|Year : 2021 | Volume
| Issue : 2 | Page : 213-216
A case series of disseminated porokeratosis
J Logeshwari, Nippa Devi A Patel, Sirisha Varala, Ananthula Venkata Krishna
Department of Dermatology, Venereology and Leprology, Osmania Medical College, Osmania General Hospital, Hyderabad, Telangana, India
|Date of Submission||17-Jun-2020|
|Date of Decision||22-Sep-2020|
|Date of Acceptance||23-Nov-2020|
|Date of Web Publication||26-Aug-2021|
Department of Dermatology, Venereology and Leprology, Osmania Medical College, Osmania General Hospital, Hyderabad, Telangana
Source of Support: None, Conflict of Interest: None
Porokeratosis is an autosomal dominant disorder of epidermal keratinization resulting from abnormal expansion of latent clones following chronic ultraviolet exposure or immunosuppression. Various clinical and morphological variants of porokeratosis are present, among which disseminated superficial actinic porokeratosis (DSAP) is the most common subtype located predominantly on the sun exposed areas, whereas disseminated superficial porokeratosis (DSP) is present both on the sun exposed and sun protected areas including oral mucosa and genitalia. Porokeratosis is characterized clinically by annular plaques with atrophic center and thready border and histologically by the presence of cornoid lamella. DSAP may be missed because of its inconspicuous nature in dark skinned individuals and may sometimes be mistaken for actinic keratoses in sun-damaged skin. Here, we report a case series of five patients with disseminated porokeratosis with varied presentations.
Keywords: Cornoid lamella, disseminated superficial actinic porokeratosis, disseminated superficial porokeratosis, porokeratosis
|How to cite this article:|
Logeshwari J, A Patel ND, Varala S, Krishna AV. A case series of disseminated porokeratosis. Clin Dermatol Rev 2021;5:213-6
| Introduction|| |
Vittorio Mibelli described the term porokeratosis. Clinical variants are classical porokeratosis of Mibelli, linear porokeratosis (LP), disseminated superficial porokeratosis (DSP), disseminated superficial actinic porokeratosis (DSAP), and porokeratosis palmaris et plantaris disseminate. Among these different clinical types, DSAP is the most common. Various morphological variants such as, hypertrophic, giant, punctuate, and reticulate porokeratosis have been described in the literature.
| Case Reports|| |
An 80-year-old woman presented with non-itchy bilaterally symmetrical lesions predominantly on the exposed areas over face, neck, and upper limbs of 3 years duration. On cutaneous examination multiple, discrete, bilaterally symmetrical, hyperpigmented, annular plaques of 1–3 cm diameter with slightly elevated borders were seen over the face, neck, and bilateral forearms [Figure 1]a. Histopathological examination (HPE) showed characteristic cornoid lamella with thinned out epidermis which was suggestive of DSAP [Figure 1]b.
|Figure 1: (a) Thin annular plaques with hyperpigmented thready borders over left infraorbital area and left cheek. (b) Skin biopsy showing characteristic cornoid lamella with atrophic epidermis (H and E, 40x)|
Click here to view
A 65-year-old male patient presented with multiple, itchy, annular lesions over scalp, face, trunk, extremities involving palms and soles and scrotum of 3 years duration. He had history of photosensitivity. The lesions initially started over face and neck, then gradually progressed to involve the other areas. Cutaneous examination revealed multiple, discrete, hyperpigmented annular plaques of 1–3 cm diameter with a slightly raised border over the face- neck, back, bilateral forearms, palms, soles and scrotum. Few verrucous, hyperkeratotic annular plaques of sizes ranging from 1 to 4 cm diameter were noted over dorsum of feet and lower back [Figure 2]a, [Figure 2]b, [Figure 2]c, [Figure 2]d. Routine blood investigations were within normal limits. Ultrasound abdomen was normal. HIV serology was found to be non-reactive. Provisional diagnosis of DSP with coexistence of palmoplantar and genital porokeratosis was made. This was confirmed by the presence of cornoid lamella on HPE. Dermoscopy showed a double “white track” structure at the margin of the lesion with brownish pigmentation on the inner side [Figure 3].
|Figure 2: (a) Thin annular hyperpigmented plaques with elevated borders over left mandibular and inframandibular areas. (b) Single polycyclic hyperpigmented plaque of size 5 cm × 1 cm with an elevated grooved border over dorsum of left foot adjacent to which is a single hypertrophic, hyperpigmented nodule of size 1 cm × 1 cm. (c) Yellowish hyperkeratotic plaques with furrowed borders over left palm. (d) Multiple annular and polycyclic hyperpigmented plaques with elevated border all over the scrotum|
Click here to view
|Figure 3: Dermoscopy image with 10x magnification showing double white track structure at the margin of the plaque with central brownish pigmentation|
Click here to view
Three cases presented from the same family. A 55-year-old female patient [Case 3] presented to our department with her two daughters, elder daughter, 23 years [Case 4] and younger, 20-years old [Case 5]. Mother had complaints of multiple asymptomatic hyperpigmented skin lesions over face, neck, and extremities of 16 years duration. Both daughters had similar complaints of 2 years duration. There is history of aggravation of lesions on exposure to sunlight. Other family members were normal. On examination, all three patients had multiple, discrete, well-defined, hyperpigmented, annular plaques with thready borders located over the face, neck, extensor aspects of bilateral hands and forearms [Figure 4]a, [Figure 4]b,[Figure 4]c. Genetic analysis was not done due to financial constraints. HPE of case 4 was suggestive of DSAP [Figure 4]d.
