Actinic reticuloid: immunohistochemical analysis of the cutaneous infiltrate in 13 patients

Clinical Features and Histological Findings of 17 Patients with Chronic Actinic Dermatitis

ObjectivesThis study was designed to evaluate the clinical, histological and immunohistochemical findings and treatment of chronic actinic dermatitis in Korean patients. MethodsSeventeen Korean patients with chronic actinic dermatitis were enrolled for this study. The clinical and histological findings and the results of phototest were reviewed with medical records, clinical photographs and pathologic slides. We also reviewed the effectiveness of the treatments in all patients with chronic actinic dermatitis. ResultsIn all patients with chronic actinic dermatitis, pruritus was severe, and the patients present in the early stages with erythemas on the face, neck and the back of the hands. As the eruption progresses, it became lichenified and scaly plaques and papules developed. The face, upper extremity and neck were most commonly affected. The most common abnormal results of the phototests were decreased MED-UVB alone. In 8 patients with actinic reticuloid, histopathologic findings showed irregular acanthosis, parakeratosis, spongiosis, atypical hyperchromatic cells with cerebriform nuclei, epidermotropism, Pautrier-like microabscess, deep perivascular lymphocytic infiltrates, vertically-streaked collagen in the papillary dermis, stellate and multinucleated fibroblasts. Treatment includes topical tacrolimus and corticosteroid, oral corticosteroid, azathioprine and cyclosporine. ConclusionsOur study showed classic clinical and histological findings. The most common abnormal results of the phototests were decreased MED-UVB alone. Topical steroid, tacrolimus and systemic cyclosporine, azathioprine are effective in treating chronic actinic dermatitis.

Case report of four patients with erythrodermic cutaneous T-cell lymphoma and severe photosensitivity mimicking chronic actinic dermatitis

The marked photosensitivity associated with chronic actinic dermatitis (CAD) is presumed to be due to a T cell-mediated response to ultraviolet (UV)-induced epidermal neoantigens. Photosensitivity is, however, a rare occurrence in cutaneous T-cell lymphoma (CTCL). We discuss a series of four patients with erythrodermic CTCL who exhibited marked photosensitivity mimicking CAD. Significantly, the tumour cells had a CD8 phenotype in half of these patients. All patients had T-cell clones in skin and also demonstrated identical peripheral T-cell clones in blood or lymph node involvement. Sézary cell counts ranged from 6% to 20%, CD4/CD8 ratios from 0.22 to 23.5. Clinical presentation was striking for a marked photosensitive distribution. Monochromator irradiation testing revealed reduced minimal erythema doses throughout UVB and UVA ranges, findings consistent with those seen in CAD. All patients subsequently died from systemic disease. These findings suggest that, rarely, malignant clonal T-cell populations may recognize a unique UV-induced neoantigen, resulting in the clinical features of severe photosensitivity mimicking those seen in CAD.

A case of chronic actinic dermatitis treated with topical tacrolimus

INTRODUCTION

The treatment of chronic actinic dermatitis (CAD), a sun-induced disorder characterized by a persistent eczematous eruption, involves photoprotective measures, topical corticosteroid therapy and, in more severe cases, systemic immunosuppression. The potential side effects of systemic immunosuppressant drugs prompted us to evaluate the efficacy of topical tacrolimus for treatment of CAD. PATIENT AND TREATMENT: A 58-year-old man with CAD, resistant to previous treatment with topical and systemic corticosteroids, oral cyclosporine and PUVA-photochemotherapy, was treated with tacrolimus ointment 0.1% once a day.

RESULTS

Tacrolimus ointment led to significant improvement of pruritus and severe eczematous skin lesions after 20 days of treatment.

CONCLUSIONS

Tacrolimus shows a beneficial effect on CAD; this could be attributed to the fact that CAD is characterized by a lymphohistiocytic infiltrate producing a chronic eczema and that tacrolimus blocks the activation of lymphocytes and other immune system cells, also inhibiting the release of mediators from cutaneous mast cells and basophils.

Photosensitive mycosis fungoides or actinic reticuloid?

