China, India, Indonesia, Japan, Malaysia, The Philippines, Singapore, South Korea, Taiwan, Thailand and Vietnam. Data from large parts of Asia were unavailable and there was substantial heterogeneity in methodology.

RESULTS

As in western studies, Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella spp. and Haemophilus influenzae were all significant pathogens. However, compared with western studies, S. pneumoniae was of less relative importance. Gram-negative bacilli and Mycobacterium tuberculosis were more important, and in northeast Thailand Burkholderia pseudomallei was a major pathogen.

CONCLUSION

These data have major implications for diagnostic strategies and empirical treatment. Narrow-spectrum antibiotics targeting S. pneumoniae may be inappropriate in many Asian settings, and agents active against TB may lead to partial response and delayed TB diagnosis.

Emergence of community-acquired adenovirus type 55 as a cause of community-onset pneumonia

BACKGROUND

Since 2008, severe cases of emerging human adenovirus (HAdV) type 55 (HAdV-55) were reported sporadically in China. But no comparative studies had been conducted to discern the differences in epidemiologic and clinical abnormalities between HAdV-55 and other types (HAdV-7, HAdV-3, HAdV-14, HAdV-50, and HAdV-C).

METHODS

A multicenter surveillance study for adult and adolescent community-acquired pneumonia (CAP) was conducted prospectively in Beijing and Yan Tai between November 2010 and April 2012. A standardized data form was used to record clinical information. The viral DNA extracted from the clinical samples or adenovirus viral isolates was sequenced.

RESULTS

Among 969 cases, 48 (5%) were identified as adenovirus pneumonia. Six branches were clustered: HAdV-55 in 21, HAdV-7 in 11, HAdV-3 in nine, HAdV-14 in four, HAdV-50 in two, and HAdV-C in one. Most HAdV-55 cases were identified during February and March. All the hypervariable regions of the hexon genes of the 21 HAdV-55 strains were completely identical. Patients who had HAdV-55 were about 10 years older ( P = .027) and had higher pneumonia severity index scores ( P = .030) compared with those with other types (HAdV-7, HAdV-3, HAdV-14, HAdV-50, and HAdV-C). Systemic BP was also higher among patients in the HAdV-55 group ( P = .006). Unilateral or bilateral consolidations were the most common radiologic findings in both patients with HAdV-55 and those with other types (57.9% vs 36%). More than one-half of the patients were admitted to hospital; oxygen therapy was given to 29.2% of the 48 patients, and two needed mechanical ventilation.

CONCLUSIONS

HAdV-55 has established itself as a major pneumonia pathogen in the Chinese population, and further surveillance and monitoring of this agent as a cause of CAP is warranted.

Molecular identification of adenoviruses associated with respiratory infection in Egypt from 2003 to 2010

Background

Human adenoviruses of species B, C, and E (HAdV-B, –C, -E) are frequent causative agents of acute respiratory infections worldwide. As part of a surveillance program aimed at identifying the etiology of influenza-like illness (ILI) in Egypt, we characterized 105 adenovirus isolates from clinical samples collected between 2003 and 2010.

Methods

Identification of the isolates as HAdV was accomplished by an immunofluorescence assay (IFA) and confirmed by a set of species and type specific polymerase chain reactions (PCR).

Results

Of the 105 isolates, 42% were identified as belonging to HAdV-B, 60% as HAdV–C, and 1% as HAdV-E. We identified a total of six co-infections by PCR, of which five were HAdV-B/HAdV-C co-infections, and one was a co-infection of two HAdV-C types: HAdV-5/HAdV-6. Molecular typing by PCR enabled the identification of eight genotypes of human adenoviruses; HAdV-3 (n = 22), HAdV-7 (n = 14), HAdV-11 (n = 8), HAdV-1 (n = 22), HAdV-2 (20), HAdV-5 (n = 15), HAdV-6 (n = 3) and HAdV-4 (n = 1). The most abundant species in the characterized collection of isolates was HAdV-C, which is concordant with existing data for worldwide epidemiology of HAdV respiratory infections.

Conclusions

We identified three species, HAdV-B, -C and -E, among patients with ILI over the course of 7 years in Egypt, with at least eight diverse types circulating.

Etiological analysis and predictive diagnostic model building of community-acquired pneumonia in adult outpatients in Beijing, China

BACKGROUND

Etiological epidemiology and diagnosis are important issues in adult community-acquired pneumonia (CAP), and identifying pathogens based on patient clinical features is especially a challenge. CAP-associated main pathogens in adults include viruses as well as bacteria. However, large-scale epidemiological investigations of adult viral CAP in China are still lacking. In this study, we analyzed the etiology of adult CAP in Beijing, China and constructed diagnostic models based on combinations of patient clinical factors.

