Analysis of cytokine levels, cytological findings, and MP-DNA level in bronchoalveolar lavage fluid of children with Mycoplasma pneumoniae pneumonia.

BACKGROUND: The present study was conducted to determine the inflammatory response in the lungs of children with Mycoplasma pneumoniae pneumonia (MPP). METHODS: This study retrospectively analyzed cytokine levels, cytological findings, and M. pneumoniae (MP)-DNA level in the bronchoalveolar lavage fluid (BALF) of 96 children with MPP. The study utilized Spearman's correlation method to evaluate the contribution of BALF and blood parameters in MPP children. RESULTS: (1) A total of 96 MPP children were classified into the Low MP-DNA MPP group (BALF MP-DNA ≤ 105 copies/mL) and the High MP-DNA MPP group (BALF MP-DNA > 105 copies/mL); the Non-fever MPP group (no fever during the entire course of pneumonia) and the Fever MPP group; the Defervescence MPP group (fever had subsided at the time of bronchoscopy) and the Fervescence MPP group; and the Mild MPP group and the Severe MPP group. (2) The High MP-DNA MPP, Fever MPP, Fervescence MPP, and Severe MPP groups had higher levels of interleukin (IL)-6, IL-10, and tumor necrosis factor-α (TNF-α) in their BALF (all p < .05). (3) The proportions of neutrophils and macrophages in the BALF of the High MP-DNA MPP and Fever MPP groups increased and decreased, respectively (all p < .05). (4) In the BALF of MPP children, MP-DNA, IL-6, IL-10, TNF-α, and interferon gamma (IFN-γ) levels positively correlated with neutrophil proportion while negatively correlated with macrophage proportion (all p < .05). (5) The MP-DNA, IL-6, IL-10, TNF-α, and IFN-γ levels in the BALF of MPP children were positively correlated with the levels of C-reactive protein, procalcitonin, lactic dehydrogenase, fibrinogen, and d-dimer, while they were negatively correlated with the albumin level (all p < .05). CONCLUSIONS: In children with MPP, the pulmonary inflammatory immune response was stronger in the High MP-DNA MPP, Fever MPP, Fervescence MPP, and Severe MPP groups. The relationship between pulmonary cytokine levels, MP-DNA load, and serum inflammatory parameters were found to be weak.

The difference in clinical features and prognosis of severe adenoviral pneumonia in children of different ages.

This study aims to analyze the difference in clinical features and prognosis of severe adenovirus pneumonia (SAP) in children of different ages and analyze the risk factors for poor prognosis in children with SAP. A retrospective observational study was performed to describe the clinical features and analyze the risk factors for death and postinfectious bronchiolitis obliterans (PIBO) in 303 children hospitalized with SAP from January 2015 through to January 2020. The participants were divided into four age groups: <6 months (n = 25, 8.3%); 6-12 months (n = 98, 32.3%); 12-36 months (n = 118, 38.9%); and >36 months (n = 62, 20.5%). Fever rate, peak, and duration were the lowest in the <6 months group, while no significant difference was found among other age groups. Serum levels of lactate dehydrogenase and a load of adenovirus were the lowest in the <6 months group, and the highest in the 6-12 and 12-36 months groups, respectively. A total of 80.9% of patients recovered, 3.3% of patients died, and 15.8% of patients were diagnosed with PIBO. The mortality rate showed no significance between age groups. The >36 months group had the highest recovery rate and the lowest incidence of PIBO, while the 6-12 months group had the lowest recovery rate and the highest incidence of PIBO. Independent risk factors for PIBO among all participants from the four groups were invasive mechanical ventilation, administration of intravenous steroids, duration of fever, and male gender. Independent risk factors for death among all participants from the four groups were hypercapnia, low albumin levels, and invasive mechanical ventilation. Risk factor analysis of different ages was not possible due to the limited sample size. The morbidity, clinical features, and prognosis of SAP are affected by children's ages. Pediatric patients with a longer duration of fever, hypercapnia, low serum albumin levels, invasive mechanical ventilation, and intravenous steroids use are more likely to develop a poor prognosis in SAP, especially if the patient is male.

Blockade of GITRL/GITR signaling pathway attenuates house dust mite-induced allergic asthma in mice through inhibition of MAPKs and NF-κB signaling.

