Viral and Atypical Bacterial Detection in Young Nepalese Children Hospitalized with Severe Pneumonia

Clinical and prognostic insights into Chlamydia trachomatis in pediatric acute respiratory infections: evidence from targeted next-generation sequencing of 5,021 cases

BACKGROUND

Chlamydia trachomatis (CT) is a major cause of respiratory tract infections in children. The primary objective of this research was to evaluate the infection status and clinical manifestations associated with C. trachomatis in these pediatric patients.

METHODS

From April 2021 to November 2023, a total of 5,021 hospitalized children with acute respiratory tract infections were collected at the Guangxi Maternal and Child Health Hospital. tNGS was used to detect pathogens in their respiratory samples.

RESULTS

Among the 5,021 hospitalized pediatric patients with acute respiratory tract infections, targeted next-generation sequencing (tNGS) detected C. trachomatis in 138 cases, with a detection rate of 2.75%. Among the 138 cases positive for C. trachomatis, 10 were identified as single C. trachomatis infection, while 128 cases involved co-infections with other pathogens. A total of 36 additional pathogens were detected in children with mixed Chlamydia trachomatis infections, with Pneumocystis jirovecii being the most frequently detected. In children with C. trachomatis infection, pulmonary consolidation and hypoxemia were the most commonly observed respiratory complications, whereas anemia and liver function impairment were the primary complications affecting other organ systems. The median duration of hospitalization for the 138 children was 8 days. Among the 138 children with C. trachomatis infection, 108 cases (78.26%) required respiratory support, and 11 cases (7.97%) required ICU admission.

CONCLUSION

The detection rate of C. trachomatis among hospitalized pediatric patients with respiratory tract infections was 2.75%. This study delineates the clinical manifestations and infection patterns of C. trachomatis in Guangxi, China.

The application value of targeted next-generation sequencing using bronchoalveolar lavage fluid samples in community-acquired pneumonia in children

BACKGROUND

The precise identification of pathogens responsible for community-acquired pneumonia (CAP) in children is essential for effective treatment. However, the performance of targeted next-generation sequencing (tNGS) in the detection of pathogens associated with CAP in children remains unclear.

METHODS

In this study, 216 children diagnosed with CAP were enrolled, and bronchoalveolar lavage fluid (BALF) samples underwent detection through tNGS, culture, and multiplex quantitative polymerase chain reaction (qPCR).

RESULTS

In 208 children, tNGS identified a total of 389 strains of microorganisms, including 111 Mycoplasma pneumoniae, 123 bacteria, 127 viruses, and 28 fungi. Among the cases, 89 presented as single-pathogen detection, while 119 exhibited multiple pathogens co-detection. The positive detection rates of bacteria and fungi through tNGS were significantly higher than those achieved through the traditional culture method, with rates of 56.9 % vs 8.3 % for bacteria and 13.0 % vs 4.2 % for fungi, respectively. The overall agreement between tNGS and multiplex qPCR ranged from 89.4 % to 99.1 %, with Kappa values ranging from 0.541 to 0.912 (P = 0.000).

CONCLUSIONS

The tNGS technique demonstrates rapid and effective capabilities in identifying a wide array of pathogens with a detection sensitivity that surpasses traditional culture methodologies while exhibiting a high degree of consistency with multiplex qPCR in detecting respiratory viruses. The tNGS detection method can serve as an important complement to traditional diagnostic approaches; however, caution must be exercised when interpreting tNGS findings due to its heightened sensitivity which may lead to identification of pathogens that are not necessarily responsible for causing disease.

Epidemiological characteristics of severe community-acquired pneumonia in children admitted to two tertiary hospitals in Shihezi, Xinjiang Region, China in 2023: a cross-sectional analysis

Background

Severe community-acquired pneumonia (SCAP) in children is associated with high morbidity and mortality, and the data of epidemiological characteristics of SCAP in Shihezi area were inadequate. The main pathogens responsible for SCAP may vary dramatically according to the geographical area. We identified two tertiary hospitals with better medical level and the largest number of hospitalized children in Shihezi as sentinel hospitals. The primary purpose of the study is to cross-sectionally summarize the epidemiological characteristics of SCAP in children admitted to hospitals in Shihezi, Xinjiang, China in 2023.

