ARTICLE
A 76-year-old man presented with a long history of asymptomatic erythematous
skin changes. On examination, erythematous, finger-shaped plaques with
a marked tendency to palisading were found on the trunk and on the proximal
aspects of the limbs (Fig. 1)
A skin biopsy specimen revealed superficial, perivascular, lymphocytic
infiltrates as well as spongiosis and parakeratosis. General physical
and laboratory examinations were unremarkable.
Digitate dermatosis
Since Brocq first proposed the term parapsoriasis in 1902 many synonyms
and classifications of the parapsoriasis group have been used. Nowadays,
parapsoriasis is clinically divided into three entities, with subtypes
as follows: pityriasis lichenoides, small plaque parapsoriasis and large
plaque parapsoriasis. Benign small plaque parapsoriasis
(chronic superficial dermatitis), usually appearing with lesions smaller
than 5 cm in diameter, is clinically and prognostically distinguished
from large plaque parapsoriasis, which is known to progress to cutaneous
lymphoma in about 10% of cases [1-3]. Digitate dermatosis has a chronic
course and is generally described as a clinical variant of small plaque
parapsoriasis, however, there are authors who consider digitate dermatosis
and small plaque parapsoriasis to be synonymous [4, 5]. Characteristically
in digitate dermatosis, pink or erythematous, elongated plaques occur
along the tension lines. In rare cases, finger-shaped
lesions show a marked tendency to palisading as shown in the present case.
This clinical picture of digitate dermatosis has occasionally been described
as fingerprint parapsoriasis [1, 6, 7]. The histological findings in digitate
dermatosis are predominantly nonspecific, similar to those seen in chronic
dermatitis. Although digitate dermatosis has been suggested to be an abortive
lymphoma, without conversion into systemic lymphoma,
the pathogenesis of this skin disease remains uncertain [4]. Following
four weeks of balneophototherapy, combining salt water baths and subsequent
UVB/UVA irradiation, extensive clearing of the lesions was seen in our
patient.
REFERENCES
1. Lambert WC, Everett MA. The nosology of parapsoriasis. J Am Acad
Dermatol 1981; 5: 373-95.
2. Kikuchi A, Naka W, Harada T, et al. Parapsoriasis en plaques:
its potential for progression to malignant lymphoma. J Am Acad Dermatol
1993; 29: 419-22.
3. Mueller KK, Yeager JK. Clinical considerations in digitate dermatosis.
Int J Dermatol 1997; 36: 764-78.
4. Burg G, Dummer R. Small plaque (digitate) parapsoriasis is an abortive
cutaneous T cell lymphoma and is not mycosis fungoides. Arch Dermatol
1995; 131: 336-8.
5. King-Ismael D, Ackermann AB. Guttate parapsoriasis/digitate dermatosis
(small plaque parapsoriasis) is mycosis fungoides. Am J Dermatopathol
1992; 14: 518-30.
6. Hu C, Winkelmann RK. Digitate dermatosis: a new look at symmetrical,
small plaque parapsoriasis. Arch Dermatol 1973; 107: 65-9.
7. Lambert WC. Premycotic eruptions. Dermatol Clin 1985; 3: 629-45.
|
Printable version