|Figure 4: (a-c) Thin annular hyperpigmented plaques with thready borders over the face of cases 3, 4, 5 respectively. (d) Histopathology showing hyperkeratosis, parakeratotic cornoid lamella and acanthosis in the epidermis (H and E, 4x)|
Click here to view
| Discussion|| |
DSAP was first described by Chernosky and Freeman in 1967. Pathogenesis involves heterozygous mutations in mevalonate kinase enzyme. Blockage of the mevalonate pathway in DSAP causes mitochondrial dysfunction and consequently induces apoptosis of keratinocytes. Triggering factors includes ultraviolet light, trauma, infection, and immunosuppression. Associated conditions include internal malignancies, diabetes, liver disease, organ transplantation, and HIV. However, our patients did not have immunosuppression or any other associated conditions. DSAP is more common in women and usually manifests in third and fourth decade of life. In our case series, while three female patients with DSAP from the same family (cases 3, 4 and 5) presented in early adult life, one elderly female (case 1) had a late onset presentation in the seventh decade.
DSAP tends to occur in families. Welton reported simultaneous presentation of DSAP and LP in one woman, while her three sisters had only DSAP. Similarly, in our case series there is a familial occurrence of DSAP in mother and her two daughters. However genetic analysis could not be done in our patients because of financial limitations.
DSAP is characterized clinically by multiple asymptomatic papules coalescing to form annular plaques with peripheral keratotic rim in a symmetrical distribution on the sun exposed areas. Lesions are often induced and exacerbated by ultraviolet light. However, only 15% of DSAP cases may have facial involvement, and exclusive facial presentation is extremely rare. In Chernosky and Freeman study, five of 31 subjects had facial lesions. Though rare, all our five patients had lesions on face.
DSP is a rare variant seen mostly in children and immunocompromised patients. It can be distinguished from DSAP by the involvement of both sun-protected and sun-exposed sites. In our case series, one male patient presented with late onset DSP coexisting with palmoplantar and genital porokeratosis with no underlying signs of immunosuppression as similar to the case reported by Pruitt et al.
It is not uncommon for various morphological subtypes to be present in the same patient. Bhaskar et al. reported a head to toe presentation of various subtypes of porokeratosis with involvement of uncommon sites. Case two in our case series, who is an elderly male, presented with coexistence of DSP with palmoplantar and genital porokeratosis and a morphological variant with hypertrophic form. The involvement of groins and genitalia are rare even in disseminated form of porokeratosis. Most of the reported cases of genital porokeratosis in the literature showed predominant involvement of the scrotum which was also the scenario in our case. However, in the case of DSP reported by Pruitt et al., penile involvement was also present in addition to scrotal involvement. Recognizing genital porokeratosis is important to avoid misdiagnosis as sexually transmitted disease.
Histologically, porokeratosis is characterized by a vertical column of tightly packed parakeratotic keratinocytes within an epidermal invagination called cornoid lamella. All our patients had characteristic cornoid lamella on HPE. Dermoscopy done in one patient showed a “white-track” structure at the margin corresponding to the cornoid lamella and the central brown lines indicating acanthotic epithelium findings which are similar to those by Bhaskar et al.
Treatment includes sun protection, topicals such as diclofenac, imiquimod, calcipotriol, steroids, and 5-fluorouracil. Other options are cryotherapy, photodynamic therapy, carbon dioxide laser, radiotherapy with grenz rays and systemic retinoids. Long standing lesions, larger lesions, linear type are at high risk of developing Bowen's disease, squamous cell, and spinous cell carcinomas. Hence, these patients should be monitored regularly for the risk of malignant transformations. Case 1 and case 2 in our study were started on systemic retinoids and are under regular follow-up. We have lost the follow-up of cases 3, 4, 5.
We are reporting this case series of disseminated porokeratosis because of its varied presentations and involvement of unusual sites.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initial s will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Dover JS, Phillips TJ, Burns DA, Krafchik BR. Disseminated superficial actinic porokeratosis. Coexistence with other porokeratotic variants. Arch Dermatol 1986;122:887-9.
Bhaskar S, Jaiswal AK, Raj N, Reddy D. Porokeratosis - Head to toe: An unusual presentation. Indian Dermatol Online J 2015;6:101-4.
] [Full text]
Chernosky ME, Freeman RG. Disseminated superficial actinic porokeratosis (DSAP). Arch Dermatol 1967;96:611-24.
Sethi P, Kumari N, Adhlakha B, Kanwar AJ. Focal actinic porokeratosis: A new variant? Indian J Paediatr Dermatol. 2018;19:272-3.
Welton WA. Linear porokeratosis in a family with DSAP. Arch Dermatol 1972;106:263.
Pruitt LG, Hsia LL, Burke WA. Disseminated superficial porokeratosis involving the groin and genitalia in a 72-year-old immunocompetent man. JAAD Case Rep 2015;1:277-9.
Sengupta S, Das JK, Gangopadhyay A. Porokeratosis confined to the genital area: A report of three cases. Indian J Dermatol Venereol Leprol 2008;74:80.
] [Full text]
Liang C, Batra P, Patel R, Kamino H. Genital porokeratosis. Dermatol Online J 2009;15:23.
Shumack SP, Commens CA. Disseminated superficial actinic porokeratosis: A clinical study. J Am Acad Dermatol 1989;20:1015-22.
Thomaidou E, Katz M, Leibovici V. Two cases of disseminated superficial actinic porokeratosis (DSAP) and treatment literature review. Our Dermatol Online 2018;9:241-8.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]