We report two patients who satisfied the diagnostic criteria for actinic reticuloid (AR) on initial presentation, in whom genotypic analysis of early skin biopsies failed to show T-cell gene receptor rearrangements. Both patients progressed to widespread skin involvement associated with histopathological and genotypic features of mycosis fungoides (MF). Arguably, these patients may have had photosensitive MF from the outset, but their clinical features, phototesting, and subsequent demonstration of a T-cell gene receptor rearrangement in the skin could also suggest progression of AR to MF.

The idiopathic photodermatoses

The idiopathic photodermatoses present a challenge for dermatologists. Although, as in other specialty areas, the classical clinical presentation produces few problems, it is the severe forms and overlap cases that cause the most difficulty. It is fortunate that the semi-objective investigation of phototesting is available, which, when conducted carefully, reveals so much about the nature of this group of conditions. This essential investigation not only helps achieve a diagnosis, but also affords material for study and a means of monitoring therapy response or progress towards spontaneous resolution. Although these conditions are grouped together, throughout this century we have seen a continuing process of distinct diseases emerging as a consequence of careful clinical observation and investigation.

Cutaneous pseudolymphomas

Cutaneous pseudolymphoma refers to a heterogeneous group of benign reactive T- or B-cell lymphoproliferative processes of diverse causes that simulate cutaneous lymphomas clinically and/or histologically. The inflammatory infiltrate is bandlike, nodular, or diffuse and is composed predominantly of lymphocytes with or without other inflammatory cells. Depending on the predominant cell type in the infiltrate, cutaneous pseudolymphomas are divided into T- and B-cell pseudolymphomas. Cutaneous T-cell pseudolymphomas include idiopathic cutaneous T-cell pseudolymphoma, lymphomatoid drug reactions, lymphomatoid contact dermatitis, persistent nodular arthropod-bite reactions, nodular scabies, actinic reticuloid, and lymphomatoid papulosis. Cutaneous B-cell pseudolymphomas include idiopathic lymphocytoma cutis, borrelial lymphocytoma cutis, tattoo-induced lymphocytoma cutis, post-zoster scar lymphocytoma cutis, and some persistent nodular arthropod-bite reactions. This review attempts to discuss current aspects of the classification, pathogenesis, clinical spectrum, histopathologic and immunohistochemical diagnosis, and laboratory investigations for clonality in the various types of cutaneous pseudolymphomas.

Cellular sensitivity to oxidative stress in the photosensitivity dermatitis/actinic reticuloid syndrome

Skin fibroblasts from certain patients with the photosensitivity dermatitis/actinic reticuloid syndrome show enhanced sensitivity to ultraviolet radiation compared to normal fibroblasts. To probe further the link between oxidative damage and this disease, we have obtained a more extensive set of cell lines from patients with a severe form of the disease and examined their sensitivity towards oxidative stress by measuring cell survival following UVA radiation (330-450 nm) or hydrogen peroxide treatment (0.1-2.4 mM). The activation of the stress gene, heme oxygenase, has also been assessed by measuring the accumulation of mRNA after hydrogen peroxide treatment. Our studies have confirmed that a slight ultraviolet sensitivity is a characteristic of photosensitivity dermatitis/actinic reticuloid syndrome cell strains and we further demonstrate that these cell lines are particularly sensitive to hydrogen peroxide with up to a three- to fourfold increased sensitivity as compared to normal controls. We also show that certain ataxia telangiectasia strains that are especially sensitive to hydrogen peroxide are also slightly sensitive to ultraviolet radiation. Hydrogen peroxide induces accumulation of mRNA for the oxidant-inducible stress protein, heme oxygenase, with similar kinetics (maximum mRNA accumulation 2-4 h following treatment) and with a similar range of magnitudes in both normal (6.6-20.6 times mRNA increase over basal levels) and photosensitivity dermatitis/actinic reticuloid (2.9-12.8 times) skin cells. Because cells from photosensitivity dermatitis/actinic reticuloid patients show increased sensitivity towards oxidative stress but show no significant change in oxidant activation of the heme oxygenase gene, we propose that the defect involves a late stage of processing of oxidative damage rather than a compromised free radical scavenging system.

Chronic actinic dermatitis

Chronic actinic dermatitis (CAD) is one of the most frequently encountered photodermatoses in patients older than 50 years of age. It is characterized by persistent redness of the face and other exposed areas. CAD can become so severe that even nonexposed parts of the body develop eczematous lesions and the disease persists during winter. The diagnosis must be confirmed by phototests that show a broad action spectrum with low threshold doses. CAD must be differentiated from photocontact allergy and airborne dermatitis. The histopathologic features in the early stages are comparable to contact dermatitis, whereas in the later stages they may be those of pseudolymphoma. The most popular treatments are azathioprine and PUVA.

