Indian Journal of Dermatopathology and Diagnostic Dermatology

LETTER TO EDITOR
Year
: 2020  |  Volume : 7  |  Issue : 1  |  Page : 50--51

Punctate porokeratosis presenting as papules along palmar and plantar creases


Azra N Fathima, Anuradha Priyadarshini, Mahalakshmi Veeraraghavan, Murugan Sundaram 
 Department of Dermatology, Venereology and Leprology, Sri Ramachandra Institute of Higher Education and Research Institute, Chennai, Tamil Nadu, India

Correspondence Address:
Anuradha Priyadarshini
Department of Dermatology, Venereology and Leprology, Sri Ramachandra Institute of Higher Education and Research Institute, Chennai, Tamil Nadu
India




How to cite this article:
Fathima AN, Priyadarshini A, Veeraraghavan M, Sundaram M. Punctate porokeratosis presenting as papules along palmar and plantar creases.Indian J Dermatopathol Diagn Dermatol 2020;7:50-51


How to cite this URL:
Fathima AN, Priyadarshini A, Veeraraghavan M, Sundaram M. Punctate porokeratosis presenting as papules along palmar and plantar creases. Indian J Dermatopathol Diagn Dermatol [serial online] 2020 [cited 2021 Sep 23 ];7:50-51
Available from: https://www.ijdpdd.com/text.asp?2020/7/1/50/285807


Full Text



Sir,

Porokeratosis is a benign clonal expansion of abnormally differentiating keratinocytes.[1] It refers to a group of disorders characterized by a distinct “thread-like” hyperkeratotic ridge.[2] Punctate porokeratosis is a rare clinical type.[3]

A 24-year-old male presented with asymptomatic multiple spiny lesions over both palms and right sole for 3 months. He had mild pain on lifting heavyweights. The patient did not have any history of exposure to chemicals or arsenic exposure. He did not give a history of similar lesions elsewhere. There was no family history of the same. On examination, the patient had multiple hyperkeratotic papules of size 1–3 mm over the palmar creases of both hands [Figure 1]a and [Figure 1]b and plantar crease of the right great toe [Figure 1]c. No tenderness or oozing was noted. Differential diagnoses of punctate keratoderma, verruca, keratosis punctata of the palmoplantar creases, and punctate porokeratosis were considered. Skin biopsy revealed a column of parakeratotic keratinocytes from an epidermal invagination through stratum corneum suggesting cornoid lamella [Figure 2]a and thin granular layer beneath [Figure 2]b. Based on these findings, he was diagnosed with punctate porokeratosis and was treated with topical 5% 5-fluorouracil for 6 weeks and he had marked improvement [Figure 3]a, [Figure 3]b, [Figure 3]c.{Figure 1}{Figure 2}{Figure 3}

Mibelli in 1893 coined the term “porokeratosis.”[2] At least six types of porokeratosis have been recognized, of which punctate porokeratosis, first reported by Guss in 1971, is a rare type.[4] Two hypotheses have been proposed. Reed proposed that porokeratosis is an expanding mutant clone of keratinocytes by triggering factors such as ultraviolet radiation and immunosuppression in genetically predisposed individuals. The second hypothesis states that unidentified epidermal antigen triggers inflammatory mediators acting as a mitotic stimulus for keratinocytes.[3] Punctate porokeratosis appears as “seed-like” hyperkeratotic papules with a raised peripheral rim on palms and soles during adolescence. Porokeratosis palmaris et plantaris disseminata is a rare autosomal dominant variant of punctate porokeratosis in which palmoplantar lesions occur in adolescence, followed by disseminated wart-like lesions all over the body.[1] There was no family history of porokeratosis in this patient; however, there is a possibility of disseminated lesions; thus, the patient is on regular follow-up. Clinical differential diagnoses include arsenical keratosis, verruca, keratosis punctata of the palmar and plantar creases, spiny keratoderma, and porokeratotic eccrine ostial and dermal duct nevus.[5] On histopathology, a parakeratotic column, the cornoid lamella, represents the most characteristic feature of porokeratosis. Although cornoid lamella is characteristic, it can also be seen in actinic keratosis and verruca. The absence of cellular atypia helps to rule out actinic keratosis, and the absence of koilocytes helps to rule out verruca.[2] The principle of treatment is to target the two basic mechanisms – abnormal clone of cells and abnormal keratinization. Topical treatment options include 5-fluorouracil, imiquimod, diclofenac, Vitamin D analogs, and photodynamic therapy. Other options include cryotherapy, curettage, cautery, and CO2 laser and oral retinoids.[1]

We report this case to highlight that punctate porokeratosis should be considered as a differential diagnosis of palmoplantar papules, a different presentation of palmoplantar porokeratosis limited to creases alone, and therapeutic efficacy of 5-fluorouracil.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Chu AC, Teixeira F. Acquired disorders of epidermal keratinization. In: Griffiths CE, Barker J, Bleiker T, Chalmers R, Creamer D, editors. ROOK'S Textbook of Dermatology. 9th ed. West Sussex, UK: John Wiley & Sons, Limited; 2016. p. 87.18, 87.20, 87.22.
2Arkin L, Lee LW, Rubin AI, Yan AC. Congenital diseases (Genodermatoses). In: Elder DE, editor. Lever's Histopathology of the Skin. 11th ed. Philadelphia: Wolters Kluwer; 2015. p. 154-6.
3Requena L, Requena C, Cockerell CJ. Benign epidermal tumours and proliferations. In: Bolognia JL, Schaffer JV, Cerroni L, editors. Dermatology. 4th ed. Spain: Elsevier Limited; 2018. p. 1901-4.
4Lanka P, Lanka LR, Manivachagam D. Punctate porokeratosis palmaris et plantaris. Indian J Dermatol 2015;60:284.
5Puzzling Palmar Papules and Pits. MDedge Family Medicine. Available from: https://www.mdedge.com/familymedicine/article/60328/der matology/puzzling-palmar-papules-and-pits. [Last accessed on 2019 Oct 01].