Chronic Actinic Dermatitis/Actinic Reticuloid: A Clinicopathologic and Immunohistochemical Analysis of 37 Cases

HIV-associated photodermatitis in African populations

Photosensitive dermatoses are seen in 5% of HIV-infected persons. These include drug- and chemical-induced photoallergic and phototoxic reactions, chronic actinic dermatitis of HIV, photo lichenoid drug eruptions, and porphyria. Data on photodermatitis in HIV are limited to case reports and series. The pathogenesis is not completely understood and includes a th2 phenotype in HIV which results in impaired barrier function and resultant allergen sensitisation as well as immune dysregulation. The objective of this manuscript is to review the literature on the clinical phenotype, pathogenesis, role of photo and patch testing, outcomes, and treatment of photodermatitis in HIV in an African population.

HIV-Associated Immune Dysregulation in the Skin: A Crucible for Exaggerated Inflammation and Hypersensitivity

Skin diseases are hallmarks of progressive HIV-related immunosuppression, with severe noninfectious inflammatory and hypersensitivity conditions as common as opportunistic infections. Conditions such as papular pruritic eruption are AIDS defining, whereas delayed immune-mediated adverse reactions, mostly cutaneous, occur up to 100-fold more during HIV infection. The skin, constantly in contact with the external environment, has a complex immunity. A dense, tightly junctioned barrier with basal keratinocytes and epidermal Langerhans cells with antimicrobial, innate-activating, and antigen-presenting functions form the frontline. Resident dermal dendritic, mast, macrophage, and innate lymphoid cells play pivotal roles in directing and polarizing appropriate adaptive immune responses and directing effector immune cell trafficking. Sustained viral replication leads to progressive declines in CD4 T cells, whereas Langerhans and dermal dendritic cells serve as viral reservoirs and points of first viral contact in the mucosa. Cutaneous cytokine responses and diminished lymphoid populations create a crucible for exaggerated inflammation and hypersensitivity. However, beyond histopathological description, these manifestations are poorly characterized. This review details normal skin immunology, changes associated with progressive HIV-related immunosuppression, and the characteristic conditions of immune dysregulation increased with HIV. We highlight the main research gaps and several novel tissue-directed strategies to define mechanisms that will provide targeted approaches to prevention or treatment.

Successful Treatment of Chronic Actinic Dermatitis with Dupilumab: A Case Report and Review of the Literature

Chronic actinic dermatitis (CAD) is a rather rare photosensitive disease characterized by a persistent eczematous eruption in sun-exposed sites. The pathogenesis of CAD has not been completely elucidated. The clinical treatment of CAD is still challenging and not standardized. Some patients with severe CAD have achieved satisfactory clinical results with dupilumab when conventional therapies have failed. We herein report the case of a 45-year-old male with severe CAD who responded rapidly to combined treatment with dupilumab (600 mg for 1 week, and then 300 mg every 2 weeks) in 2 months. The patient experienced continuous improvement and no side effects from dupilumab (300 mg every month), having ceased other systemic medications. Dupilumab could be considered as an alternative or adjunctive treatment for CAD.

Clinical and pathological findings of chronic actinic dermatitis

BACKGROUND

Chronic actinic dermatitis (CAD) is a recurrent photosensitive disease occurs predominantly in elderly men on sun-exposed areas, which seriously affect the patient's life quality. The etiology of CAD remains unknown.

METHODS

Sixty-six CAD patients, 66 atopic dermatitis (AD) patients, and 46 healthy people were enrolled into this study. Patient-level data were obtained from the electronic medical record and laboratory databases. We also obtained 29 tissue samples including 16 lichenoid lesions, 7 minimal erythematous dose (MED) analysis induced lesions, and 6 normal skin samples. Histopathologic and immunohistochemical analysis were performed.

RESULTS

In the clinical characteristics, albumin was lower and uric acid was higher significantly in patients diagnosed as CAD. The infection rate of CAD patient after skin biopsy was considerably high (23.3%). The serum allergen test was prone to be negative in CAD patients. Lymphocytes were the dominate infiltrating cells in early and late CAD lesions, while more CD4+, CD8+, CD69+, and CD103 + cells were found in the late lesions. There is no difference in CD4+/CD8 + ratio and CD69+/CD103 + ratio among groups. More mast cells were observed in the early-stage lesions, and more dendritic cell was observed in the late-stage lesions.

CONCLUSIONS

CAD patients have certain oxidative stress and are prone to be infected after skin biopsy. Serum allergen detection is of little significance for CAD diagnosis. Mast cells may be involved in the early process of CAD, while dendritic cells and tissue-resident memory T cell (TRM) may be related to the chronic process of the disease.

Primary Cutaneous CD30+ Anaplastic Large T Cell Lymphoma in a Patient Treated with Cyclosporine for Actinic Reticuloid

Actinic reticuloid (AR)—a subtype of chronic actinic dermatitis—clinically and histopathologically shows lymphoma-like features. We report a male patient initially diagnosed with erythrodermic cutaneous T cell lymphoma (CTCL) who developed severe broadband photosensitivity. Clinical evaluation, histopathology, and phototesting were consistent with AR. The patient was treated with cyclosporine 150–300 mg/d. Under this therapy, he developed several times primary cutaneous anaplastic large cell lymphomas (C-ALCL) which in part tended to regress spontaneously under cyclosporine reduction. The association between cyclosporine treatment and development of C-ALCL and other CD30+ lymphoproliferative disorders has previously been reported in patients with atopic dermatitis, psoriasis, and transplant patients. In conclusion, the present case highlights the difficulties arising in the distinction between AR and CTCL and shows that long-term cyclosporine treatment may cause C-ALCL development in AR as well.

