Abstract Annular elastolytic giant cell granuloma is an uncommon granulomatous cutaneous disease that usually affects sun-exposed skin. Non-scarring alopecia is a possible presentation. Although histopathology is mandatory for the diagnosis, dermoscopy may help to narrow down the clinical differential diagnosis. The authors report a case of annular elastolytic giant cell granuloma in the scalp of a female adult patient, showing multiple yellowish/orange follicular dots in a diffuse erythemato-whitish background in the dermoscopy.

Abstract Generalized eruptive keratoacanthoma of Grzybowski is a rare variant of multiple keratoacanthomas counting with about 40 cases reported. It is a chronic and progressive disease for which none of the described therapeutic options has been entirely satisfactory. We report a case of an 83-year-old female who presented with a 3-month history of extremely pruritic, multiple, skin-coloured to erythematous to brownish, millimetric papules, with a keratotic centre. Histological examination of an incisional biopsy was consistent with the diagnosis of keratoacanthoma. The patient started acitretin 25 milligrams daily with a complete resolution of pruritus and regression of numerous lesions.

RESUMO Os autores descrevem o caso de um homem de 84 anos hospitalizado por pneumonia bacteriana que foi posteriormente diagnosticado com COVID-19 e observado com exantema flexural. Com terapêutica de suporte o rash desapareceu em 7 dias e o doente recuperou completamente. Na mesma altura surgiram dois outros casos de infeção por SARS-CoV-2 na mesma enfermaria. O estudo histopatológico e imunopatológico de biópsia de pele mostrou um infiltrado inflamatório perivascular de predomínio linfoplasmocitário ligeiro na derme superficial, predominantemente CD4+, um ligeiro epidermotropismo, espongiose e paraqueratose focal, compatível com um exantema viral ou uma erupção maculopapular medicamentosa. Os autores pretendem contribuir para uma melhor compreensão das manifestações da infeção pelo SARS-CoV-2 e alertar para a importância da identificação precoce de alterações cutâneas possivelmente associadas a COVID-19.

ABSTRACT We report a case of a 84-year-old male hospitalized for bacterial pneumonia who, during hospitalization, developed a flexural exanthema in parallel with a positive swab for SARS-CoV-2. Supportive therapy was instituted, the rash disappeared in 7 days and the patient fully recovered. At the same time, two other cases of SARS-CoV-2 infection occurred in the same ward. Histopathology and immunohistochemistry of a skin biopsy showed a scarce predominantly perivascular lymphocytic infiltration in the upper dermis, predominantly by CD4+ T cells, a slight epidermotropism, spongiosis and focal parakeratosis, compatible with a viral exanthema or a maculopapular drug eruption. Patch testing with possible culprit drugs were negative. We seek to add value in understanding all the manifestations of SARS-CoV-2 infection and to draw attention to the importance of early identification of skin manifestations in association with COVID-19.

Abstract White fibrous papulosis of the neck is a rare entity, with fewer than 50 cases described. It is a benign pathology whose main interest lies in its broad differential diagnosis, especially with pseudoxanthoma elasticum. The authors report the case of a 77-year-old woman with multiple yellow-white monomorphic papules on the posterior cervical region, with years of evolution. Cutaneous biopsy revealed a nodular area in the superficial and middle reticular dermis, with slight thickening of the collagen fibers and focally enlarged elastic fibers, aspects highlighted in the Verhoeff staining that additionally showed absence of elastic fibers in the papillary dermis.

Abstract Metastatic Crohn’s disease is a rare extraintestinal manifestation of Crohn’s disease. It is characterized by polymorphic skin lesions formed by non-caseating granulomas located on anatomical sites distant from the gastrointestinal tract. We report a rare case of metastatic Crohn’s disease, simultaneously displaying multiple clinically heterogeneous cutaneous lesions, in a patient with previously diagnosed Crohn’s disease in remission due to anti-TNF-α use. This case highlights the need for high clinical suspicion and early biopsy in the setting of a patient with Crohn’s disease and persistent skin lesions, even under biologic therapy. Furthermore, it reinforces the need of monitoring of the serum level of infliximab, increasing the dose in case it is low or undetectable.

Abstract: Non-steroidal, anti-inflammatory drugs, followed by antibiotics, are the main causes of fixed drug eruption. They provoke one or several round erythematous or bullous lesions that recur in the same place after taking the causative medication. A positive patch test on residual, lesional skin can replace satisfactorily oral reintroduction. We describe the case of a 74-year-old woman with numerous, rounded, erythematous lesions on the trunk and recurrent blistering on the fifth right-hand finger, which developed a few hours after taking etoricoxib. Lesional patch testing with etoricoxib was positive and reproduced the typical pattern of a fixed drug eruption upon histopathology. We emphasize the specific reactivity of the etoricoxib patch test, and the capacity to reproduce the histologic pattern of the reaction.

Abstract: Rosai-Dorfman disease is a benign histiocytic proliferative disorder of unknown etiology. The disease mainly affects lymph node tissue, although it is rarely confined to the skin. Here, we describe a 53-year-old woman with purely cutaneous Rosai-Dorfman disease. The patient presented with a large pigmented plaque on her left leg, and sparse erythematous papules on her face and arms. A complete clinical response was achieved with thalidomide, followed by recurrence at the initial site one year later. The histological examination displayed the typical features of Rosai-Dorfman disease in the recent lesions but not in the older lesions. In the setting of no lymphadenopathy, the histopathological features of Rosai-Dorfman disease are commonly misinterpreted. Therefore, awareness of the histological aspects present at different stages, not always featuring the hallmark microscopic signs of Rosai-Dorfman disease, is particularly important for a correct diagnosis of this rare disorder.

