al. Molecular allergy diagnostics refines characterization of children sensitized to dog dander. J Allergy Clin Immunol. 2019;144:S19-S19. 2. Auge J, Vent J, Agache I, et al. EAACI Position paper on the standardization of nasal allergen challenges. Allergy. 2018;73(8):1597-1608. 3. Nopp A, Cardell LO, Johansson SG. CD-sens can be a reliable and easy-to-use complement in the diagnosis of allergic rhinitis. Int Arch Allergy Immunol. 2013;161(1):87-90. 4. Dahlen B, Nopp A, Johansson SG, Eduards M, Skedinger M, Adedoyin J. Basophil allergen threshold sensitivity, CD-sens, is a measure of allergen sensitivity in asthma. Clin Exp Allergy. 2011;41(8):1091-1097. 5. Erwin EA, Woodfolk JA, James HR, Satinover SM, Platts-Mills TA. Changes in cat specific IgE and IgG antibodies with decreased cat exposure. Ann Allergy Asthma Immunol. 2014;112(6):545-50.e1. 6. Lebel B, Bousquet J, Morel A, Chanal I, Godard P, Michel FB. Correlation between symptoms and the threshold for release of mediators in nasal secretions during nasal challenge with grass-pollen grains. J Allergy Clin Immunol 1988;82(5 Pt 1):869-877. 7. Burnett M, Wegienka G, Havstad S, et al. Relationship of dog-and cat-specific IgE and IgG4 levels to allergic symptoms on pet exposure. J Allergy Clin Immunol Pract. 2013;1(4):350-353. 8. Perzanowski MS, Ronmark E, James HR, et al. Relevance of specific IgE antibody titer to the prevalence, severity, and persistence of asthma among 19-year-olds in northern Sweden. J Allergy Clin Immunol. 2016;138(6):1582-1590.were not able to assess the association between obesity/overweight and AR over time and were therefore unable to come to any specific conclusion on the causal factors. Second, although the immune system matures at around 12 years of age, for the present analysis, we defined children as those aged <18 years, in line with most of the studies included in this meta-analysis. Thus, we strongly suggest that for the purpose of similar studies in the future, authors should define children as ≤12 years old, adolescents as 13-18 years old, and adults as >18 years old. Third, these studies show a high degree of heterogeneity, particularly due to the ascertainment of exposure, adjustment by different confounding factors, and measurement of results mainly assessed by self-reported questionnaires. Finally, as is the case for any systematic review and meta-analysis, despite a thorough literature search, some potentially relevant studies might have been missed by our search strategy. In conclusion, our results suggest that obesity/overweight may be associated with a higher risk of AR in children. Further large cohort studies designed to investigate the temporal role of obesity/overweight in AR, as well as the mechanisms by which obesity/overweight affects AR, should confirm these findings and additionally provide valuable information on targeted therapeutic interventions.

Exposure to different air pollutants has been linked to type 2 diabetes mellitus, but the evidence for the association between air pollutants and gestational diabetes mellitus (GDM) has not been systematically evaluated. We systematically retrieved relevant studies from PubMed, Embase, and the Web of Science, and performed stratified analyses and regression analyses. Thirteen studies were analyzed, comprising 1 547 154 individuals from nine retrospective studies, three prospective studies, and one case–control study. Increased exposure to particulate matter ≤2.5 µm in diameter (PM2.5) was not associated with the increased risk of GDM (adjusted OR 1.03, 95% CI 0.99 to 1.06). However, subgroup analysis showed positive correlation of PM2.5 exposure in the second trimester with an increased risk of GDM (combined OR 1.07, 95% CI 1.00 to 1.13). Among pollutants other than PM2.5, significant association between GDM and nitrogen dioxide (NO2) (OR 1.05, 95% CI 1.01 to 1.10), nitrogen oxide (NOx) (OR 1.03, 95% CI 1.01 to 1.05), and sulfur dioxide (SO2) (OR 1.09, 95% CI 1.03 to 1.15) was noted. There was no significant association between exposure to black carbon or ozone or carbon monoxide or particulate matter ≤10 µm in diameter and GDM. Thus, systematic review of existing evidence demonstrated association of exposure to NO2, NOx, and SO2, and the second trimester exposure of PM2.5 with the increased risk of GDM. Caution may be exercised while deriving conclusions from existing evidence base because of the limited number and the observational nature of studies.

Objectives: Urine neutrophil gelatinase-associated lipocalin (NGAL) was found to increase in diabetic kidney disease (DKD). However, the clinical value of urine NGAL as diagnostic indicators in DKD remains to be clarified. Methods: Relevant studies were systematically retrieved from PubMed, Embase, Web of Science, and the Cochrane Library. Stratified analyses and regression analyses were performed. Results: Fourteen studies with 1561 individuals were included in our analysis, including 1204 cross-sectional participants and 357 cohort participants. For the cross-sectional studies, the pooled sensitivity and specificity of NGAL in the diagnosis of DKD were 0.82 (95% confidence interval (CI): 0.75–0.87) and 0.81 (95% CI: 0.68–0.90), respectively. The pooled diagnostic odds ratio was 19 (95% CI: 11–33), and the overall area under the curve was 0.88 (95% CI: 0.84–0.90). For the cohort studies, the pooled sensitivity and specificity of NGAL in the diagnosis of DKD were 0.96 (95% CI: 0.91–0.98) and 0.89 (95% CI: 0.84–0.92), respectively. The overall area under the curve was 0.98, indicating good discriminative ability of NGAL as biomarkers for DKD. Conclusions: Urine NGAL, as the early diagnostic marker of DKD, might have the high diagnostic value, especially in cohort studies.