METHODS

A multicenter cohort was established with 500 adult CAP outpatients enrolled in Beijing between November 2010 to October 2011. Multiplex and quantitative real-time fluorescence PCR were used to detect 15 respiratory viruses and mycoplasma pneumoniae, respectively. Bacteria were detected with culture and enzyme immunoassay of the Streptococcus pneumoniae urinary antigen. Univariate analysis, multivariate analysis, discriminatory analysis and Receiver Operating Characteristic (ROC) curves were used to build predictive models for etiological diagnosis of adult CAP.

RESULTS

Pathogens were detected in 54.2% (271/500) of study patients. Viruses accounted for 36.4% (182/500), mycoplasma pneumoniae for 18.0% (90/500) and bacteria for 14.4% (72/500) of the cases. In 182 of the patients with viruses, 219 virus strains were detected, including 166 single and 53 mixed viral infections. Influenza A virus represented the greatest proportion with 42.0% (92/219) and 9.1% (20/219) in single and mixed viral infections, respectively. Factors selected for the predictive etiological diagnostic model of viral CAP included cough, dyspnea, absence of chest pain and white blood cell count (4.0-10.0) × 10(9)/L, and those of mycoplasma pneumoniae CAP were being younger than 45 years old and the absence of a coexisting disease. However, these models showed low accuracy levels for etiological diagnosis (areas under ROC curve for virus and mycoplasma pneumoniae were both 0.61, P < 0.05).

CONCLUSIONS

Greater consideration should be given to viral and mycoplasma pneumoniae infections in adult CAP outpatients. While predictive etiological diagnostic models of viral and mycoplasma pneumoniae based on combinations of demographic and clinical factors may provide indications of etiology, diagnostic confirmation of CAP remains dependent on laboratory pathogen test results.

Viral aetiology in adults with acute upper respiratory tract infection in Jinan, Northern China

Our study investigated the epidemiology of respiratory viruses in adult patients with upper respiratory tract infection (URTI) between August 2009 and September 2010 in Jinan, northern China. Nasal and throat swabs (n = 596) were collected from adult patients with URTIs. Nine respiratory-related viruses, including IFV, PIV, HRV, HMPV, HBoV, HCoV, ADV, RSV, and EV, were detected in all samples by conventional and reverse transcription polymerase chain reactions. Positive detection rate for respiratory virus was 38.76% and codetection rate was 4.70% in adults with acute respiratory tract infections. IFV (20.81%) was the dominant agent detected and IFVB had a higher incidence (12.58%) than IFVA (7.72%). Detection rates of 8.22%, 5.03%, 3.69%, and 2.52% were observed for HBoV, HRV, EV, and RSV, respectively. HCoV had the lowest detection rate of 0.50%. HBoV, HRV, EV, and ADV infection rates were higher in the 14-25-year-old group than in the 26-65-year-old group. Codetection rates were higher (7.52%) in the 14-25-year-old group than in the older age group (2.64%). The spectrum of respiratory virus infection in adult patients with URTIs was different in Jinan compared with other cities in China.

Accuracy of IgM antibody testing, FQ-PCR and culture in laboratory diagnosis of acute infection by Mycoplasma pneumoniae in adults and adolescents with community-acquired pneumonia

Background

Diagnosis of community-acquired pneumonia (CAP) caused by Mycoplasma pneumoniae in adults and adolescents is hampered by a lack of rapid and standardized tests for detection.

Methods

CAP patients from 12 teaching hospitals were prospectively and consecutively recruited. Basic and clinical information, throat swabs and paired sera were collected. Mycoplasma pneumoniae was detected by IgG and IgM antibody tests, fluorescence quantitative polymerase chain reaction (FQ-PCR) and culture. A comparative study of the diagnostic values of three methods, including sensitivity, specificity, positive and negative predictive values and positive likelihood ratio (PLR) was conducted. A fourfold or greater increase of IgG antibody titers of paired sera was set as the diagnostic “gold standard”.

Results

One hundred and twenty-five CAP patients (52.8% males, median age 47 years, range 14–85) were enrolled. Twenty-seven (21.6%) patients were diagnosed with acute Mycoplasma pneumoniae infections by the “gold standard”. Specificity values of all three methods were around 90%. An increasing trend of sensitivity, positive predictive value and PLR was found, with the lowest in IgM testing (7.4%, 28.6% and 1.45), intermediate in FQ-PCR (40.7%, 50% and 3.63), and highest in culture (55.6%, 75% and 10.9).

