Study On Mutations Of Filaggrin Gene And Palmar Hyperlinearity In Atopic Dermatitis

Objective To analyze the clinical characteristics of children aged 0-18 years with atopic dermatitis(AD),to identify the characteristics of clinical manifestations in children with AD.Methods(1)Case collection:AD patients aged 0-18 years old were collected,record and summary the general and clinical data of all the cases.(2)Collection of specimens:Venous blood samples of AD patients with palmar hyperlinearity and children without AD,IV or other atopic diseases were collected for genomic DNA extraction and the high frequency mutations of FLG gene were tested.(3)Statistical analysis:We use SPSS 21.0 software package to statistics analysis the test result.The measurement data were expressed as mean±standard deviation(mean±SD),and the two groups were compared with the independent sample t test,the classification data were described by frequency and percentage,and chi square test was used to analyze the classification data.Results(1)1214 AD patients aged 0-18 years were collected in this study.Male accounted for 54.5% and female were 45.5%.The average age was 40.31±40.36 months,and the median age was 27 months.The average age of onset was 8.25 ± 18.58 months,and the median age of onset is 2 months.92.1% of patients had an early onset(<2 years)and 48.6% had an individual or family history of atopic disease.(2)The most common symptoms were xerosis(82.5%),followed by facial dermatitis(19.5%),palmar hyperlinearity(23.7%),food allergy(19.6%),non-specific hand/foot dermatitis(17.1%)and ichthyosis(13%).(3)The average score of SCORAD of these patients was 46.49±16.62,and 7.3% AD patients were mild,53.0% AD patients were moderate,39.7% AD patients were severe.The average SCORAD score of 288 AD patients with palmar hyperlinearity was 45.61±15.45,7.9% AD patients were mild,65.9% AD patients were moderate,26.2% AD patients were severe.(4)In this study,45.1% of 51 AD patients with palmar hyperlinearity had FLG gene high frequency mutations.There were 14 cases(27.5%)of AD children with 3321 del A mutation,9 cases(17.6%)of AD children with K4022 X mutation.2 cases were homozygous mutations,and others were heterozygous mutations.One healthy control has heterozygous K4022 X mutation.The FLG gene mutations in the AD patients with palmar hyperlinearity were associated with food allergies,ichthyosis and nonspecific hand/foot dermatitis.No other clinical phenotypes in the experimental group were associated with high frequency mutations of the FLG gene.No association was found between age,sex,severity and FLG gene in the AD patients with palmar hyperlinearity.Conclusion(1)AD patients in our outpatient department were mainly moderate to severe.(2)The most common symptoms in AD patients were xerosis,followed by facial dermatitis,palmar hyperlinearity.In this study,the mutation rate of FLG gene detected in the experimental group is 45.1%,and the mutation rate of 3321 del A and K4022 X were 27.5% and 17.6%,respectively.The mutation of FLG gene was strongly correlated with palmar hyperlinearity positive AD patients.(3)Most AD patients with palmar hyperlinearity were moderate to severe.Palmar hyperlinearity may be a clinical phenotype that is closely related to the severity of AD and a clinical feature of AD that requires early management.(4)AD patients with Palmar hyperlinearity was strongly correlated with the FLG high frequency gene(3321del A and K4022X)mutations.(5)High frequency mutations of FLG genes(3321del A and K4022X)in AD patients with Palmar hyperlinearity were associated with ichthyosis,food allergy and non-specific hand/foot dermatitis.(6)The onset age of AD patients with Palmar hyperlinearity who carries the FLG gene mutation were small,suggesting that Palmar hyperlinearity may be a risk factor for early onset.