Common Contact Sensitizers among Patients with Hand Eczema : A Multicenter-Study in Nepal

Introduction: Allergic contact dermatitis in Nepal is not an uncommon disorder. Patch testing is a well established method of diagnosing allergic contact dermatitis. Patients with contact dermatitis are well known to have impaired quality of life which often leads to frequent dermatological consultations. Objective: Lack of data from Nepal has prompted us to undertake this study with the aims to know the frequency of allergic contact dermatitis and the commonest contact allergens among the patients with Hand eczema attending the out-patient department of dermatology, B.P. Koirala Institute of Health Sciences and Kathmandu Medical College Teaching Hospital. Material and Methods: A total of 256 patients were included in the study. Out of them 195 with hand eczema agreed to participate and undergo patch testing. The antigens used included the Indian standard series of patch test allergens approved by Contact and Occupational Dermatoses Forum of India. Results: Hundred and ten cases (56.4%) were patch test positive (PTP) at 48 as well as 96 hours to at least one allergen. PTP was seen more commonly in females. The most common allergen in females was nickel sulphate followed by cobalt chloride, gentamicin and mercapto mix while males were positive to potassium dichromate, followed by epoxy resin, fragrance mix and nickel sulphate. Conclusion: Patch testing has proved a useful tool for the detection of allergic contact dermatitis and for identification of contact allergens. When positive reactions correlate with environmental exposure the test usually assists the physician in establishing the cause of dermatitis, hence treating the patients and improving their quality of life.


Introduction
T he term hand eczema (HE) implies when the derma s is largely confi ned to the hands with only minor involvement of the other areas.The condi on has been described as a chronic disabling and distressing condi on both for the physicians and pa ents alike.The reported prevalence of HE in the general popula on is es mated to be about 2-10% 1,2 and it accounts for 21-35% of all types of eczema. 3e pathogenesis of hand eczema is mul factorial, with contribu on of internal factors such as an atopic status and external factors, such as allergens and irritants.The precise impact of allergic contact derma s remains unclear, although pa ents o en suspect an allergy and recently published guidelines stress the importance of patch tes ng. 4,5ere are no standard series of patch test allergens in Nepal and our objec ve in this study is aimed at iden fying common allergens responsible for allergic contact derma s among hand eczema pa ents in the general Nepalese popula on using the Indian Standard baseline series.Other skin diseases involving the hand, such as infec ve derma s, dermatophy de, eczematous drug reac ons, psoriasis and cumula ve insult derma s were excluded by history and clinical examina on.

Patients
A detailed history of each pa ent was recorded in the proforma designed for the study which was approved by the ins tu onal review board and the ethical commi ee.

Patch test
Patch test was done in all pa ents of hand eczema using the Indian Standard Series of Allergens as approved by the Contact and Occupa onal Dermatoses Forum of India (CODFI), consis ng of 28 allergens Finn chambers were used and allergens, usually incorporated in petrolatum, were applied in round chambers of inert material (aluminum, polyethylene), which were mounted on adhesive tapes free from colophony.
Patch tests were applied on the upper half of the back a er cleaning the area with spirit and the results were recorded at 48 hours and 96 hours.

Statistical analysis
Data was tabulated and interpreted in terms of percentage, mean and standard devia on in the computer using SPSS version 20.To test the signifi cance of associa on Chi square test was applied.

Results
Total 256 pa ents with hand eczema were approached.Out of them 195 agreed to par cipate in the study and took patch tes ng.Out of 195 pa ents, 117 were females and remaining 78 were males, for a gender ra o of 1.5:1.The mean age of the respondents was 32 years ± 14.5 years.The age varied within a wide range of 15 years to 70 years.Dura on of disease at the me of presenta on of respondents was found to range from minimum 1 week to maximum 15 years.Out of 195 cases who had done patch tes ng, 110 cases (56.4%) showed posi ve reac on in patch tes ng to at least one allergen.
Table 1 shows the common posi ve tested allergens in all pa ents with hand eczema.The most frequent sensi zer was Nickel sulphate (22.7%).Subsequently, Gentamicin, Fragrance mix, Epoxy resin and Potassium dichromate caused a substan al amount of posi ve reac ons.
Table 2 displays the distribu on of posi ve patch test reac on by sex.Females had more sensi zer for Nickel, and Gentamicin whereas males had more sensi zer for Fragrance mix, Epoxy resin and Potassium dichromate but these were not sta s cally signifi cant.Overall, the most frequent sensi zer did not deviate between the two study centers.

Discussion
An es mated 2-10% of popula on is likely to develop hand eczema at some point of me during life.In addi on, 20-35% of all derma s aff ects the hands.It appears to be the most common occupa onal skin disease, comprising 9-35% of all occupa onal disease and up to 80% or more of all occupa onal contact derma s. 7 The ae ology of hand eczema is a complex combined eff ect of major causes and other factors, where the degree of infl uence of each factor is impossible to determine.The most common cause however s ll appears to be the exogenous cause.
Allergic contact sensi za on is known to be influenced by environmental, cultural, occupa onal, individual, gene c and racial or ethnic factors.Patch Tes ng has been proven to establish a posi ve role in iden fying the contact allergens in hand eczema pa ents suspected of having an allergic e ology.9][10][11][12] Nickel is a well-known sensi zer and various eff orts have been made to reduce the number of sensi za ons in the general popula on.3][14][15] Nickel posi vity has shown a female preponderance in our study as reported by Bilcha et al 15 and Bilcha et al 16 .The higher rates of posi ve patch test reac ons for nickel sulfate in females could relate to their ear piercing, cosme c applica on and ornament use behavior.
Gentamicin was the next common sensi zer seen in our pa ents (15.5%) with a similar female preponderance.This could be explained by the se ng of the study popula on where female nurses coming for visits were more frequent and the easy availaibility of the medica on for minor skin lesions.
The third, fourth and the fi h common an gen in our study was found to be in fragrance mix in 16 (14.5%),epoxy resin 14 (12.7%) and potassium dichromate in 12 (11.0%)pa ents respec vely with a slightly higher male preponderance.Construc on work is one among the most important occupa ons predisposing to allergic contact derma s 17 and is most commonly because of potassium dichromate. 18,19This is shown in our study by higher rates of posi ve reac ons to potassium dichromate in cement workers and in subjects with hand derma s as reported in the literature. 20

Conclusions
Nickel, Gentamicin, Fragrance mix, Epoxy resin and Potassium dichromate are common sensi zers in pa ents with Hand eczema in Nepal.Thus, the iden fi ca on and evalua on of risk factors for the development and persistence of hand eczema are important to prevent the morbidity of pa ents and to improve their quality of life.
This was a hospital based descrip ve study in which all clinically diagnosed cases of hand eczema a ending the Dermatology Out Pa ent Department of B. P. Koirala Ins tute of Health Sciences, Dharan over May 2009 -June 2012 and the Out Pa ent Department July 2012-June 2015, Kathmandu Medical College, cons tuted the study popula on.

Table 2 :
Gender-wise distribu on of patch posi ve cases (n=110)