Objective To explore the clinical characteristics of acute lower respiratory tract infection in children after influenza,and to provide evidence-based basis for timely diagnosis and accurate treatment of acute lower respiratory tract infection in children after influenza. Methods Eighty- two patients with acute lower respiratory tract infection admitted to Shanghai Children′ s Medical Center from October 2016 to November 2017 were enrolled in our study. The clinical data of these patients were analyzed and influenza A or influenza B were confirmed by Filmarray platform. The clinical characteristics of patients with influenza A and influenza B,severe pneumonia and non-severe pneumonia,mechanical ventilation and non-mechanical ventilation were compared. Results The age distribution of the children ranged from 0. 13 to 15 years old, with 73 cases (89. 0％ ) being younger than 5 years old. There were 47 cases of influenza A (57. 3％ ) and 35 cases of influenza B (42. 7％ ). The proportions of cases in spring,summer,autumn and winter were 35. 3％ ,15. 9％ ,15. 9％ and 32. 9％ ,respectively. Congenital heart disease was the most common underlying disease (28 cases,34. 1％ ). Twenty-five(30. 5％ ) patients were diagnosed as severe pneumonia. Oseltamivir was added on the first to eighth days of the course with median time ( IQR) 2. 0 (3. 0) days. Thirteen (15. 9％ ) patients needed ventilator-assisted ventilation. There were significant differences in the incidence of influenza A and influenza B in summer (12 / 47 vs. 1 / 35,χ2 = 7. 7,P < 0. 01). Compared to non-severe pneu-monia,severe pneumonia was positively correlated with underlying diseases(17 / 25 vs. 18 / 57,χ2 = 9. 4,P <0. 01),digestive tract symptoms(10 / 25 vs. 6 / 57,χ2 = 9. 6,P < 0. 01) and high PCT level(8 / 23 vs. 8 / 56,χ2 = 3. 1,P < 0. 01),but negatively correlated with oseltamivir application[M(IQR)] [5. 0(2. 5) d vs. 2. 0 (1. 5)d,Z = - 6. 1,P < 0. 01]. There was significant difference in the proportion of influenza A/ B between ventilator group and non-ventilator group (11 / 2 vs. 36 / 33,χ2 = 4. 7,P < 0. 01). Conclusion Filmarray re-spiratory tract detection system can detect influenza virus infection quickly and accurately,providing a good basis for early diagnosis and treatment. Children under 5 years old are susceptible to influenza. Influenza in children mainly occurs in winter and spring. Influenza A mainly occurs in summer. Patients with influenza A infection,underlying diseases,digestive tract symptoms during the course of illness and elevated PCT are more likely to progress to severe illness or even use ventilator treatment. Early use of oseltamivir can improve the prognosis of the disease.

Objective To investigate the clinical value of the polymerase chain reaction (PCR) technique in detection of pediatric helicobacter pylori(HP) infection.Methods A total of 130 children with different digestive tract symptoms received esophagogastroduodenoscopy,and 120 children between 3 and 17 years old were enrolled.The gastric antrum mucosa was taken under the gastroscope for 2 blocks,and the gastric juice was absorbed as the specimen.One block of gastric antrum mucosa was examined histopathologi-cally,and the other block of gastric antrum mucosa and gastric juice were examined by PCR.We used the primers UreC,HP-16s,CSTP to detect HP,and then used the primers Cag750 and Cag595 to detect CagA. Results A total of 28 cases(23.33%) of upper gastrointestinal ulcer were detected by gastroscopy,and HP was detected by histopathological method in 26 cases(21.67%),and 41 cases(34.17%) were detected by PCR method.The detection rate of HP by PCR was significantly higher than that of HP in pathological method (χ2= 4.659,P = 0.031). By pathological examination of HP,14 cases (50%) and 12 cases (13.04%) with peptic ulcers and no peptic ulcers were detectd,and the difference in detection rate was statistically significant(χ2=17.275,P<0.001).Samples of children with peptic ulcers and no peptic ulcers were detected in 16 cases(57.14%) and 25 cases (27.17%) by PCR,and the difference in detection rate was statistically significant (χ2=8.572,P=0.003).The CagA were detected in 7 cases of peptic ulcers and 7 cases of non peptic ulcers by PCR,and the difference in detection rate was statistically significant(25.00%vs 7.61%,χ2=6.300,P=0.012).Conclusion The PCR method could quickly and sensitively detect the HP and its CagA gene,and the detection of gastric mucosa and gastric juice by PCR could improve the detection rate of HP.A combination of PCR and pathological method is suggested as the detection method for children′s HP infection.

