Yvonne Belessis

Asthma Exacerbations in Children Associated with Rhinovirus but not Human Metapneumovirus Infection

Children with asthma were studied during the Southern hemisphere winter and summer of 2001-2002. Human rhinovirus (hRV) was significantly associated (P=.0001) with asthma exacerbations in winter and spring/summer, but not in intervening asymptomatic periods. Although hRV was also found in children with upper respiratory tract infection (URTI) who underwent sampling at the same time, it was present in significantly higher numbers of children with symptomatic asthma (P<.0001). Human metapneumovirus was also found in small numbers of children with URTI, but significantly less frequently in children with asthma.

Early Cystic Fibrosis Lung Disease Detected by Bronchoalveolar Lavage and Lung Clearance Index

RATIONALE Unrecognized airway infection and inflammation in young children with cystic fibrosis (CF) may lead to irreversible lung disease; therefore early detection and treatment is highly desirable. OBJECTIVES To determine whether the lung clearance index (LCI) is a sensitive and repeatable noninvasive measure of airway infection and inflammation in newborn-screened children with CF. METHODS Forty-seven well children with CF (mean age, 1.55 yr) and 25 healthy children (mean age, 1.26 yr) underwent multiple-breath washout testing. LCI within and between-test variability was assessed. Children with CF also had surveillance bronchoalveolar lavage performed. MEASUREMENTS AND MAIN RESULTS The mean (SD) LCI in healthy children was 6.45 (0.49). The LCI was higher in children with CF (7.21 [0.81]; P < 0.001). The upper limit of normal for the LCI was 7.41. Fifteen (32%) children with CF had an elevated LCI. LCI measurements were repeatable and reproducible. Airway infection was present in 17 (36%) children with CF, including 7 (15%) with Pseudomonas aeruginosa. Polymicrobial growth was associated with worse inflammation. The LCI was higher in children with Pseudomonas (7.92 [1.16]) than in children without Pseudomonas (7.02 [0.56]) (P = 0.038). The LCI correlated with bronchoalveolar lavage IL-8 (R(2) = 0.20, P = 0.004) and neutrophil count (R(2) = 0.21, P = 0.001). An LCI below the upper limit of normality had a high negative predictive value (93%) in excluding Pseudomonas. CONCLUSIONS The LCI is elevated early in CF, especially in the presence of Pseudomonas and airway inflammation. The LCI is a feasible, repeatable, and sensitive noninvasive marker of lung disease in young children with CF.

Early Glucose Abnormalities in Cystic Fibrosis Are Preceded by Poor Weight Gain

OBJECTIVE Progressive β-cell loss causes catabolism in cystic fibrosis. Existing diagnostic criteria for diabetes were based on microvascular complications rather than on cystic fibrosis–specific outcomes. We aimed to relate glycemic status in cystic fibrosis to weight and lung function changes. RESEARCH DESIGN AND METHODS We determined peak blood glucose (BGmax) during oral glucose tolerance tests (OGTTs) with samples every 30 min for 33 consecutive children (aged 10.2–18 years). Twenty-five also agreed to undergo continuous glucose monitoring (CGM) (Medtronic). Outcome measures were change in weight standard deviation score (wtSDS), percent forced expiratory volume in 1 s (%FEV1), and percent forced vital capacity (%FVC) in the year preceding the OGTT. RESULTS Declining wtSDS and %FVC were associated with higher BGmax (both P = 0.02) and with CGM time >7.8 mmol/l (P = 0.006 and P = 0.02, respectively) but not with BG120 min. A decline in %FEV1 was related to CGM time >7.8 mmol/l (P = 0.02). Using receiver operating characteristic (ROC) analysis to determine optimal glycemic cutoffs, CGM time above 7.8 mmol/l ≥4.5% detected declining wtSDS with 89% sensitivity and 86% specificity (area under the ROC curve 0.89, P = 0.003). BGmax ≥8.2 mmol/l gave 87% sensitivity and 70% specificity (0.76, P = 0.02). BG120 min did not detect declining wtSDS (0.59, P = 0.41). After exclusion of two patients with BG120 min ≥11.1 mmol/l, the decline in wtSDS was worse if BGmax was ≥8.2 mmol/l (−0.3 ± 0.4 vs. 0.0 ± 0.4 for BGmax <8.2 mmol/l, P = 0.04) or if CGM time above 7.8 mmol/l was ≥4.5% (−0.3 ± 0.4 vs. 0.1 ± 0.2 for time <4.5%, P = 0.01). CONCLUSIONS BGmax ≥8.2 mmol/l on an OGTT and CGM time above 7.8 mmol/l ≥4.5% are associated with declining wtSDS and lung function in the preceding 12 months.

