Air Sampling and Analysis of Aeroallergens: Current and Future Approaches.

PURPOSE OF REVIEW: To review current air sampling instruments and analysis methods and to describe new approaches being developed. RECENT FINDINGS: Spore trap sampling with analysis by microscopy remains the most widely used methods for aeroallergen determination even though there are often long delays from sample acquisition to data availability, as well as a need for specially-trained staff for sample analysis. The use of immunoassays and molecular biology to analyze outdoor or indoor samples has expanded in recent years and has provided valuable data on allergen exposure. New automated sampling devices capture pollen, analyze, and identify pollen grains by light scattering, laser-induced fluorescence, microscopy, or holography using signal or image processing to classify the pollen in real time or near real time. Air sampling data from current methods provide valuable information on aeroallergen exposure. The automated devices in use and under development show great potential but are not ready to replace existing aeroallergen networks.

Extreme Weather Events and Asthma.

The objective of this article is to review recent literature on the implications of extreme weather events such as thunderstorms, wildfires, tropical cyclones, freshwater flooding, and temperature extremes in relationship to asthma symptoms. Several studies have shown worsening of asthma symptoms with thunderstorms, wildfires, tropical cyclones, freshwater flooding, and temperature extremes. In particular, thunderstorm asthma can be exacerbated by certain factors such as temperature, precipitation, and allergen sensitization. Therefore, it is imperative that the allergy and immunology community be aware of the health effects associated with these extreme weather events in order to educate patients and engage in mitigation strategies.

Recalcitrant Herpes Zoster Ophthalmicus in a Patient Discovered to Have Underlying Functional Natural Killer Cell Deficiency.

PURPOSE: To report the management of a patient with chronic herpes zoster ophthalmicus with previously undiagnosed natural killer cell deficiency. METHODS: A 50-year-old female presented with herpes zoster ophthalmicus that despite appropriate treatment progressed to uveitis and expansion of the lesions. Multiple attempts to wean the patient off therapeutic anti-viral medications continued to result in reoccurrence of the disease. Discovery of underlying natural killer cell deficiency prompted indefinite treatment with therapeutic anti-viral medication. RESULTS: After multiple flares of herpes zoster ophthalmicus over 3 years, seven prior to the discovery of the immunodeficiency, she developed unilateral corneal scarring on the affected side. At this time, her visual acuity was measured to be uncorrected at 20/150 with improvement to 20/25-1 with refraction. CONCLUSIONS: This case highlights the need for further immunological investigation and unconventional medical management with recurrent viral infections to prevent visual morbidity.

Joint association between ambient air pollutant mixture and pediatric asthma exacerbations.

Exposure to air pollutants is known to exacerbate asthma, with prior studies focused on associations between single pollutant exposure and asthma exacerbations. As air pollutants often exist as a complex mixture, there is a gap in understanding the association between complex air pollutant mixtures and asthma exacerbations. We evaluated the association between the air pollutant mixture (52 pollutants) and pediatric asthma exacerbations. Method: This study focused on children (age ≤ 19 years) who lived in Douglas County, Nebraska, during 2016-2019. A seasonal-scale joint association between the outdoor air pollutant mixture adjusting for potential confounders (temperature, precipitation, wind speed, and wind direction) in relation to pediatric asthma exacerbation-related emergency department (ED) visits was evaluated using the generalized weighted quantile sum (qWQS) regression with repeated holdout validation. Results: We observed associations between air pollutant mixture and pediatric asthma exacerbations during spring (lagged by 5 days), summer (lag 0-5 days), and fall (lag 1-3 days) seasons. The estimate of the joint outdoor air pollutant mixture effect was higher during the summer season (adjusted-ßWQS = 1.11, 95% confidence interval [CI]: 0.66, 1.55), followed by spring (adjusted-ßWQS = 0.40, 95% CI: 0.16, 0.62) and fall (adjusted-ßWQS = 0.20, 95% CI: 0.06, 0.33) seasons. Among the air pollutants, PM2.5, pollen, and mold contributed higher weight to the air pollutant mixture. Conclusion: There were associations between outdoor air pollutant mixture and pediatric asthma exacerbations during the spring, summer, and fall seasons. Among the 52 outdoor air pollutant metrics investigated, PM2.5, pollen (sycamore, grass, cedar), and mold (Helminthosporium, Peronospora, and Erysiphe) contributed the highest weight to the air pollutant mixture.