Respiratory viruses and atypical bacteria triggering severe asthma exacerbation in children

1. Respiratory viruses and atypical bacteria were detected in 51.0% of Hong Kong children with asthma exacerbations, which was significantly higher than the detection rate of 27.3% in children with chronic stable asthma. 2. Co-infections of two or more respiratory pathogens were more commonly found in children with asthma exacerbations (10.7%) than in patients with stable asthma (2.6%). 3. Human rhinovirus infection was a significant risk factor for asthma exacerbations. 4. There was no significant association between the severity of asthma exacerbations and respiratory viral or atypical bacterial infections. 5. Routine use of macrolide antibiotics in the treatment of childhood asthma exacerbations should be discouraged.

Natural history and predictors for progression of mild childhood obstructive sleep apnoea

AIMS

The natural history of mild childhood obstructive sleep apnoea (OSA) was examined and factors associated with disease progression were identified.

METHODS

Subjects were recruited from an epidemiological study which examined the prevalence of OSA in Chinese children aged 6-13 years. The first 56 consecutive children identified with mild OSA (apnoea-hypopnoea index 1-5) were invited for a repeat assessment 2 years after the diagnosis.

RESULTS

45 children participated in the follow-up study, in 13 of whom (29%) the OSA was found to have worsened. Compared with those in whom OSA had not worsened, the worsened OSA group had a greater increase in waist circumference, a higher prevalence of large tonsils (occupying > or =50% of the airway) at both baseline and follow-up, and a higher prevalence of habitual snoring at both baseline and follow-up. The presence of large tonsils had a positive predictive value of 53% and a negative predictive value of 83% for worsening OSA over a 2-year period. Multivariate linear regression analysis showed that the change in obstructive apnoea-hypopnoea index was associated with age at baseline (beta (SE) = -0.92 (0.34), p = 0.009), gender (male = 1; female = 0) (beta (SE) = 4.69 (1.29), p<0.001), presence of large tonsils at baseline (beta (SE) = 4.36 (1.24), p = 0.001), change in waist circumference (beta (SE) = 0.30 (0.09), p = 0.002) and persistently large tonsils (beta (SE) = 5.69 (1.36), p<0.001) over the 2-year period.

CONCLUSIONS

Mild OSA in the majority of children does not resolve spontaneously. Subjects with tonsillar hypertrophy, especially boys, should be closely monitored to allow early detection of worsening OSA. Weight control should be stressed in the management of childhood OSA.

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

BACKGROUND

Childhood obstructive sleep apnoea (OSA) is increasingly being recognised. Its effects on blood pressure (BP) elevation and hypertension are still controversial.

OBJECTIVE

To evaluate the association between OSA and ambulatory BP in children.

METHODS

Children aged 6-13 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 the obstructive apnoea-hypopnoea index (AHI) was >1, and normal controls had AHI <1 and snoring <3 nights per week. Children with OSA were subdivided into a mild group (AHI 1-5) and moderate to severe group (AHI >5).

RESULTS

306 subjects had valid sleep and daytime BP data. Children with OSA had significantly higher BP than normal healthy children during both sleep and wakefulness. 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 to 10.5)) and diastolic (OR 3.3 (95% CI 1.4 to 8.1)) hypertension. 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 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 changes in BP.

In vitro and clinical immunomodulatory effects of a novel Pentaherbs concoction for atopic dermatitis

BACKGROUND

Our group recently reported a randomized and placebo-controlled clinical trial on the efficacy of a twice-daily concoction of five herbal ingredients (Pentaherbs formulation, PHF) in treating children with atopic dermatitis (AD).

OBJECTIVES

To investigate the immunomodulatory effects that may be induced by PHF treatment.

METHODS

We investigated the effects of PHF on cytotoxicity and proliferation of phytohaemagglutinin (PHA)- and staphylococcal enterotoxin B (SEB)-stimulated peripheral blood mononuclear cells (PBMC) isolated from buffy coat of blood donors. PHF-induced immunomodulation for five inflammatory mediators in cultured PBMC was measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. The effects of a 3-month, open-label study of PHF on circulating inflammatory mediators in children with AD were also assessed.

RESULTS

PHF at up to 1 mg mL(-1) dose-dependently suppressed PBMC proliferation. The addition of PHF to cultured PBMC reduced supernatant concentrations of brain-derived neurotrophic factor (BDNF), interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha in response to PHA, and BDNF and thymus and activation-regulated chemokine (TARC) following SEB stimulation. PHF increased epithelial cell-derived neutrophil activating peptide-78 levels in culture supernatants. At the RNA level, PHF suppressed the transcription of BDNF, TARC, IFN-gamma and TNF-alpha. Twenty-eight children with AD were treated with PHF for 3 months, and their mean plasma concentrations of BDNF and TARC decreased significantly from 1798 pg mL(-1) and 824 pg mL(-1) at baseline to 1378 pg mL(-1) and 492 pg mL(-1) (P = 0.002 and 0.013, respectively) upon study completion.

CONCLUSIONS

PHF possesses in vitro and in vivo immunomodulatory properties that may mediate the clinical efficacy observed in AD treatment.

Suppression and recovery of the hypothalamic function after high-dose corticosteroid treatment in preterm infants

BACKGROUND

High-dose systemic dexamethasone is effective in facilitating extubation of ventilated infants with bronchopulmonary dysplasia. Although the suppression and recovery of pituitary-adrenal response had been assessed after corticosteroid treatment in very low birth weight infants, its effect on hypothalamic function has not been longitudinally monitored.

AIMS

This study was designed to assess the longitudinal hypothalamic response before, during and 4 weeks after a 3-week dose-tapering course of systemic dexamethasone treatment.

PATIENTS AND METHODS

Twenty very low birth weight infants had blood collected for corticotropin-releasing hormone, ACTH and cortisol measurements immediately before starting dexamethasone (week 0), after receiving the maximum dose of treatment (week 1), at the end of the 3-week course (week 3) and 4 weeks after stopping corticosteroids (week 7).

RESULTS

All circulating hormone concentrations were significantly suppressed during the treatment period at week 1 and week 3 compared with pretreatment concentrations at week 0 (p < 0.001). The recovery of pituitary function started early soon after week 1, whereas that of hypothalamus and adrenal functions started after the end of the dexamethasone course. Plasma ACTH concentration at week 7 had returned to the pretreatment level, but plasma corticotropin-releasing hormone (p < 0.05) and serum cortisol (p < 0.001) concentrations remained significantly suppressed. Partial recovery of hypothalamic and adrenal function was observed at week 7 (62 vs. 36% of their pretreatment levels, respectively).

CONCLUSION

Our findings suggest that the hypothalamic function is suppressed during systemic corticosteroid treatment but partial recovery occurs 4 weeks after stopping therapy. Even in preterm infants, the hypothalamic-pituitary-adrenal axis behaves in a similar manner as in adult subjects and the pituitary function recovers earlier than that of hypothalamus and adrenals.

Efficacy and tolerability of a Chinese herbal medicine concoction for treatment of atopic dermatitis: a randomized, double-blind, placebo-controlled study

BACKGROUND

There has been considerable interest in traditional Chinese herbal medicine (TCHM) as a treatment for atopic dermatitis (AD). A twice-daily concoction of an ancestral formula containing five herbs has been found to be beneficial in an open study.

OBJECTIVES

To assess the efficacy and tolerability of the concoction in children with AD.

