RESUMEN
Objectives: To study the utility of aquagenic wrinkling asscreening test for children with cystic fibrosis.Design: Evaluation of diagnostic test.Setting: Pediatric Chest Clinic, and Pediatric Wards of a tertiarycare hospital in New Delhi.Participants: Three groups (children with cystic fibrosis,carriers of cystic fibrosis, and controls).Method: Time taken to develop aquagenic wrinkling wasmeasured. The test was performed by asking the enrolled subjectto put their one hand in water and was checked for development ofwrinkling every minute, and a photograph was also taken everyminute.Results: A total of 64 children with cystic fibrosis, 64 controls and64 carriers were enrolled in the study. Median (IQR) time todevelop aquagenic wrinkling in the three groups was 2 (1.5,3)minutes, 4 (3,5) minutes and 8 (5,11) minutes, respectively. Theoptimal cut-off was calculated as 3 minutes by Receiveroperating characteristic curve with a sensitivity and specificityfor identification of children with cystic fibrosis as 81% and 57%,respectively. The area under curve was 76.5%. The 3 minutecut-off for development of aquagenic wrinkling was applied to 54children referred for sweat test. 20 children had sweat chloridevalues of ≥60 mEq/l and diagnosed as cystic fibrosis. 15 of thesedeveloped aquagenic wrinkling at ≤3 minutes, giving a sensitivityof 75%.Conclusion: In places with no facility for sweat test, childrenwith phenotype compatible with cystic fibrosis who developaquagenic wrinkling in 3 minutes may be diagnosed as probablecystic fibrosis and referred for confirmation by sweat tes
RESUMEN
Objectives: The primary objective was to determine the association between beta-2 adrenergic receptor (ADRB2) gene polymorphism (rs1042713, c.46A>G, p.Arg16Gly) and the response to inhaled salbutamol in North Indian children aged 5 to 15 years, with mild to moderate exacerbation of asthma. Methods: This cross-sectional study was done at a tertiary-care hospital in Northern India from June 2011 to May 2013. 120 children with asthma with mild to moderate exacerbation underwent spirometry at baseline and after administration of three doses of salbutamol. An increase in FEV1 ³15% was considered as positive response. Blood samples from these children were analysed for ADRB2 polymorphism (p.Arg16Gly). 94 non-asthmatic adult controls were also studied to determine the prevalence of ADRB2 polymorphism. Results: In asthmatic children, the frequency of AA, GG, AG genotypes were 24.2%, 24.2% and 51.7% compared to 20.2%, 20.2 % and 59.6%, respectively in the non-asthmatic adults. Salbutamol responsiveness showed no correlation with the studied ADRB2 polymorphism (p= 0.55). A trend towards greater bronchodilator responsiveness amongst AA genotype, compared to GG genotype was observed (Median change in percent predicted FEV1 14.5% and 7.5%, respectively). Conclusions: No correlation was found between salbutamol responsiveness and ADRB2 genotype in Northern Indian children with asthma with mild-to moderate exacerbation.