Clinical response to varying pollen exposure in allergic rhinitis in children in The Netherlands.

BACKGROUND: Allergic rhinitis (AR) affects 10-15% of children. Symptoms in seasonal AR are influenced by pollen exposure. Pollen counts vary throughout the pollen season and therefore, symptom severity fluctuates. This study investigates the correlation between pollen concentration and symptom load in children with AR in The Netherlands. METHODS: A secondary analysis was performed in a study determining the most effective treatment for children with seasonal AR. Symptoms were measured during three months in 2013 and 2014 using a daily symptom diary. The pollen concentration was measured with a Hirst type volumetric spore trap sampler. A correlation coefficient was calculated for the correlation between the pollen concentration and the mean daily symptom score. The study protocol was approved by the medical ethical review committee of the Erasmus MC and is incorporated in the International Clinical Trials Registry Platform (EUCTR2012-001,591-11-NL). RESULTS: In 2014, the correlation coefficient for birch pollen concentration and symptom score was 0.423 (p = 0.000). The correlation coefficient for grass pollen concentration and symptom score was 0.413 (p = 0.000) and 0.655 (p = 0.000) in 2013 and 2014, respectively. A delayed correlation between the birch pollen concentration and the symptom scores was seen up to two days after the pollen measurement (0.151, p = 0.031). For grass pollen this effect lasted up to three days after the pollen measurement (0.194, p = 0.000). CONCLUSION: We found comparable correlations between symptom score and pollen concentration as found by EAACI. Birch and grass pollen have an elongated influence on symptom score of several days. This implies patients need to continue on demand medication longer after a measured pollen peak.

Incidence and Causes of Intentional Fetal or Neonatal Demise in Twin-Twin Transfusion Syndrome.

INTRODUCTION: The aim of this study is to evaluate the incidence and causes of intentional fetal and neonatal demise in twin-twin transfusion syndrome (TTTS). MATERIAL AND METHODS: All TTTS pregnancies managed at our centre between 2000 and 2014 were included. We evaluated incidence and causes of intentional fetal/neonatal demise, defined as termination of pregnancy, selective fetal reduction, or withdrawal of neonatal intensive care. RESULTS: Intentional fetal/neonatal demise occurred in 9.8% (110/1,122) of fetuses and was due to termination of pregnancy (2.2%), selective fetal reduction (4.2%), or withdrawal of neonatal intensive care (3.4%). Reasons for termination of pregnancy included complications of laser treatment (72.0%), severe fetal anomaly (20.0%), and unwanted pregnancy (8.0%). Reasons for selective fetal reduction were technical difficulties to perform laser surgery (51.1%), fetal complications (38.3%), and parental preference for fetal reduction rather than laser treatment (10.6%). Reasons for withdrawal of neonatal intensive care treatment were severe cerebral injury (47.4%), severe pulmonary complications (15.8%), birth asphyxia (5.3%), multiple complications of TTTS and/or prematurity combined (21.1%), or other (10.5%). CONCLUSIONS: Intentional fetal or neonatal demise in TTTS occurs frequently and is often due to complications after laser surgery and/or severe (cerebral) injury in affected fetuses or neonates.