Milker's nodule is an occupational viral skin disease of universal distribution, caused by the Paravaccinia virus and that occurs in individuals who deal with dairy cattle herds. We describe a case acquired due to lack of use of PPE (Personal Protective Equipment) and perform a literature review.

Leprosy is a chronic disease characterized by manifestations in the peripheral nerves and skin. The course of the disease may be interrupted by acute phenomena called reactions. This article reports a peculiar case of type 2 leprosy reaction with Sweet's syndrome-like features as the first clinical manifestation of leprosy, resulting in a delay in the diagnosis due to unusual clinical presentation. The patient had clinical and histopathological features reminiscent of Sweet's syndrome associated with clusters of vacuolated histiocytes containing acid-fast bacilli isolated or forming globi. Herein, it is discussed how to recognize type 2 leprosy reaction with Sweet's syndrome features, the differential diagnosis with type 1 leprosy reaction and the treatment options. When this kind of reaction is the first clinical presentation of leprosy, the correct diagnosis might be not suspected clinically, and established only with histopathologic evaluation.

In the past decades, there was a considerable advance in regard to recognition of morphologic findings and classification of several benign and malignant vascular proliferations. In 2002, attention was called by Requena et al to a new variant of cutaneous hemangioma named acquired elastotic hemangioma. In this article, a case of acquired elastotic hemangioma is reported with documentation of clinical, dermatoscopic, histopathological, and immunohistochemical findings. A systematic review of the previously 49 reported cases is provided. The criteria for clinical and histopathological diagnosis are highlighted.

The use of lasers and intense pulsed light (IPL) technology has become an established practice in dermatology and aesthetic medicine. The use of laser therapy and IPL in the treatment of pigmented melanocytic lesions is a controversial issue. We report clinical, dermoscopic and histological changes of a completely regressed pigmented melanocytic nevus after hair removal treatment with the LightSheer™ Diode Laser (Lumenis Ltd, Yokneam, Israel).

Pityriasis Amiantacea, also known as pseudotinea amiantacea, is a clinical syndrome which affects the scalp, having a reaction pattern reported to occur in several inflammatory dermatoses. The authors seek to establish the correlation between its clinical, dermoscopic and light microscopy features through the analysis of scale-encrusted hair tufts submitted to histological processing. Keywords: Dermatitis, seborrheic; Dermoscopy; Pityriasis; Psoriasis; Tinea Resumo: A pitiríase amiantácea, também chamada de pseudotínea amiantácea, é compreendida como uma síndrome clínica que acomete o couro cabeludo. Representa um padrão de reação a diversas dermatoses inflamatórias. Os autores procuram estabelecer a correlação entre características clínicas, dermatoscópicas e de microscopia ótica, através da análise do tufo de cabelos agregados pelas escamocrostas, submetido a processamento histológico.

A 17-year-old male presented for dermatologic consultation with slightly elevated reddish papules covered by yellowish scales in the scalp for the last two years and reddish and indurated ulcers in the perineum lasting six months. Additional complaints included polyuria, polydipsia, delay in the development of secondary sexual characteristics and hearing loss of the right ear secondary to a medium otitis. Lesions from scalp and perineum were sampled for histopathologic examination and revealed a dense cellular infiltrate made up of mononuclear cells with conspicuous eosinophilic cytoplasm and large cleaved vesicular nucleus, some of them with shapes resembling the format of a kidney and others reminiscent of coffee beans. Numerous intermingling eosinophils were present. The diagnosis of Langerhans cell histiocytosis was then rendered and confirmed by positive immunostaining of neoplastic cells for anti-CD1a and anti-S100 protein antibodies. The work-up revealed diabetes insipidus, hypogonadotropic hypogonadism, hiperprolactenemia, growing-hormone deficiency and thickness of the pituitary stalk. The patient was treated with prednisone and vinblastin based chemotherapy regimen for six months with complete remission, but presented recurrence of some lesions in the scalp, which were handled with topical mustard and corticosteroids. After chemotherapy, the endocrinologic disturbances were corrected with hormonal replacement therapy. The patient is currently in good health with a follow-up of five years. abstRaCt

Pseudocarcinomatous hyperplasia (PCH) is a benign reactive epithelial proliferation that may be associated to lymphomas of the skin or external mucous membranes. We present a case of single lesion mycosis fungoides (Woringer-Kollop's reticulosis pagetoid) associated with PCH that was initially misdiagnosed as squamous cell carcinoma (SCC) and review all PubMed-indexed previously reported cases on lymphomas of the skin or external mucous membranes associated to PCH, SCC, and keratoacanthomas. Including our own case, we collected data of 114 cases of cutaneous or mucosal lymphoproliferative disorders associated to PCH, 3 cases associated to SCC, and other 3 cases associated to keratoacanthomas. All cases were tabulated to the following parameters whenever data was available: sex, age, previous medical conditions, number of lesions (single × multiple), site of involvement (mucosa, skin or both), clinical impression, initial equivocal histopathologic diagnosis, final diagnosis, keratinocytic atypia (presence × absence), lymphocytic atypia (presence × absence), CD30-status, and treatment.

Onychocytic matricoma is a newly described tumor of the nail matrix. Clinically, it presents with localized thickening of the nail plate and melanonychia. Histologically, it represents a benign acanthoma of onychocytes. There are 8 cases reported in the literature. A 12-year-old girl presented with localized melanonychia and concurrent thickening of the nail plate restricted to the area of pigmentation affecting the right thumb, with no history of trauma or pain. We report a case of this rare tumor occurring in late childhood and provide a comprehensive review of its clinical presentation and differential diagnosis. Both clinicians and dermatopathologists should be aware of the presentation of onychocytic matricoma and include it in their scope of diagnosis of longitudinal nail bands.