METHODS

Following a 2-week run-in period, children with long-standing moderate-to-severe AD were randomized to receive a 12-week treatment with twice-daily dosing of three capsules of either TCHM or placebo. The SCORing of Atopic Dermatitis (SCORAD) score, Children's Dermatology Life Quality Index (CDLQI), allergic rhinitis score, and requirement for topical corticosteroid and oral antihistamine were assessed before and at weeks 4, 8, 12 and 16 after treatment. Adverse events, tolerability, haematological and biochemical parameters were monitored during the study.

RESULTS

Eighty-five children with AD were recruited. Over 12 weeks, the mean SCORAD score fell from 58.3 to 49.7 in the TCHM group (n = 42; P = 0.003) and from 56.9 to 46.9 in the placebo group (n = 43; P = 0.001). However, there was no significant difference in the scores at the corresponding time points between the two groups. The CDLQI in TCHM-treated patients was significantly improved compared with patients receiving placebo at the end of the 3-month treatment and 4 weeks after stopping therapy (P = 0.008 and 0.059, respectively). The total amount of topical corticosteroid used was also significantly reduced by one-third in the TCHM group (P = 0.024). No serious adverse effects were observed between the groups.

CONCLUSIONS

The TCHM concoction is efficacious in improving quality of life and reducing topical corticosteroid use in children with moderate-to-severe AD. The formulation was palatable and well tolerated.

Which aeroallergens are associated with eczema severity?

We investigated if a correlation exists between aeroallergen sensitization and the severity of eczema. Data on aeroallergen response to skin-prick testing (SPT) and disease severity of children with eczema (n = 119) were evaluated. Atopy, as defined by at least one positive response to aeroallergen skin prick testing, was found in > 90% of eczema patients. House dust mite was the most commonly sensitized aeroallergen, followed by cat fur. Dermatophagoides pteronyssinus and Dermatophagoides farinae sensitization were associated with eczema severity (present in 67% of the mild and 97% of the severe group; P = 0.001). However, there was no association between eczema severity and higher strengths of SPT response (defined as SPT > 1+ to dust mites or dust). Atopy to moulds, Bermuda grass, cockroach, cat and dog was less prevalent and was not associated with eczema severity. It is sensible to advise parents on specific avoidance strategies only in severely affected children who have a definitive history of eczema exacerbation by specific aeroallergens and who are not responsive to conventional treatment.

Exhaled nitric oxide levels are not correlated with eczema severity in Chinese children with atopic dermatitis

Asthma is a common atopic disease associated with atopic dermatitis (AD) and allergic rhinitis (AR). Exhaled nitric oxide level (eNO) has been found to be an interesting noninvasive marker of disease severity in children with asthma. However, it is uncertain if eNO may be confounded by any coexisting AD or AR. In this study, eNO in Chinese children with moderate-to-severe AD and no asthma symptoms (n = 53) was measured online by a chemiluminescence analyzer. Severity of AD was assessed using the objective SCORing-Atopic-Dermatitis score and coexisting allergic rhinitis with the Allergic-Rhinitis-Score (ARS). Patients with active symptoms of asthma or inhaled/intranasal corticosteroids were excluded. There was no difference in eNO between genders and no correlation between eNO and AD severity regardless of ARS or bronchial reactivity status. ENO appears to be a noninvasive marker whose level is independent of the two atopic diseases of AD and AR in children old enough to perform exhalation maneuver.

Waist circumference and body mass index in Chinese children: cutoff values for predicting cardiovascular risk factors

BACKGROUND

Body mass index (BMI) and waist circumference (WC) correlate with cardiovascular (CV) risk factors in childhood which track into adulthood. WC provides a measure of central obesity, which has been specifically associated with CV risk factors. Reference standards for WC, and for WC and BMI risk threshold values are not established in Chinese children.

OBJECTIVES

To construct reference percentile charts of WC, establish relationships between WC, BMI and other risk factors, and propose WC and BMI threshold values predictive of CV risk factors in Hong Kong ethnic Chinese children.

METHODS

Weight, height, waist and hip circumference were measured in 2593 (52% boys, 47% girls) randomly sampled Hong Kong school children aged 6-12 years. In 958 of these and 97 additional overweight children (n=1055), the relationships between WC, BMI, waist/hip and waist/height ratio and six age-adjusted CV risk factors (>85% percentile levels of blood pressure (BP), fasting triglycerides, low-density lipoprotein (LDL) cholesterol, glucose and insulin levels, and <15% percentile levels of high-density lipoprotein (HDL) cholesterol) were studied. Receiver-operating characteristic analysis was employed to derive optimal age-adjusted sex-specific WC and BMI thresholds for predicting these measures of risk.

RESULTS

WC percentiles were constructed. WC correlated slightly more than BMI with CV risk factors and most strongly with insulin and systolic BP, but poorly or not with LDL and glucose. Optimal WC and BMI risk thresholds for predicting four of these six CV risk factors were ca. the 85th percentiles (sensitivities approximately 0.8, specificities approximately 0.87) with age-specific cutoff values in girls/boys from approximately 57/58 to approximately 71/76 cm and 17/18 to 22/23 kg/m(2).

CONCLUSION

These are the first set of WC reference data for Chinese children. WC risk cutoff values are proposed which, despite a smaller waist in Chinese children, are similar to those reported for American children. WC percentiles may reflect population risk.

Dietary restriction and supplementation in children with atopic eczema

Issues on empirical dietary restriction or supplementation are important but inadequately studied in children with atopic eczema (AE). The dietary habits of children with AE followed at a paediatric dermatology clinic (n = 179) were compared with those without eczema (n = 78). The mothers of 53% of the patients with or without eczema did not breastfeed their children. Common food items avoided by parents whose children have moderate-to-severe AE included fish or seafood [64% vs. 32% of controls, odds ratio (OR) 3.84, 95% CI 2.12-6.95], beef (42% vs. 17%; OR = 3.57, 95% CI 1.79-7.11), eggs (34% vs. 14%; OR = 3.05, 95% CI 1.46-6.34) and cows' milk (18% vs. 4%; OR = 5.56, 95% CI 1.61-19.12); whereas their avoidance was less frequent in children with noneczematous diseases. The avoidance of these foods were often based on belief, but 66% of all AE patients who had avoided any of the above foods reported previous experience of eczema exacerbation by these items. Patients with moderate-to-severe AE were more likely to have consumed 'bird's nest' soup and traditional Chinese medicines. It is important to evaluate whether the AE patients are genuinely 'allergic' to some of these food items. Management is suboptimal if children with food allergy and severe disease continue to consume the culprit food. Conversely, avoidance of common foods in children without food allergy could result in food faddism or malnutrition.

Induced sputum inflammatory measures correlate with disease severity in children with obstructive sleep apnoea

OBJECTIVE

To establish the association between airway inflammation and severity of obstructive sleep apnoea (OSA) in children.

METHODS

Consecutive children presenting with symptoms suggestive of OSA were recruited. They completed a sleep apnoea symptom questionnaire, underwent physical examination, spirometry, sputum induction and an overnight polysomnography. Adequate sputum contained <50% squamous epithelial cells, and OSA was diagnosed if the obstructive apnoea index was >1.

