Clinical features and etiology of patients with community-acquired pneumonia in southern China

doi:10.21203/rs.3.rs-34710/v1

PDF

Research article

Clinical features and etiology of patients with community-acquired pneumonia in southern China

https://doi.org/10.21203/rs.3.rs-34710/v1

This work is licensed under a CC BY 4.0 License

Version 1

posted 12 Jun, 2020

You are reading this latest preprint version

Background: The aim of this study was to investigate the clinical features and etiology in patients with community-acquired pneumonia (CAP) in southern China. Methods: A total of 342 patients who presented community-acquired pneumonia (CAP) from January 2019 to December 2019 were enrolled in this study. The respiratory pathogens in nine test and loop-mediated isothermal amplification (LAMP) detection were used to identify pathogens.

Results: The mean age of this study population was 60.89 ± 18.87 years. The total incidences of CAP were more prevalent in males (60.5%, 207/342) than females (39.5%, 135/342), and the percentage was 65.8% (225/342) CAP patients in summer and autumn. The main causative pathogens were identified in 96/342 (28.1 %) patients. Of these, 14 (14.6 %) were MP infection, the most frequently isolated microorganism. Bacterial infection in the single infection was present in 47 (47/96, 49.0%). Mixed infections were demonstrated in 26 (26/96, 27.1%). MRSA infection was close to patients with systemic diseases (P = 0.001). Factors that were associated with systemic disease was the age >65 (OR 5.555, 95%CI 3.402-9.071, P<0.001).

Conclusions: MP is common organisms isolated in community-acquired pneumonia. The year of above 65, the count of WBC and mixed pathogens infections may be associated with an increased risk of CAP patients with systemic disease.

Infectious Diseases

CAP

pathogens

infection

Community-acquired pneumonia (CAP) is a common clinical disease that ranked as the fifth leading cause of mortality global[1]. It is reported that there are about 3.2 million people die from CAP each year globally, surpassing other infectious diseases, such as tuberculosis, HIV and malaria[2]. A prospective multicenter study in Asia reported that the mortality rate of CAP in Asia was as high as 7.3%[3]. Several factors are associated with the risk of CAP mortality, including inflammatory response, cardiovascular complications, and etiology[4–6]. Some studies identified age and male sex increases the incidence of CAP[7, 8]. Identification the etiology of CAP patients remains challenging, 30–65% of patients do not have a certain pathogen isolated[9]. Streptococcus pneumoniae(S. pneumoniae) is the most frequently identified CAP pathogen[10]. The etiology of a large number of CAP patients is triggered by bacterial and viral microorganisms, 20–50% of CAP cases are cause by bacterial pathogens[11, 12]. Viral CAP pathogens such as Influenza, respiratory syncytial virus are the most common[13]. CAP also has impact on national economic development for high consumption rates of therapy in both inpatient and outpatient. CAP patients have not been sufficiently evaluated, leading to almost all patients are treated empirically because of the lack of specifics diagnostic methods to rapidly isolate the pathogen[14].

The bacterial culture and smear microscopy are the detection of bacterial pathogen most extensively used[15]. In recent years, loop-mediated isothermal amplification (LAMP) have become a useful alternative to the effective detection of pathogenic micorganism. LAMP-based PCR is detection of thirteen common respiratory pathogens in patients with CAP[16, 17].

Microbial cause varies by host factors and geographic location. The aim of this study is to analysize the pathogens and clinical features of patients that were diagnosed of CAP in southern China.

Study patients

342 hospitalized patients with CAP were recruited from inpatient of Meizhou People’s Hospital between January 2019 to December 2019. All participants age from 13 to 99 years old in this study. Patients were diagnosed as CAP if they met one of the following clinical characteristics: (1) typical characteristics of pneumonia, which were defined by a new infiltrate on a chest X-rays or computed tomography (CT) scan examined by radiologists. (2) one or more respiratory symptoms, including new cough, exacerbated cough with or without sputum production, fever (> 37.8 °C) or hypothermia (< 35.6 °C)[18].

The study was approved by the ethics committee of Meizhou people’s hospital and all participants signed an informed consent form. Severe immunodepression (severe hematological disease, HIV infection), use of immunosuppressive medications were excluded. The data of CAP patients of the clinical and laboratory testing were collected, analyzed, and compared.