Objective To investigate the clinical features and pathogenic types of suspected pertussis syndrome in infants,so as to provide reference for the treatment. Methods Seventy-one infants of suspected pertussis in Shanghai Children′s Medical Center from Nov 2016 to Aug 2017 were detected by the Filmarray which can detect Bordetella pertussis and 17 viruses. According to the results,the infants were divided into two groups:pertussis group(n=29) and pertussis-like group(n=42). According to the severity of the dis-ease,they were divided into mild group(n=50) and severe group(n=21). Clinical data was retrospectively analyzed and compared. Results All 71 infants came to the hospital with cough. Paroxysmal cough happened in 18 cases(62. 1％)in pertussis group,more common than that in pertussis-like group[9 cases(21. 4％)] (χ2 =12. 023,P<0. 01),and the WBC count,lymphocyte ratio,the mixed virus infection rate were higher in pertussis group than those in pertussis-like group[(20. 00 ± 8. 62) × 109/L vs. (13. 42 ± 6. 58) × 109/L,t=-3. 647,P<0. 01;(70. 38 ± 8. 97)％ vs. (56. 26 ± 20. 38)％,t = -3. 967,P <0. 01;22 cases(75. 9％) vs. 16 cases(38. 1％),χ2 =9. 836,P<0. 01]. The cases of mixed bacterial infection in pertussis-like group were 13(31. 0％),which was higher than that in pertussis group[3(10. 3％)](χ2 =4. 173,P<0. 05). The incidence of cyanosis was found in 12 cases(57. 1％)in severe group,which was more common than that of mild group[12 cases(24. 0％)](χ2 =7. 260,P<0. 01), and hospitalization days were(14. 5 ± 7. 8) days, which was higher than that in mild group[(7. 0 ± 3. 1)days] (t= -4. 250, P<0. 01). The infants in the pertussis group were given macrolides antibiotics and sulfamethoxazole complex,and the infants in the pertus-sis-like group were treated with antiviral and other specific treatment. Among 71 infants, 67 cases (94. 4％) were cured and 3 cases (4. 2％) were improved. Conclusion The clinical features of suspected pertussis in infants are not typical, so the early pathogenic diagnosis is very important. Filmarray detection system for multi PCR system can detect 20 kinds of pathogens with short operation time,which is very helpful for the early and rapid diagnosis of pathogens and rational use of drugs. It is worthy of clinical promotion.

Objective To investigate the effects of Helicobacter pylori( HP) on gut microbiota in children by comparing the difference of gastric microbiota between HP-positive and HP-negative individuals. Methods Genome was extracted from excrements of 8 HP-positive cases and 8 HP-negative cases. After genomic extraction,the hypervariable region of 16S rRNA gene were amplified and a small fragment library was constructed,and high-throughput sequencing was carried out, then the data of the lower machine was effectively sequenced by biological information processing. We could seek for the species that have changed significantly due to HP infection by comparing the differences in the composition of intestinal flora between the two groups. Results Compared with HP-negative group,HP-positive group showed less OTUs. The dif-fenece of biodiversity between them was conspicuous. The Caproiciproducens,Enterobacteriaceae,Enterobac-teriales,Blautia-obeum,Esherichia-albertli,human-gut-metagenome and Dorea in HP-positive group were sig-nificantly higher than HP-negative group,while the Bacteroides-uniformis, Bacteroidaceae and Bacteroides in HP-negative group were significantly higher than HP-positive group. Conclusion HP could significantly affect the structure and composition of gut microbiota in children.

