Epidemiology and risk factors for severe respiratory syncytial virus infections requiring pediatric intensive care admission in Hong Kong children.

PURPOSE: Respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infection in young children. However, there are limited data on severe RSV infection requiring pediatric intensive care unit (PICU) admission. This retrospective study described features of RSV-associated PICU admissions in Hong Kong and investigated factors for mortality and duration of PICU stay. METHODS: Children with laboratory-confirmed RSV infection and admitted to the PICUs of all eight government hospitals in Hong Kong between January 2009 and June 2011 were identified from computerized auditing systems and PICU databases. RSV in respiratory samples was detected by direct immunofluorescence and/or viral culture. The relationships between mortality and PICU duration and demographic and clinical factors were analyzed. RESULTS: A total of 118 (2.4 %) PICU admissions were identified among 4,912 RSV-positive pediatric cases in all hospitals. Sixty-five (55.6 %) patients were infants. PICU admissions were higher between October and March. Eight (6.8 %) patients died, but only two were infants. RSV-associated mortality was related to prior sick contact, presence of older siblings, neurodevelopmental conditions, chromosomal and genetic diseases, and bacterial co-infections, but none was significant following logistic regression analyses (odds ratio 9.36, 95 % confidence interval 0.91-96.03 for prior sick contact, p = 0.060). Chronic lung disease was the only risk factor for the duration of PICU admission (ß = 0.218, p = 0.017). CONCLUSIONS: The majority of RSV-infected children do not require PICU support. There is winter seasonality for RSV-associated PICU admission in Hong Kong. Prior sick contact is the only risk factor for RSV-associated mortality, whereas the presence of chronic lung disease is associated with longer PICU stay. The current risk-based approach of RSV prophylaxis may not be effective in reducing severe RSV infections.

Acute kidney injury in the paediatric intensive care unit: identification by modified RIFLE criteria.

OBJECTIVE: To evaluate the prevalence and outcome of acute kidney injury in paediatric intensive care units using the modified RIFLE score (pRIFLE). DESIGN: Historical cohort study. SETTING: A paediatric intensive care unit in a regional Hong Kong hospital. PATIENTS; All paediatric patients aged 1 month to 18 years admitted to a local paediatric intensive care unit in the years 2005 to 2007. MAIN OUTCOME MEASURES; For every paediatric intensive care unit admission, acute kidney injury was classified according to the pRIFLE criteria ("R" for risk, "I" for injury, "F" for failure, "L" for loss, and "E" for end-stage). Prevalence and outcome of acute kidney injury were therefore categorised according to the pRIFLE staging. RESULTS: A total of 140 such patient admissions constituted the study population. The point prevalence of acute kidney injury in these patients on admission was 46% (n=59), whilst 56% (n=78) endured acute kidney injury at some time during their paediatric intensive care unit stay. Worsening of pRIFLE grading during their intensive care unit admission was observed in 20% of the patients who had no acute kidney injury on admission, in 30% of those who had an initial "R" grade, and in 40% of those who had an initial "I" grade of acute kidney injury. Overall mortality in this cohort was 12%, which was significantly higher among patients with acute kidney injury. Having acute kidney injury of grade "F" on admission to the paediatric intensive care unit was an independent predictor of mortality (hazard ratio=5.94; 95% confidence interval, 1.06-33.36; P=0.043). CONCLUSION: Among critically ill paediatric patients, the pRIFLE score serves as a suitable classification of acute kidney injury when stratified according to clinical severity. It also provides prognostic information on mortality and renal outcomes.

Enzyme replacement therapy for mucopolysaccharidosis VI (Maroteaux-Lamy syndrome): experience in Hong Kong.

Mucopolysaccharidosis VI (Maroteaux-Lamy syndrome) is a very rare inherited lysosomal storage disease. We evaluated the efficacy and safety of weekly infusions of recombinant human arylsulfatase B as enzyme replacement therapy for two patients in whom this condition was advanced. The primary outcome variables were the distance walked in a 6-minute walk test, forced vital capacity, and ejection fraction. The secondary outcome variables were the number of stairs climbed in a 3-minute stair climbing test, joint mobility, urinary glycosaminoglycan excretion, auto-continuous positive airway pressure study and liver size. After 24 weeks of treatment, patient A walked 40 m (36%) and patient B walked 66 m (58%) more in the walk test than at baseline. After 48 weeks, in patient A the corresponding improvements were 142 m (129%) in the walk test and 33 stairs (60%) in the 3-minute stair climbing test, and in patient B the respective improvements were 198 m (174%) and 77 stairs (140%). There was a significant decline in urinary glycosaminoglycan excretion and improvement in range of motion of joints in both patients. The auto-continuous positive airway pressure study revealed improvements in patient A, while other efficacy variables remained static. There were no drug-related adverse events or allergic reactions reported during and after the infusions of recombinant human arylsulfatase B. Recombinant human arylsulfatase B significantly improves endurance and reduces urinary glycosaminoglycan excretion. The drug is generally safe and well tolerated.

Foreign body aspiration in Hong Kong Chinese children.

OBJECTIVES: To describe and compare the demographic, clinical, radiological, and bronchoscopy features and outcomes of children with foreign body aspiration in early- and late-diagnosis groups, to report the reasons for delay in diagnoses, and to determine what objects are commonly aspirated. DESIGN: Retrospective study. SETTING: Department of Paediatrics, Queen Elizabeth Hospital, Hong Kong. PATIENTS: All children younger than the age of 18 years with foreign body aspiration admitted to the study hospital from 1 January 1993 to 31 May 2006. RESULTS: Sixteen (59%) of the patients were categorised into the early-diagnosis group (correctly diagnosed foreign body aspiration<7 days of symptom onset) and 11 (41%) into the late-diagnosis group (correctly diagnosed>or=7 days after symptom onset). The common clinical manifestations of foreign body aspiration were persistent cough (100%) and history of choking (74%). Most children (82%) in the late-diagnosis group and 25% in early-diagnosis group (P=0.004) were misdiagnosed as respiratory infections and asthma. Intrabronchial granulation was more common in the late-diagnosis group (13% vs 55%, P=0.033). Peanuts and watermelon seeds accounted for 85% of the aspirations; 63% of the foreign body aspirations occurred around the Chinese New Year festival. CONCLUSION: Foreign body aspiration is difficult to diagnose in children. Misdiagnosis as asthma and respiratory infection can delay treatment and result in intrabronchial granuloma. We therefore suggest early bronchoscopy in suspicious cases. Parents should be cautious when giving peanuts and watermelon seeds to their children.