Acute pyoderma gangrenosum does not require surgical therapy.

Pyoderma gangrenosum is an uncommon ulcerative skin disorder that is often associated with underlying systemic diseases, the most common of which is inflammatory bowel disease. We report an illustrative case of a 36-year-old woman with pyoderma gangrenosum occurring at surgical sites and at sites of trauma. She had associated Crohn disease. Multiple surgical procedures were performed on this patient, without improvement. Pyoderma gangrenosum can mimic a necrotizing soft tissue infection. Early recognition of the characteristic lesion may prevent unnecessary operations and facilitate effective control with appropriate medical therapy.

Human herpesvirus 6 is present in lesions of Langerhans cell histiocytosis.

Langerhans cell histiocytosis (LCH) is a disease characterized by Langerhans cell infiltration of skin and bone, with its most severe form manifested by multifocal infiltration of many organs. The etiology is unknown, although viral infection has been proposed as a potential pathogenic factor. Human herpesvirus 6 (HHV-6), a recently described member of the human herpesvirus family, has been associated with atypical or malignant lymphocytic processes, and immune disorders. Based on these observations, we suspected that HHV-6 may play a role in the pathogenesis of LCH. Lesional tissue of 30 patients with LCH was retrospectively examined for the presence of HHV-6 by using the polymerase chain reaction. Tissue specimens from 63 patients with other benign and malignant histiocytic and lymphocytic diseases served as controls. In addition, all specimens were examined with control primers specific for herpes simplex virus (HSV). HHV-6 DNA was detected in lesions of 14 of 30 patients with LCH (47%). On clinical subgroup analysis, HHV-6 DNA was found in 10 of 16 patients with extraosseous disease (63%) and in four of 14 patients with disease limited to bone (29%). In each case, the prevalence of HHV-6 in LCH lesions was statistically significant, when compared to the control population. HSV DNA was not found in any of the LCH or control specimens. Although the presence of a virus alone does not establish a causal role in the disease, it supports the possibility of an etiologic relationship. From this study, we emphasize the need for further investigation of the potential HHV-6-mediated pathogenesis of LCH.

Examination of cutaneous T-cell lymphoma for human herpesviruses by using the polymerase chain reaction.

The etiology of cutaneous T-cell lymphoma remains unknown, although an association with viral infection, in particular certain retroviruses and human herpesviruses, has been suggested. The purpose of this study was to examine skin biopsies of cutaneous T-cell lymphoma for the presence of Epstein-Barr virus, herpes simplex virus type 1 and type 2, and human herpesvirus-6 by using the polymerase chain reaction. Lesional skin biopsies from 30 patients with cutaneous T-cell lymphoma were studied. Control specimens included biopsies from 9 patients with lymphomatoid papulosis and 10 patients with pityriasis lichenoides et varioliformis acuta. DNA extracted from each specimen, as well as from a known positive control for each virus, was examined by using the polymerase chain reaction with viral-specific primers. Each DNA specimen was also amplified with control primers for human beta globin. The specificity of the amplified products was confirmed by Southern analysis. Neither Epstein-Barr virus nor herpes simplex virus was detected in any of the patient specimens examined. Human herpesvirus-6 was detected in one specimen of cutaneous T-cell lymphoma and one specimen of lymphomatoid papulosis. These results do not support a role for any of these herpesviruses in the pathogenesis of cutaneous T-cell lymphoma.