The severe acute respiratory syndrome (SARS) is responsible for the first pandemic of the 21st century. Within months after its emergence in Guangdong Province in mainland China, it had affected more than 8000 patients and caused 774 deaths in 26 countries on five continents. It illustrated dramatically the potential of air travel and globalization for the dissemination of an emerging infectious disease and highlighted the need for a coordinated global response to contain such disease threats. We review the cause, epidemiology, and clinical features of the disease.

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The severe acute respiratory syndrome.

These pediatric hypertension guidelines are an update to the 2004 “Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents.” Significant changes in these guidelines include (1) the replacement of the term “prehypertension” with the term “elevated blood pressure,” (2) new normative pediatric blood pressure (BP) tables based on normal-weight children, (3) a simplified screening table for identifying BPs needing further evaluation, (4) a simplified BP classification in adolescents ≥13 years of age that aligns with the forthcoming American Heart Association and American College of Cardiology adult BP guidelines, (5) a more limited recommendation to perform screening BP measurements only at preventive care visits, (6) streamlined recommendations on the initial evaluation and management of abnormal BPs, (7) an expanded role for ambulatory BP monitoring in the diagnosis and management of pediatric hypertension, and (8) revised recommendations on when to perform echocardiography in the evaluation of newly diagnosed hypertensive pediatric patients (generally only before medication initiation), along with a revised definition of left ventricular hypertrophy. These guidelines include 30 Key Action Statements and 27 additional recommendations derived from a comprehensive review of almost 15 000 published articles between January 2004 and July 2016. Each Key Action Statement includes level of evidence, benefit-harm relationship, and strength of recommendation. This clinical practice guideline, endorsed by the American Heart Association, is intended to foster a patient- and family-centered approach to care, reduce unnecessary and costly medical interventions, improve patient diagnoses and outcomes, support implementation, and provide direction for future research.

Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents.

OBJECTIVES: This revised clinical practice guideline, intended for use by primary care clinicians, provides recommendations for the diagnosis and management of the obstructive sleep apnea syndrome (OSAS) in children and adolescents. This practice guideline focuses on uncomplicated childhood OSAS, that is, OSAS associated with adenotonsillar hypertrophy and/or obesity in an otherwise healthy child who is being treated in the primary care setting. METHODS: Of 3166 articles from 1999–2010, 350 provided relevant data. Most articles were level II–IV. The resulting evidence report was used to formulate recommendations. RESULTS AND CONCLUSIONS: The following recommendations are made. (1) All children/adolescents should be screened for snoring. (2) Polysomnography should be performed in children/adolescents with snoring and symptoms/signs of OSAS; if polysomnography is not available, then alternative diagnostic tests or referral to a specialist for more extensive evaluation may be considered. (3) Adenotonsillectomy is recommended as the first-line treatment of patients with adenotonsillar hypertrophy. (4) High-risk patients should be monitored as inpatients postoperatively. (5) Patients should be reevaluated postoperatively to determine whether further treatment is required. Objective testing should be performed in patients who are high risk or have persistent symptoms/signs of OSAS after therapy. (6) Continuous positive airway pressure is recommended as treatment if adenotonsillectomy is not performed or if OSAS persists postoperatively. (7) Weight loss is recommended in addition to other therapy in patients who are overweight or obese. (8) Intranasal corticosteroids are an option for children with mild OSAS in whom adenotonsillectomy is contraindicated or for mild postoperative OSAS.

/pdf/diagnosis-and-management-of-childhood-obstructive-sleep-2wes17zrfk.pdf

Diagnosis and Management of Childhood Obstructive Sleep Apnea Syndrome

Sleep-induced apnea and disordered breathing refers to intermittent, cyclical cessations or reductions of airflow, with or without obstructions of the upper airway (OSA). In the presence of an anat...

Pathophysiology of Sleep Apnea

School closure and management practices during coronavirus outbreaks including COVID-19: a rapid systematic review.

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(03)13364-8.pdf

Clinical presentations and outcome of severe acute respiratory syndrome in children

OBJECTIVES: The aims of our study were: (1) to determine the prevalence of asymptomatic hepatic steatosis and presumed nonalcoholic steatohepatitis, in our local population of obese Chinese children referred for medical assessment; and (2) to assess the correlation between severity of ultrasonographic hepatic steatosis and degree of obesity, insulin resistance and serum biochemical abnormalities. DESIGN: Cross-sectional study. METHODS: In total, 84 obese children, 25 girls and 59 boys with median age and body mass index (BMI) of 12.0 years (interquartile range (IR): 9.5–14.0) and 30.3 kg/m2 (IR: 27.1–33.4), respectively, referred for medical assessment were studied. All subjects underwent physical examination, anthropometric and dual energy X-ray absorptiometry (DEXA) scan measurements and real-time ultrasonographic (US) examination of the liver. Fasting blood samples were collected for the measurement of liver function, hepatitis status, levels of serum glucose and insulin and lipid profile. Degree of fatty infiltration of the liver was graded according to ultrasonic appearance of liver echotexture, liver–diaphragm differentiation in echo amplitude, hepatic echo penetration and clarity of hepatic blood vessels. RESULTS: All recruited subjects had no history of alcohol abuse and tests for Hepatitis B or C virus were negative. Thorough examination showed all of them to be in general good health without signs of chronic liver disease. Hepatic steatosis identified by defined ultrasonic appearances was diagnosed in 65 subjects (77%); 17 girls and 48 boys. The severity of fatty liver was positively related to anthropometric measurements including BMI, waist and hip circumference, subscapular skinfold thickness; insulin resistance markers [QUICKI and homeostasis model assessment (HOMA)], and hypertriglyceridaemia. Multvariate ordinal regression analysis showed that BMI and raised alanine aminotransferase (ALT) were positively associated with fatty liver. Combination of hepatic steatosis with raised ALT (presumptive NASH) was found in 19 subjects (24%). This group of patients had significantly higher waist hip ratio and conicity index compared to those with isolated hepatic steatosis. Boys with presumed NASH were also found to have significantly higher insulin resistance. CONCLUSION: Nonalcoholic fatty liver disease (NAFLD) was common among our cohort of obese children referred for medical assessment. The prevalence of simple steatosis and presumed NASH was 77 and 24%, respectively. The severity of US steatosis was positively correlated with BMI, raised ALT, insulin resistance and hypertryglyceridaemia. Ultrasonography being noninvasive and readily available could be used for the monitoring of the progression of hepatic steatosis. Further longitudinal studies are required to determine the natural disease progression and the role of insulin resistance and other factors in the pathophysiology of NAFLD.