Microbiological diagnostic method

Two sensitivity analyses were performed, including nucleic acid detection of respiratory pathogenic bacteria in loop-mediated isothermal amplification (LAMP)-based and respiratory pathogens in nine test were chosen for pathogens identification of viruses, atypical microorganisms and bacteria. Respiratory pathogens in nine test : the serum of patients with extraction for its detection, respectively, Adenovirus, Q therricus, Chlamydia pneumonia, Influenza B virus, Legionella pneumophila, Influenza A virus, Mycoplasma pneumonia, Parainfluenza virus, Respiratory syncytial virus were tested by indirect immunofluorescent assay. Loop-mediated isothermal amplification (LAMP): all sputum samples were performed by using the Universal Kit for Bacterial DNA Extraction Kit (CapitalBio, Chengdu, China) according to the manufacturer’s recommended protocol for DNA extraction and examined by PCR for respectively detection of Acinetobacter baumannii(A. baumannii), Methicillin-resistant staphylococcus(MRSA), Streptococcus pneumoniae(S.pneumoniae), Staphylococcus aureus(S.aureus), Escherichia coli(E.coli), Klebsiella pneumoniae(K. pneumoniae), Pseudomonas aeruginosa(P. aeruginosa), Stenotrophomonas maltophilia(S. maltophilia), Haemophilus influenzae(H. influenzae), Legionella pneumophila(L. pneumophila), Mycoplasma pneumoniae(MP), Chlamydia pneumonia(CP), Mycobacterium tuberculosis complex(MTBC). PCR procedure: 37 °C for 3 minutes and 65 °C for 47 minutes. Detection of amplified products by viewing the real-time imaging system (CapitalBio Technology, Beijing, China) and pathogen nucleic acid detection software were used to analyze results.

Statistical analysis

SPSS 21.0 software(SPSS Inc., Chicago, USA) was used for statistical analyses of the data. Descriptive data are presented as frequencies (percentages). Categorical variables were compared with the Pearson Chi-square test. Two-group comparisons of continuous variables were compared with independent samples t-test. The level of statistically significant was P ≤ 0.05.

Study population and clinical characteristics

In Table 1, of the 342 patients with CAP, 207 patients (60.5%)were male and 135 patients (39.5%) were female. The average age of study population was 60.89, including 197 cases were nonelderly with a mean age of 48.38 (≤ 65 years), and 145 cases were elderly with a mean age of 77.90 (༞65 years). A total of 169 patients (49.42%) had at least 1 systemic diseases disease, including coronary artery disease, cerebral infarction, diabetes, hypertension. Laboratory parameters of the white blood cell (WBC) counts (> 9.5 × 10⁹ cells/L) was found in 145 cases (42.4%). Summer and autumn have more patients with CAP (108/342, 31.6%; 117/342, 34.2%) in this study.

Table 1

The clinical characteristics of the study population
Items	N (%)
Total	342
Gender
Male	207 (60.5)
Female	135 (39.5)
Age (years), mean ± SD	60.89 ± 18.87
≤ 65	197 (57.6)
༞65	145 (42.4)
Clinical symptom
Fever	171 (50)
Cough	311 (90.9)
Expectoration	279 (81.6)
Chest pain	19 (5.6)
Smoking	82 (24)
Drinking	57 (16.7)
WBC (> 9.5 × 10⁹ cells/L)	145 (42.4)
D-dimer (mean ± SD)	1.77 ± 1.48
Systemic diseases
Coronary artery disease	70 (20.5)
Cerebral infarction	45 (13.2)
Diabetes	46 (13.5)
Hypertension	89 (26)
Seasons
Spring (3–5)	43 (12.6)
Summer (6–8)	108 (31.6)
Autumn (9–11)	117 (34.2)
Winter (12 − 2)	74 (21.6)
SD: standard deviation, WBC: white blood cell

Pathogens

In 96/342 (28.1%) patients the etiology of CAP was identified. Pathogen detection showed that single infection was found in 70 patients (72.9%), the most frequently isolated microorganism was MP (14/96, 14.6%), followed by MRSA (12/96, 12.5%), fungus as a group (9/96, 9.4%), K. pneumonia (7/96, 7.3%), P. aeruginosa (6/96, 6.3%). Bacterial infection in the single infection was present in 47 (47/96, 49.0%). Mixed infections were demonstrated in 26 (26/96, 27.1%). Table 2 shows the number of every causal microorganisms.

