Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors
Search in posts
Search in pages
Filter by Categories
15th National Conference of the IAOMFP, Chennai, 2006
Abstract
Abstracts from current literature
Acne in India: Guidelines for management - IAA Consensus Document
Addendum
Announcement
Art & Psychiatry
Article
Articles
Association Activities
Association Notes
Award Article
Book Review
Brief Report
Case Analysis
Case Letter
Case Letters
Case Notes
Case Report
Case Reports
Clinical and Laboratory Investigations
Clinical Article
Clinical Studies
Clinical Study
Commentary
Conference Oration
Conference Summary
Continuing Medical Education
Correspondence
Corrigendum
Cosmetic Dermatology
Cosmetology
Current Best Evidence
Current Issue
Current View
Derma Quest
Dermato Surgery
Dermatopathology
Dermatosurgery Specials
Dispensing Pearl
Do you know?
Drug Dialogues
e-IJDVL
Editor Speaks
Editorial
Editorial Remarks
Editorial Report
Editorial Report - 2007
Editorial report for 2004-2005
Errata
Erratum
Focus
Fourth All India Conference Programme
From Our Book Shelf
From the Desk of Chief Editor
General
Get Set for Net
Get set for the net
Guest Article
Guest Editorial
History
How I Manage?
IADVL Announcement
IADVL Announcements
IJDVL Awards
IJDVL AWARDS 2015
IJDVL Awards 2018
IJDVL Awards 2019
IJDVL Awards 2020
IJDVL International Awards 2018
Images in Clinical Practice
Images in Dermatology
In Memorium
Inaugural Address
Index
Knowledge From World Contemporaries
Leprosy Section
Letter in Response to Previous Publication
Letter to Editor
Letter to the Editor
Letter to the Editor - Case Letter
Letter to the Editor - Letter in Response to Published Article
LETTER TO THE EDITOR - LETTERS IN RESPONSE TO PUBLISHED ARTICLES
Letter to the Editor - Observation Letter
Letter to the Editor - Study Letter
Letter to the Editor - Therapy Letter
Letter to the Editor: Articles in Response to Previously Published Articles
Letters in Response to Previous Publication
Letters to the Editor
Letters to the Editor - Letter in Response to Previously Published Articles
Letters to the Editor: Case Letters
Letters to the Editor: Letters in Response to Previously Published Articles
Media and news
Medicolegal Window
Messages
Miscellaneous Letter
Musings
Net Case
Net case report
Net Image
Net Images
Net Letter
Net Quiz
Net Study
New Preparations
News
News & Views
Obituary
Observation Letter
Observation Letters
Oration
Original Article
ORIGINAL CONTRIBUTION
Original Contributions
Pattern of Skin Diseases
Pearls
Pediatric Dermatology
Pediatric Rounds
Perspective
Presedential Address
Presidential Address
Presidents Remarks
Quiz
Recommendations
Regret
Report
Report of chief editor
Report of Hon : Treasurer IADVL
Report of Hon. General Secretary IADVL
Research Methdology
Research Methodology
Resident page
Resident's Page
Resident’s Page
Residents' Corner
Residents' Corner
Residents' Page
Retraction
Review
Review Article
Review Articles
Reviewers 2022
Revision Corner
Self Assessment Programme
SEMINAR
Seminar: Chronic Arsenicosis in India
Seminar: HIV Infection
Short Communication
Short Communications
Short Report
Snippets
Special Article
Specialty Interface
Studies
Study Letter
Study Letters
Supplement-Photoprotection
Supplement-Psoriasis
Symposium - Contact Dermatitis
Symposium - Lasers
Symposium - Pediatric Dermatoses
Symposium - Psoriasis
Symposium - Vesicobullous Disorders
SYMPOSIUM - VITILIGO
Symposium Aesthetic Surgery
Symposium Dermatopathology
Symposium-Hair Disorders
Symposium-Nails Part I
Symposium-Nails-Part II
Systematic Review and Meta-Analysis
Systematic Reviews and Meta-analyses
Systematic Reviews and Meta-analysis
Tables
Technology
Therapeutic Guideline-IADVL
Therapeutic Guidelines
Therapeutic Guidelines - IADVL
Therapeutics
Therapy
Therapy Letter
Therapy Letters
View Point
Viewpoint
What’s new in Dermatology
Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors
Search in posts
Search in pages
Filter by Categories
15th National Conference of the IAOMFP, Chennai, 2006
Abstract
Abstracts from current literature
Acne in India: Guidelines for management - IAA Consensus Document
Addendum
Announcement
Art & Psychiatry
Article
Articles
Association Activities
Association Notes
Award Article
Book Review
Brief Report
Case Analysis
Case Letter
Case Letters
Case Notes
Case Report
Case Reports
Clinical and Laboratory Investigations
Clinical Article
Clinical Studies
Clinical Study
Commentary
Conference Oration
Conference Summary
Continuing Medical Education
Correspondence
Corrigendum
Cosmetic Dermatology
Cosmetology
Current Best Evidence
Current Issue
Current View
Derma Quest
Dermato Surgery
Dermatopathology
Dermatosurgery Specials
Dispensing Pearl
Do you know?
Drug Dialogues
e-IJDVL
Editor Speaks
Editorial
Editorial Remarks
Editorial Report
Editorial Report - 2007
Editorial report for 2004-2005
Errata
Erratum
Focus
Fourth All India Conference Programme
From Our Book Shelf
From the Desk of Chief Editor
General
Get Set for Net
Get set for the net
Guest Article
Guest Editorial
History
How I Manage?
IADVL Announcement
IADVL Announcements
IJDVL Awards
IJDVL AWARDS 2015
IJDVL Awards 2018
IJDVL Awards 2019
IJDVL Awards 2020
IJDVL International Awards 2018
Images in Clinical Practice
Images in Dermatology
In Memorium
Inaugural Address
Index
Knowledge From World Contemporaries
Leprosy Section
Letter in Response to Previous Publication
Letter to Editor
Letter to the Editor
Letter to the Editor - Case Letter
Letter to the Editor - Letter in Response to Published Article
LETTER TO THE EDITOR - LETTERS IN RESPONSE TO PUBLISHED ARTICLES
Letter to the Editor - Observation Letter
Letter to the Editor - Study Letter
Letter to the Editor - Therapy Letter
Letter to the Editor: Articles in Response to Previously Published Articles
Letters in Response to Previous Publication
Letters to the Editor
Letters to the Editor - Letter in Response to Previously Published Articles
Letters to the Editor: Case Letters
Letters to the Editor: Letters in Response to Previously Published Articles
Media and news
Medicolegal Window
Messages
Miscellaneous Letter
Musings
Net Case
Net case report
Net Image
Net Images
Net Letter
Net Quiz
Net Study
New Preparations
News
News & Views
Obituary
Observation Letter
Observation Letters
Oration
Original Article
ORIGINAL CONTRIBUTION
Original Contributions
Pattern of Skin Diseases
Pearls
Pediatric Dermatology
Pediatric Rounds
Perspective
Presedential Address
Presidential Address
Presidents Remarks
Quiz
Recommendations
Regret
Report
Report of chief editor
Report of Hon : Treasurer IADVL
Report of Hon. General Secretary IADVL
Research Methdology
Research Methodology
Resident page
Resident's Page
Resident’s Page
Residents' Corner
Residents' Corner
Residents' Page
Retraction
Review
Review Article
Review Articles
Reviewers 2022
Revision Corner
Self Assessment Programme
SEMINAR
Seminar: Chronic Arsenicosis in India
Seminar: HIV Infection
Short Communication
Short Communications
Short Report
Snippets
Special Article
Specialty Interface
Studies
Study Letter
Study Letters
Supplement-Photoprotection
Supplement-Psoriasis
Symposium - Contact Dermatitis
Symposium - Lasers
Symposium - Pediatric Dermatoses
Symposium - Psoriasis
Symposium - Vesicobullous Disorders
SYMPOSIUM - VITILIGO
Symposium Aesthetic Surgery
Symposium Dermatopathology
Symposium-Hair Disorders
Symposium-Nails Part I
Symposium-Nails-Part II
Systematic Review and Meta-Analysis
Systematic Reviews and Meta-analyses
Systematic Reviews and Meta-analysis
Tables
Technology
Therapeutic Guideline-IADVL
Therapeutic Guidelines
Therapeutic Guidelines - IADVL
Therapeutics
Therapy
Therapy Letter
Therapy Letters
View Point
Viewpoint
What’s new in Dermatology
View/Download PDF