A Systematic Approach to the Cutaneous Lymphoid Infiltrates: A Clinical, Morphologic, and Immunophenotypic Evaluation

CONTEXT.—

The evaluation of cutaneous lymphoid infiltrates, both neoplastic and inflammatory, occurs very frequently in routine dermatopathologic examination and consultation practices. The "tough" cutaneous lymphoid infiltrate is feared by many pathologists; skin biopsies are relatively small, whereas diagnostic possibilities are relatively broad. It is true that cutaneous lymphomas can be difficult to diagnose and that in many circumstances multiple biopsies are required to establish a correct diagnostic interpretation. As a reminder, one should understand that low-grade cutaneous lymphomas are indolent disorders that usually linger for decades and that therapy does not result in disease cure. It is also important to remember that in most circumstances, those patients will die from another process that is completely unrelated to a diagnosis of skin lymphoma (even in the absence of specific therapy).

OBJECTIVE.—

To use a clinicopathologic, immunophenotypic, and molecular approach in the evaluation of common lymphocytic infiltrates.

DATA SOURCES.—

An in-depth analysis of updated literature in the field of cutaneous lymphomas was done, with particular emphasis on updated terminology from the most recent World Health Organization classification of skin and hematologic tumors.

CONCLUSIONS.—

A diagnosis of cutaneous lymphoid infiltrates can be adequately approached using a systematic scheme following the proposed ABCDE system. Overall, cutaneous T- and B-cell lymphomas are rare and "reactive" infiltrates are more common. Evaluation of lymphoid proliferations should start with a good sense of knowledge of the clinical presentation of the lesions, the clinical differential considerations, and a conscientious and appropriate use of immunohistochemistry and molecular tools.

A case report of therapeutically challenging chronic actinic dermatitis

Chronic actinic dermatitis is a difficult to treat photodermatitis. Treatment is not standardized and involves topical corticosteroids and immunomodulators, and systemic immunosuppressive agents. We present a case with partial response to dupilumab, a monoclonal antibody approved for atopic dermatitis. In recalcitrant cases, systemic agents such as methotrexate, azathioprine, mycophenolate mofetil, and thalidomide, extracorpeal electrophoresis, and low-dose psoralen and ultraviolet A can also be considered.

Lymphoma or pseudolymphoma: A report of six cases and review of the literature

To explore and compare the clinical presentations and pathologic features of cutaneous pseudolymphomas (CPL) with primary cutaneous lymphomas. Review literature in order to improve the treatment of CPL. Six cases of CPLs were collected. The clinical, pathologic, and immunohistochemical features were performed and analyzed in Peking Union Medical College Hospital in 2018. Of six patients, the distributions and clinical manifestations of skin lesions are varied. The pathologic features consisted of atypical prominent lymphocytes infiltration. Of them, two cases imitated mycosis fungoides, one case mimicked primary cutaneous aggressive pidermotropic CD8+ cytotoxic T-cell lymphoma, one case was diagnosed as Jessner-Kanof lymphocyte infiltration and two cases primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder. With respect to etiology, one was result from insects bite and the others were on account of drugs. All cases were treated with systemic or local glucocorticoid. The skin lesions and systemic symptoms showed notable improvement after treatment. Follow-up visits were 2 years, half a year, and months, respectively, without relapse. These unique types of CPL were similar to cutaneous lymphomas in clinical manifestation and pathology. They were all sensitive to the treatment of externally or orally using glucocorticoid. The prognosis is generally good but needs long-term follow-up.

Mogamulizumab-induced photosensitivity in patients with mycosis fungoides and other T-cell neoplasms

BACKGROUND

Mogamulizumab (Mog) is a defucosylated, therapeutic monoclonal antibody, targeting CCR4 and was first approved in Japan for the treatment of adult T-cell leukaemia/lymphoma (ATLL), followed by cutaneous T-cell lymphoma and peripheral T-cell lymphoma.

OBJECTIVE

To retrospectively investigate development of photosensitivity in patients with mycosis fungoides and other T-cell neoplasms after treatment with Mog.

METHODS

We treated seven cutaneous lymphoma patients with Mog. Upon combination treatment with narrow-band UVB, we noticed that four patients developed photosensitivity dermatitis following Mog therapy, including two cases of mycosis fungoides, one case of adult T-cell leukaemia/lymphoma and one case of EB virus-associated T-cell lymphoproliferative disorder. Phototest was performed with UVA and UVB, and immunohistochemical staining for CD4, CD8 and Foxp3 was conducted in both photosensitivity and lymphoma lesions.

RESULTS

Phototest revealed that the action spectrum of the photosensitivity was UVB in three cases and both UVB and UVA in one case. Histopathologically, the photosensitive lesions were characterized by a lichenoid tissue reaction with a CD8⁺ T cell-dominant infiltrate, sharing the feature with chronic actinic dermatitis, an autoreactive photodermatosis with a cytotoxic T-cell response. Foxp3⁺ regulatory T cells (Tregs) were decreased in the photosensitivity lesions compared with the lymphoma lesions.

CONCLUSION

Increased incidence of photosensitivity reaction was observed during Mog treatment. Decreased number of Tregs in the lesional skin suggests that this reaction is possibly induced by autoreactive cytotoxic T cells.

Tungsten lamp and chronic actinic dermatitis

Chronic actinic dermatitis is often associated with sensitivity to UV light. It is not well recognised that chronic actinic dermatitis may be exacerbated by light in the visible spectrum. We describe an unusual case of chronic actinic dermatitis exacerbated by a tungsten lamp, which emits light in the visible spectrum.