Hepatic steatosis in obese Chinese children

Rationale: We have previously reported that the six-minute-walk test (6MWT) is a reliable and valid functional test for assessing exercise tolerance and endurance. There is a lack of pediatric standard reference for the 6MWT.Objectives: To construct height-specific standards for the 6MWT for children aged 7 to 16 years.Methods: The anthropometric data, spirometric lung function, and six-minute-walk distance (6MWD) of Chinese children aged 7 to 16 years were prospectively measured using standardized protocols. The findings were used to construct height-specific standards for the 6MWT. The least mean square (LMS) method using maximum penalized likelihood was used to facilitate model fitting. Factors significantly associated with 6MWD were also determined.Measurements and Main Results: From January 2005 to April 2006, a total of 1,445 subjects were studied. The measured variables showed a normal distribution. Height-specific reference standards for 6MWT were constructed for both male and female children. For...

https://www.atsjournals.org/doi/pdf/10.1164/rccm.200607-883OC

Standard reference for the six-minute-walk test in healthy children aged 7 to 16 years.

Methods: Sixty four obese patients underwent physical examination, standardised pulmonary function tests (spirometry, lung volumes, and single breath diffusion capacity for carbon monoxide), and DEXA scan measurements. The trunk and subtotal (total - head) body fat mass were used as surrogate index of body adiposity. 

Results: Sixteen girls and 48 boys with median age and body mass index (BMI) of 12 years (interquartile range (IQR): 10–14) and 30.1 kg/m2 (IQR: 27.2–32.8) respectively were studied. None of the patients had clinical evidence of cardiopulmonary disease. Reduction in functional residual capacity (median FRC 93% predicted, IQR: 68.5–116.5%) and impairment of diffusion capacity (median DLco 83.5% predicted, IQR: 70.0–100.7%) were the most common abnormalities in our cohort, being observed in 30 (46%) and 21 (33%) patients respectively. Obstructive ventilatory impairment was found in three patients. There was significant negative correlation between the degree of reduction of FRC but not DLco with DEXA scan measurements, but such a relation was not found when BMI was used as the indicator of obesity. 

Conclusion: Reduction in FRC and diffusion impairment were the commonest abnormalities found in our cohort of obese patients. Reduction in static lung volume was correlated with the degree of obesity.

https://adc.bmj.com/content/archdischild/88/4/361.full.pdf

The effects of obesity on pulmonary function

Background: Childhood obstructive sleep apnoea (OSA) is increasingly being recognized. Its effect on blood pressure (BP) elevation and hypertension is still controversial.
 Objective: To evaluate the association between obstructive sleep apnoea and ambulatory BP in children.
 Methods: Children aged 6 to 13 years from randomly selected schools were invited to undergo overnight sleep study and ambulatory BP monitoring after completing a validated OSA questionnaire. OSA was diagnosed if obstructive apnoea-hypopnoea index (AHI) > 1, and normal controls had AHI 5).
 Results: Three hundred and six subjects had valid sleep and daytime BP data. Children with OSA had significantly higher blood pressure than normal healthy children during both sleep and wakefulness. The BP levels increased with the severity of OSA, and children with moderate-to-severe disease (AHI > 5) were at significantly higher risk for nocturnal systolic (OR = 3.9 [95% CI: 1.4-10.5]) and diastolic hypertension (OR = 3.3 [95% CI: 1.4-8.1]). Multiple linear regression revealed a significant association between oxygen desaturation index and AHI with daytime and nocturnal BP respectively independent of obesity.
 Conclusions: OSA was associated with elevated daytime and nocturnal BP, and it is an independent predictor of nocturnal hypertension. This has important clinical implications as childhood elevated BP predicts future cardiovascular risks. Future studies should examine the effect of therapy for OSA on BP changes.

https://thorax.bmj.com/content/thoraxjnl/63/9/803.full.pdf

Albert M. Li

Papers

Clinical presentations and outcome of severe acute respiratory syndrome in children

Hepatic steatosis in obese Chinese children

Standard reference for the six-minute-walk test in healthy children aged 7 to 16 years.

The effects of obesity on pulmonary function

Ambulatory blood pressure in children with obstructive sleep apnoea: a community based study