Case 1 A 70-year-old housewife presented to us with multiple, asymptomatic.
depressed, crateriform plaque lesions over the radial margin of the index
finger and thumb and thenar and hypothenar eminences of both hands of 25 ye
ars' duration (Fig. 1). There was no history of prolonged sun exposure or r
epeated trauma to the hands and there were no such lesions on the soles. No
ne of her other family members were affected. We made a provisional diagnos
is of keratoelastoidosis marginalis. Skin biopsy revealed an unremarkable e
pidermis, with minimal lymphocytic infiltration in the upper dermis and hya
linization in the reticular dermis, extending to the deeper dermis. Two yea
rs later she returned with well-defined, erythematous, scaly, mildly itchy
plaque lesions over the instep of both feet and the center of both palms. A
clinical diagnosis of palmoplantar psoriasis was made.
A careful search to discover any correlation between these two disorders re
vealed that plaque lesions with a central saucer-like depression on the sid
es of the fingers and the palmar surface have been noted in patients with o
therwise typical lesions of psoriasis (Caro MR, Senear FE. Psoriasis of the
hands, Nonpustular type, AMA. Arch Dermatol Syphilol 1956; 74: 629-633). W
e then began to look for these lesions in all patients attending our dermat
ology clinic. Screening of more than 500 patients suffering from cutaneous
disorders other than psoriasis revealed no marginal keratodermas. A careful
search of 500 consecutive patients attending our psoriasis clinic revealed
two more cases.
Case 2 A 23-year-old laboratory technician with psoriasis over the center o
f the palms of 6 months' duration was found to have multiple depressed plaq
ues of 3 x 3 mm along the outer margin of the index finger and inner margin
of the thumb on examination (Fig. 2). These had been present before the ap
pearance of classical psoriasis lesions, but the exact duration was not kno
wn.
Case 3 A 62-year-old shopkeeper with generalized psoriasis of 2 years' dura
tion was found to have pin-head to pea-sized asymptomatic depressed lesions
over the margins of the index finger and thumb (Fig. 3). He was worried ab
out them mainly due to their cosmetic appearance. None of the above patient
s had any gross evidence of actinic damage. All the lesions were craterifor
m, with no elevated or translucent lesions seen.