Table 2

The etiological analysis of identified in patients with CAP
Pathogen	Cases (%)
Single infection
P. aeruginosa	6 (6.3)
S. maltophilia	1 (1.0)
L. pneumophila	2 (2.1)
A. baumannii	3 (3.1)
E. coli	4 (4.2)
K. pneumoniae	7 (7.3)
S. pneumoniae	3 (3.1)
MTBC	4 (4.2)
S. aureus	3 (3.1)
H. influenzae	4 (4.2)
MRSA	12 (12.5)
Fungus	9 (9.4)
MP	14 (14.6)
Multiple pathogens
MP + Flu B	1 (1.0)
MP + Flu B + E. coli	1 (1.0)
MP + S. aureus	1 (1.0)
MP + MRSA + K. pneumoniae	1 (1.0)
MP + K. pneumonia + A. baumannii	1 (1.0)
MRSA + E. coli + A. baumannii	1 (1.0)
MRSA + S. maltophilia + L. pneumophila	1 (1.0)
S. aureus + MRSA + P. aeruginosa	1 (1.0)
Adenovirus + S. aureus + MRSA + P. aeruginosa + A. baumannii	1 (1.0)
MRSA + P. aeruginosa	2 (2.1)
MRSA + L. pneumophila	1 (1.0)
MRSA + MTBC	1 (1.0)
MRSA + K. pneumoniae	1 (1.0)
MRSA + E. coli	1 (1.0)
H. influenzae + L. pneumophila	1 (1.0)
S. aureus + MRSA	1 (1.0)
Adenovirus + S. aureus + MRSA	1 (1.0)
S. pneumoniae + P. aeruginosa	1 (1.0)
S. pneumoniae + MRSA	1 (1.0)
K. pneumoniae + A. baumannii	1 (1.0)
E. coli + H. influenzae	1 (1.0)
E. coli + K. pneumoniae	1 (1.0)
E. coli + A. baumannii	1 (1.0)
Total	96
P. aeruginosa: Pseudomonas aeruginosa, S. maltophilia: Stenotrophomonas maltophilia, L. pneumophila: Legionella pneumophila, A. baumannii: Acinetobacter baumannii, E. coli: Escherichia coli, K. pneumonia: Klebsiella pneumonia, S. pneumoniae : Streptococcus pneumonia, MTBC: Mycobacterium tuberculosis complex, S. aureus: Staphylococcus aureus, H. influenza: Haemophilus influenza, MRSA: Methicillin-resistant staphylococcus, MP: Mycoplasma pneumonia, Flu B: Influenza B virus, Flu A: Influenza A virus

Microbial Etiology According To Systemic Diseases

We divided all patients into two groups according to the systemic diseases (shown in Table 3): systemic diseases group (169 cases), non-systemic diseases group (173 cases), MRSA infection was the most common in patients with systemic diseases (P = 0.001). MP infection in non-systemic diseases group was identified in 10 (52.63%) of the 19 patients, while there was no significant difference between systemic diseases group and non-systemic diseases group (P = 0.854). In addition, there were 9 cases with systemic diseases group infected by P. aeruginosa (P = 0.029).

Table 3

Effects of systemic disease on the distribution of 342 CAP pathogens
Pathogen	Systemic diseases N = 169	Non-systemic diseases N = 173	X²	P
MRSA	21	5	11.067	0.001
MP	9	10	0.034	0.854
K. pneumoniae	8	3	2.471	0.116
P. aeruginosa	9	2	4.774	0.029
E. coli	5	3	0.561	0.454
fungus	5	4	0.139	0.709
A. baumannii	4	3	0.171	0.679
S. aureus	6	2	2.145	0.143
MRSA: Methicillin-resistant staphylococcus, MP: Mycoplasma pneumonia, K. pneumonia: Klebsiella pneumonia, P. aeruginosa: Pseudomonas aeruginosa, E. coli: Escherichia coli, A. baumannii: Acinetobacter baumannii, S. aureus: Staphylococcus aureus

Microbial Etiology In Age Groups

We divided all patients into two groups according to the age (shown in Table 4): ≤65 years group (197 cases), ༞65 years group (145 cases). There was no significant difference that the two frequently detected pathogens were MRSA (P = 0.101) and MP (P = 0.614) between ≤ 65 years group and ༞65 years group. For CAP in patients above 65 years of age, 8 patients were caused by K. pneumoniae infection compared to ≤ 65 years, 3 patients had K. pneumoniae infection (P = 0.039). Microbial etiology by age group is shown in Table 4.

