Koebner phenomenon induced by the use of a computer mouse in an occupational setting: case report.

Occupational activities are well-known triggers for the onset or aggravation of several dermatoses. The Koebner phenomenon is characterized by the appearance of cutaneous lesions typical of a given inflammatory dermatosis in an area where the skin was injured by mechanical, chemical, or biological agents. Although it is usually easily identified when associated to significant trauma, the Koebner phenomenon may go unnoticed when a small-scale injury underlies its pathogenesis. Herein, we report a case of Koebner phenomenon induced by the repetitive use of a computer mouse in an occupational setting, leading to recalcitrant psoriatic lesions on the palm of the right hand. When atypical features or unexpected poor responses to treatment are observed in skin conditions, a complete social and occupational anamnesis is paramount to identify aggravating factors and allow successful patient management.

Acquired perforating dermatosis: clinicopathologic study of a 10-year period at a tertiary teaching hospital.

BACKGROUND: Acquired perforating dermatosis (APD) comprises an uncommon group of skin disorders that develop in adulthood in association with systemic diseases. The aim of this study was to characterize clinicopathologic features and treatment outcomes in a series of patients diagnosed with APD. METHODS: Retrospective study of all patients diagnosed with an APD over a 10-year period (2009-2018) at a tertiary teaching hospital in Lisbon, Portugal. RESULTS: Fifty-seven patients with APD were identified. Thirty-five patients presented lesions in multiple anatomic areas (61.4%), and the lower limbs were the most common location. Forty-six patients reported pruritus (80.7%), which was classified as severe in 21 of them (36.8%). An underlying systemic disease was identified in 53 patients (93.0%). Diabetes mellitus (DM) and chronic kidney disease (CKD) were the most common associated systemic diseases, but psychiatric disorders, malignancies, and chronic infections were present in a significant number of patients. The combination of topical steroids with antihistamines was the most prescribed initial treatment, but only 37.8% of the patients had a complete response. Acitretin, systemic steroids, and phototherapy were the treatments associated with the best outcome. CONCLUSION: Acquired perforating dermatosis can be associated with many systemic disorders that have pruritus as a common factor. Chronic viral infections and an occult malignancy should be sought, particularly in the absence of DM and CKD. The management of APD is challenging and is best achieved with the control of the underlying systemic diseases.

Agminated Clear Cell Tumor: An Impostor of PEComa and Distinctive Dermal Clear Cell Mesenchymal Neoplasm.

Cutaneous clear cell tumors are a heterogeneous group of cutaneous neoplasms, which may show a wide range of histogenesis. We report the clinicopathological features of an agminated clear cell tumor, arising in a 67-year-old man, otherwise asymptomatic, with distinct histopathological and immunohistochemical features, which did not fit into any existing diagnostic categories. The patient presented with several skin-colored papules at the lateral and posterior aspects of the neck, which on histopathological examination showed circumscribed lobular aggregates of clear cells within the dermis. The immunohistochemical marker panel performed showed diffuse expression of vimentin, NKI-C3, and CD64 while revealing marked negativity for factor XIIIa, CD10, CD13, CD14, CD34, CD68, CD163, lysozyme, HMB45, Renal Cell Carcinoma antigen, calponin, h-caldesmon, Anti-alpha smooth muscle actin antibody [1 A4], S100, and pancytokeratin, leading the authors to postulate a monocytic origin.

Multifocal primary cutaneous extranodal NK/T lymphoma nasal type.

Nasal type extranodal NK/T-cell lymphoma is a distinct entity according to the World Health Organization classification. Although 60% to 90% of patients with this disease present with a destructive mass in the midline facial tissues, it may also primarily or secondarily involve extranasal sites, like the skin. We report the case of a 77-year-old patient that came to our department with erythematous plaques of the right leg and eczematous lesions of the trunk. These lesions were biopsied and the patient was diagnosed with extranodal NK/T-cell lymphoma, nasal type. He was treated with multi-agent systemic chemotherapy but died 5 months after diagnosis. This case highlights the rarity and variability of cutaneous features of this disease and its aggressive course and poor prognosis.

Multifocal primary cutaneous extranodal NK/T lymphoma nasal type

Abstract Nasal type extranodal NK/T-cell lymphoma is a distinct entity according to the World Health Organization classification. Although 60% to 90% of patients with this disease present with a destructive mass in the midline facial tissues, it may also primarily or secondarily involve extranasal sites, like the skin. We report the case of a 77-year-old patient that came to our department with erythematous plaques of the right leg and eczematous lesions of the trunk. These lesions were biopsied and the patient was diagnosed with extranodal NK/T-cell lymphoma, nasal type. He was treated with multi-agent systemic chemotherapy but died 5 months after diagnosis. This case highlights the rarity and variability of cutaneous features of this disease and its aggressive course and poor prognosis.

Kaposi's sarcoma presenting as violaceous macules on the chest of a kidney transplanted patient.

Organ transplant recipients have a high incidence of cancer associated with persistent viral infections, such as human herpes virus 8. This virus is associated with Kaposi's sarcoma, and a change in the dose or type of immunosuppression regimen should be the first step in its treatment. A multidisciplinary approach with nephrologists, dermatologists and oncologists is necessary for the management of this disease. We report a clinical case with atypical presentation and discuss the treatment options.

Bullous hemorrhagic dermatosis induced by enoxaparin.

The bullous hemorrhagic dermatosis induced by enoxaparin is a rare adverse reaction, which may be under-reported given its favorable evolution. We report a 71-year-old man who developed hemorrhagic bullae at sites distant from subcutaneous enoxaparin injections. It is important that clinicians be aware of the different adverse reactions of these widely used drugs.

Bacillary angiomatosis in a HIV-positive patient with poor adherence to antiretroviral therapy.

Bacillary angiomatosis is a systemic disease caused by Bartonella (B.) henselae and B. quintana. Today it is a rare disease that occurs predominantly in patients with poor adherence to antiretroviral therapy or with late diagnosis of human immunodeficiency virus (HIV). We report on the case of a 40-year-old Caucasian female with HIV-1 and hepatitis B virus (HBV) co-infection diagnosed 17 years ago. She presented to the emergency department with an erythematous, painless nodule located on the left naso-genian fold. In the next few weeks the disease disseminated to the oral and left tarsal mucosa and to the palm of the left hand. The histopathological findings were suggestive of bacillary angiomatosis which was confirmed by polymerase chain reaction (PCR). The patient was treated with clarithromycin 500 mg bid per os for 3 months, with complete remission of the mucocutaneous lesions. Bacillary angiomatosis is a potentially fatal disease. Early diagnosis and treatment are critical in reducing the morbidity and mortality associated with it.