Increased rate of respiratory symptoms in children with Down syndrome: a 2-year web-based parent-reported prospective study.

To compare the incidence of respiratory symptoms and short-term consequences between children with Down syndrome and children from the general population, we conducted a prospective parent-reported observational study. Children with Down syndrome (≤ 18 years) were included between March 2012 and June 2014. Caregivers received a baseline questionnaire with follow-up 1-2 years after inclusion. Caregivers received a weekly questionnaire about respiratory symptoms, fever, antibiotic prescriptions, doctor's visits, and consequences for school and work attendance. Children with Down syndrome were compared to a cohort of the general population ("Kind en Ziek" study) with similar weekly questionnaires. A total of 9,011 childweeks were reported for 116 participants with Down syndrome (75% response rate). The frequency of respiratory symptoms was higher in children with Down syndrome than in children from the general population (30% vs 15.2%). In addition, symptoms subsided later (around 8 vs 5 years of age). The seasonal influence was limited, both in children with Down syndrome and children from the general population. Consequences of respiratory disease were significant in children with Down syndrome compared to children from the general population, with a higher rate of doctor's visits (21.3% vs 11.8%), antibiotic prescriptions (47.8% vs 26.3%), and absenteeism from school (55.5% vs 25.4%) and work (parents, 9.4% vs 8.1%).  Conclusion: Children with Down syndrome have a higher frequency of respiratory symptoms and symptoms last until a later age, confirming the impression of professionals and caregivers. Individualized treatment plans might prevent unfavorable consequences of chronic recurrent respiratory disease in children with Down syndrome. What is Known: • Children with Down syndrome have an altered immune system and are prone to a more severe course of respiratory tract infections. • The overall conception is that patients with Down syndrome suffer from respiratory tract infections more often. What is New: • Children with Down syndrome suffer from respiratory symptoms more frequently than children from the general population. • The respiratory symptoms in children with Down syndrome subside at a later age compared to children from the general population.

Respiratory Symptoms in Post-infancy Children. A Dutch Pediatric Cohort Study.

Aim: To study the pattern of respiratory symptoms in children in the general population. Method: We followed a cohort of children for up to 2 years through parents completing weekly online questionnaires in the Child-Is-Ill study ("Kind-en-Ziekmeting" in Dutch); the study was running 2012-2015. Inclusion criteria were "an ordinary child" (according to the parents) and <18 years old at inclusion. We especially encouraged participation of post-infancy children. Age at inclusion, sex, smoking exposure, allergy in the family, and frequent infections in the family were noted. Pearson's correlation, principal component analysis, latent class analysis, latent profile analysis, linear regression, and linear mixed effects regression were used in the statistical analyses. Results: Data were collected on 55,524 childweeks in 755 children (50% girls; median age, 7 years; interquartile range, 4-11 years, 97% ≥2 years at inclusion), with reported symptom(s) in 8,425 childweeks (15%), leading to school absenteeism in 25%, doctor's visits in 12%, and parental sick leave in 8%; symptoms lasting ≥3 weeks were rare (2% of episodes). Linear mixed effects regression showed significant, but only limited, effects of season on the proportion of "symptom(s) reported" per individual child. Only runny nose showed a significant, but very small, age effect. However, the variability between the children was considerable. There were no obvious subgroups of children with specific symptom combinations. Conclusion: In any randomly chosen week, the vast majority of children (85%) in our-mainly-post-infancy cohort derived from the general population did not have any symptom, even in the younger age group, even in winter. The children showed considerable variability; no clear subgroups of symptom patterns could be identified, underlining the difficult position of healthcare providers. These results support our opinion that post-infancy children in the general population should not be evaluated as if they are infants when they have recurrent respiratory symptoms. If they clearly deviate from the above-described most common pattern, it is wise to keep an eye on potential, maybe even rare, serious underlying causes.

Challenges in investigating patients with isolated decreased serum IgM: The SIMcal study.

The clinical consequences of isolated decreased serum immunoglobulin (Ig)M are not sufficiently known. Therefore, it is difficult to determine the clinical policy following such a finding. Only few reported IgM-deficient patients fulfil the European Society for Immunodeficiencies (ESID) diagnostic criteria for selective IgM deficiency (true sIgMdef), or their diagnosis is uncertain due to insufficient laboratory data (possible sIgMdef). Decreased serum IgM is often incidentally found in asymptomatic adults. The objective of our study was to further characterize true sIgMdef and to compare the European data collected through the ESID Registry community (tertiary centres) to our previously published Dutch cohort (secondary centre). Fifteen centres (12 countries) participated with 98 patients. Patients were excluded if serum IgM was only determined once (n = 14), had normalized (n = 8), or if they also had other immunological abnormalities (n = 15). Ten patients (5 adults) completely fulfilled the ESID criteria for true sIgMdef. Age-matched cut-off values varied widely between centres; when using the ESID diagnostic protocol reference values, only six patients (five adults) had true sIgMdef. Because of these small numbers, further analyses were performed in patients with true or possible sIgMdef (13 adults, 48 children). Respiratory infections were commonly reported at presentation (adults 54%, children 60%). Symptomatic adults had lower serum IgM levels (mean 0.27 g/L, 95% CI 0.22-0.31) than those without symptoms (mean 0.33 g/L, 95% CI 0.30-0.36; P = 0.02). To be able to explore the clinical consequences of true sIgMdef, we should fully analyse and accurately describe those patients in whom a decreased serum IgM is found.

