Comparison of clinical features and co-infection between pneumonia caused by influenza virus A and pneumonia caused by influenza virus B among children / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To compare the clinical features and co-infection between pneumonia caused by influenza virus A (IVA) and pneumonia caused by influenza virus B (IVB) among children.</p><p><b>METHODS</b>A total of 165 children with pneumonia caused by influenza virus (IV) were included in the study. These subjects were divided into IVA(n=71) and IVB pneumonia groups (n=94) according to the subtypes of IV. The IVA pneumonia group was further divided into simple infection (n=14) and co-infection subgroups (n=57), and the IVB pneumonia group was also further divided into simple infection (n=27) and co-infection subgroups (n=67). Co-infection rate and pathogen spectrum were analysed in children with IV pneumonia.</p><p><b>RESULTS</b>The IVB pneumonia group had significantly increased mean age of onset and significantly prolonged mean duration of fever compared with the IVA pneumonia group (P<0.05). Co-infection rate among children with IV pneumonia was 75.2%, who were co-infected with bacteria (44.2%), Mycoplasma pneumoniae (MP, 21.8%) and other viruses (45.5%). Respiratory syncytial virus (RSV) was most common in children co-infected viruses (89% ). The rate of co-infection with RSV was significantly higher in the IVA pneumonia group than in the IVB pneumonia group. There were no significant differences in age, length of hospital stay, duration of fever, percentage of neutrophils, prealbumin, C-reactive protein, alanine aminotransferase, and creatine kinase-MB between the simple infection and co-infection subgroups of each group.</p><p><b>CONCLUSIONS</b>Children with IVB pneumonia have prolonged duration of fever and increased age of onset compared with those with IVA pneumonia. Co-infection rate is high among children with IV pneumonia, who may be co-infected with bacteria, viruses and MP. Co-infection with RSV is more common in children with IVA pneumonia. It is difficult to identify the presense of co-infection using clinical indices.</p>

Monitoring of influenza virus B and clinical features of pediatric pneumonia caused by influenza virus B only / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the epidemiological features of influenza virus B (IVB) in the winter and the clinical features of pediatric pneumonia caused by IVB only.</p><p><b>METHODS</b>A retrospective study was performed on the clinical data of children with respiratory infection who received pathogen testing and therapy at Soochow University Affiliated Children's Hospital during the winters of 2008, 2009, 2010 and 2011.</p><p><b>RESULTS</b>The positive rates of influenza viruses A and B in the winters of 2008, 2009, and 2010 were 0.89%, 5.49%, and 6.24% respectively; the positive rate of influenza viruses A and B in the winter of 2011 was 8.72%, significantly higher than those in 2008-2010. The positive rates of IVB in the winters of 2008, 2009, and 2010 were 0%, 0%, and 0.21% respectively; the positive rate of IVB in the winter of 2011 was 5.36%, which was significantly higher than in the years 2008 to 2010. Pneumonia caused by IVB was confirmed in 94 children during the winter of 2011, including 27 cases of pneumonia caused by IVB only. Most of children with pneumonia caused by IVB only were aged over 6 months. The common symptoms in the 27 children caused by IVB only were fever (85%), runny nose (89%), and cough (100%). Wheezing (26%) and dyspnea (7%) were also seen in some cases. Among the 27 children, 19% showed abnormal white blood cell count, 30% showed increased C-reactive protein, 70% showed decreased prealbumin, and none showed visible organ dysfunction. No specific imaging findings were seen in the children with pneumonia caused by IVB only. However, many abnormal humoral and cellular immunological parameters were found in the majority of these children. The average length of hospital stay was approximately one week, there were no critical patients and the prognosis was good.</p><p><b>CONCLUSIONS</b>Influenza viruses were at a peak level in inpatient children in the winter of 2011. IVB infection rate was gradually increasing. In children with pneumonia caused by IVB only, there are few critical patients, the symptoms are nonspecific and the prognosis is good.</p>