GITRL/GITR signaling pathway plays an important role in allergy, inflammation, transplantation and autoimmunity. However, its role in asthma remains unclear. Thus, the present study aimed to investigate changes in this pathway and observe the therapeutic effect of its blocking on asthma. By using house dust mite-induced asthma model, changes of GITRL/GITR and its downstream molecules MAPKs (e.g., p38 MAPK, JNK and Erk) and NF-κB were observed. After that, GITRL in lung of mice was knocked down by recombinant adeno-associated virus to observe the impact on its downstream molecules and assess the therapeutic effect on asthma. These results showed that GITRL/GITR and its downstream molecules MAPKs/NF-κB were activated in asthmatic mice. This activation was suppressed after GITRL knockdown, and allergic airway inflammation and airway hyperresponsiveness were alleviated. These results demonstrate that GITRL/GITR-MAPKs/NF-κB signaling pathway participates in the pathogenesis of asthma. Blockade of GITRL/GITR signaling pathway exhibits protective effects in a mouse model of house dust mite-induced allergic asthma.

GITRL on dendritic cells aggravates house dust mite-induced airway inflammation and airway hyperresponsiveness by modulating CD4+ T cell differentiation.

BACKGROUND: Glucocorticoid-induced tumor necrosis factor receptor family-related protein ligand (GITRL) plays an important role in tumors, autoimmunity and inflammation. However, GITRL is not known to modulate the pathogenesis of allergic asthma. In this study, we investigated whether regulating GITRL expressed on dendritic cells (DCs) can prevent asthma and to elucidate its mechanism of action. METHODS: In vivo, the role of GITRL in modulating house dust mite (HDM)-induced asthma was assessed in adeno-associated virus (AAV)-shGITRL mice. In vitro, the role of GITRL expression by DCs was evaluated in LV-shGITRL bone marrow dendritic cells (BMDCs) under HDM stimulation. And the direct effect of GITRL was observed by stimulating splenocytes with GITRL protein. The effect of regulating GITRL on CD4+ T cell differentiation was detected. Further, GITRL mRNA in the peripheral blood of asthmatic children was tested. RESULTS: GITRL was significantly increased in HDM-challenged mice. In GITRL knockdown mice, allergen-induced airway inflammation, serum total IgE levels and airway hyperresponsiveness (AHR) were reduced. In vitro, GITRL expression on BMDCs was increased after HDM stimulation. Further, knocking down GITRL on DCs partially restored the balance of Th1/Th2 and Th17/Treg cells. Moreover, GITRL stimulation in vitro inhibited Treg cell differentiation and promoted Th2 and Th17 cell differentiation. Similarly, GITRL mRNA expression was increased in the peripheral blood from asthmatic children. CONCLUSIONS: This study identified a novel role for GITRL expressed by DCs as a positive regulator of CD4+ T cells responses in asthma, which implicates that GITRL inhibitors may be a potential immunotherapy for asthma.

How should our testing behaviour change with time in children in current COVID-19 pandemic?

BACKGROUNDS: More paediatric-confirmed cases have been reported with the global pandemic of COVID-19. This study aims to summarize the key points and supply suggestions on screening paediatric COVID-19 patients more appropriately. MATERIALS AND METHODS: We retrospectively included paediatric patients who have accepted SARS-CoV-2 RT-PCR testing in Children's Hospital of Chongqing Medical University (30 January 2020 to 13 February 2020) and compared them with paediatric-confirmed COVID-19 cases. Besides, a review was carried out by analysing all current literature about laboratory-confirmed paediatric cases with COVID-19. RESULTS: There were 46 suspected cases included in the descriptive study. The results of SARS-CoV-2 RT-PCR testing were all negative. Compared with paediatric-confirmed cases, the incidence of epidemic history was lower in suspected cases (P < .001). The rate of fever (P < .001), cough (P < .001), headache or dizziness (P < .001), vomiting (P < .001) and abdominal discomfort or distention (P = .01) were more observed in the included suspected children. There were more children having decreased WBC count in the confirmed group. In the literature review, twenty-nine studies were obtained with 488 paediatric COVID-19 cases. 88.6% of them had epidemiological history. Cough and fever were the most common symptoms. Compared with older patients, the incidence of fever, respiratory symptoms, lethargy and headache or dizziness was lower, while gastrointestinal symptoms were reported more. CONCLUSIONS: Children with a history of close contact with confirmed cases, manifested as cough and fever should be paid more attention to after excluding infection of other common pathogens. Atypical symptoms should not be over-emphasized in screening paediatric COVID-19. More studies are needed for guiding efficient recognition in paediatric COVID-19.

