Prevalence and clinical significance of common respiratory pathogens in the upper respiratory tract of children with community-acquired pneumonia in Zunyi, China

The Epidemiologic and Clinical Features of Radiographic-Confirmed Community-Acquired Pneumonia Among Chinese Children: A Retrospective Hospital-Based Study

BACKGROUND

To help understand the disease burden of vaccine-preventable bacterial disease, we delineated the epidemiologic and clinical characteristics of radiographic-confirmed community-acquired pneumonia (CXR-CAP) among Chinese children.

METHODS

We retrospectively screened the electronic database of the hospital information system to identify all pediatric CAP cases admitted to the Children's Hospital of Soochow University between 2010 and 2014. Radiographic findings and clinical data were extracted from the medical charts through individual chart reviews. CXR-CAP cases were defined as the presence of consolidation or pleural effusion noted on chest radiograph reports. We employed a multivariate logistic regression model to identify the potential risk factors associated with CXR-CAP.

RESULTS

Among the 27,485 hospitalized CAP cases with radiologic data, 6322 (23.00%) were identified as CXR-CAP cases, while 21,163 (77.00%) were categorized as non-CXR-CAP cases. Children with CXR-CAP were notably older than those without CXR-CAP (non-CXR-CAP; χ2 = 1313.22; P < 0.01). CXR-CAP cases exhibited a higher rate of intensive care unit admission (3.55% vs. 1.94%; P < 0.01), extended hospital stays (73.87% vs. 63.79%; P < 0.01) and increased mortality rates (0.19% vs. 0.04%; P < 0.01). The factors associated with CXR-CAP included age (>12 months), season (summer and autumn), fever, abnormal breath sounds, C-reactive protein (>8 mg/L) and alanine transaminase (>40 U/L).

CONCLUSIONS

CXR-CAP cases consisted of a substantial proportion of hospitalized patients with CAP and had more severe clinical manifestations than in-patients without CXR-CAP among Chinese children.

Pediatric respiratory pathogen dynamics in Southern Sichuan, China: a retrospective analysis of gender, age, and seasonal trends

Objective

To address the research gap in the epidemiology of pediatric respiratory tract infections (RTIs) in Luzhou, Southern Sichuan, China, by analyzing respiratory pathogens in a large pediatric cohort from 2018 to 2021, covering the pre- and during-COVID-19 periods.

Methods

This study conducted a retrospective analysis of children with RTIs in Luzhou from July 2018 to January 2021. Strict exclusion criteria were applied to ensure an accurate representation of the pediatric population. Pathogen detection included viruses, bacteria, and atypical agents.

Results

Pathogens were identified in 52.8% of 12,546 cases. Viruses accounted for 32.2% of infections, bacteria for 29.8%, and atypical agents for 29.7%, with significant findings of Staphylococcus aureus, Moraxella catarrhalis, and Mycoplasma pneumoniae. Age-related analysis indicated a higher incidence of bacterial infections in infants and viral infections in preschool-aged children, with atypical pathogens being most prevalent in 3-5-year-olds. Gender-based analysis, adjusted for age, revealed similar overall pathogen presence; however, females were more susceptible to viral infections, while males were more prone to Streptococcus pneumoniae. Notably, there was an unusual increase in pathogen cases during spring, potentially influenced by behavioral changes and public health measures related to COVID-19. Co-infections were identified as a significant risk factor for the development of pneumonia.

Conclusion

The study provides essential insights into the epidemiology of respiratory pathogens in pediatric populations, emphasizing the need for healthcare strategies tailored to age, gender, and seasonality. The findings highlight the impact of environmental and public health factors, including COVID-19 measures, on respiratory pathogen prevalence, underscoring the importance of targeted diagnostic and treatment protocols in pediatric respiratory infections.

