The term Cutaneous Pseudolymphoma (CPL) refers to a set of diseases in which benign lymphocytic proliferations occur that simulate cutaneous lymphomas from clinical and histopathological point of view [4,5]. It consists of a benign inflammatory response triggered by anantigen that estimates the lymphomatoid response, histologically called Reactive Lymphoid Hyperplasia . Antigens involved include response to bacterial infections, contact dermatitis, pigmented lichenoid purpura, lichen sclerosus and atrophic dermatitis, stageofmorphea, lupus panniculitis, arthropodsbites, nodular sarna, medications (anticonvulsants, antidepressants, benzodiazepines, angiotens in converting enzyme inhibitors, beta-blockers, calciumchannelblockers, lipid-loweringagents, amongothers), spirochetes (Borreliaburgdorferi, Treponema pallidum) Virus, HIV andPoxvirus), mites (Sarcoptesscabei), vaccines, tattoo paints, piercing. However, most cases are considered idiopathic.2,3,4 In the case reported, the only pathology associated was grade II acne, which had not been treated with medication. There is possibility of acne and, there fore, the local bacterial infection be related to the appearance of pseudolymphoma in the case described.
The pathogenesis of CPL is still studied and it is believed that there is participation of the Skin Associated Lymphoid Tissue (SALT) and its proliferation by antigenic stimulation. This theory corroborates the progression of CPL to lymphoma due to permanent antigenic exposure, as occurs with gastric lymphomas [5,6].
Clinically, it may present as a single nodule, as observed in the case described, ormultiple, papules, infiltrated plaques, persistent erythema or exfoliative erythroderma, and it is impossible to define the diagnosis only by clinical examination of the lesions. In view of the CPL hypothesis, the lesion should be biopsied .
Histological analysisis of paramount importance in the definition of the diagnosis. There is a lymphocytic-follicular proliferation of T cells, B or the mixture of the two with macrophages and dendritic cells . The pattern of infiltration maybe nodular or epidermo tropic, and cell size is variable. Immunohistochemistry is imperative in distinguishing the infiltrate and its classification .
Therefore, the diagnosis of CPL is based on clinical history, physicalexamination, and adequate an atomopathological and immunohistochemical study. The search for causal agents, serological and contact tests are auxiliary .
As for the clinical course, it is usually variable. Some lesions regress after the biopsy, while others may persist for months to years. There may be recurrence in cases of new contact with the causative agente. Rareprogressionof CPL to cutaneous lymphoma can occur, butthe cause is not well understood. Clinical signs of alertness involve the presence of multiple lesions and lymphadenopathy .
Treatment should be considered conservative, sincemany cases regress spontaneously. Single lesions can be treated with surgical excision, topical cortico steroid and intralesional, cryotherapy. Disseminated cases can be treated with systemic cortico steroids, Interferon alfa, Hydroxychloroquine and even radiotherapy [2,4]. Removal of the causative agent, if identified, should be performed. In the case reported, the lesion regressed after partial surgical excision (biopsy) and acne treatment was instituted, aiming to control the possible triggering factor.