Table 4

Effect of age on the distribution of 342 CAP pathogens
Pathogen	≤ 65 y (N = 197)	༞65 y (N = 145)	X²	P
MRSA	11	15	2.695	0.101
MP	12	7	0.254	0.614
K. pneumoniae	3	8	4.281	0.039
P. aeruginosa	4	7	2.099	0.147
E. coli	4	4	0.194	0.660
fungus	3	6	2.229	0.135
A. baumannii	5	3	0.08	0.777
S. aureus	3	5	1.355	0.244
MRSA: Methicillin-resistant staphylococcus, MP: Mycoplasma pneumonia, K. pneumonia: Klebsiella pneumonia, P. aeruginosa: Pseudomonas aeruginosa, E. coli: Escherichia coli, A. baumannii: Acinetobacter baumannii, S. aureus: Staphylococcus aureus

Logistic Regression Analysis

In multivariable logistic regression analysis, > 65 years but not gender, was found to be significant risk factors for the patients with CAP associated with systemic disease (p < 0.001). Moreover, multiple pathogens and the counts of WBC were identified as independent risk factor for patients with CAP associated with systemic disease (OR 2.894, 95% CI 1.015–8.253, P = 0.047; OR 1.067, 95% CI 1.009–1.127, P = 0.022). No significant interaction was found between gender and smoking (P = 0.398, P = 0.654).Table 5 shows all ORs and 95% CIs.

Table 5

Multivariable logistic regression analysis of the patients with CAP associated with systemic disease
	OR	95% CI	P
Gender	1.265	0.734–2.179	0.398
> 65	5.555	3.402–9.071	< 0.001
Smoking	1.153	0.619–2.146	0.654
Multiple pathogens	2.894	1.015–8.253	0.047
WBC	1.067	1.009–1.127	0.022
WBC: white blood cell

CAP is a predominant threat to public health worldwide. In this study of 342 hospitalized CAP patients, 28.1% CAP cases were identified the etiology, lower than other regions is reported[9]. Maybe some patients included in this study were treated before go to the hospital. Furthermore, some patients may have received prior antibiotics that were consistent with the guidelines, but that failed. The potential bacterial may be obscured for patients use of antibiotics prior because of comorbidities[19]. Previous studies showed that etiology remains unknown in the most of cases, indicating that identification of a precise pathogen diagnosis for CAP patients is challenging[20].

The characteristics of CAP pathogens distribution in different regions are different, and with the passage of time, population distribution, seasonal alternation, the use of antibiotic and other factors, the anti-infection should be based on accurate diagnosis of pathogens, but due to the precise etiology testing has not been achieved in most patients, and there is currently no consistent antibiotic treatment plan[21]. In addition, alcoholism, smoking, chronic obstructive pulmonary disease (COPD), immunodeficiency, tumors, diabetes, cerebrovascular diseases and others have become risk factors of CAP, and the increase of age is closely related to the severity of CAP, which should be attached great importance to the prevention of CAP[22]. MP was the most frequently identified pathogens in our study. MP is a prokaryotic pleuropneumonia-like microorganism between bacteria and viruses that contains DNA and RNA and lacks the cell wall. Gram staining is negative, the diameter is 50–300 nm, the structure is simple, and it has various shapes such as sphere, rod, and filament that can pass through the bacteria filter. It is spread through close contact with infected patients with an incubation period of 1–3 weeks. It occurs more frequently in summer and autumn in the south, and more frequently in autumn and winter in the north. The prevalence of school-age children is 5–15 years old. It shows a downward trend after puberty and gradually disappears after adulthood. 25% of cases have extrapulmonary complications known as mucosal skin lesions[23].