Mortality and morbidity of acute hypoxemic respiratory failure and acute respiratory distress syndrome in infants and young children / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Acute hypoxemic respiratory failure (AHRF) often develops acute respiratory distress syndrome (ARDS), and its incidence and mortalities in critically ill pediatric patients in China were 2% and 40% respectively. This study aimed at prospectively investigating incidence, causes, mortality and its risk factors, and any relationship to initial tidal volume (V(T)) levels of mechanical ventilation, in children £5 years of age with AHRF and ARDS.</p><p><b>METHODS</b>In 12 consecutive months in 23 pediatric intensive care units (PICU), AHRF and ARDS were identified in those requiring > 12 hour intratracheal mechanical ventilation and followed up for 90 days or until death or discharge. ARDS was diagnosed according to the American-European Consensus definitions. The mortality and ventilation free days (VFD) were measured as the primary outcome, and major complications, initial disease severity, and burden were measured as the secondary outcome.</p><p><b>RESULTS</b>In 13 491 PICU admissions, there were 439 AHRF, of which 345 (78.6%) developed ARDS, resulting in incidences of 3.3% and 2.6%, and corresponding mortalities of 30.3% and 32.8% respectively along with 8.2 and 6.7 times of relative risk of death in those with pneumonia (62.9%) and sepsis (33.7%) as major underlying diseases respectively. No association was found in V(T) levels during the first 7 days with mortality, nor for V(T) at levels < 6, 6 - 8, 8 - 10, and > 10 ml/kg in the first 3 days with mortality or length of VFD. By binary Logistic regression analyses, higher pediatric risk of mortality score III, higher initial oxygenation index, and age < 1 year were associated with higher mortality or shorter VFD in AHRF.</p><p><b>CONCLUSIONS</b>The incidence and mortalities of AHRF and ARDS in children £5 years were similar to or lower than the previously reported rates (in age up to 15 years), associated with initial disease severity and other confounders, but causal relationship for the initial V(T) levels as the independent factor to the major outcome was not found.</p>

Clinical characteristics of 14 critically ill children with 2009 influenza A (H1N1) / 中华儿科杂志

<p><b>OBJECTIVE</b>To summarize characteristics and outcomes of critically ill children with 2009 influenza A (H1N1).</p><p><b>METHOD</b>A prospective observational study of 14 critically ill children with 2009 influenza A (H1N1) in pediatric intensive care unit (PICU) in Suzhou between Oct. 1(st) 2009 and Dec. 25(th) 2009. The primary outcome measures included frequency and duration of mechanical ventilation and duration of ICU stay.</p><p><b>RESULT</b>Critical illness occurred in 14 patients with confirmed (n = 14), community-acquired 2009 influenza A virus (H1N1) infection. The mean (SD) age of the 14 patients with confirmed 2009 influenza A (H1N1) was (4.91 ± 4.14) years, 7 were female (50.0%). The median duration from symptom onset to hospital admission was (3.09 ± 1.30) days and from hospitalization to ICU admission was (0.95 ± 0.96) day. All the patients were severely hypoxemic [mean (SD) ratio of PaO2/FiO2 was (191.27 ± 80.58) mm Hg] at ICU admission. ARDS occurred in 11 cases (78.6%). Mechanical ventilation was applied for 10 patients (71.4%). The median duration of ventilation was (12.51 ± 10.03) days and ICU stay was (12.58 ± 10.65) days. The median length of time during which the real-time RT-PCR test results were positive was (17.27 ± 5.57) days; Comorbidities such as iron deficiency anemia, cerebral palsy and congenital heart disease were found in 8 cases (57.1%). The longer length of mechanical ventilation and ICU stay were found in cases with higher admission PRISM III Score and lower Pediatrics Critical Illness Score.</p><p><b>CONCLUSION</b>Critical illness due to 2009 influenza A (H1N1) in Suzhou occurred rapidly after hospital admission and was associated with severe hypoxemia, ARDS, a condition that required prolonged mechanical ventilation. There were myocardial damages in critically ill children with severe 2009 influenza A (H1N1).</p>