Conclusions

In the defined group of patients, there was a good agreement between positive rate of MP cultivation of throat swabs and acute M. pneumoniae infection (PLR of 10.9). Since the sensitivity is low in all of the evaluated methods, the logical approach would be to incorporate PCR, culture and serological tests for optimum diagnosis of acute Mycoplasma pneumoniae infections in adults and adolescents.

Regional epidemiology of invasive pneumococcal disease in Asian adults: epidemiology, disease burden, serotype distribution, and antimicrobial resistance patterns and prevention

OBJECTIVES

To summarize published data on the clinical and economic burden, epidemiology, antimicrobial resistance levels, serotype prevalence, and prevention strategies for pneumococcal disease among adults in Asia.

METHODS

We performed a systematic search of the PubMed database for relevant, peer-reviewed articles published between January 1995 and December 2011, covering China, Hong Kong, India, Indonesia, Japan, Malaysia, Pakistan, the Philippines, Singapore, South Korea, Taiwan, Thailand, and Vietnam.

RESULTS

Taiwan and Thailand had the most comprehensive epidemiological data on adult pneumococcal disease. Very little relevant data were found for Indonesia, Pakistan, the Philippines, and Vietnam; surveillance is urgently needed in these countries. The emergence and spread of resistance emphasize the importance of vaccination to prevent infection in adults at increased risk for serious pneumococcal disease. Vaccination policies and opinions on the efficacy of vaccination vary widely in Asian countries, although a new option in the form of a pneumococcal conjugate vaccine is now available.

CONCLUSIONS

Increased awareness of the public health and economic benefits of pneumococcal vaccination is critically needed to help both the public and policymakers in making changes to vaccination policies in the region. Maximizing access to pneumococcal vaccines will decrease the number of hospitalizations, complications, and deaths associated with pneumococcal disease.

Detection and serotyping of human adenoviruses from patients with influenza-like illness in mongolia

Human adenoviruses (HAdVs) are responsible for approximately 5%-10% of acute respiratory infections. The serotypes of commonly detected respiratory HAdV in Asian countries are diverse. However, there are no well-documented reports of circulating HAdV serotypes in Mongolia. Between January 2010 and May 2011, 1,950 influenza-negative samples from patients with influenza-like illness, including eye swabs from patients with eye symptoms, were screened for HAdV, and 40 samples (2.1%) were positive for HAdVs. Among these 40 samples, 31 samples were positive for the hexon gene used in phylogenetic analysis, as determined by PCR. We identified 7 different serotypes. We constructed the phylogenetic trees of HAdV-B7 and HAdV-B3, the 2 most commonly detected serotypes in this study. All detected HAdV-B7 and -B3 Mongolian strains had identical sequences. HAdV-D8, known to be associated with epidemic keratoconjunctivitis (EKC), was detected from nasopharyngeal and eye swabs. There was no difference between the amino acid sequences of the hexon and fiber genes that may affect tissue tropism in Mongolian strains and those in EKC-causing strains.

Severe community-acquired pneumonia caused by adenovirus type 11 in immunocompetent adults in Beijing

BACKGROUND

Severe community-acquired pneumonia (CAP) due to human adenoviruses (HAdVs) in immunocompetent adults has raised concerns.

OBJECTIVE

To describe the clinical, laboratorial, and radiological characteristics of adenovirus pneumonia and detect the type and diversity of human adenoviruses that caused acute respiratory distress syndrome (ARDS) in Beijing.

STUDY DESIGN

An etiological study of adult community-acquired pneumonia was carried out prospectively at Beijing Chao-Yang Hospital. A total of 18 cases with laboratory-confirmed adenovirus infections in 487 cases with CAP were observed clinically. The viral type and phylogenetic analysis were tested by polymerase chain reaction (PCR).

RESULTS

Patients with adenovirus pneumonia typically reported flu-like symptoms. Some of them developed shortness of breath or severe dyspnea on 6 days after disease onset. The patients with ARDS usually present dyspnea, higher level of serum muscle enzymes and bilateral, mutilobal consolidation and patchy/ground-glass opacities. HAdVs type was detected in 17 samples and all of them belonged to species B (HAdV-11, 7, 3 and 14). Among them, HAdV-11 was most frequently (10/17), followed by HAdV-7 (5/17). Phylogenetic analysis of the partial penton nucleotide confirmed a close relationship with stains circulating in the Beijing region.

CONCLUSIONS

Our identification of severe respiratory illness due to adenovirus, especially type 11 may highlight the need for rapid diagnosis and improved surveillance, which may assist with targeted development of antiviral agents or type-specific vaccines.