MRSA was the most common bacterial etiology, followed by K. pneumoniae and P. aeruginosa in our identified cases. CAP caused by MRSA was the largest groups in our study group, with proportions of 11.5% and 15.6% in ≤ 65 years and ༞65 years, respectively. In addition, the percentages of bacterial pathogen infection with MRSA patients have systemic disease (21.9%) was relatively higher than patients without systemic disease group (P = 0.001). MRSA is the most common bacterial pathogen infection that gives rise to a high burden of significant healthcare costs, morbidity, and mortality for patients every year[24–26]. The percentages of bacterial pathogen infection with P. aeruginosa tested positive made up 9.4% among patients with systemic disease group (P = 0.029). We aimed to identify CAP patient characteristics associated with causative microorganisms in southern China. We found > 65, multiple pathogens and WBC are associated with a higher mortality rate; especially, above 65 years (OR 5.555, 95%CI 3.402–9.071, P < 0.001) was close associated with increased CAP patients with systemic disease mortality. Our study found that age was similar to the findings of previous studies[27–29].

There are some limitations deserve consideration in our study. One was that we did not investigate a larger sample size from the same population due to the data collection limited to one year. Second, we used only two different assays for different pathogens but did not clarify the differences in detection performance between these microbiological techniques. Third, some of the individuals in this population selfmedicated with antibiotics may not be generalized to CAPs. Therefore, further studies will be needed to confirm our findings.

MP is common organisms isolated in community-acquired pneumonia. The year of above 65, the count of WBC and mixed pathogens infections may be associated with an increased risk of CAP patients with systemic disease.

P. aeruginosa: Pseudomonas aeruginosa, S. maltophilia: Stenotrophomonas maltophilia, L. pneumophila: Legionella pneumophila, A. baumannii: Acinetobacter baumannii, E. coli: Escherichia coli, K. pneumonia: Klebsiella pneumonia, S. pneumoniae : Streptococcus pneumonia, MTBC: Mycobacterium tuberculosis complex, S. aureus: Staphylococcus aureus, H. influenza: Haemophilus influenza, MRSA: Methicillin-resistant staphylococcus, MP: Mycoplasma pneumonia, Flu B: Influenza B virus, Flu A: Influenza A virus, WBC: white blood cell, LAMP: loop-mediated isothermal amplification, OR: Odds ratio.

Ethics approval and consent to participate

The study was approved by the Ethics Committee of Meizhou People’s Hospital, Meizhou Academy of Medical Sciences, Meizhou Hospital Affiliated to Sun Yat-sen University (NO: MPH-HEC 2018-A-10). Written informed consent was obtained from each patient in the study and participants are children (under 16 years old) from their parents or legal guardians.

Acknowledgements

The author would like to thank other colleagues whom were not listed in the authorship and for their helpful comments on the manuscript of Research Experimental Center, Meizhou People’s Hospital (Huangtang Hospital), Meizhou Hospital Affiliated to Sun Yat-sen University.

Funding

This study was supported by Science and Technology Program of Meizhou (2019B0202001), Guangdong Provincial Key Laboratory of Precision Medicine and Clinical Translation Research of Hakka Population (2018B030322003), Key Scientific and Technological Project of Meizhou People’s Hospital (MPHKSTP-20180101). There was no role of the funding body in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript.

Availability of data and materials

The datasets generated during the current study are not publicly available yet, due to privacy concerns and ongoing additional research. Data can be made available for peer review on reasonable request through contacting the corresponding author.

Authors’ contributions

ZZ conceived and designed the experiments; SL recruited subjects and collected clinical data. CG conducted the laboratory testing. XG, RW, ZZ helped to analyze the data. CG wrote the manuscript. All authors read and approved the final manuscript.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Author details

1 Research Experimental Center, Meizhou People’s Hospital (Huangtang Hospital), Meizhou Academy of Medical Sciences, Meizhou Hospital Affiliated to Sun Yat-sen University, No 63 Huangtang Road, Meijiang District, Meizhou 514031, People’s Republic of China. 2 Guangdong Provincial Engineering and Technological Research Center for Molecular Diagnostics of Cardiovascular Diseases, No 63 Huangtang Road, Meijiang District, Meizhou 514031, People’s Republic of China. 3 Provincial Key Laboratory of Precision Medicine and Clinical Translational Research of Hakka Population, No 63 Huangtang Road, Meijiang District, Meizhou 514031, People’s Republic of China. 4 Center for Cardiovascular Diseases, Meizhou People’s Hospital (Huangtang Hospital), Meizhou Academy of Medical Sciences, Meizhou Hospital Affiliated to Sun Yat-sen University, Meizhou 514031, People’s Republic of China.