RESULTS

73 children with a median (interquartile range (IQR)) age of 11.3 (10.0-13.2) years were recruited. There were 21 girls and the median body mass index of the group was 24.0 (18.0-27.0) kg/m2. The most common presenting symptoms were habitual snoring, mouth breathing and prone sleeping position. Sputum induction was successful in 43 (59%) children, of whom 14 were found to have OSA. Children with OSA had significantly greater percentage sputum neutrophil than those without OSA (18.5 (IQR 8.0-42.0) v 4 (IQR 3.0-11.3), p = 0.006). On multiple regression analysis, percentage sputum neutrophil was significantly associated with OSA (odds ratio = 1.1, p = 0.013).

CONCLUSION

Children with OSA had airway inflammation characterised by a marked increase in neutrophils. Further studies are needed to confirm these findings and to better define the downstream cellular interactions and molecular pathogenesis in childhood OSA.

Lesson from performing SCORADs in children with atopic dermatitis: Subjective symptoms do not correlate well with disease extent or intensity

BACKGROUND

Atopic dermatitis (AD) is a distressing disease associated with pruritus and sleep disturbance. It is not known how well these symptoms correlate with the extent and intensity of eczematous involvement. We evaluated whether: (i) the level of sleep loss correlates with pruritus and (ii) the level of pruritus correlates with the extent or severity of AD in children according to the SCORing Atopic Dermatitis (SCORAD) index.

METHOD

Patients with AD younger than 18 years old were recruited from the pediatric dermatology clinic of a university teaching hospital, and AD severity was evaluated by the SCORAD index.

RESULTS

One hundred and eighty-two Chinese children with AD (107 boys and 75 girls) [mean (SD) age of 9.6 (4.2) years] were recruited. Their mean (SD) overall SCORAD was 30.1 (19.2). Sleep loss was strongly correlated with pruritus (r = 0.57, P < 0.001). However, the two subjective symptoms were only weakly correlated with the objective signs (extent and intensity) of AD. The correlations between pruritus and extent and intensity were 0.42 (P < 0.001) and 0.38 (P < 0.001), respectively, and the correlations between sleep loss and extent and intensity were 0.38 (P < 0.001) and 0.34 (P < 0.001), respectively.

CONCLUSION

We speculate that the lack of a better correlation was either because pruritus and sleep loss as reported by parents were imprecise, or that mechanisms other than disease extent or severity are responsible for the pathogenesis of these subjective symptoms.

Cough frequency in children with mild asthma correlates with sputum neutrophil count

BACKGROUND

A study was undertaken to measure cough frequency in children with stable asthma using a validated monitoring device, and to assess the correlation between cough frequency and the degree and type of airway inflammation.

METHODS

Thirty six children of median age 11.5 years (interquartile range (IQR) 9-14) with stable asthma were recruited. They underwent spirometric testing, exhaled nitric oxide (eNO) measurement, sputum induction for differential cell count, and ambulatory cough monitoring for 24 hours. Coughing episodes were counted both as individual spikes and as clusters.

RESULTS

All children had mild intermittent asthma and their median forced expiratory volume in 1 second and eNO were 83.3% (IQR 81.1-97.6) and 56.1 ppb (IQR 37.4-105), respectively. The median number of cough episodes per day was 25.5 (IQR 16-42.8). Sputum induction was successful in 69% of the subjects and cough frequency was found to have a significant positive correlation with sputum neutrophil count (r = 0.833, p = 0.0001).

CONCLUSIONS

Children with stable mild asthma have increased cough frequency that might be driven by a neutrophilic inflammatory pathway.

Longer term follow up of aerobic capacity in children affected by severe acute respiratory syndrome (SARS)

BACKGROUND

A study was undertaken to investigate the aerobic capacity and pulmonary function of children 6 and 15 months after the diagnosis of severe acute respiratory syndrome (SARS).

METHODS

Thirty four patients of mean age 14.7 years completed both pulmonary function and maximal aerobic capacity tests at 6 months. All had normal clinical examination and were asymptomatic. Their exercise responses were compared with a group of healthy controls. Complete data were collected on 27 of the original 34 cases at 15 months.

RESULTS

Compared with normal controls, the patient group had significantly lower absolute and mass related peak oxygen consumption (peak V o(2) (p<0.01)), higher ventilatory equivalent for oxygen (p<0.01), lower oxygen pulse (p<0.01), and a lower oxygen uptake efficiency slope (p<0.01) at 6 months. This impairment was unexpected and out of proportion with the degree of lung function abnormality. Residual high resolution computed tomography of thorax (HRCT) abnormalities were present in 14 patients. Those with abnormal HRCT findings had significantly lower mass related peak V o(2) than subjects with normal radiology (p<0.01). Absolute and mass related peak V o(2) in the patient group remained impaired at 15 months despite normalisation of lung function in all patients.

CONCLUSIONS

The mechanism for the reduced aerobic capacity in children following SARS is not fully understood, but it is probably a consequence of impaired perfusion to the lungs at peak exercise and deconditioning.

High levels and gender difference of exhaled nitric oxide in Chinese schoolchildren

BACKGROUND

Exhaled nitric oxide (eNO) may represent a useful noninvasive marker of airway inflammation, but data on the reference population values in schoolchildren are limited. No reference eNO study in Asian children has been published.

METHODS

Levels of eNO in a sample of 531 schoolchildren aged 11-18 years recruited from five schools (three international schools) in Hong Kong were measured online by a chemiluminescence analyser according to ERS/ATS standard. Each student also completed an International Study of Asthma and Allergic disease in Childhood questionnaire.

RESULTS

Among the children without a physician's diagnosis of asthma or symptoms of wheeze, rhinitis and eczema, there were 258 Chinese and 33 Caucasians. In control Chinese children, the eNO level (median: interquantile range) was significantly higher (P<0.001) in males (17.0 parts per billion (p.p.b.); 10.7-36.6) than in females (10.8 p.p.b.; 7.8-17.6). When compared with Caucasian control males (11.6 p.p.b.; 8.2-19.3) and females (9.1 p.p.b.; 7.5-11.9), the Chinese children had significantly higher eNO levels for both males (P=0.011) and females (P=0.037). For Chinese asthmatic males, the median eNO (interquartile range) was 39.8 p.p.b. (12.5-73.8), and for asthmatic females, 18.0 (9.6-56.3). After controlling for sex in Chinese controls, eNO did not have any significant correlation with height, weight and body mass index or body surface area.

CONCLUSIONS

This study demonstrates a gender difference of eNO level in healthy Chinese schoolchildren. When compared with Caucasians, Chinese children have significantly higher eNO levels.

Limbs Anthropometry of Singleton Chinese Newborns of 28–42 Weeks’ Gestation

Abnormalities of limbs are important features of some syndromes recognizable at birth. The purpose of this study was to establish normal standards of limbs including arm length, arm circumference, upper arm length, lower arm length, leg length, thigh circumference, upper leg length, and lower leg length. 10,226 infants (5,422 males, 4,804 females) with gestation 28-42 weeks from 12 hospitals were included. The LMS method using maximum penalized likelihood was used to perform model fitting of the anthropometric centiles for these parameters. This study provided the first set of references for the limbs of the infants by gestation and gender. Racial differences were found when comparing with other populations. The parameters are useful for evaluation of morphologic disorders involving the limbs.

Clinical features associated with nasal Staphylococcus aureus colonisation in Chinese children with moderate-to-severe atopic dermatitis

INTRODUCTION

Staphylococcus aureus colonisation/infection is common in children with atopic dermatitis (AD).

