|LETTERS TO THE EDITOR - LETTER IN RESPONSE TO PREVIOUSLY PUBLISHED ARTICLES
|Year : 2019 | Volume
| Issue : 1 | Page : 81-82
Intramatricial injections for nail psoriasis: An open-label comparative study of triamcinolone, methotrexate, and cyclosporine
Surya Ravindran, Sebastian Criton
Department of Dermatology, Amala Institute of Medical Sciences, Thrissur, Kerala, India
|Date of Web Publication||20-Nov-2018|
Dr. Surya Ravindran
Department of Dermatology, Amala Institute of Medical Sciences, Amala Nagar, Thrissur - 680 555, Kerala
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Ravindran S, Criton S. Intramatricial injections for nail psoriasis: An open-label comparative study of triamcinolone, methotrexate, and cyclosporine. Indian J Dermatol Venereol Leprol 2019;85:81-2
|How to cite this URL:|
Ravindran S, Criton S. Intramatricial injections for nail psoriasis: An open-label comparative study of triamcinolone, methotrexate, and cyclosporine. Indian J Dermatol Venereol Leprol [serial online] 2019 [cited 2020 Feb 17];85:81-2. Available from: http://www.ijdvl.com/text.asp?2019/85/1/81/245895
This letter pertains to the article by Mittal and Mahajan in the July–August 2018 issue of the IJDVL. It is with great interest and appreciation that we have read this experimental paper on “Intramatricial injections for nail psoriasis: An open-label comparative study of triamcinolone, methotrexate, and cyclosporine.” The concept of using a direct intramatricial delivery of antipsoriatic agents in nail psoriasis is indeed promising. However, there are some points we would like to highlight with regard to this study:
- This study may have overlooked the fact that the formulations of antipsoriatic agents injected intramatricially in this study are not depot agents and the effect is not likely to last 24 weeks. With regards to drug kinetics, the elimination half-life of cyclosporine is 5–18 h. Cyclosporine is extensively metabolized by the cytochrome P-450 3A4 (CYP3A4) enzyme system in the liver and is primarily excreted by way of the bile through feces, with only 6% of the dose (parent drug and metabolites) excreted in urine. Further, the usually reported mean values for the elimination half-life and the total body clearance of methotrexate is 5–8 h. Hence if the intramatricial drug worked like a depot agent and its action lasted for 24 weeks after two injections, it would be contradictory as to why we need to give systemic cyclosporine daily and methotrexate weekly to achieve desired therapeutic efficacy in psoriasis vulgaris.
- Reverse Koebner phenomenon, even though rare, was first described in a psoriasis patient. It is defined as the nonappearance or disappearance of the lesions of particular dermatoses at the site of injury.,, Even though there are no reports of reverse Koebner phenomenon in nail psoriasis, we would like to clarify if the results in this study can be attributed to the same.
- Beau's lines are transverse depressions in the nail plate that occur after a stressful event that temporarily interrupts nail formation. The literature available on mechanism of action of antipsoriatic agents on nail psoriasis is relatively sparse. However, if there is an antiproliferative effect and immediate improvement as reported in this study, would the chances of finding Beau's lines as a sign of temporary arrest of growth of nails be likely?
In conclusion, even though we highly appreciate the effort taken by authors, it would be worthwhile if we could postulate the rationale of mechanism of action of these antipsoriatic agents on nail psoriasis to help us understand better.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Mittal J, Mahajan BB. Intramatricial injections for nail psoriasis: An open-label comparative study of triamcinolone, methotrexate, and cyclosporine. Indian J Dermatol Venereol Leprol 2018;84:419-23.
] [Full text]
Wolverton SE. Comprehensive Dermatologic Drug Therapy. Philadelphia: Saunders; 2001.
Bannwarth B, Péhourcq F, Schaeverbeke T, Dehais J. Clinical pharmacokinetics of low-dose pulse methotrexate in rheumatoid arthritis. Clin Pharmacokinet 1996;30:194-210.
Grekin DA, Van Scott EJ. Dermal role and controls in psoriasis. Arch Dermatol 1973;108:425.
Malakar S, Dhar S. Spontaneous repigmentation of vitiligo patches distant from the autologous skin graft sites: A remote reverse Koebner's phenomenon? Dermatology 1998;197:274.
Martín JM, Conde A, Pinazo I, García L, Sánchez AL, Pinazo J, et al.
Reverse koebnerization after radiotherapy in a woman with a mastectomy for a breast carcinoma. J Am Acad Dermatol 2006;55:S90-1.
De Berker D. What do Beau's lines mean? Int J Dermatol 1994;33:545-6.