Impact of the COVID-19 pandemic on Haemophilus influenzae infections in pediatric patients hospitalized with community acquired pneumonia

The COVID-19 pandemic has altered the infection landscape for many pathogens. This retrospective study aimed to compare Haemophilus influenzae (H. influenzae) infections in pediatric CAP patients hospitalized before (2018-2019) and during (2020-2022) the COVID-19 pandemic. We analyzed the clinical epidemiology and antimicrobial resistance (AMR) patterns of H. influenzae from a tertiary hospital in southwest China. A total of 986 pediatric CAP patients with H. influenzae-associated infections were included. Compared to 2018, the positivity rate increased in 2019 but dropped significantly in 2020. Although it rose in the following 2 years, the rate in 2022 remained significantly lower than in 2019. Patients' age during the pandemic was significantly higher than in 2018 and 2019, while gender composition remained similar across both periods. Notably, there were significant changes in co-infections with several respiratory pathogens during the pandemic. Resistance rates of H. influenzae isolates to antibiotics varied, with the highest resistance observed for ampicillin (85.9%) and the lowest for cefotaxime (0.0%). Resistance profiles to various antibiotics underwent dramatic changes during the COVID-19 pandemic. Resistance to amoxicillin-clavulanate, cefaclor, cefuroxime, trimethoprim-sulfamethoxazole, and the proportion of multi-drug resistant (MDR) isolates significantly decreased. Additionally, MDR isolates, alongside isolates resistant to specific drugs, were notably prevalent in ampicillin-resistant and β-lactamase-positive isolates. The number of pediatric CAP patients, H. influenzae infections, and isolates resistant to certain antibiotics exhibited seasonal patterns, peaking in the winter of 2018 and 2019. During the COVID-19 pandemic, sharp decreases were observed in February 2020, and there was no resurgence in December 2022. These findings indicate that the COVID-19 pandemic has significantly altered the infection spectrum of H. influenzae in pediatric CAP patients, as evidenced by shifts in positivity rate, demographic characteristics, respiratory co-infections, AMR patterns, and seasonal trends.

Effect of Antimicrobial Stewardship 2018 on severe pneumonia with bacterial infection in paediatric intensive care units

OBJECTIVES

Antimicrobial Stewardship 2018 (ASP 18) in China emphasizes the hierarchical control of antimicrobial drugs and the management of physicians' prescribing authority, especially in children. The purpose of this study was to assess the effect of implementation of ASP 2018 on antibiotic consumption, resistance, and treatment outcomes in children with severe pneumonia from bacterial infections.

METHODS

A single center, retrospective study was conducted on 287 children with severe bacterial pneumonia, including 165 patients before intervention (May 2016-April 2018) and 122 patients after intervention (May 2018-April 2020). The antimicrobial resistance rates, antibiotic consumption, and clinical outcomes of the two periods were compared.

RESULTS

After the implementation of ASP 2018, Staphylococcus aureus (17.9%) became the predominant Gram-positive bacterium. The resistance of Streptococcus pneumoniae to clindamycin, erythromycin, and tetracycline was significantly reduced (P < 0.001), and Staphylococcus aureus to tetracycline also decreased (P = 0.034). In addition, Klebsiella pneumoniae (18.4%) replaced Pseudomonas aeruginosa (9.5%) as the most common Gram-negative bacterium. The resistance rates of Klebsiella pneumoniae to amoxicillin/clavulanic acid (AMC) and trimethoprim/sulfamethoxazole (SXT), and Acinetobacter baumannii to cefotaxime and SXT decreased significantly (P < 0.02). Total consumption (DDD/100 patient-days) of five antibiotics (cephalosporins, carbapenems, macrolides, antifungal agents, and linezolid) showed a decreasing trend, and the decrease in antifungal agents and linezolid was the most significant (27.4% and 25.6%, P < 0.001). The isolation rate of multidrug-resistant (MDR) strains decreased significantly from the highest, 16.8%, before intervention to 6.7% after intervention (P < 0.001).

CONCLUSION

Our data indicate that the implementation of antimicrobial management strategies has significantly reduced the consumption of antibiotics and the occurrence of antimicrobial resistance in children with severe bacterial pneumonia in PICU.

The Contribution of Viruses and Bacteria to Childhood Community-acquired Pneumonia: 11-Year Observational Study From Norway

BACKGROUND

Viruses are associated with pediatric community-acquired pneumonia (CAP) but are also common in the upper airways of healthy children. We have determined the contribution of respiratory viruses and bacteria by comparing children with CAP and hospital controls.

METHODS

Children less than 16 years old with radiologically confirmed CAP (n = 715) were enrolled over an 11-year period. Children admitted for elective surgery during the same period served as controls (n = 673). Nasopharyngeal aspirates were tested for 20 respiratory pathogens by semiquantitative polymerase chain reaction tests and cultivated for bacteria and viruses. We used logistic regression to calculate adjusted odds ratios [aOR; 95% confidence intervals (CIs)], and estimated population-attributable fractions (95% CI).