MATERIALS AND METHODS

We evaluated the nasal and body swabs of Chinese children with moderate-to-severe AD as assessed using SCORing-Atopic-Dermatitis (SCORAD) score. Swabs were taken from the right nostril, 5 flexural sites (anterior neck, antecubital fossae and popliteal fossae) and the skin area most severely affected (with oozing/crusting) for bacteriologic culture.

RESULTS

Fifty-five children (30 males and 25 females) were evaluated. Moderate-to-heavy growth of S. aureus was present in 12 (22%) of the nasal swabs, and in 1 or more flexural swabs of 32 (58%) of these children. Only 7 (35%) out of the 20 patients who had swabs taken from the worst skin area had moderate-to-heavy growth of S. aureus. Significant nasal S. aureus colonisation was associated with higher total (P=0.029) and objective SCORAD scores (P=0.040), more extensive disease (P=0.025), the presence of oozing or crusting (P=0.023) and higher eosinophil counts (P=0.038). All specimens of methicillin-sensitive S. aureus were sensitive to cloxacillin and 71% to erythromycin. Methicillin-resistant S. aureus (MRSA), sensitive to vancomycin, was only isolated in 1 patient.

CONCLUSIONS

In this study, S. aureus is a principal pathogen. Cloxacillin and first-generation cephalosporins have a favourable sensitivity profile even in children with moderate and severe atopic dermatitis. The anterior nares are an important harbour for S. aureus and significant nasal S. aureus colonisation was clinically associated with more extensive lesions and the presence of oozing or crusting.

Fever, pulmonary haemorrhage, and acute renal failure in a young girl

Leptospirosis is rarely reported in children. It is easily treated with antibiotics but can be fatal if treatment is delayed. A 12-year-old girl was diagnosed with Weil syndrome, a severe form of leptospirosis, 10 days after returning from Mainland China. She presented with fever, hypotension, jaundice, and acute renal failure. She had used well water for bathing and swum in freshwater.

Reasons for new referral non-attendance at a pediatric dermatology center: a telephone survey

BACKGROUND

Non-attendance at pediatric dermatology outpatient clinics is a significant problem.

AIM

To determine the reasons and predictors for non-attendance.

METHODS

New referral non-attenders to the pediatric dermatology clinic of a university teaching hospital were contacted by telephone and reasons for non-attendance enquired about.

RESULTS

Sixty-three patients (20%) did not attend the first appointment over a 15-month study period. The mean+/-SD waiting time between attenders and non-attenders was 99+/-46 days and 113+/-41 days (p=0.029). A total of 49% of attenders and 60% of non-attenders were males. Telephone contact of non-attenders who did not schedule any re-appointment spontaneously (n=54), found that the mother was the informant in 85% of cases. Approximately 80% of informants gave one reason for non-attendance; approximately 20% gave two or more reasons. The most common reasons for non-attendance were 'skin condition already improved' (46%) and 'forgot appointment' (25%). 'Long waiting time' did not appear to be a common reason for non-attendance. There was no significant association between age of patient, urgency of booking and non-attendance.

CONCLUSIONS

We confirm that there is a significant non-attendance rate in pediatric dermatology new referrals. Many of the skin conditions reportedly resolve spontaneously. As there is no identifiable predictor for non-attendance apart from a longer waiting time, any maneuvers or interventions to improve attendance rate are unlikely to be significantly fruitful.

Trunk anthropometry of Hong Kong Chinese infants

BACKGROUND

Disturbed growth of the trunk may result in abnormal sternocostal relationship and a variety of pectus deformities.

AIMS

The purposes of this study were to establish norms of trunk anthropometry for dysmorphology identification in the newborns and to evaluate chest circumference as a predictor for low birth weight for outborn infants where weighing scales were unavailable.

STUDY DESIGN AND SUBJECTS

A total of 10,339 Chinese infants (5478 males, 4861 females) with gestation 24-42 weeks from 12 hospitals were included. The anthropometric measurements analyzed included chest circumference, inter-nipple distance, sternal length and abdominal circumference.

OUTCOME MEASURES

The LMS method using maximum penalized likelihood was used to perform model fitting of the anthropometric centiles for these physical parameters.

RESULTS

References tables of the four physical parameters for newborns were constructed. Chest circumference showed the highest correlation with birth weight (male: r = 0.866, female: r = 0.883). The cut-off points for chest circumference of 295 (male) and 299 mm (female) were the best predictor for low birth weight. There were also racial differences in these parameters. When compared with French infants, Chinese newborns had smaller chest circumference.

CONCLUSION

These physical parameters provide useful references and aid dysmorphology diagnosis in newborns of ethnic Chinese origin.

Induced sputum in childhood asthma

Asthma is characterised by variable degrees of airway obstruction, airway hyper-responsiveness, and chronic airway inflammation. Current guidelines emphasise that inhaled corticosteroid treatment is the mainstay of asthma therapy because it targets the underlying airway inflammation. It is prudent to use the lowest possible dose of inhaled corticosteroid compatible with good asthma control. In clinical practice, the use of or the reduction of inhaled corticosteroid dosage is based on symptoms and lung function, both of which have been shown to have a poor correlation with airway inflammation. The use of induced sputum as a marker of airway inflammation improves asthma monitoring and optimises treatment in adults. This review discusses the technique of sputum induction, its clinical application, and our experience of its use in asthmatic children.

Clinical and atopic parameters and airway inflammatory markers in childhood asthma: a factor analysis

BACKGROUND

Recent studies have repeatedly shown weak correlations among lung function parameters, atopy, exhaled nitric oxide level (Feno), and airway inflammatory markers, suggesting that they are non-overlapping characteristics of asthma in adults. A study was undertaken to determine, using factor analysis, whether the above features represent separate dimensions of childhood asthma.

METHODS

Clinically stable asthmatic patients aged 7-18 years underwent spirometric testing, methacholine bronchial challenge, blood sampling for atopy markers and chemokine levels (macrophage derived chemokine (MDC), thymus and activation regulated chemokine (TARC), and eotaxin), Feno, and chemokines (MDC and eotaxin) and leukotriene B(4) measurements in exhaled breath condensate (EBC).

RESULTS

The mean (SD) forced expiratory volume in 1 second (FEV1) and Feno of 92 patients were 92.1 (15.9)% predicted and 87.3 (65.7) ppb, respectively. 59% of patients received inhaled corticosteroids. Factor analysis selected four different factors, explaining 55.5% of total variance. The Kaiser-Meyer-Olkin measure of sampling adequacy was 0.587. Plasma total and specific IgE levels, peripheral blood eosinophil percentage, and Feno loaded on factor 1; plasma TARC and MDC concentrations on factor 2; MDC, eotaxin and leukotriene B4 concentrations in EBC on factor 3; and plasma eotaxin concentration together with clinical indices including body mass index and disease severity score loaded on factor 4. Post hoc factor analyses revealed similar results when outliers were excluded.

CONCLUSIONS

The results suggest that atopy related indices and airway inflammation are separate dimensions in the assessment of childhood asthma, and inflammatory markers in peripheral blood and EBC are non-overlapping factors of asthma.