The Challenge of Immunoglobulin-G Subclass Deficiency and Specific Polysaccharide Antibody Deficiency--a Dutch Pediatric Cohort Study.

PURPOSE: Immunoglobulin(Ig)G-subclass deficiency and specific polysaccharide antibody deficiency (SPAD) are among the most frequent causes of recurrent respiratory infections in children. Little is known about their prevalence, clinical presentation and prognosis. No study has been published in a Western-European nor in a mainly non-tertiary cohort until now. Therefore, we performed this observational cohort study in children recruited from secondary and tertiary pediatric practices all over The Netherlands. METHODS: Dutch pediatricians were monthly asked to report patients with IgG-subclass deficiency and/or SPAD. Demographic, clinical and laboratory characteristics were collected. Separate informed consent was asked from parents and children (≥ 12 years of age) for annual update of the medical status. RESULTS: 49 children with confirmed IgG-subclass deficiency and/or SPAD were included. The majority of children (69%) was reported by four (out of 12) secondary hospitals with a pediatric immunologist in the staff. 45 children had ≥ 1 low IgG-subclass level and 11 had SPAD. IgG2 deficiency was the most prevalent IgG-subclass deficiency (37/49;76%). 10% of these children already showed bronchiectasis. Two-thirds were male (33/49;67%, p = 0.015). From 10 years of age, only boys were left and only boys showed progressive immunodeficiency during follow-up (11/24; 46%). CONCLUSIONS: This is the first Western-European mainly non-tertiary cohort of children with IgG-subclass deficiency and/or SPAD. The disease course is not always benign, especially in boys. Most children were reported and managed in secondary hospitals with a pediatric immunologist in the staff. To identify more patients, the awareness of these diseases among general pediatricians should increase.

The Gender Gap in Second Language Acquisition: Gender Differences in the Acquisition of Dutch among Immigrants from 88 Countries with 49 Mother Tongues.

Gender differences were analyzed across countries of origin and continents, and across mother tongues and language families, using a large-scale database, containing information on 27,119 adult learners of Dutch as a second language. Female learners consistently outperformed male learners in speaking and writing proficiency in Dutch as a second language. This gender gap remained remarkably robust and constant when other learner characteristics were taken into account, such as education, age of arrival, length of residence and hours studying Dutch. For reading and listening skills in Dutch, no gender gap was found. In addition, we found a general gender by education effect for all four language skills in Dutch for speaking, writing, reading, and listening. Female language learners turned out to profit more from higher educational training than male learners do in adult second language acquisition. These findings do not seem to match nurture-oriented explanatory frameworks based for instance on a human capital approach or gender-specific acculturation processes. Rather, they seem to corroborate a nature-based, gene-environment correlational framework in which language proficiency being a genetically-influenced ability interacting with environmental factors such as motivation, orientation, education, and learner strategies that still mediate between endowment and acquiring language proficiency at an adult stage.

Epidemiology of respiratory symptoms in children with Down syndrome: a nationwide prospective web-based parent-reported study.

BACKGROUND: Children with Down syndrome suffer from recurrent respiratory tract and ear-nose-throat complaints that influence daily life. Little is known about the frequency of these complaints, as well as their relation to co-morbidity and ageing. METHODS/DESIGN: A prospective web-based parent-reported observational study was designed for parents having a child with Down syndrome (age 0 to 18 years). Upon registration, parents receive an email containing a link to a weekly questionnaire regarding respiratory symptoms during two consecutive years. Additionally, at the beginning, after one year and at the end of the study they receive an extended questionnaire concerning baseline data, daily activities and medical history. The data will be compared to the ongoing "child-is-ill" study, which collects weekly data in an identical fashion in children that are considered to be "normal as to being ill" by their parents. DISCUSSION: This study will provide important data on the epidemiology of respiratory symptoms in children with Down syndrome, which will be useful for further studies on treatment options. Also, this study will gain insight in healthcare usage and work absence due to the child's illnesses.

Pediatric acute Q fever mimics other common childhood illnesses.

Knowledge of Q fever has increased over the last decades, but research has mainly focused on adults. Data in children are scarce, and current knowledge is mostly based on case reports. The aim of this study was to determine predictors for acute Q fever in children in the general population. We retrospectively studied all children tested for Coxiella burnetii by serology and/or PCR upon request of their general practitioner in the regional laboratory for Medical Microbiology of the Jeroen Bosch during the Q fever outbreak in the Netherlands between 2007 and 2011. A total of 1061 patients was analyzed. Influenza-like illness and respiratory tract infection were the most common presentations of acute Q fever, mimicking other common childhood illnesses. None of the reported symptoms was significantly related to a positive test outcome and therefore presenting signs or symptoms have no predictive value in diagnosing Q-fever in children. Only diagnostic tests are reliable. As the infection generally follows a mild and uncomplicated course, we question if the difficulty of recognizing pediatric Q fever is a problem worth solving.