RESULTS

At least 1 virus was detected in 85% of cases and 76% of controls, and greater than or equal to 1 bacterium was detected in 70% of cases and controls. The presence of respiratory syncytial virus (RSV) (aOR, 16.6; 95% CI: 9.81-28.2), human metapneumovirus (HMPV) (13.0; 6.17-27.5) and Mycoplasma pneumonia e (27.7; 8.37-91.6) were most strongly associated with CAP. For RSV and HMPV, there were significant trends between lower cycle-threshold values indicating higher viral genomic loads, and higher aORs for CAP. The population-attributable fraction estimates of RSV, HMPV, human parainfluenza virus, influenza virus and M. pneumoniae were 33.3% (32.2-34.5), 11.2% (10.5-11.9), 3.7% (1.0-6.3), 2.3% (1.0-3.6) and 4.2% (4.1-4.4), respectively.

CONCLUSIONS

RSV, HMPV and M. pneumoniae were most strongly related to pediatric CAP and accounted for half of all cases. There were positive trends between increasing viral genomic loads of RSV and HMPV, and higher odds for CAP.

The Etiology of Community-Acquired Pneumonia Correlates with Serum Inflammatory Markers in Children

Community-acquired pneumonia (CAP) severely affects pediatric hospitalizations. This study assessed the contribution of CAP to hospitalizations, its etiology in relationship with age, and the inflammatory markers. Between 2013 and 2018, 1064 CAP patients were hospitalized and diagnosed with bacterial/possibly bacterial pneumonia (BP), viral/possibly viral pneumonia (VP) and atypical pneumonia (AP). The etiology was confirmed using blood/pleural fluid culture/polymerase chain reaction (PCR), rapid antigen test/PCR in nasopharyngeal swabs, or serological studies. CAP accounted for 9.9% of hospitalizations and 14.8% of patient days. BP was diagnosed in 825 (77.5%), VP in 190 (17.9%), and AP in 49 (4.6%) cases; the confirmed etiology (n = 209; 20%) included mostly influenza (39%; n = 82), respiratory syncytial virus (RSV, 35%; n = 72), and Mycoplasma pneumoniae (19%; n = 39). VP frequency decreased with age (41% in < 3 mo to 9% in ≥ 60 mo), in contrast to AP (13% in ≥ 60 mo). Among the analyzed parameters, the best differentiating potential was shown by: C-reactive protein (CRP, AUCBP-VP = 0.675; 95% CI: 0.634−0.715), procalcitonin (AUCBP-AP = 0.73; 95% CI: 0.67−0.794), and CRP/procalcitonin (AUCAP-VP = 0.752; 95% CI: 0.67−0.83); a good positive predictive value (88.8%, 98.3%, and 91.6%, respectively) but a low negative predictive value (29.5%, 13.1%, and 40.7%, respectively) was observed. CAP influences hospital patient days more than the crude number of patients would suggest. On a clinical basis, BP is mainly recognized, although viral pneumonia is confirmed most often. RSV and influenza are responsible for a huge percentage of hospitalized cases, as well as M. pneumoniae in children aged ≥ 5 years. Serum inflammatory markers may help differentiate etiological factors.

Bacterial and Viral Coinfections with the Human Respiratory Syncytial Virus

The human respiratory syncytial virus (hRSV) is one of the leading causes of acute lower respiratory tract infections in children under five years old. Notably, hRSV infections can give way to pneumonia and predispose to other respiratory complications later in life, such as asthma. Even though the social and economic burden associated with hRSV infections is tremendous, there are no approved vaccines to date to prevent the disease caused by this pathogen. Recently, coinfections and superinfections have turned into an active field of study, and interactions between many viral and bacterial pathogens have been studied. hRSV is not an exception since polymicrobial infections involving this virus are common, especially when illness has evolved into pneumonia. Here, we review the epidemiology and recent findings regarding the main polymicrobial infections involving hRSV and several prevalent bacterial and viral respiratory pathogens, such as Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Klebsiella pneumoniae, human rhinoviruses, influenza A virus, human metapneumovirus, and human parainfluenza viruses. As reports of most polymicrobial infections involving hRSV lack a molecular basis explaining the interaction between hRSV and these pathogens, we believe this review article can serve as a starting point to interesting and very much needed research in this area.