Mal-Positioned Umbilical Venous Catheter Causing Liver Abscess in a Preterm Infant

Neonatal liver abscess is uncommon, carries a high mortality and is difficult to diagnose. We report an unusual case of liver abscess in a preterm infant presenting with abdominal distension and suspected gastrointestinal perforation, rather than the more usual features of fever, hepatomegaly, abdominal tenderness, right-sided pleural effusion, and leukocytosis. We discuss current treatments for neonatal liver abscess and argue that in view of the high mortality and difficulty in diagnosis, prevention should be the primary objective. We believe that mal-positioning the umbilical venous catheter in the liver substantially increases the life-threatening risk of this complication, and advocate extreme care in the placement and use of these catheters.

A case-control study of SARS versus community acquired pneumonia

The clinical, laboratory, and radiological features at presentation of 16 children (<12 years) with severe acute respiratory syndrome (SARS) and pneumonia were compared with 32 age matched patients with community acquired pneumonia for determination of predictive factors that could allow early differentiation of the two conditions. A definitive contact history was the most important predictor for SARS. Raised serum lactate dehydrogenase concentration in the presence of low neutrophil count and serum creatine phosphokinase level at presentation also indicated an increased likelihood of SARS-coronavirus infection in young children.

A survey of bathing and showering practices in children with atopic eczema

We evaluated the emollient use and bathing habits of children with atopic eczema (AE) managed at the paediatric dermatology clinic of a university teaching hospital, using children with noneczematous skin diseases as controls. Disease severity of AE in the preceding 12 months was evaluated by the Nottingham Eczema Severity Score. Three-quarters of patients with or without eczema preferred showering to bathing. Patients with AE were more likely to use bath oils than soap and to use emollients after a bath/shower. Review cases, however, were more likely to take a shower and for a longer time (10-30 min) than first-visit eczema patients. These habits did not vary with season or disease severity. Emulsifying ointment was the most commonly used agent for the bath/shower. Most patients applied emollient immediately after a bath/shower. However there were still significant proportions of AE patients who used soap (40% of first-visit vs. 27% of review cases) and who did not apply emollients after a bath/shower (25% of first-visit vs. 23% of review cases). It is important to determine whether this problem is due to inadequate patient education or whether other factors lead to poor compliance.

Normative Data of Penile Length for Term Chinese Newborns

Careful examination and assessment of penile length in the newborn is important because micropenis is associated with hypothalamic disorders. This prospective cross-sectional study was designed to establish the norm of penile length for term Hong Kong Chinese newborns. 4,628 full-term healthy male newborns were enrolled in the study. Penile length was measured from pubic ramus to the tip of the glans penis by placing the end of a straight edge ruler against the pubic ramus. A gestation-associated graph of 3rd, 10th, 25th, 50th, 75th, 90th and 97th centiles for the penile length was created. The penile length was significantly correlated with gestational age, birth weight and body length. When compared with published data for other populations, Hong Kong newborns have significantly shorter penile length. The norm of the penile length is useful in diagnostic and therapeutics for the ethnic Chinese male newborns.

Resting energy expenditure, oxygen consumption and carbon dioxide production during sleep in children with atopic dermatitis

BACKGROUND

Pruritus and scratching are cardinal symptoms of atopic dermatitis (AD). Sleep and growth may also be affected in children with moderate-to-severe AD. We evaluated whether resting energy expenditure (REE), oxygen consumption (VO2) and carbon dioxide production (VCO2) in various stages of sleep were influenced by the disease severity.

METHODS

Disease severity was evaluated by the scoring atopic dermatitis (SCORAD) index. All-night polysomnography was performed and REE, VO2 and VCO2 were measured.

RESULTS

Twenty children (13 boys and seven girls) with AD and eight controls were recruited. The median overall SCORAD for our AD patients was 36.8. The total sleep efficiency was lower in patients with severe AD than that obtained in the control group (median: 72% versus 88%; p = 0.039). When compared with mild-to-moderate disease (SCORAD40) and controls, REE, VO2 and VCO2 in patients with severe AD (SCORAD > 40) did not differ in sleep stages I and II combined, stages III and IV combined or the rapid eye movement (REM) stage. REE, VO2 and VCO2 in these sleep stages did not show significant correlation with the overall and the three components of the SCORAD scores.

CONCLUSIONS

Children with AD do not appear to have significant disturbance in their resting energy consumption, oxygen consumption and carbon dioxide production during sleep. These parameters do not appear to correlate with the symptomatology of pruritus and sleep disturbance. We speculate that deranged metabolism during sleep is unlikely in children with AD.

Brief case series: montelukast, at doses recommended for asthma treatment, reduces disease severity and increases soluble CD14 in children with atopic dermatitis

BACKGROUND

The choice of oral therapeutic agents for the treatment of atopic dermatitis (AD) in children is limited. Montelukast, a specific cysteinyl leukotriene (LT) receptor antagonist, may be useful in alleviating AD symptoms.

OBJECTIVE

To evaluate the clinical and immunological effects of montelukast in children with AD.

METHODS

After a 2-week run-in, children with AD were started on oral montelukast 5 mg once-daily for children < 12 years of age and 10 mg for older children. The clinical severity of AD as indicated by the SCORing Atopic Dermatitis (SCORAD) score, and serum soluble CD14 and urinary leukotriene E4 (LTE4) concentrations were evaluated at baseline and the end of a 3-month treatment period.

RESULTS

Four boys and three girls, with a median (range) age of 12 (3-16) years, participated in the study. The total SCORAD was reduced in five patients (by 30-84%) and remained similar in two patients. Their median (range) SCORAD scores before and after treatment were 34.7 (16.5-54.8) and 17.0 (6.9-36.9) (p = 0.046). The intensity component of SCORAD also decreased from 5 (2-10) to 3 (1-7) (p = 0.042). Serum sCD14 levels increased significantly from 5533 (4575-6452) ng/ml to 6259 (5617-8988) ng/ml (p = 0.028), whereas urinary LTE4 levels remained the same (p = 0.735).

CONCLUSIONS

Montelukast, at doses recommended for asthma treatment, resulted in over 30% reduction in the total SCORAD in some children. Treatment with montelukast may also be associated with deviation of the immune system towards the Th1-specific pathway.

Review of children hospitalised for ingestion and poisoning at a tertiary centre

INTRODUCTION

The main aim of this study is to determine the pattern of referrals of poisoning to a tertiary university hospital. The information will be used for poison prevention programme planning, and for educating and awareness promoting to the public.

MATERIALS AND METHODS

All patients (under 21 years of age) admitted to the paediatric wards between January 1997 and December 2002 with a discharge diagnosis indicating unintentional (UP) or intentional poisoning (IP) were identified through the computerised discharge information.

RESULTS

Sixty males and 98 females accounted for 161 admissions over the 6-year period. Their mean (standard deviation, SD) age was 8.2 (6.2) years. Sixty per cent of admissions involved UP. Females accounted for 47% of the UP but 86% of the IP [odds ratio of females for IP, 7.05; 95% confidence interval (CI) 2.95 to 17.28]. When compared with UP, IP patients were significantly older [mean (SD): 14.9 (1.7) versus 3.6 (3.3) years]. In 70% of the admissions, the patients ingested a single substance. Tablets and pills, especially in the IP adolescents, were more commonly ingested than syrups. The spectrum of substances ingested was vast but paracetamol, cough or cold medicines, and common adult household medications and agents accounted for the majority of medications ingested. The substances ingested were obtained at home in 81 cases (50%) and as over-the-counter medication in 33 (20%). The majority (92%) of patients presented within 24 hours of ingestion. On admission, 63% of UP and 45% of the IP were asymptomatic. No active treatment was required in 65% of patients. In IP, nearly 30% of IP who ingested paracetamol had toxic levels and received N-acteyl cysteine. A history of previous poisoning was more common and subsequent follow-up was offered to 74%.

