Utility of contrast echocardiography for pulmonary arteriovenous malformation screening in pediatric hereditary hemorrhagic telangiectasia.

OBJECTIVE: To evaluate the utility of transthoracic contrast echocardiography (TTCE) as a screening tool for pulmonary arteriovenous malformations (PAVMs) in children with hereditary hemorrhagic telangiectasia (HHT). STUDY DESIGN: This was a single-center study of children who underwent baseline screening for PAVMs using both TTCE and chest computed tomography (CT) for evaluation of HHT. The CT and TTCE results were prospectively reviewed independently by 2 radiologists and 2 cardiologists blinded to the study results. RESULTS: Both intraobserver and interobserver agreement for interpreting TTCE results were excellent (κ = 0.97 and 0.92, respectively) and higher than the interobserver agreement for CT interpretation (κ = 0.75). The sensitivity and specificity of TTCE to predict PAVMs were 1 and 0.82, respectively, and the positive predictive and negative predictive values were 0.39 and 1, respectively. CONCLUSION: TTCE is a sensitive test for PAVMs in children with suspected HHT and can be a useful initial screening tool in pediatric HHT.

Longitudinal decline in lung volume in a population of children with sickle cell disease.

RATIONALE: Sickle cell disease (SCD) results in significant morbidity and mortality attributable to pulmonary complications. The pattern of lung function change across childhood in SCD is not well delineated. OBJECTIVES: To determine if the pattern of lung function in SCD differs from race-matched, predicted values across childhood, to describe that pattern of change, and to examine the effect of clinical covariates on lung function. METHODS: Lung function measurements for children with SCD, aged 8-18 years, from a single center were examined for inclusion. Mixed-model analysis was used to retrospectively review lung function in these children in comparison with those predicted by race-matched reference equations. The contribution of age, sex, Hb level, and beta-globin genotype on longitudinal changes in lung function was examined. MEASUREMENTS AND MAIN RESULTS: Children with SCD show significant decline in spirometric lung volumes across childhood that are concordant with the pattern of change in other measures of lung volume. The average decline for FEV(1) and total lung capacity is 2.93 and 2.15% predicted/year for males and 2.95 and 2.43% predicted/year for females. beta-Globin genotypes known to be associated with more severe disease showed a faster decline in lung function, whereas sex showed an inconsistent effect on lung function. CONCLUSIONS: Lung volumes in children with SCD decline with age. The pattern of decline begins in childhood, and supports a predominately restrictive defect.

Symptomatic children with hereditary hemorrhagic telangiectasia: a pediatric center experience.

OBJECTIVE: To assess the clinical and genetic characteristics of symptomatic children with hereditary hemorrhagic telangiectasia (HHT). DESIGN: Cross-sectional study. SETTING: The HHT clinics in Toronto. PARTICIPANTS: All children with symptomatic HHT treated from April 1, 1996, through December 31, 2002. INTERVENTIONS: Participants were screened for visceral arteriovenous malformations (AVMs). Molecular testing was performed in the children or their affected family members. MAIN OUTCOME MEASURES: Prevalence of epistaxis, telangiectases, pulmonary and cerebral AVMs, and genetic characteristics. RESULTS: Fourteen children presented with manifestations of HHT. Seven had cardiorespiratory symptoms related to pulmonary AVMs. Three had neurological symptoms secondary to bleeding from spinal or cerebral AVMs. Two were referred because of skin telangiectases and 2, because of multiple episodes of epistaxis. Screening results revealed a cerebral AVM in 1 of 11 neurologically asymptomatic children. Of the children without respiratory symptoms, 1 was diagnosed as having definite and 1, suspected pulmonary AVMs. Four children with pulmonary AVMs carried an endoglin gene mutation (HHT type 1), and 1 carried an activin receptor-like kinase 1 gene mutation (HHT type 2). The 2 children with spinal AVMs belong to the same HHT type 2 family. No mutation was found in 1 child with pulmonary and 1 with cerebral AVMs. CONCLUSIONS: Visceral AVMs and mucosal telangiectases are present in children with HHT and can lead to life-threatening events. Failure to identify a disease-associated mutation for each child suggests complex mutations or novel HHT genes.

Case verification of children with asthma in Ontario.

Asthma is an important chronic childhood illness. A population-based surveillance program could measure the burden of illness, but first, the validity of an administrative diagnosis of asthma must be confirmed. The objective was to evaluate the accuracy of population-based outpatient administrative data in identifying children with asthma for the purpose of on-going asthma surveillance and research. Twenty-one primary care physician (PCP) clinics in Ontario participated. Patients under 18 yr old were categorized into three diagnosis categories according to administrative data diagnosis codes: asthma, asthma-related, and non-asthma. In each PCP clinic, for each diagnosis category, 10 charts were randomly selected for abstraction. A panel of experts (blind to the code) reviewed the abstracted charts and identified them as asthma or non-asthma. The reviewers' diagnosis was considered the gold standard. The accuracy of the administrative data diagnosis coding was analyzed using the concepts of diagnostic test evaluation. Six hundred and thirty patient charts were abstracted and reviewed. Overall agreement between the diagnosis provided by expert chart review and the administrative data diagnosis code was 84.8% (p < 0.001), and was 60.2%, 94.8% and 99.5% for the asthma, asthma-related, and non-asthma categories, respectively. Additionally, the sensitivity and specificity were 91.4% and 82.9%, respectively. Agreement between the administrative data diagnosis code and the PCP chart diagnosis was 99.4% (p < 0.001). An administrative data diagnosis code of asthma is sensitive and specific for identifying asthma. By using the results of this study as a starting point, future research will create a cohort of children with asthma to be used for population-based surveillance and research.