J Cutan Pathol 2007: 34: 558–564 doi: 10.1111/j.1600-0560.2006.00652.x Blackwell Munksgaard. Printed in Singapore Copyright # Blackwell Munksgaard 2006 Journal of Cutaneous Pathology Lupus erythematosus: Clinical and histopathological study of oral manifestations and immunohistochemical profile of the inflammatory infiltrate Background: Lupus erythematosus (LE) is a multifactorial autoimmune disease, which may affect the oral mucosa in either its cutaneous and systemic forms, with varied prevalence. Methods: Forty-six patients with confirmed diagnosis of LE, presenting oral lesions were included in the study. Oral mucosal lesions were analyzed clinically, their histopathological features were investigated and inflammatory infiltrate constitution was assessed using immunohistochemistry against the following clusters of differentiation: CD3, CD4, CD8, CD20, CD68 and CD1a. Results: From 46 patients with specific LE oral lesions 34 were females (25 with cutaneous LE and nine with systemic LE) and 12 were males (11 with cutaneous LE and one with systemic LE). Clinical aspects of lesions varied, and lips and buccal mucosa were the most affected sites. Histologically, lesions revealed lichenoid mucositis with perivascular infiltrate and thickening of basement membrane. Inflammatory infiltrate was predominantly composed by T lymphocytes of the CD4 subtype, with a minor prevalence of B lymphocytes, isolated macrophages and rare Langerhans cells. Conclusions: Oral lesions of lupus erythematosus show a variety of clinical aspects and histologically consist of a lichenoid mucositis with deep inflammatory infiltrate, composed predominantly of T CD4 positive lymphocytes. Lourenc xo SV, de Carvalho FRG, Boggio P, Sotto MN, Vilela MAC, Rivitti EA, Nico MMS. Lupus erythematosus: Clinical and histopathological study of oral manifestations and immunohistochemical profile of the inflammatory infiltrate. J Cutan Pathol 2007; 34: 558–564. # Blackwell Munksgaard 2006. Silvia V. Lourenc xo, Fabio R. G. de Carvalho, Paula Boggio, Mirian N. Sotto, Maria A. C. Vilela, Evandro A. Rivitti and Marcello M. S. Nico Department of Dermatology, Medical School, University of Sa ˜o Paulo, Brasil Silvia V. Lourenc xo DDS, PhD, Instituto de Medicina Tropical de Sa ˜o Paulo, Laborato ´rio de Imunopatologia, Av. Dr. Ene ´as de Carvalho Aguiar, 500, 2° andar, CEP: 05403-000, Sa ˜o Paulo, SP, Brazil Tel/Fax: 155 11 3061 7065 e-mail: sloducca@usp.br Accepted for publication July 19, 2006 Lupus erythematosus (LE) is a chronic inflammatory condition, considered the prototype of autoimmune human disease. Its cause is still unknown and genetic, immunologic, hormonal and environmental factors have been implicated in its pathogenesis. The disease is more prevalent amongst women of childbearing age, although it can affect both sexes equally at any age. Classically, LE has been subdivided into a systemic and a cutaneous form. While systemic lupus erythematosus (SLE) is a multiorgan disease with variable prognosis, cutaneous lupus erythematosus (CLE) is a more 558