CONCLUSION

Young boys were more at risk of unintentional ingestion whereas adolescent girls were more likely to ingest medications as a gesture of suicide. Paracetamol is a frequently ingested medicinal for which an antidote is available.

Chemokine response in children with SARS

The chemokine response of eight children with serologically confirmed severe acute respiratory syndrome (SARS) was longitudinally monitored. All had raised plasma interferon gamma inducible protein (IP-10) concentrations, which suggested an active type 1 T-helper lymphocyte mediated immune response. High circulating IP-10 levels could facilitate viral clearance and might play a role in assisting the recovery of the patients.

Fetal growth velocities in Hong Kong Chinese infants

Few studies have investigated the velocities of fetal growth. The aim of the present study was to determine the pattern of 'fetal' growth velocities in a Chinese population. The gestation-specific measurements of the body weight, body length and head circumference in a representative sample of 5,045 male and 4,484 female newborns delivered between 26 and 42 weeks of gestation at 12 hospitals in Hong Kong were obtained. Peak growth velocity occurred before 30 weeks of gestation for head circumference, at week 30 for length and at week 30 for weight. When compared with data obtained from a French population, a significant difference in the growth velocity for body weight was observed below 32 weeks between French and Chinese infants, suggesting an ethnic difference in fetal growth of this parameter.

Declining asthma prevalence in Hong Kong Chinese schoolchildren

BACKGROUND

Many studies have reported an increase in the prevalence of asthma and related atopic disorders. The lack of standardized methodologies and 'objective' measurements make reliable comparison and monitoring of trends of asthma very difficult.

METHODS

In this study, a total of 3321 schoolchildren aged 13-14 years were recruited for study using the Phase III Protocol of the International Study of Asthma and Allergic disease in Childhood (ISAAC). The results were compared with those obtained in the Phase I ISAAC study (1994-95), which used the identical and validated core questionnaires.

RESULTS

The prevalence rates of physicians' diagnosis of asthma were similar in the two surveys (11.2% and 10.2%), but the prevalence rates of wheeze (written questionnaire) in the past year have decreased from 12.4% in 1994-95 to 8.7% in 2002 (P<0.001). For the video questionnaire, all asthmatic symptoms in the preceding 12 months were significantly lower in 2002 when compared with those in 1994-95. Among the subjects with diagnosed asthma, the prevalence rates of wheeze in the past 12 months (written questionnaire) has decreased from 39.1% to 27.6% (P<0.001). The prevalence rates of having wheezing attack at least once per month (video questionnaire) has decreased from 10.5% to 5.6% (P=0.013).

CONCLUSION

Using the same standardized and validated ISAAC questionnaire, the prevalence rates of asthma symptoms in Hong Kong Chinese schoolchildren have decreased since 1994. The exact reasons for such trend remain to be explored.

Childhood obstructive sleep apnoea: an update

OBJECTIVE

To review literature on epidemiology, complications, diagnosis, and treatment of childhood obstructive sleep apnoea.

DATA SOURCE

Literature search of MEDLINE up to July 2004 using the following key words: 'obstructive sleep apnoea syndrome', 'children', 'epidemiology', 'complications', 'treatment', and 'polysomnography'.

STUDY SELECTION

Literature and data related to the aspects of childhood obstructive sleep apnoea.

DATA EXTRACTION

Relevant information and data were reviewed by the authors.

DATA SYNTHESIS

There is a paucity of normal data on childhood obstructive sleep apnoea. Varying definitions and diagnostic criteria have been used in different studies, making direct comparison difficult. However, a small-scale local study found that the prevalence and clinical features of this condition were similar to data published overseas. Increasing evidence suggests that childhood obstructive sleep apnoea is associated with cardiovascular morbidity and neurocognitive dysfunction. Overnight polysomnography has remained the gold standard for diagnosing obstructive sleep apnoea but the diagnostic criteria has not been standardised nor correlated with the long-term outcome. Surgical intervention has remained the treatment of choice, although alternative therapies are being evaluated.

CONCLUSION

Consensus on the various important aspects of childhood obstructive sleep apnoea is still limited, especially the definition, diagnosis, and long-term sequelae of this condition. Further advances can only be made with international collaborative research, using evidence-based definitions, standardised techniques, and polysomnographic criteria.

Plasma ghrelin and resistin concentrations are suppressed in infants of insulin-dependent diabetic mothers

This study aimed to investigate 1) the effect of maternal diabetes mellitus on ghrelin, resistin, leptin, and insulin in term newborns; 2) the interrelationship of these metabolic hormones in the early postnatal period; and 3) the association of the hormones with anthropometric parameters at birth. A total of 120 term newborns were prospectively enrolled and categorized into three groups: 40 were infants of nondiabetic mothers (group N), 42 were infants born to mothers with gestational diabetes on low energy dietary treatment (group D), and 38 were infants born to mothers with preexisting or severe gestational diabetes who required exogenous insulin for stabilization of blood sugar during pregnancy (group I). Plasma ghrelin and resistin were significantly lower in group I than in either group N or group D infants (P < 0.048). Plasma ghrelin and subscapular skinfold thickness were significantly higher in female than in male infants [plasma ghrelin: median (interquartile range), 3.8 (3.0-4.8) vs. 3.0 (2.4-4.0) ng/ml in females and males, respectively; P = 0.003; subscapular skinfold thickness: 4.9 (4.2-5.6) vs. 4.6 (3.9-5.2) mm; P = 0.03]. In group N, plasma ghrelin was significantly, but negatively, associated with birth weight (r = -0.31; P = 0.05) and body length (r = -0.33; P = 0.04), whereas in group I, plasma ghrelin was negatively correlated with plasma resistin (r = -0.37; P = 0.02). Plasma ghrelin and resistin are suppressed in infants of insulin-dependent diabetic mothers, suggesting that the metabolic hormonal system is probably operational in fetal and early postnatal life. A low circulating ghrelin concentration may be advantageous to these infants, because a reduction in appetite may prevent excessive weight gain postnatally and counterbalances the in utero anabolic effect of hyperinsulinism in poorly controlled diabetic mothers. The suppressive effect of insulin on resistin may partially explain the excess accumulation of adipose tissue in infants of diabetic mothers by reducing the inhibitory effect of resistin on adipogenesis. Female infants have significantly higher plasma ghrelin levels than male infants, suggesting that sexual dimorphism exists in utero. This study has also shown an association between some of the metabolic hormones in specific groups of infants and thus suggests that these hormones could have interacted in utero to regulate growth and fat storage during this critical period.

Hepatic steatosis in obese Chinese 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/m(2) (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.