Allogeneic human umbilical cord-derived mesenchymal stem cells for severe bronchopulmonary dysplasia in children: study protocol for a randomized controlled trial (MSC-BPD trial).

BACKGROUND: Bronchopulmonary dysplasia (BPD) is a complex lung pathological lesion secondary to multiple factors and one of the most common chronic lung diseases. It has a poor prognosis, especially in preterm infants. However, effective therapies for this disease are lacking. Stem-cell therapy is a promising way to improve lung injury and abnormal alveolarization, and the human umbilical cord (hUC) is a good source of mesenchymal stem cells (MSCs), which have demonstrated efficacy in other diseases. We hypothesized that intravenously administered allogeneic hUC-MSCs are safe and effective for severe BPD. METHODS: The MSC-BPD trial is a randomized, single-center, open-label, dose-escalation, phase-II trial designed to investigate the safety and efficacy of hUC-MSCs in children with severe BPD. In this study, 72 patients will be enrolled and randomly divided into two intervention groups and one control group. Patients in the intervention groups will receive a low dose of hUC-MSCs (n = 24; 2.5 million cells/kg) or a high dose of hUC-MSCs (n = 24; 5 million cells/kg) in combination with traditional supportive treatments for BPD. The patients in the control group (n = 24) will be treated with traditional supportive treatments alone without hUC-MSCs. The primary outcome measures will be cumulative duration of oxygen therapy. Follow-up assessments will be performed at 1, 3, 6, 12, and 24 months post intervention, and the key outcome during follow-up will be changes on chest radiography. Statistical analyses will evaluate the efficacy of the hUC-MSC treatment. DISCUSSION: This will be the first randomized controlled trial to evaluate the safety and efficacy of intravenously administered hUC-MSCs in children with severe BPD. Its results should provide a new evidence-based therapy for severe BPD. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT03601416. Registered on 26 July 2018.

[Pathogen detection of 1 613 cases of hospitalized children with community acquired pneumonia].

OBJECTIVE: To investigate the distribution of pathogens of children with community acquired pneumonia (CAP) from the Chongqing area. METHODS: Nasopharyngeal specimens and blood specimens of 1 613 children with CAP were collected between January 2014 and December 2014 for bacterial culture and detection of 7 respiratory viruses and antibodies against Mycoplasma pneumoniae (MP). RESULTS: The overall positive rate of bacteria was 50.22% (810 cases). Hemophilus parainfluenzae (40.8%), Streptococcus pneumonia (29.7%) and Moraxelle catarrhalis (7.3%) were the predominant ones. Among the viruses, the top detected virus was respiratory syncytial virus (RSV, 58.3%), followed by parainfluenza virus type3 (17.4%) and adenovirus (14.3%). A total of 481 cases (29.82%) were MP-positive. The co-infection rate was 32.18% (519 cases), and the mixed infections of bacteria and viruses were common (47.4%). CONCLUSIONS: RSV and Hemophilus parainfluenzae are the major pathogens of CAP in children from the Chongqing area. MP is also an important pathogen. The co-infection of bacteria and viruses is prevalent.

[Values of a combination of multiple less invasive or non-invasive examinations in the diagnosis of pediatric sputum-negative pulmonary tuberculosis].

OBJECTIVE: To study the values of a combination of multiple less invasive or non-invasive examinations including chest computed tomography (CT) scan, purified protein derivative (PPD) test, erythrocyte sedimentation rate (ESR) test, and C-reactive protein (CRP) test in the diagnosis of pediatric sputum-negative pulmonary tuberculosis (TB). METHODS: A retrospective analysis was performed on the clinical data of 269 children with confirmed pulmonary TB. Clinical symptoms and test results were analyzed and compared between the sputum-negative group (161 patients) and the sputum-positive group (108 patients). RESULTS: The sputum-negative group had atypical clinical symptoms, with fewer typical or relatively specific imaging features compared with the sputum-positive group. The positive rates of PPD, ESR, and CRP tests for the sputum-negative group were 39.1%, 44.1%, and 56.5%, respectively, versus 55.6%, 79.6%, and 59.3% for the sputum-positive group. There were significant differences in the positive rates of PPD and ESR tests between the two groups (P<0.05). More than 80% of the patients in each group were diagnosed with pulmonary TB according to three or four less invasive or non-invasive tests, without significant difference in the positive rate between the two groups (P>0.05). Forty-six patients in the sputum-negative group underwent bronchoscopy, and morphological changes with a diagnostic value and/or etiological and pathological evidence were observed in 40 (87.0%) of them. CONCLUSIONS: The diagnosis rate of pediatric sputum-negative pulmonary TB can be increased by combining tests including chest CT scan, PPD test, ESR test, and CRP test. Bronchoscopy is a reliable method for the auxiliary diagnosis of pediatric sputum-negative pulmonary TB if the combining tests cannot provide compelling evidence.