Niederman MS, Luna CM. Community-acquired pneumonia guidelines: a global perspective. Semin Respir Crit Care Med. 2012;33(3):298–310.
Lozano R, Naghavi M, Foreman K, Lim S, Shibuya K, Aboyans V, Abraham J, Adair T, Aggarwal R, Ahn SY, et al. Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet. 2012;380(9859):2095–128.
Song JH, Oh WS, Kang CI, Chung DR, Peck KR, Ko KS, Yeom JS, Kim CK, Kim SW, Chang HH, et al. Epidemiology and clinical outcomes of community-acquired pneumonia in adult patients in Asian countries: a prospective study by the Asian network for surveillance of resistant pathogens. Int J Antimicrob Agents. 2008;31(2):107–14.
Menendez R, Montull B, Reyes S, Amara-Elori I, Zalacain R, Capelastegui A, Aspa J, Borderias L, Martin-Villasclaras JJ, Bello S, et al. Pneumonia presenting with organ dysfunctions: Causative microorganisms, host factors and outcome. J Infect. 2016;73(5):419–26.
Corrales-Medina VF, Suh KN, Rose G, Chirinos JA, Doucette S, Cameron DW, Fergusson DA. Cardiac complications in patients with community-acquired pneumonia: a systematic review and meta-analysis of observational studies. PLoS Med. 2011;8(6):e1001048.
Yende S, D'Angelo G, Kellum JA, Weissfeld L, Fine J, Welch RD, Kong L, Carter M, Angus DC, Gen IMSI. Inflammatory markers at hospital discharge predict subsequent mortality after pneumonia and sepsis. Am J Respir Crit Care Med. 2008;177(11):1242–7.
Welte T, Kohnlein T. Global and local epidemiology of community-acquired pneumonia: the experience of the CAPNETZ Network. Semin Respir Crit Care Med. 2009;30(2):127–35.
Trotter CL, Stuart JM, George R, Miller E. Increasing hospital admissions for pneumonia, England. Emerg Infect Dis. 2008;14(5):727–33.
Remington LT, Sligl WI. Community-acquired pneumonia. Curr Opin Pulm Med. 2014;20(3):215–24.
Johansson N, Kalin M, Tiveljung-Lindell A, Giske CG, Hedlund J. Etiology of community-acquired pneumonia: increased microbiological yield with new diagnostic methods. Clinical infectious diseases: an official publication of the Infectious Diseases Society of America. 2010;50(2):202–9.
Luchsinger V, Ruiz M, Zunino E, Martinez MA, Machado C, Piedra PA, Fasce R, Ulloa MT, Fink MC, Lara P, et al. Community-acquired pneumonia in Chile: the clinical relevance in the detection of viruses and atypical bacteria. Thorax. 2013;68(11):1000–6.
Sangil A, Calbo E, Robles A, Benet S, Viladot ME, Pascual V, Cuchi E, Perez J, Barreiro B, Sanchez B, et al. Aetiology of community-acquired pneumonia among adults in an H1N1 pandemic year: the role of respiratory viruses. European journal of clinical microbiology infectious diseases: official publication of the European Society of Clinical Microbiology. 2012;31(10):2765–72.
Takahashi K, Suzuki M, Minh le N, Anh NH, Huong LT, Son TV, Long PT, Ai NT, Tho le H, Morimoto K, et al: The incidence and aetiology of hospitalised community-acquired pneumonia among Vietnamese adults: a prospective surveillance in Central Vietnam. BMC infectious diseases 2013, 13:296.
Lim WS, Macfarlane JT, Boswell TC, Harrison TG, Rose D, Leinonen M, Saikku P. Study of community acquired pneumonia aetiology (SCAPA) in adults admitted to hospital: implications for management guidelines. Thorax. 2001;56(4):296–301.
Mandell LA. Community-acquired pneumonia: An overview. Postgraduate medicine. 2015;127(6):607–15.
Fang X, Liu Y, Kong J, Jiang X. Loop-mediated isothermal amplification integrated on microfluidic chips for point-of-care quantitative detection of pathogens. Analytical chemistry. 2010;82(7):3002–6.