Multipotent neural precursors express neural and hematopoietic factors, and enhance ex vivo expansion of cord blood CD34+ cells, colony forming units and NOD/SCID-repopulating cells in contact and noncontact cultures

In view of the possible crosstalks between hematopoiesis and neuropoiesis, we evaluated two microenvironments, murine neonatal neural cell line C17.2 and primary embryonic aorta-gonad-mesonephros (AGM) stromal cells, on the ex vivo expansion of CD34+ cells from human cord blood. In a contact culture system, C17.2 or AGM cells significantly enhanced the expansion of CD34+ cells to a panel of early and committed hematopoietic progenitor cells. In a noncontact transwell system, pre-established C17.2 cells significantly increased the expansion of total nucleated cells, CD34+ cells and multilineage colony forming cells (P<0.01). Expanded cells were infused into nonobese diabetic/severe-combined immunodeficient mice. The engraftment of human (hu)CD45+ cells in the bone marrow of these mice was consistently higher in all the 10 experiments conducted with the support of C17.2 cells when compared with those in respective control groups (11.9 vs 2.43%, P=0.03). Using RT-PCR and Southern blot analysis, we showed that AGM and C17.2 cells expressed a panel of hematopoietic, bone morphogenetic and neurotrophic factors. Our data provided the first evidence on the promoting effects of a neural progenitor cell line on hematopoiesis at a noncontact condition. The mechanism could be mediated by the expression of multilineage regulatory factors.

Surveillance of childhood diarrhoeal disease in Hong Kong, using standardized hospital discharge data

Discharge information for all Hong Kong government hospitals, which is routinely collected through the Clinical Management System (CMS), was used to assess the relative importance of all causes of diarrhoeal illness and to address the issue of under-diagnosis of rotavirus by linking discharge diagnostic codes with actual laboratory results for one hospital. Of all children less than 5 years of age hospitalized in Hong Kong in the 2-year period July 1997 to June 1999, 12,257 (11%) were discharged with a primary diarrhoea diagnosis (74% coded as non-specified, 10.4% as rotavirus, 11% as Salmonella and 5% as other viral or bacterial). Linked laboratory and discharge data for one hospital demonstrated that 15% (n = 1522) of all admissions had a primary diarrhoea diagnosis and that 40% of these had a specimen sent for rotavirus testing, of which 37% were positive. However, 46% (67/145) of children with a diagnosis of rotavirus infection had no virology result, and 69% (172/248) of positive rotavirus results were in children with no diagnosis indicating rotavirus infection. Modification of the CMS to routinely combine existing computerized laboratory data with the CMS discharge diagnoses and to develop mechanisms to enhance reliability of discharge diagnosis coding could produce a powerful resource for disease surveillance, auditing and for monitoring the impact of future vaccination and other prevention programmes.

Increased macrophage-derived chemokine in exhaled breath condensate and plasma from children with asthma

BACKGROUND

Type 2 helper T lymphocyte-specific chemokines including macrophage-derived chemokine (MDC), thymus and activation-regulated chemokine (TARC) and eotaxin are important mediators for allergic airway inflammation.

OBJECTIVE

We investigated whether these chemokines can be detected in exhaled breath condensate (EBC) and their relation to childhood asthma.

METHODS

Asthmatics recruited from paediatric clinics of a university teaching hospital were classified into intermittent asthma (IA) and persistent asthma (PA) according to Global Initiative for Asthma guidelines. EBC was collected by a disposable collection kit, whereas fractional exhaled nitric oxide (FENO) was measured by a chemiluminescence analyser. Concentrations of MDC, TARC and eotaxin in both EBC and plasma were measured using sandwich enzyme immunoassay. The intra-subject reproducibility of exhaled chemokine measurements was determined by co-efficients of variation (CV).

RESULTS

Forty-eight patients with PA, 36 children with IA and 18 controls were recruited. MDC and eotaxin were present in EBC from nearly all subjects, whereas TARC could be measured in EBC from 33 (32%) subjects only. The median MDC concentration in EBC was higher in PA (117 pg/mL) as compared with IA (106 pg/mL) and controls (105 pg/mL; P=0.003 for both). The median plasma MDC concentration in PA (648 pg/mL) was also higher than that in IA (520 pg/mL; P=0.002) and controls (490 pg/mL; P=0.008). The median plasma TARC concentration was also increased in PA as compared with IA (72 pg/mL vs. 35 pg/mL; P=0.004). MDC concentrations in EBC were lower in patients with PA who received high-dose inhaled corticosteroid (P=0.005). FENO was significantly higher in asthmatics than controls (P<0.0001), but it was not associated with chemokines in EBC or plasma. The mean (range) CV for measuring MDC, TARC and eotaxin in EBC (n=6) were 5.5 (2.0-7.2%), 8.8 (3.6-14.4%) and 5.2 (2.8-7.9%), respectively.

CONCLUSIONS

Our results suggest that MDC in EBC and MDC and TARC in plasma are increased in children with PA as compared with IA or control. MDC concentrations in EBC are suppressed in patients on high-dose inhaled corticosteroid treatment.

Effects of inhaled corticosteroids on systemic blood pressure in preterm infants

OBJECTIVE

To assess the effect of inhaled fluticasone propionate on (i) systemic blood pressure, and (ii) the need for volume expanders (crystalloids and colloids) and inotropes for blood pressure support in preterm, very low birth weight (VLBW) infants.

METHODS

Ventilated VLBW infants, less than 32 weeks of gestation, with respiratory distress syndrome were randomised to receive a 14-day course of either fluticasone propionate (500 microg/puff, 2 puffs every 12 h; n=27) or placebo (n=26) with a metered dose inhaler-spacer device. The response of treatment was assessed by comparing the use of volume expanders, inotropes, and the average and the lowest systolic, mean and diastolic blood pressures in 6 hourly epochs between the 2 groups.

RESULTS

There were no significant differences in the average or the lowest systolic, mean and diastolic blood pressures in 6 hourly epochs between the 2 groups. However, the total volume of crystalloids and colloids requirement was significantly greater in control than in treated infants (p=0.03). There was also a trend towards greater consumption of the total cumulative dose of dopamine in the control infants (p=0.10).

CONCLUSIONS

Fluticasone-treated infants required significantly less volume of crystalloids and colloids for blood pressure support compared with control infants. Further larger scale studies are required to determine whether inhaled corticosteroids could minimise the use of volume replacement therapy and inotropes in the treatment of hypotension in preterm infants in the early postnatal period.

Infection control for SARS in a tertiary paediatric centre in Hong Kong

Severe acute respiratory syndrome (SARS) is an emerging infectious disease. After the appearance of an index patient in Hong Kong in February 2003, SARS outbreaks occurred rapidly in hospitals and spread to the community. The aim of this retrospective study is to evaluate the effectiveness of a triage policy and risk-stratified infection control measures in preventing nosocomial SARS infection among paediatric healthcare workers (HCWs) at the Prince of Wales Hospital, a general hospital to which children with SARS are referred in Hong Kong. The acute paediatric wards were stratified into three areas: (1) ultra high-risk area, (2) high-risk area and (3) moderate-risk area according to different risk levels of nosocomial SARS transmission. The implementation of different levels of infection control precautions was guided by this risk stratification strategy. Between 13 March and 23 June, 38 patients with probable and suspected SARS, 90 patients with non-SARS pneumonia, and 510 patients without pneumonia were admitted into our unit. All probable SARS cases were isolated in negative-pressure rooms. Twenty-six HCWs worked in the ultra high-risk area caring for SARS patients and 88 HCWs managed non-SARS patients in other ward areas. None of the HCWs developed clinical features suggestive of SARS. In addition, there was no nosocomial spread of SARS-associated coronavirus to other patients or visitors during this period. In conclusion, stringent infection control precautions, appropriate triage and prompt isolation of potential SARS patients may have contributed to a lack of nosocomial spread and HCW acquisition of SARS in our unit.