[Diagnosis of children with occult bronchial foreign body].

OBJECTIVE: To investigate the clinical manifestation of children with occult bronchial foreign body, to analyze the reasons of misdiagnosis, to summarize the way of diagnosis and to emphasize the value of bronchoscopy in diagnosis and treatment of children with such disease. METHOD: A retrospective analysis of 22 cases of occult bronchial foreign body diagnosed and treated with bronchoscopy in Children's Hospital of Chongqing Medical University during the period from March 1, 2009 to February 28, 2014. RESULT: Of the 22 cases, 15 were male and 7 female. Their age ranged from nine months and eight days to fourteen years and six months. The course of disease ranged in length from six days to one year. It took us one to thirty-three days in diagnosing the problem. They or their parents all denied aspirating foreign body and the patients did not have irritating chokes. They did not have tracheal displacement or flapping sound. There were no direct signs of bronchial foreign body in their imaging examination. Twenty-one patients were diagnosed as pneumonia before bronchoscopy, and the remaining one was diagnosed as tuberculosis. All of the patients were complicated with infection; atelectasis was found in 15 cases/times, lung consolidation in 10 cases/times, emphysema in 4, pleural effusion in 5, bronchiectasis in 4, one case had respiratory failure, one case had septicemia. The clinical symptoms were relieved in the patients after bronchoscopy, 3 cases were cured, 19 cases were improved. CONCLUSION: Occult bronchial foreign body with certain complications and great harm is hard to diagnose. We should pay more attention to the important clues, such as a child with repeated pulmonary infection, indirect signs of airway obstruction and difficult to treat. Early bronchoscopy will be useful to improve diagnostics once the vital clue is found.

[Diagnostic values of bronchoscopy and multi-slice spiral CT for congenital dysplasia of the respiratory system in infants: a comparative study].

OBJECTIVE: To investigate and compare the diagnostic values of bronchoscopy and multi-slice spiral computed tomography (CT) for congenital dysplasia of the respiratory system in infants. METHODS: Analysis was performed on the clinical data, bronchoscopic findings and multi-slice spiral CT findings of 319 infants (≤1 years old) who underwent bronchoscopy and/or multi-slice spiral CT and were diagnosed with congenital dysplasia of the respiratory system. RESULTS: A total of 476 cases of congenital dysplasia of the respiratory system were found in the 319 infants, including primary dysplasia of the respiratory system (392 cases) and compressive dysplasia of the respiratory system (84 cases). Of the 392 cases of primary dysplasia of the respiratory system, 225 (57.4%) were diagnosed by bronchoscopy versus 167 (42.6%) by multi-slice spiral CT. There were significant differences in etiological diagnosis between bronchoscopy and multi-slice spiral CT in infants with congenital dysplasia of the respiratory system (P<0.05). All 76 cases of primary dysplasia of the respiratory system caused by tracheobronchomalacia were diagnosed by bronchoscopy and all 17 cases of primary dysplasia of the respiratory system caused by lung tissue dysplasia were diagnosed by multi-slice spiral CT. Of the 84 cases of compressive dysplasia of the respiratory system, 74 cases were diagnosed by multi-slice spiral CT and only 10 cases were diagnosed by bronchoscopy. CONCLUSIONS: Compared with multi-slice spiral CT, bronchoscopy can detect primary dysplasia of the respiratory system more directly. Bronchoscopy is valuable in the confirmed diagnosis of tracheobronchomalacia. Multi-slice spiral CT has a higher diagnostic value for lung tissue dysplasia than bronchoscopy.

[Analysis of 53 cases with bronchoscopically confirmed pediatric tracheobronchomalacia].