Methods

SCAP was defined as involving the respiratory and other systems, accompanied by significant systemic toxic symptoms. We prospectively included all patients <15 years old who diagnosed with SCAP according to the SCAP diagnostic criteria. We enrolled all patients <15 years who were diagnosed with SCAP during the study period (January to December 2023), a total of 309 cases were included from two sentinel hospitals in Shihezi, Xinjiang, from January to December 2023. Basic information and clinical data were collected on a standardized questionnaire, and respiratory samples were obtained for the detection of 27 respiratory pathogens using a panel, targeted next-generation sequencing (t-NGS), and metagenomic next-generation sequencing (mNGS).

Results

We enrolled 309 patients aged 1-14 years: 157 males (50.8%) and 152 females (49.2%). There were 45 infants (1 month to 1 year, 14.6%), 33 toddlers (>1-3 years, 10.7%), 121 preschool children (>3-7 years, 39.2%), and 110 school-age children (>7-14 years, 35.6%). Overall, the number of SCAP cases in spring was 39 (12.6%), in summer was 44 (14.2%), in autumn was 137 (44.3%), and in winter was 89 (28.8%). A total of 572 pathogens were detected in this study, primarily Mycoplasma pneumoniae (MP) (n=120, 21.0%), respiratory syncytial virus (RSV) (n=82 strains, 14.3%), and Streptococcus pneumoniae (SP) (n=67, 11.7%). MP was prevalent mainly during the cold season of autumn, with its detection starting from July and reaching a peak detection rate in November. By studying the interaction among 22 common respiratory pathogens, we found a strong negative correlation between MP and SP, yet the highest number of co-infected cases involved MP and SP. Seventy-six (63.3% of all MP) SCAP were identified as macrolide-resistant (all with mutations at the A2063G site). MP SCAP was associated with prolonged illness duration and fever spikes. We observed incidence of pediatric SCAP showed an inverse trend with PM2.5 level changes.

Conclusions

The most common pathogens responsible for SCAP in the Shihezi region in 2023 were MP, RSV, and SP. MP was the primary cause of SCAP in children, and increased risk of co-infections, and high prevalence of macrolides resistance-all related to mutations at the A2063G site. Early identification of SCAP pathogen epidemiological characteristics can reduce severe case occurrence.

Diagnosis and Prognostic Analysis of Mycoplasma pneumoniae Pneumonia in Children Based on High-Resolution Computed Tomography

Mycoplasma pneumoniae (MP) is defined as a common cause of pulmonary infections and accounts for up to four over ten of pneumonia in children over age 5. This study was aimed to explore the diagnosis and prognosis of mycoplasma pneumoniae pneumonia (MPP) in children using high-resolution computed tomography (CT) (HRCT). 71 children hospitalized with MPP were undertaken as the research objects to observe the incidence rate, occurrence time, and duration of the clinical symptoms and pathological signs. The chest HRCT and pulmonary ventilation function (PVF) were examined in the acute phase, the second phase re-examination period, and the third phase re-examination period. Relevant indicators were statistically analyzed to determine the change rules of chest HRCT and PVF and correlation between the two. Clinically, the children with MPP suffered from fever, cough, and sore throat. In addition to the above symptoms, children with MPP had different degrees of PVF impairment. Compared with the group with normal HRCT results, the forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF), forced expiratory flow at 25% forced expiratory volume (FEF25), forced expiratory flow at 50% forced expiratory volume (FEF50), forced expiratory flow at 75% forced expiratory volume (FEF75), and maximum mid-expiratory flow (MMEF75/25) of children in bronchopneumonia group, segmental pneumonia group, and lobar pneumonia group were obviously reduced, showing statistically great differences (P < 0.05). Compared with the case in acute phase, the PVF indicators of children in the re-examination phases were much higher, with greatly statistical differences (P < 0.05). In children with MPP, both the large and small airways were affected, but the recovery of the small airways was slow. Pulmonary HRCT and PVF can be undertaken as important indicators to judge the severity and prognosis of MPP in school-age children.