Once daily insulin detemir in cystic fibrosis with insulin deficiency

The aim of this study was to determine if once daily insulin detemir reverses decline in weight and lung function in patients with cystic fibrosis (CF). 12 patients with early insulin deficiency and six with CF related diabetes (aged 7.2–18.1 years) were treated for a median of 0.8 years. Changes in weight and lung function following treatment were compared to pretreatment changes. Before treatment, the change in weight SD score (ΔWtSDS), percentage of predicted forced expiratory volume in 1 s (Δ%FEV1) and percentage of predicted forced vital capacity (Δ%FVC) declined in the whole study population (−0.45±0.38, −7.9±12.8%, −5.8±14.3%) and in the subgroup with early insulin deficiency (−0.41±0.43, −9.8±9.3%, −6.8±10.3%). Following treatment with insulin ΔWtSDS, Δ%FEV1 and Δ%FVC significantly improved in the whole study population (+0.18±0.29 SDS, p=0.0001; +3.7±10.6%, p=0.007; +5.2±12.7%, p=0.013) and in patients with early insulin deficiency (+0.22±0.31 SDS, p=0.003; +5.3±11.5%, p=0.004; +5.8±13.4%, p=0.024). Randomised controlled trials are now needed.

Acid and non‐acid reflux during physiotherapy in young children with cystic fibrosis

Gastro‐esophageal reflux (GOR) may contribute to lung disease in children with cystic fibrosis (CF). There is conflicting evidence regarding the effect of chest physiotherapy (CPT) in the head‐down position on GOR. Furthermore, there is currently no evidence on the impact of physiotherapy on GOR as assessed by pH‐multichannel intraluminal impedance (pH‐MII).

Expression of PPARγ and Paraoxonase 2 Correlated with Pseudomonas aeruginosa Infection in Cystic Fibrosis

The Pseudomonas aeruginosa quorum sensing signal molecule N-3-oxododecanoyl-l-homoserine lactone (3OC12HSL) can inhibit function of the mammalian anti-inflammatory transcription factor peroxisome proliferator activated receptor (PPAR)γ, and can be degraded by human paraoxonase (PON)2. Because 3OC12HSL is detected in lungs of cystic fibrosis (CF) patients infected with P. aeruginosa, we investigated the relationship between P. aeruginosa infection and gene expression of PPARγ and PON2 in bronchoalveolar lavage fluid (BALF) of children with CF. Total RNA was extracted from cell pellets of BALF from 43 children aged 6 months–5 years and analyzed by reverse transcription–quantitative real time PCR for gene expression of PPARγ, PON2, and P. aeruginosa lasI, the 3OC12HSL synthase. Patients with culture-confirmed P. aeruginosa infection had significantly lower gene expression of PPARγ and PON2 than patients without P. aeruginosa infection. All samples that were culture-positive for P. aeruginosa were also positive for lasI expression. There was no significant difference in PPARγ or PON2 expression between patients without culture-detectable infection and those with non-Pseudomonal bacterial infection, so reduced expression was specifically associated with P. aeruginosa infection. Expression of both PPARγ and PON2 was inversely correlated with neutrophil counts in BALF, but showed no correlation with other variables evaluated. Thus, lower PPARγ and PON2 gene expression in the BALF of children with CF is associated specifically with P. aeruginosa infection and neutrophilia. We cannot differentiate whether this is a cause or the effect of P. aeruginosa infection, but propose that the level of expression of these genes may be a marker for susceptibility to early acquisition of P. aeruginosa in children with CF.

Diagnostic accuracy and distress associated with oropharyngeal suction in cystic fibrosis.

BACKGROUND Early detection of bacterial pathogens in the lower airway is an important part of managing CF. This study aimed to assess the diagnostic accuracy of oropharyngeal suction (OPS) samples in obtaining airway bacterial cultures in young children with cystic fibrosis (CF), and the level of child distress caused by obtaining OPS samples. METHODS Young children with CF undergoing broncho-alveolar lavage (BAL) as part of concurrent research or routine annual surveillance were studied. OPS was performed by stimulating a cough and suctioning the back of the oropharynx in the awake child to replicate clinical practice. BAL of the right upper, middle and lingula lobes was then performed. Samples were sent for standard bacterial culture. The childs distress during OPS was rated using the Groningen Distress Scale (1=calm, 2=timid/nervous, 3=serious distress but still under control, 4=serious distress with loss of control, 5=panic). RESULTS There were 65 paired samples obtained from 39 children (21 boys, mean age on day of first sampling was 34.1months, SD 19.1months). For Pseudomonas aeruginosa, specificity, sensitivity, NPV and PPV with 95% CI were 98% (87-99), 75% (20-96), 98% (91-98) and 60% (15-93%) respectively. In all age groups combined, median level of distress was 3 (IQR 2-4), with distress highest in 2 and 3year olds, with a median of 4 (IQR 3-4). CONCLUSION OPS has diagnostic utility in determining the absence of organisms in the lower airway, with specificity for P.aeruginosa detection of 98%. However, a positive OPS result is not necessarily a good indicator of lower airway infection. Distress levels were high during OPS, mostly in 2 and 3year olds.

