Studies On Epidermal Nerve Fibers, Their Morphological Relationship With Langerhans Cells And The Expression Of NGF MRNA In The Lesion Of Lichen Simplex Chronicus

ObjectiveTo estimate the magnitude of psychiatric disorders in dermatological outpatientsand to identify a set of variables associated with the presence of psychiatric disorder; toobserve and quantify the intraepidermal nerve fibers and their contacts with Langerhanscells in the lesional skin of lichen simplex chronicus; to learn the expression of NGFmRNA in the lesion on epidermal of lichen simplex chronicus; To explore theneurobiology mechanism of psychodermatoses and provide reliable basis for theapplication of psychological therapies to some skin diseases.Materials and Methods1.The method of selection and standard of study populationFour hundred and eighty three adults attending the outpatient clinics ofDepartment of Dermatology, No.1 Hospital of China Medical University andDepartment of Dermatology, Hospital of Dalian Development Area on predetermineddays were chosen for according to the following criteria: 1. clear diagnoses; 2. age≥16;3. nice cooperation; 4. being able to understand well and complete the investigateditems independently; 5. having not taken any psycho-drug within a month.Among 483 patients 221 patients belong to Psychosomatic skin diseases,othersbelong to non-psychosomatic skin diseases. Besides, 220 healthy people from Hospitalof Dalian Development Area were taken as a control group (age, sex andsocio-economic class matched)2. Diagnosis standard and the methods They were given a questionnaire comprising the 12-item General HealthQuestionnaire (GHQ-12), Self-Rating Anxiety Scale(SAS) and Self-Rating DepressionScale(SDS).GHQ-12: Using a stringent cut-off threshold (≥5) for psychologic obstacleSAS: Using a stringent cut-off threshold (≥50) for AnxietySDS: Using a stringent cut-off threshold (≥50) for Depression3 SpecimenTwenty-four biopsies of lesional skin of patients with lichen simplex chronicusand 25 some other skin diseases (5 of amyloid degeneration,5 of Gibert's pityriasis,5 ofcontact dermatitis,5 of lichen striatus, 5 of keloid) (all came from Department ofDermatology, No.1 Hospital of China Medical University) 24 normal controls (from thesurgical cases of No.1 Hospital of China Medical University) were recruited in thisstudy.4.Immunohistochemical study for nerve fibers and Langerhans cells.Using LAB-SA method, double labeled immunofluorescency and confocal laserscanning microscopy were employed in the experiments.5 Real Time PCR for expression of mRNA of NGF.Real Time PCR was applied to examine the expression of mRNA of NGF in thelesional skin. Around the lesional skin of patients with lichen simplex chronicus,healthy skin specimens and some other skin diseases were served as controls.6 Statistical methodsA database was created by FoxPro after quality examination of data. Quantitativedata were showed by (?)±SD,Student's t-test was used to assess differences betweengroups for two continuous variables. Kruskal-wallis test was used to assess differencesbetween groups for multiple continuous variables allowing for unequal variances..Multiple conditional regression was used when evaluating the effect of a continuous orcategorical covariates on a dichotomous outcome. SPSS11.0 for Windows was used for statitical analysis. A 2-tailed value of P＜0.05 was taken as statistically significant.Results1.Based on the questionnaire, taking as a stringent cut-off threshold (≥5) forpsychiatric case identification with the GHQ-12, the overall prevalence of psychiatricmorbidity in 483 patients was 30.02%(145/483), normal control group was8.64%(19/220). There was statistical difference (P＜0.01) between case group andcontrol group.We found a higher prevalence of psychiatric disorders in patients withpsychodermatology (38.46%)than those of patients with non- psychodermatology.(22.90%).There was statistical difference (P＜0.01) between psychodermatologygroup and non-psychodermatology group.The prevalence of psychiatric morbidity in 36 patients with Lichen SimplexChronicus was 38.89%(14/36). There was no significant difference in psychiatricmorbidity between the patients with Lichen Simplex Chronicus and Psychosomaticskin diseases (P＞0.05), and there was significant difference in psychiatric morbiditybetween the patients with Lichen Simplex Chronicus and non-Psychosomatic skindiseases (P＜0.01).2.Taking a score of 50 as a cut-offpoint of SAS and SDS, we found Patients' SASand SDS were higher than those of Chinese norml and control group and showedsignificant statistical differences (t_anxiety=3.14, P＜0.01; t_depression=3.08, P＜0.01).The occurrence rates of anxiety and depression were 22.57%(109/483) and18.01%(87/483). normal control group was 4.55%(10/220) and 3.18%(7/220),Therewas statistical difference (P＜0.01) between case group and control group.We found ahigher prevalence of anxiety and in patients with psychodermatology) than those ofpatients with non-psychodermatology(anxiety 14.50%, depression 9.54%).Therewas statistical difference (P＜0.01) between psychodermatology group and non-psychodermatology group.in 36 patients with Lichen Simplex Chronicus theprevalence of anxiety was 33.33%(12/36)and depression was 30.56%(11/36).There was no significant difference between the patients with Lichen Simplex Chronicus and Psychosomatic skin diseases (P＞0.05), and there was significantdifference between the patients with Lichen Simplex Chronicus and non-Psychosomatic skin diseases (P＜0.01).3. GHQ-12 is close correlation with SAS,SDS,the knowledge about disease andthe classification (psychodermatology or non-psychodermatology).4.The total length of nerve fibers in lesions of lichen simplex chronicus wassignificantly longer than that in the normal controls (t=5.71, P＜0.01) and than that inthe skin around the lesions (t=6.90, P＜0.01).5.The quantity of contacts between intraepidermal nerve fibers and Langerhanscells in lesions of lichen simplex chronicus was significantly higher than that in normalcontrol (x²=46.11, P＜0.01), and also higher than that in the skin around the lesions (x²=43.91, P＜0.01).6.The expression of mRNA of NGF in the lesional skin increased more than that inthe skin around the lesions (t=3.25, P＜0.01) and also more than that in normal control (t=3.67, P＜0.01).ConclusionsOur study has depicted the situation that is actually faced by dermatologists intheir everyday practice, where they are in a unique position to recognize psychiatricmorbidity and to take appropriate measures. The study indicated that 30.02% of thepatients had different degrees of psychological problems, of which were mainly anxietyand depression. The occurrence rates of psychological problems, anxiety anddepression of patients with psychodermatology were higher than those of patients non-psychodermatology. It was indicated that nerve fiber hyperplasy in the lesional skin oflichen simplex chronicus was closely related to the increase of NGF mRNA in theirskin. The modulatory function of nervous system upon skin immune system wasfulfilled via the effect of NGF on nerve fiber hyperplasy and the change of the functionof Langerhans cells.