Combined use of alcohol hand rub and gloves reduces the incidence of late onset infection in very low birthweight infants

OBJECTIVE

To assess the incidence of late onset (> 72 hours) infection and necrotising enterocolitis (NEC) in very low birthweight (VLBW) infants in two 36 month periods using two hand hygiene protocols: conventional handwashing (HW; first 36 month period); an alcohol hand rub and gloves technique (HR; second 36 month period).

METHOD

VLBW infants admitted to the neonatal intensive care unit during the period December 1993-November 1999 were eligible. A new hand hygiene protocol using alcohol handrub and gloves was introduced in December 1996. Each patient's case record was reviewed retrospectively by two independent investigators using a standard data collection form. The incidence of NEC and systemic infections, including bacterial or fungal septicaemia, meningitis, and peritonitis, in the two periods were compared.

RESULTS

The HW and HR groups contained 161 and 176 VLBW infants respectively. The incidence of late onset systemic infection decreased from 13.5 to 4.8 episodes (including NEC)/1000 patient days after introduction of the HR regimen, representing a 2.8-fold reduction. Similarly, the incidence of Gram positive, Gram negative, and fungal infections decreased 2.5-fold, 2.6-fold, and 7-fold respectively. There was also a significant reduction in the incidence of NEC in the HR group (p < 0.0001). Subgroup analysis revealed that the incidence of methicillin resistant Staphylococcus aureus (MRSA) septicaemia was significantly decreased in the second 36 month period (p = 0.048). The clinical data suggest that infants in the HW group had significantly earlier onset of sepsis (p < 0.05) and required oxygen supplementation for longer (p < 0.05) than those in the HR group. Significantly more VLBW infants were discharged from the neonatal intensive care unit without ever being infected (p < 0.0001), and also significantly fewer infants had more than one episode of infection in the HR group (p < 0.0001).

CONCLUSION

The introduction of the HR protocol was associated with a 2.8-fold reduction in the incidence of late onset systemic infection, and also a significant decrease in the incidence of MRSA septicaemia and NEC in VLBW infants. This decrease in infection rate was maintained throughout the second 36 month period.

Urinary leukotriene E4 correlates with severity of atopic dermatitis in children

Leukotriene E4 (LTE(4)) is elevated in adults with atopic dermatitis (AD). We evaluated whether urinary LTE(4) as a noninvasive marker correlates with clinical indices of disease activity in children with AD. AD patients aged 18 years or younger were eligible for inclusion in the study. Disease severity over the preceding 3 days was evaluated by the SCORing Atopic Dermatitis (SCORAD) index. Severity of AD over the past 12 months was evaluated by the Nottingham Eczema Severity Score (NESS) in Chinese. Urinary LTE(4) concentration was measured by competitive enzyme immunoassay. One hundred and twenty-six children with AD (82 boys and 44 girls) and 45 controls were recruited. The mean +/- SD urinary log-transformed LTE(4) concentration in AD patients and controls was 2.94 +/- 0.32 and 2.62 +/- 0.20 pg/mg creatinine, respectively (P < 0.0001). SCORAD significantly correlated with NESS (r = 0.681, P < 0.0001). There were significant correlations between urinary LTE(4) concentration and overall SCORAD score (r = 0.270, P = 0.002) and its extent (r = 0.185, P = 0.038) and intensity components (r = 0.247, P = 0.005), but not with NESS. When compared with mild AD, urinary LTE(4) concentrations were higher in patients with moderate-to-severe disease (P = 0.049). Urinary LTE(4) measurement is noninvasive and may be useful in supplementing the SCORAD for following longitudinal changes in AD severity in children. However, the practical value of this assay in a clinical setting remains to be determined.

Serum levels of cutaneous T-cell attracting chemokine (CTACK) as a laboratory marker of the severity of atopic dermatitis in children

There are at least 13 scoring systems for the assessment of disease severity in atopic dermatitis (AD). Each system has its problems with interobserver and intraobserver variability. Cutaneous T-cell attracting chemokine (CTACK) is a skin-specific chemoattractant which may correlate with AD severity and obviate the issue of observer reliability. We evaluated whether serum CTACK concentrations were associated with the severity of AD in children according to the SCORing Atopic Dermatitis (SCORAD) index. Thirty-seven Chinese children with AD (23 boys, 14 girls; aged 1-11 years) and 13 controls were recruited. The median (interquartile range) overall SCORAD for AD patients was 29.7 (20.3-49.7). Serum concentrations of CTACK and two other atopy-related chemokines, macrophage-derived chemokine (MDC) and thymus and activation-regulated chemokine (TARC), were measured by sandwich enzyme immunoassay. There were significant correlations between SCORAD (r = 0.394, P = 0.016), its area (r = 0.528, P = 0.001) and intensity components (r = 0.429, P = 0.008) with serum levels of CTACK. The serum concentrations of inflammatory markers MDC and TARC also correlated with the CTACK concentrations (r = 0.618, P < 0.001, and r = 0.587, P = 0.001, respectively). Serum CTACK concentration appears to be a skin-specific objective marker that correlates with various clinical and laboratory parameters of AD.

Transient adrenocortical insufficiency of prematurity and systemic hypotension in very low birthweight infants

OBJECTIVES

A proportion of preterm, very low birthweight (VLBW, < 1500 g) infants may show inadequate adrenal response to stress in the immediate postnatal period. The human corticotrophin releasing hormone (hCRH) stimulation test was used to: (a) determine the relation between pituitary-adrenal response and systemic blood pressure in these infants; (b) characterise the endocrinological features of transient adrenocortical insufficiency of prematurity (TAP).

STUDY DESIGN

A total of 226 hCRH tests were performed on 137 VLBW infants on day 7 and 14 of life in a tertiary neonatal centre.

RESULTS

Basal, peak, and incremental rise in serum cortisol (Delta Cort(0-30)) on day 7 were associated significantly with the lowest systolic, mean, and diastolic blood pressures recorded during the first two weeks of life (r > 0.25, p < 0.005). These cortisol concentrations also correlated significantly but negatively with the maximum and total cumulative dose of dopamine (r > -0.22, p < 0.02), dobutamine (r > -0.18, p < 0.04), and adrenaline (r > -0.26, p < 0.004), total volume of crystalloid (r > -0.22, p < 0.02), and duration of inotrope treatment (r > -0.25, p < 0.006). Multivariate regression analysis of significant factors showed that the lowest systolic, mean, and diastolic blood pressures remained independently associated with serum cortisol (basal, peak, and Delta Cort(0-30)) on day 7. Hypotensive infants requiring inotropes (group 2) were significantly less mature and more sick than infants with normal blood pressure (group 1). The areas under the ACTH response curves were significantly greater in group 2 than in group 1, on both day 7 (p = 0.004) and day 14 (p = 0.004). In contrast, the area under the cortisol response curve was significantly greater in group 1 than in group 2 on day 7 (p = 0.001), but there was no significant difference between the two groups on day 14. In addition, serum cortisol at the 50th centile in hypotensive infants had high specificity and positive predictive value (0.80-0.93 and 0.81-0.89 respectively) for predicting early neonatal hypotension.

CONCLUSIONS

This study characterises the fundamental endocrinological features of TAP: normal or exaggerated pituitary response; adrenocortical insufficiency; good recovery of adrenal function by day 14 of postnatal life. The results also provide the centiles of serum cortisol for hypotensive patients and infants with normal blood pressure, and show a significant relation between serum cortisol and blood pressure in VLBW infants.