Prevalence of Malnutrition and Feeding Difficulties in Children With Esophageal Atresia.

Objectives: Growth and feeding problems have been described in children with esophageal atresia (EA). Ongoing gastrointestinal and respiratory complications such as Gastroesophageal reflux disease, esophageal dysmotility, strictures, and respiratory infections may contribute. The aim of the study was to document the prevalence of malnutrition and feeding difficulties and examine predictive factors, which may influence feeding and growth in children attending a multidisciplinary EA clinic in Sydney, Australia. Methods: A retrospective review of 75 children, ages 0 to 16 years, who attended a multidisciplinary EA clinic between 2011 and 2014. Data on demographics, comorbidities, nutrition, and mealtime behaviors were collected from their initial clinic appointment. Factors that may affect on growth and mealtime behaviors were identified and analyzed. Results: Nine percent of children were malnourished and 9% were stunted. Infants, children with prior fundoplication, at risk of aspiration, or those who had surgery in the first year of life additional to EA repair were significantly more likely to be malnourished (P < 0.05). Fifty-four percent of children required texture modification at their meals, with parental concern being the most common reason. Younger children were less likely to be eating age-appropriate textures (P = 0.04) which improved after 5 years of age. Conclusions: Poor growth and inability to manage age-appropriate textures are often present in children with EA, particularly in the younger years. This highlights the need for early intervention in a specialist multidisciplinary EA clinic in which dietetics and speech pathology are available.

Age-related levels of fecal M2-pyruvate kinase in children with cystic fibrosis and healthy children 0 to 10 years old

BACKGROUND The pathogenesis of gut inflammation, bacterial dysbiosis and increased rates of malignancy in CF is unclear. Fecal M2-pyruvate kinase (M2-PK) is a biomarker indicative of cellular proliferation that may be raised in intestinal malignancy and inflammation. Biomarkers, including M2-PK, may be useful in assessing effects of novel therapies on the gastrointestinal tract. METHODS M2-PK was measured in stools collected from patients with CF and HC (0-10years). Linear mixed model analysis was used. RESULTS M2-PK levels did not significantly change in children with CF (36 patients, 77 samples) (P=0.998) or HC (45 patients, 45 samples) (P=0.21), over the age range 0-10years. Patients with CF had elevated M2-PK compared to HC (median [IQR; range]: 10.7 [5.7-28.6; 1.0-239.1] (n=77) vs. 1.0 [1.0-1.0; 1.0-50.0] (n=45) U/mL, respectively; P=0.001). CONCLUSIONS Fecal M2-PK was elevated in children with CF compared with HC during infancy and throughout childhood suggesting abnormalities in the CF gut exist in early life.

Absence of back to school peaks in human rhinovirus detections and respiratory symptoms in a cohort of children with asthma

Much of what is known about the seasonality of human rhinovirus (hRV) infections has been learned from the study of acute asthma exacerbations presenting to emergency care, including those among children at the start of the school term. Much less is known about the patterns of hRVs in the community. In this study, viruses and day‐to‐day symptoms of asthma and colds were monitored twice weekly in 67 children with asthma aged 5–12 years, over a 15 month period in Sydney, Australia. Overall hRV was detected in 314/1232 (25.5%) of nasal wash samples and 142/1231 (11.5%) of exhaled breath samples; of these, 231 and 24 respectively were genotyped. HRVs were detected with similar prevalence rate throughout the year, including no peak in hRV prevalence following return to school. No peaks were seen in asthma and cold symptoms using twice‐weekly diary records. However, over the same period in the community, there were peaks in asthma emergency visits both at a large local hospital and in state‐wide hospitalizations, following both return to school (February) and in late autumn (May) in children of the same age. This study suggests that hRV infections are common throughout the year among children, and differences in virus prevalence alone may not account for peaks in asthma symptoms. J. Med. Virol. 88:578–587, 2016.