Objective To evaluate the clinical efficacy and application value of FilmArray Respiratory Panel(FilmArray RP)for Mycoplasma pneumoniae(MP)detection.Methods Methodological evaluation.A total of 360 nasopharyngeal swabs or sputum samples were collected from hospitalized children with community acquired pneumonia in Shanghai Children′s Medical Center,Shanghai Jiao Tong University School of Medicine(SCMC)from November 2016 to May 2017.Among them, there were 197 males and 163 females.There were 185 cases in 0-2 years old group,116 cases in 3-6 years old group and 59 cases in 7-16 years old group.FilmArray RP and serological test were respectively used to detect MP infection. Polymerase chain reaction(PCR)was also performed on all the positive samples of MP detected by FilmArray RP,negative samples of FilmArray RP but positive by serological test and some negative samples of the two test methods selected by simple random sample.The results of FilmArray RP and serological test,the positive rates of different age groups detected by FilmArray RP and the rates of MP combined with virus were statistically analyzed by χ2test.Results Among 360 patients with community acquired pneumonia,39 (10.83%,39/360)were MP positive detected by FilmArray RP.In contrast,93 patients(25.83%,93/360)were diagnosed as MP infections using serological test.Results from the two methods were statistically significant(χ2=27.05, P=0.00).Among them, 39 cases of MP detected by FilmArray RP were also positive by PCR.Sixty-one negative samples of FilmArray RP but positive by serological test and 22 negative samples of the two test methods selected by simple random sample were also negative by PCR.Among the positive samples detected by FilmArray RP,the positive rate of patients aged 7-16 years(28.81%,17/59) was higher than that of patients aged 0-2 years(5.95%,11/185)and patients aged 3-6 years(9.48%,11/116).The positive rates of different age groups were statistically significant(χ2=24.54, P=0.00).The proportion of MP combined with virus infection in 0-2 years old group(81.82%,9/11)was higher than that in 3-6 years old group(45.45%,5/11)and 7-16 years old group(29.41%,5/17),the difference was statistically significant(χ2=7.41, P=0.03).Conclusions FilmArray RP is a rapid method in MP detection.It has great advantages in the detection of MP and virus mixed infection.

Objective:To explore the application value of FilmArray detection in children with acute lower respiratory tract infection and conduct economics analysis.Methods:From December 1, 2016 to November 30, 2017, 1 380 patients were enrolled in our study.Some children(FilmArray group) were tested for respiratory pathogens with FilmArray, while others (control group) were tested by 7-box antigen test of respiratory virus, gold colloid test of influenza and mycoplasma antibody.Those with underlying diseases were excluded.A total of 160 cases in the FilmArray group and 160 cases in the control group were obtained with tendency score matching method.The physical examination of pathogens, clinical indicators, usage of anti-infective drugs and hospitalization related costs were compared.Results:The positive rate of FilmArray test was significantly higher than that in control group (86.88% vs. 45.91%). The most common pathogens detected by FilmArray were adenovirus(39 cases), rhinovirus(34 cases), and parainfluenza virus(30 cases). In the FilmArray group, nine cases were positive for botulinum pertussis, accounting for 5.6% of the total.The hospitalization time of FilmArray group was shorter than that in control group [(8.89±6.23 days vs.(11.51±14.43)days]. In FilmArray group, the antibiotics were used for a shorter time, and 18 children did not use antibiotics during hospitalization.Compared with the control group, the hospitalization cost had no significant difference in the FilmArray group, but the antibiotic cost was less, as well as hospitalization time was shorter.The average hospitalization cost saved by using the FilmArray test was nearly 2 000 yuan per person. Conclusion:The application of FilmArray detection in children with acute lower respiratory tract infection can quickly and accurately identify a various infections of virus, bacteria and atypical pathogen, which guides using anti-infective drugs more reasonably.The application of FilmArray detection shortens the average hospitalization days of children, increases the utilization efficiency of medical resources, and reduces the medical cost and indirect economic loss of children’s families, which has certain economics significance.

Objective:To evaluate the clinical significance of molecular detection testing multiple pathogens in children with viral central nervous system infections.Methods:We retrospectively included 176 children who were suspected with central nervous system infection at Shanghai Children′s Medical Center from January 2017 to May 2021.Film Array Meningitis/Encephalitis Panel(FA-M/E) was used to test cerebrospinal fluid samples of these children.The results were analyzed compared with clinical symptoms and cerebrospinal fluid indices.Results:There were 34 samples with positive FA-M/E virus detection(19.32%, 34/176). Among the 34 samples, enterovirus was the most common pathogen(27 cases, 79.41%). In different combinations, the sensitivity and positive predictive value were all less than 90%.The median time for antiviral drugs used in FA-M/E virus-positive and negative children was 4.5(0, 8.5)d and 2.6(0, 2.0)d, respectively.The difference was statistically significant( P<0.05). Conclusion:Molecular tests of multiple pathogens can quickly and sensitively detect pathogens.It can improve the efficacy of clinical diagnosis of viral central nervous system infection.