[Multicenter study of human adenovirus infection in pediatric community-acquired pneumonia in China].

Objective: To investigate the predominant genotypes and epidemiological characteristics of human adenovirus (HAdV) in pediatric community-acquired pneumonia (CAP) in China. Methods: This was a repeated cross sectional study. Between November 2014 and November 2016, nasopharyngeal aspirates (NPAs) or throat swabs from each hospitalized pediatric patients diagnosed as CAP in 12 hospitals in Northern and Southern China were collected. Respiratory specimens were screened for 18 respiratory viruses including HAdV by using Luminex xTAG RVP Fast V2 multiplex Assay. Typing of HAdV and analysis for the epidemiological characteristic of HAdV were performed. Results: (1) A total of 2 723 hospitalized pediatric patients with CAP were enrolled in this study and 156 (5.7%, 156/2 723) respiratory specimens were positive for HAdV, and 74 (6.6%, 74/1 128) and 82 (5.1%, 82/1 595) were in Northern and Southern China, respectively. There was no significant difference in the positive detection rate between the Northern and Southern China. (2) In Northern China, the HAdV positive rate of children at the age of <6 months, 6 months-<1 years, 1-<3 years, 3-<5 years and ≥5 years was 5.9%(6/101), 6.7%(7/104), 10.3%(34/331), 4.1%(11/266) and 4.9%(16/326), respectively, and the incidence of HAdV infection peaked in children aged 1-3 years (χ(2)=11.511, P=0.021). While in Southern China the HAdV positive rate of children at the age of <6 months, 6 months-<1 years, 1-<3 years, 3-<5 years and ≥5 years was 2.2% (7/312), 4.6% (12/259), 6.3% (31/494), 7.3% (18/245) and 4.9%(14/285), respectively. There was no significant difference in the positive detection rate among age groups. (3) In 2015, the highest detection rate of HAdV in northern China was 12.5% (25/200) in winter, and in Southern China was 6.7% (35/525) in spring and 5.3% (19/357) in summer. (4) In 108 cases of HAdV positive specimens typing was done and 80 in cases classification was successfully performed.Totally 7 genotypes of HAdV, including HAdV-3 (n=32), HAdV-7 (n=9), HAdV-1 (n=12), HAdV-2 (n=15), HAdV-5 (n=10), HAdV-6 (n=1) and HAdV-4 (n=1), were detected. The predominant HAdV genotypes were HAdV-3 (30.8%, 8/26) and HAdV-7 (26.9%, 7/26) in Northern China, while HAdV-3 (44.4%, 24/54) and HAdV-2 (22.2%, 12/54) were the most prevalent genotypes in Southern China. Conclusions: HAdV is an important viral pathogen in pediatric CAP. The predominant HAdV genotypes and peak seasons of HAdV infections were different between Northern and Southern China. The predominant HAdV genotypes were HAdV-3 and HAdV-7 in Northern China, while HAdV-3 and HAdV-2 in Southern China. The peak season of HAdV infections was winter in Northern China. However, HAdV infections are more common in spring and summer in Southern China.

[Nasal continuous positive airway pressure ventilation in children with community-acquired pneumonia under five years of age: a prospective, multi-center clinical study].

Objective: To analyze the clinical characteristics of community-acquired pneumonia (CAP) in children under five years of age and analyze the safety and efficiency of nasal continuous positive airway pressure (NCPAP) ventilation for CAP in this population. Method: This was a prospective multicenter study. Children who were admitted to these six centers with CAP and met the NCPAP ventilation indications, aged from 29 d to 5 years, were continuously included during November 2013 to October 2015. The baseline data were collected and NCPAP ventilation were then followed up by operation standards, and the vital signs and arterial blood gas change at special time points were observed and recorded. Any side effect associated with NCPAP were recorded. For categorical variables, comparisons were performed using Fisher test. Rank-sum test and t test were performed respectively for abnormal and normal distribution continuous variables. The variables pre-NCPAP and post-NCPAP were analyzed by repeated measures ANOVA analysis. Result: Totally 145 children were included, and 13 children were excluded due to incomplete data. One hundred and two children(77.3%)were ≤12 months; 91 children (68.9%) were from rural area. NCPAP ventilation was effective in 123 children, with a response rate of 93.2%, were all discharged with a better condition; it was ineffective in 9 children(6.8%), and they were all intubated and went on mechanical ventilation, 5 were discharged with a better condition, and 4 died after gaving up treatment. The gender, age, body weight, residence, main symptoms, main signs, imaging diagnosis, medications, partial pressure of oxygen(PaO(2)), breath and heart rate before NCPAP treatment of two groups had no significant differences(allP>0.05). The rates of combining underlying diseases, trouble with feeding and cyanosis, and the partial pressure of carbon dioxide(PaCO(2) ) before NCPAP ventilation were higher in NCPAP ineffective group ((59±11 )vs.( 49±11) mmHg, 1 mmHg=0.133 kPa, t=-2.597, P=0.028); while the PaO(2)/fraction of inspiration O(2) (FiO(2) ) before NCPAP was lower((150±37) vs. (207±63) mmHg, t=2.697, P=0.008). The breathing, heart rate and PaCO(2) of NCPAP effective group decreased significantly, while the PaO(2) and PaO(2)/FiO(2) increased significantly after 2, 8, 24 h of NCPAP ventilation(all P=0.000). PaCO(2) in children with hypercapnia before NCPAP ventilation in NCPAP effective group decreased significantly ((48±9), (47±12), (45±11)vs.(58±7)mmHg, all P=0.000). All children tolerated well to NCPAP ventilation, and there were no severe side effects or complications associated with NCPAP ventilation. Conclusion: NCPAP ventilation is safe and effectively improved the oxygenation and hypercapnia in infants with CAP. But it may not work well in children with underlying diseases, manifest as difficulty in feeding/cyanosis and extremely high PaCO(2) or low PaO(2)/FiO(2), and they may need early intubation.