Atrophic Lingual Plaque in Father-Son Duo.

Abstract

Dear editor, A 24-year-old male presented with a tongue lesion present since adolescence. On examination, he had a single large, sharply demarcated, irregular, depressed plaque on the dorsum of the tongue. Blackish discoloration of the papillae within the lesion was noted. [Figure 1a]. Also, there were multiple, asymptomatic, annular plaques all over the body, slowly increasing in number and size with age. Most of these plaques had a hyperkeratotic double-edged border with a gutter in between with a thread-like margin with atrophy at the center in a few. Similar plaques were present in the buccal mucosa, hard palate, labial commissures, scrotum, glans, and penile shaft. His father also had multiple similar plaques on the tongue as the son, but the center was more atrophic and glazy [Figure 1c]. Furthermore, his father had similar lesions over the body and limbs [Figure 2].Figure 1: Shows (a) clinical picture of son showing a sharply demarcated large irregular plaque with bluish-grey papillae inside the border; (b) mucoscopy of the same lesion of the son with incomplete white peripheral keratotic tract with a double-free edge with few areas showing white radiating lines; (c) clinical picture of the father showing multiple sharply-demarcated plaques with atrophic papillae; (d) mucoscopic picture showing white peripheral keratotic tract with a double-free edge, dotted vessels in irregular distribution and clusters inside the plaque, loss of papillae with brown clods, and white lines in the centerFigure 2: Multiple large annular plaques with double-edged border of classic porokeratosis of Mibelli on back (a) and legs (b) and upper limb (c)Mucoscopy (DermLite DL4; Contact polarized; 10× magnification; ultrasound gel as interface media) of the tongue plaque of the son [Figure 1b] showed incomplete, peripheral, white, double-edged, keratotic tract with few areas showing white radiating lines and brown clods. In contrast, the father [Figure 1d] showed a white peripheral, double-edged, keratotic track with a center showing dotted vessels in irregular distribution and clusters inside the plaque, loss of papillae, brown clods, and white lines. Dermoscopy of the cutaneous lesion of both father and son showed the hyperkeratotic double-edged margin with the characteristic gutter in between and decreased skin markings at the center, which indicated a clinical diagnosis of classic porokeratosis of Mibelli (CPM). Biopsy and histopathological [Figure 3a and b] examination of the tongue lesion of the son showed moderately dense superficial perivascular patchy lichenoid lymphocytic infiltrate with focal interface vacuolar change. In a few places, the epidermis showed an invagination of the floor, which lacked a granular layer, whereas the walls showed hypergranulosis, and the center had a column of dyskeratotic and parakeratotic cells, the cornoid lamellae. It confirmed our clinical diagnosis of multifocal CPM.Figure 3: Showing histopathological findings {Hematoxylin and Eosin, 10 × (a) and 40 × (b)} – moderately dense superficial perivascular patchy lichenoid lymphocytic infiltrate with focal interface vacuolar change, the epidermis showed an invagination of the floor, which lacks granular layer, whereas the walls showed hypergranulosis, and the center had a column of dyskeratotic and parakeratotic cellsAlthough Pororkeratosis is clinically classified as localized and generalized, they are unified by a common histopathological finding of a column of parakeratotic cells with an absent granular layer at the base. Dermoscopy of cutaneous lesions helps diagnose as it accentuates the gutter as white track,[1] which is characteristic of porokeratosis, especially in CPM, as was seen in our case. Ahmed et al.[2] described 26 cases of primary genital porokeratosis in their review. Our literature search of PubMed and Google (till April 2021) and review of reported cases having mucosal porokeratosis [electronic supplement Table e-1] found 18 reports. Out of 21 cases, ten had labial lesions, nine cases had buccal mucosa lesions, and only six had lesions on their tongue (including the present report), making the tongue rarest of the three sites. Only labial porokeratosis was present in isolated form (seven cases), whereas the buccal mucosa lesions always presented with cutaneous lesions. In cases where the lesions were generalized with mucosal involvement (14 cases), buccal mucosal lesions were present in nine cases, six in the tongue, and only two on the lips, making buccal mucosa most common to be affected in generalized forms. Of these 14 cases, eight were of CPM, three each of disseminated superficial porokeratosis (DSP) and porokeratosis palmaris et plantaris disseminata (PPEPD). A total of six cases (including ours) had lingual porokeratosis. Previously, tongue plaque has been seen in two cases of CPM,[34] and one each in PPEPD,[5] and DSP.[6] Our case with widespread mucosal involvement is very rare. Furthermore, we could not find any literature describing the dermoscopic and histopathologic findings of lingual porokeratosis. The mucoscopic findings will help clinicians make outpatient-based spot diagnoses. Consent Consent for publication of the image is taken. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest. Supplement Table