OBJECTIVE: Tracheobronchomalacia is one of the common respiratory tract dysplasia in children. Its symptoms are nonspecific, and routine methods are unreliable in the assessment of tracheobronchomalacia in children. In addition, many physicians are confused about its clinical characteristics, so tracheobronchomalacia is often underdiagnosed. The purpose of this study was to explore the clinical features of tracheobronchomalacia in children and to investigate the diagnostic value of flexible bronchoscopy for children with tracheobronchomalacia. METHOD: For diagnosis and treatment, 229 children out of 4725 patients hospitalized in the division of respiratory disorders were examined by Olympus BF3c-20 flexible bronchoscopy or by Olympus BF-P20 flexible bronchoscopy under general anesthesia with propofol, in Chongqing Children's Hosptial from April 2004 to April 2006. Fifty-three cases were confirmed to have tracheobronchomalacia by bronchoscopy, patients' data including airway lesion, age, sex, clinical characteristics, aided examinations, treatment, final outcomes, were collected and analyzed. RESULTS: (1) Of the 53 children with tracheobronchomalacia, 31 were not suspected for this diagnosis prior to bronchoscopy, who were instead misdiagnosed as refractory pneumonia, difficult-to-control asthma, bronchial foreign body, bronchopulmonary dysplasia and pulmonary atelectasis of unknown origin or bronchiolitis. (2) In the 53 children with tracheobronchomalacia aged one month to eight years, 41 were infants, 6 were younger than two years, 4 were younger than 3 years and the rest 2 cases were older than 3 years. The risk of tracheobronchomalacia related inversely with ages. Ten cases were girls and 43 were boys. (3) Eleven cases had tracheomalacia, 24 bronchomalacia, 18 tracheobronchomalacia; 12 cases had malacia on left lung, 11 on right lung, 19 on both sides; 21 children were mild cases, 25 moderate cases, 7 severe cases. (4) In the 53 children with tracheobronchomalacia, 28 had recurrent or prolonged wheezing, 16 chronic cough, 5 recurrent respiratory infections, 2 atelectasis of unknown origin, and 2 dyspnea. CONCLUSIONS: The infants and toddlers seem to be predisposed more to the bronchomalacia than the older children. Clinical features of children with airway malacia were variable and atypical, expiratory stridor and cough are the most commonly reported symptoms. Flexible bronchoscopy should be regarded as a "golden standard" method for diagnosing TBM.

[Clinical characteristics of 12 persistently wheezing children with human bocavirus infection].

OBJECTIVE: The impact of human bocavirus (HBoV), a newly identified human parvovirus, on childhood persistent wheezing has not been identified. In this study, the clinical features of infantile persistent wheezing induced by HBoV was analyzed. METHODS: Tracheal aspirates were collected by bronchofibroscope or nasopharyngeal (NP) aspirates from April, 2006 to January, 2007. HBoV DNA in the tracheal aspirates of 33 children with persistent wheezing and in NP aspirates of 6 children with persistent wheezing, who had at least or more than four weeks wheezing. RSV was identified by virus isolation in Hep-2 cells and antigen detetion by direct immunofluorescence assay (DIFA) which was also used for diagnosis of adenovirus, influenza A and B, parainfluenza 1, 2, 3 infection. RESULTS: Of the 39 children with persistent wheezing, 12 cases (31%) were positive for HBoV DNA. Age of HBoV-positive patients ranged from 2 month to 1 year. The results of sequencing of PCR products proved that sequences of HBoV DNA from these 12 samples were exactly identical to the those of HBoV stored in GeneBank (accession numbers DQ000495 and DQ000496). Two cases with HBoV infection were found to be co-infected with RSV. Ten of the 12 HBoV-positive samples were collected during the period from winter to spring (1 in November, 4 in December, 2 in January and 3 in April), the other two HBoV-positive samples were collected during the period from summer to autumn (1 in May and the other in July). Seven of the 12 HBoV DNA-positive patients had fever, 5 of them had high fever. Significantly more patients with HBoV infection had fever as compared to patients with RSV infection. All the HBoV positive patients showed abnormal findings on chest X ray such as interstitial infiltrates, lung infiltration and hyperinflation. Abnormal findings on chest X ray were found in higher proportion of HBoV positive patients as compared with RSV positive patients. And other manifestations such as wheezing, cough and respiratory distress had no significant difference between HBoV and RSV infected patients. CONCLUSIONS: This study further demonstrated that HBoV probably is a common pathogen of lower respiratory infection in children and might particularly be associated with persistent wheezing.