Chronic actinic dermatitis with vitiligo-like depigmentation

This report describes two patients suffering from severe chronic actinic dermatitis. Unusual widespread vitiligo-like depigmentation occurred during the course of the disease. The progression of these lesions was triggered by the chronic actinic dermatitis. Loss of pigment and complete absence of tyrosinase positive melanocytes were found in depigmented skin of both cases. Immunohistological investigation of the inflammatory infiltrate in case 2 revealed a predominance of CD-8 positive cytotoxic/-suppressor lymphocytes. Analysing the adjacent pigmented epidermis of progressive depigmenting lesions a dense exocytosis of CD-8 T-cells was notable. This distribution suggests cytotoxic destruction of melanocytes as the cause for the vitiligo-like depigmentation.

Cell-bound IgE and increased expression of Fc epsilon-receptors on dendritic cells in cutaneous infiltrates of mycosis fungoides

Skin biopsies of 31 non-atopic patients, 20 with mycosis fungoides, six with psoriasis and five with contact dermatitis, and of five non-atopic healthy controls were compared for the presence of cell-bound IgE and vacant IgE binding sites. IgE+ cells were demonstrated in the cutaneous infiltrate of nine (45%) patients with mycosis fungoides, two (33%) with psoriasis and one (20%) with contact dermatitis. Following pre-incubation of skin sections with IgE myeloma protein to saturate vacant IgE-binding sites, 14 out of 16 patients (88%) with stage I mycosis fungoides, five (83%) patients with psoriasis and one (20%) with contact dermatitis showed an increase in the number of IgE+ cells. While cell-bound IgE was positively related to serum IgE levels the expression of IgE-binding sites was not. All IgE+ cells were HLA-DR+ dendritic cells identified as either macrophages (CD68+, CD14+) or Langerhans cells (CD1+). Skin biopsies of non-atopic healthy controls or clinically uninvolved skin in mycosis fungoides had neither any IgE+ cells nor any vacant binding sites. Inhibition studies with IgG1, IgG4 and IgE myeloma proteins as well as with several enzymatic fragments of IgE demonstrated that IgE interacted with Fc epsilon-receptors through isotype-specific structures on the Fc epsilon-fragment. Four anti-CD23 monoclonal antibodies, however, were unable to stain vacant Fc epsilon-receptors nor could they block IgE-binding. We hypothesize that locally-secreted lymphokines, like IL-4 or interferon-gamma, induce Fc epsilon-receptors on dendritic cells in the cutaneous infiltrate and that these receptors become occupied in parallel with elevated serum IgE levels.

Photosensitivity in the elderly

Photosensitivity to drugs and chemicals in the elderly is more prevalent due to more frequent use of medications. Phototoxic reactions to common, orally administered drugs such as diuretics, cardiac agents and antidiabetics may occur and the reactions may be remedied by discontinuing drug therapy. Photocontact dermatitis due to the ingredients in sunscreens or other agents, such as perfumes, may also arise. Diagnosis is often confirmed by photopatch testing and subsequent avoidance of these agents leads to gradual resolution. Idiopathic photodermatoses, such as sunlight-induced polymorphic light eruption or solar urticaria, may occur and persist from an early age and, in elderly subjects, they can cause mild to marked disability. The most disturbing disorder of this type is the severe, widespread eczematous chronic actinic dermatitis, which can be difficult to diagnose. Porphyrias, such as variegate porphyria or erythropoietic protoporphyria, may persist from an early age, whereas porphyria cutanea tarda generally begins in later life. Porphyrias all have specific clinical and biochemical features and, apart from variegate porphyria, usually respond well to treatment following diagnosis. Exposure of elderly skin to sunlight may also cause deterioration of many ordinary dermatoses, particularly seborrhoeic eczema, which generally respond to protection from UV exposure and to treatment of the underlying abnormality. Progress in identifying the underlying causes, the availability of increasingly sophisticated diagnostic techniques, and improvements in sunscreen preparations and therapeutic medications will probably significantly reduce abnormal photosensitivity in the elderly in the near future.