A Case of Disseminated Superficial Porokeratosis Associated with Giant Porokeratosis in Pregnancy

Abstract

A 23-year-old pregnant lady presented with dark raised lesions over face, axillae, and upper limbs of 15-day duration. She was 35 weeks pregnant at the time of onset of the lesions. Dermatological examination revealed hyperpigmented plaques on the face and papules with raised borders in the axillae and proximal arms. Skin biopsy from both the lesions revealed a diagnosis of porokeratosis. She was treated with emollients alone and the lesions regressed four weeks following delivery. This case is being reported for the rare occurrence of the combination of disseminated superficial porokeratosis with giant porokeratosis in pregnancy.

What was known?

Porokeratosis is a clonal disorder of keratinization characterized by lesions with an atrophic center, prominent peripheral ridge, and a histologic hallmark in the form of cornoid lamella. Genetics, immunosuppression, and sunlight are some of the factors blamed for its occurrence. Various morphological variants have been described.

Introduction

Porokeratosis is a clonal disorder of keratinization characterized by lesions with an atrophic center, prominent peripheral ridge, and a histologic hallmark in the form of cornoid lamella. Genetics, immunosuppression, and sunlight are some of the factors blamed for its occurrence. Various morphological variants have been described. We herein present a case of giant facial porokeratosis associated with disseminated superficial porokeratosis (DSP) manifesting in the last trimester of pregnancy and disappearing after delivery. To the best of our knowledge, such a morphological association of the two types of porokeratosis as also the occurrence of porokeratosis in pregnancy has not been mentioned earlier in literature.

Case Report

A 23-year-old primipara was referred to the Skin OPD with complaints of sudden-onset, dark raised lesions over face, axillae, and upper limbs of 15-day duration. She was in her 35^th week of pregnancy at the time of onset of the lesions. There was no associated discharge, pain, itching, or photosensitivity associated with the lesions. There was no history of application of any chemicals, intake of drugs, or insect bite prior to appearance of lesions.

Cutaneous examination revealed well-defined, large hyperpigmented plaques ranging from 5 × 6 to 12 × 10 cm present bilaterally over both the malar and mandibular areas of the face [Figure 1]. There was no crusting, scaling, or discharge from the lesions. Multiple, non-folliculocentric, hyperpigmented discrete papules were also present in the axillae [Figure 2], breast, and both arms. These lesions had slightly raised borders.

Figure 1.

Hyperpigmented plaques on the face

Figure 2.

Hyperpigmented papules in the axilla

Skin biopsy done from lesions on the face revealed features of a hyperkeratotic epidermis and a column of parakeratotic stratum corneum cells (cornoid lamella) jutting into the dermis, with the underlying spongiotic keratinocytes having shrunken nuclei along with a moderate dermal lymphocytic infiltrate under the lamella [Figure 3], consistent with a diagnosis of porokeratosis. The biopsy from the axillary lesion revealed similar features except for more prominent hyperkeratosis [Figure 4]. Thus, a combination diagnosis of facial giant porokeratosis with disseminated superficial keratosis was made.

Figure 3.

Histopathology of the face lesion showing the coronoid lamella and other classical findings of porokeratosis (H and E stain- 10×)

Figure 4.

Histopathology of the axillary lesion (H and E stain - 40×)

Considering the asymptomatic course and pregnancy, she was prescribed only emollients for topical application. The lesions started regressing one week postpartum. Four weeks after delivery, there was complete clearance of all skin lesions [Figure 5].

Figure 5.

Regression of the lesion after 4 weeks

Discussion

Porokeratosis is a rare, autosomal dominant, clonal disorder of keratinization with sporadic cases known to occur frequently. There are five classical clinical variants of porokeratosis: classic porokeratosis of Mibelli, porokeratosis palmaris et plantaris disseminate (PPPD), linear porokeratosis, DSP, and disseminated superficial actinic porokeratosis (DSAP). Apart from these five clinical variants, a number of atypical morphological forms such as facial, giant, punched-out, hypertrophic, verrucous, and reticulate porokeratosis have also been reported in literature.[1]

DSP is characterized by small, annular, and brown lesions with raised hyperkeratotic borders and atrophic centers following the progression of the disease. The genetic basis for DSP is unknown, but several genetic loci have been identified to date. Among these loci, a genetic locus for DSP has been found at 18p11.37.[2] Giant porokeratosis is very rare and usually affects the feet. It is considered by many as a variant of porokeratosis of Mibelli.[3] Few cases of facial superficial porokeratosis have been reported earlier.[4] Most of these have been associated with excessive sun exposure[5] and also found to be destructive in nature.[6]

Reported cases of mixed porokeratosis in literature mostly involve DSAP and linear varieties. Four cases of Porokeratosis of Mibelli have been described in association with DSAP.[7,8] A solitary case of giant porokeratosis with PPPD has been described earlier.[5]

DSP of immunosuppression is recognized after renal, hepatic, cardiac, and bone marrow transplantation, and in human immunodeficiency virus infection. In pregnancy too, there is immunosuppression and probably this is the reason for occurrence of porokeratosis in our case. An extensive search of literature has failed to reveal any association of pregnancy and porokeratosis, let alone unusual spontaneous resolution of the same following delivery. Spontaneous regression of the lesions in nonpregnant females has been described in literature. The combination of giant porokeratosis of the face and DSP is also not reported earlier. This case has been presented for its unusual occurrence in pregnancy and rare combination of two variants of porokeratosis in the same patient.

What is new?

A morphological association of giant facial porokeratosis associated with disseminated superficial porokeratosis manifesting in the last trimester of pregnancy and disappearing after delivery as also the occurrence of porokeratosis in pregnancy has not been mentioned earlier in literature.