Translate this page into:

COMMENTARY
2014:80:4;289-290
doi: 10.4103/0378-6323.136829

A new patch test unit

Sanjeev Handa
 Department of Dermatology and Sexually Transmitted Diseases, Postgraduate Institute of Medical Education and Research, Chandigarh, India

Correspondence Address:
Sanjeev Handa
Department of Dermatology and Sexually Transmitted Diseases, Postgraduate Institute of Medical Education and Research, Chandigarh - 160 012
India
How to cite this article:
Handa S. A new patch test unit . Indian J Dermatol Venereol Leprol 2014;80:289-290
Copyright: (C)2014 Indian Journal of Dermatology, Venereology, and Leprology

Ever since Josef Jadassohn founded the technique in 1895, patch testing has formed the most important and frequently performed investigation for arriving at a diagnosis of allergic contact dermatitis. Till date, patch test reactions are considered the best proof of allergic sensitization. Patch testing involves a patch test unit and patch test material. Various patch test units commercially available are Finn chamber on Scanpor tape, square plastic chamber (Van der Bend chambers), oval plastic chamber (Epicheck), IQ chambers (Chemotechnique Diagnostic, Sweden), TRUE (thin layer rapid use epicutaneous test), and Al test system (a filter paper disc mounted on aluminized paper). In addition, a fixing tape is required which ideally should be non-occlusive, non-allergenic and non-irritant. Since none of these patch test units are manufactured in India they need to be imported and are expensive. The only patch test unit manufactured in India (by Systopic Laboratories, India) has not been compared with the other units in terms of quality and effectiveness. In this regard, an effort to devise a locally made patch test unit which conforms to international quality standards needs to be appreciated as this can go a long way in making patch testing more cost-effective and more widely used. [1]

The authors have used low density polyethylene (LDPE; 1070 LA 17) and Micropore tape in manufacturing the new unit designated "Chamber X". Due to its low cost, the choice of Micropore tape seems to be appropriate as all tapes studied were equally non-irritant with similar adhesion potential. Although much deliberation must have gone into deciding the type of material to be used for making the patch test unit, there are certain properties of LDPE which need to be highlighted. LDPE is a thermoplastic made from the free radical polymerization of monomer ethylene under high pressure. Although relatively inert at room temperatures, it can be oxidized by strong oxidizing agents and certain organic solvents (aliphatic, aromatic, and halogenated hydrocarbons). Thus, one will need to be careful when testing for contact sensitization to such agents although the clinical relevance of such an interaction needs to be studied as aluminium in Finn chambers was earlier suspected to react with cobalt and nickel in patch test allergens but this reactivity was later found to be clinically irrelevant. [2] LDPE also has poor ultra violet (UV) resistance which means allergens may remain exposed to UV light even after they have been applied to the back. It may thus make it difficult at times to differentiate between contact allergy and photo-contact allergy. Conversely, such a property may be useful while doing a photo-patch test as one need not remove the patch test unit to expose the allergen to UV light. Other patch test units which have utilized polythene in the past (Al unit although these did not use LDPE) suffered from occurrence of occasional erythema at the test site due to oxidation of polythene by UV light and oxygen, especially in patients who were already sensitized to colophony and in humid conditions. This would be especially of interest in a tropical country like India should Chamber X become commercially available. Lastly, LDPE is flammable, a property which is of importance with regard to its storage and transport.

The authors went on to compare Chamber X with Finn chamber, IQ chamber, and locally made aluminium chambers in terms of their irritant potential, contact, occlusion, and leakage. Using spectrophotometric analysis and the Draize scale, the authors found Chamber X to have better occlusive property compared to other chambers, good contact, minimal leakage and no irritation. This data indicates that Chamber X fulfils the criteria for a clinically useful patch test unit. However, in the present study, the authors do not mention the dimensions of the chamber which is an important factor in determining the number of allergens tested. The shape will also be of interest as the square shape of IQ chamber is considered to be less irritant. Chamber X should also be tested against Finn chamber, IQ chamber, and even TRUE test in the clinical setting of patch testing in patients with contact allergy to validate its utility. This is important as it has been shown that the sensitivity of various patch test units to detect contact allergy may vary. Suneja et al., while comparing the Finn chambers with TRUE test showed that the Finn chamber was superior in detecting clinically relevant allergies to fragrance mix, balsam of Peru, and thiuram mix, whereas TRUE test performed somewhat better in detecting relevant allergic reactions to nickel, neomycin, and, methylchloroisothiazolinone/methylisothiazolinone. [3]

In conclusion, the new Chamber X appears to be an exciting new development as an indigenously manufactured diagnostic patch test unit. However, it needs further rigorous testing and standardization in actual use conditions before it can be recommended as a home grown patch test kit.

References
1.
Merchant SZ, Vaidya AD, Salvi A, Joshi RS, Mohile RB. A new occlusive patch test system comparable to IQ and finn chambers. Indian J Dermatol Venereol Leprol 2014;80:291-5.
[Google Scholar]
2.
Fischer T, Maibach H. Aluminium in Finn chambers reacts with cobalt and nickel salts in patch test materials. Contact Dermat 1985;12:200-2.
[Google Scholar]
3.
Suneja T, Belsito DV. Comparative study of Finn Chambers and T.R.U.E. test methodologies in detecting the relevant allergens inducing contact dermatitis. J Am Acad Dermatol 2001;45:836-9.
[Google Scholar]

Fulltext Views
3,533

PDF downloads
1,895
Show Sections