Parida M, Sannarangaiah S, Dash PK, Rao PV, Morita K. Loop mediated isothermal amplification (LAMP): a new generation of innovative gene amplification technique; perspectives in clinical diagnosis of infectious diseases. Rev Med Virol. 2008;18(6):407–21.
Halm EA, Teirstein AS. Clinical practice. Management of community-acquired pneumonia. N Engl J Med. 2002;347(25):2039–45.
Centers for Disease C, Prevention: Bacterial coinfections in lung tissue specimens from fatal cases of 2009 pandemic influenza A (H1N1) - United States, May-August 2009. MMWR Morbidity and mortality weekly report 2009, 58(38):1071–1074.
Jokinen C, Heiskanen L, Juvonen H, Kallinen S, Kleemola M, Koskela M, Leinonen M, Ronnberg PR, Saikku P, Sten M, et al. Microbial etiology of community-acquired pneumonia in the adult population of 4 municipalities in eastern Finland. Clinical infectious diseases: an official publication of the Infectious Diseases Society of America. 2001;32(8):1141–54.
Welte T, Torres A, Nathwani D. Clinical and economic burden of community-acquired pneumonia among adults in Europe. Thorax. 2012;67(1):71–9.
Polverino E, Torres Marti A. Community-acquired pneumonia. Minerva Anestesiol. 2011;77(2):196–211.
Zao I, Ribeiro F, Rocha V, Neto P, Matias C, Jesus G. Mycoplasma pneumoniae-associated Mucositis: A Recently Described Entity. European journal of case reports in internal medicine. 2018;5(11):000977.
Liu T, Zhang Y, Wan Q. Methicillin-resistant Staphylococcus aureus bacteremia among liver transplant recipients: epidemiology and associated risk factors for morbidity and mortality. Infection drug resistance. 2018;11:647–58.
Junie LM, Jeican II, Matros L, Pandrea SL. Molecular epidemiology of the community-associated methicillin-resistant staphylococcus aureus clones: a synthetic review. Clujul medical. 2018;91(1):7–11.
Hou J, Wu H, Zeng X, Rao H, Zhao P. Clinical evaluation of the loop-mediated isothermal amplification assay for the detection of common lower respiratory pathogens in patients with respiratory symptoms. Medicine. 2018;97(51):e13660.
Cilloniz C, Polverino E, Ewig S, Aliberti S, Gabarrus A, Menendez R, Mensa J, Blasi F, Torres A. Impact of age and comorbidity on cause and outcome in community-acquired pneumonia. Chest. 2013;144(3):999–1007.
Zalacain R, Torres A, Celis R, Blanquer J, Aspa J, Esteban L, Menendez R, Blanquer R, Borderias L. Pneumonia in the elderly working group AdTeIR: Community-acquired pneumonia in the elderly: Spanish multicentre study. Eur Respir J. 2003;21(2):294–302.
Riquelme R, Torres A, El-Ebiary M, de la Bellacasa JP, Estruch R, Mensa J, Fernandez-Sola J, Hernandez C, Rodriguez-Roisin R. Community-acquired pneumonia in the elderly: A multivariate analysis of risk and prognostic factors. Am J Respir Crit Care Med. 1996;154(5):1450–5.

PDF

Version 1

posted 12 Jun, 2020

You are reading this latest preprint version

Clinical features and etiology of patients with community-acquired pneumonia in southern China

Status:

Version 1

Abstract

Background

Methods

Study patients

Microbiological diagnostic method

Statistical analysis

Results

Study population and clinical characteristics

Pathogens

Microbial Etiology According To Systemic Diseases

Microbial Etiology In Age Groups

Logistic Regression Analysis

Discussion

Conclusions

Abbreviations

Declarations

References

Status:

Version 1