Abstract: Background: Cancer is currently among the three leading causes of death after solid organ transplantation and its incidence is increasing. Non-melanoma skin cancer - squamous cell carcinoma and basal cell carcinoma - is the most common malignancy found in kidney transplant recipients (KTRs). The incidence of non-melanoma skin cancer in KTRs has not been extensively studied in Portugal. Objectives: To determine the incidence of non-melanoma skin cancer in KTRs from the largest Portuguese kidney transplant unit; and to study risk factors for non-melanoma skin cancer. Methods: Retrospective analysis of clinical records of KTRs referred for the first time for a dermatology consultation between 2004 and 2013. A case-control study was performed on KTRs with and without non-melanoma skin cancer. Results: We included 288 KTRs with a median age at transplantation of 47 years, a male gender predominance (66%) and a median transplant duration of 3.67 years. One fourth (n=71) of KTRs developed 131 non-melanoma skin cancers, including 69 (53%) squamous cell carcinomas and 62 (47%) basal cell carcinomas (ratio squamous cell carcinoma: basal cell carcinoma 1.11), with a mean of 1.85 neoplasms per patient. Forty percent of invasive squamous cell carcinomas involved at least two clinical or histological high-risk features. The following factors were associated with a higher risk of non-melanoma skin cancer: an older age at transplantation and at the first consultation, a longer transplant duration and the presence of actinic keratosis. KTRs treated with azathioprine were 2.85 times more likely to develop non-melanoma skin cancer (p=0.01). Conclusion: Non-melanoma skin cancer was a common reason for dermatology consultation in Portuguese KTRs. It is imperative for KTRs to have access to specialized dermatology consultation for early referral and treatment of skin malignancies.

Abstract: Benign follicular tumors comprise a large and heterogeneous group of neoplasms that share a common histogenesis and display morphological features resembling one or several portions of the normal hair follicle, or recapitulate part of its embryological development. Most cases present it as clinically nondescript single lesions and essentially of dermatological relevance. Occasionally, however, these lesions be multiple and represent a cutaneous marker of complex syndromes associated with an increased risk of visceral neoplasms. In this article, the authors present the microscopic structure of the normal hair follicle as a basis to understand the type and level of differentiation of the various follicular tumors. The main clinicopathological features and differential diagnosis of benign follicular tumors are then discussed, including dilated pore of Winer, pilar sheath acanthoma, trichoadenoma, trichilemmoma, infundibuloma, proliferating trichilemmal cyst/tumor, trichoblastoma and its variants, pilomatricoma, trichodiscoma/fibrofolliculoma, neurofollicular hamartoma and trichofolliculoma. In addition, the main syndromes presenting with multiple follicular tumors are also discussed, namely Cowden, Birt-Hogg-Dubé, Rombo and Bazex-Dupré-Christol syndromes, as well as multiple tumors of follicular infundibulum (infundibulomatosis) and multiple trichoepitheliomas. Although the diagnosis of follicular tumors relies on histological examination, we highlight the importance of their knowledge for the clinician, especially when in presence of patients with multiple lesions that may be the cutaneous marker of a cancer-prone syndrome. The dermatologist is therefore in a privileged position to recognize these lesions, which is extremely important to provide further propedeutic, appropriate referral and genetic counseling for these patients.

Abstract Cutaneous meningiomas are rare tumors most commonly located on the scalp. We report the case of a 55-year-old male who presented with a 2x3 cm tumoral lesion on the forehead. The lesion was hard, adherent and covered by normal skin. Incisional biopsy revelead a proliferation of monomorphic round cells, organized in nests and focally forming pseudovascular spaces. Immunohistochemical study revealed positivity for epithelial antigen membrane and vimentin. Vascular markers, cytokeratins and S100 protein were negative. A brain CT scan did not show any evidence of intracranial meningioma. The authors describe the case of a cutaneous frontal meningioma in probable relation with previous cranioencephalic trauma.

Abstract Multiple minute digitate hyperkeratosis is a rare, non-follicular dermatosis, with fewer than 30 cases described worldwide. It can be either acquired or inherited in an autosomal dominant pattern. We describe the case of an 83-year old patient with life-long, multiple, digitate, milimetric lesions, and a positive family history for the same dermatosis.

Líquen nítido generalizado é uma dermatose inflamatória crônica, rara, com achados histológicos muito característicos. Sua patogênese não está completamente esclarecida e, muito raramente, tem sido associado a doenças genéticas. Reportamos o caso de um doente do sexo masculino, de 12 anos de idade, com Doença de Niemann-Pick, que desenvolveu líquen nítido generalizado.

Generalized lichen nitidus is an uncommon chronic inflammatory dermatosis with very characteristic histological findings. Its pathogenesis is still unclear; very rarely it has been associated with genetic disorders. Herein we report the case of a 12-year-old boy with Niemann-Pick disease who developed generalized lichen nitidus.