The human polyomavirus JCV, the etiological agent of progressive multifocal leukoencephalopathy, has been associated with primitive neuroectodermal tumors and various glial-derived tumors, including glioblastoma multiforme (GBM). Here we describe the unique clinical case of a 54-year-old man who presented with headaches, hemiparesis and drowsiness. T1 and T2 magnetic resonance images revealed a large solid tumor with a cystic component located in the right temporal lobe, with extension into the parietal lobe. Histologically, the tumor was composed of two areas, a main area of large neoplastic cells with pleomorphic atypical nuclei and abundant cytoplasm, which by immunohistochemistry was reactive for glial fibrillary acidic protein, mixed with several foci of poorly differentiated tumoral cells with elongated nuclei and scant cytoplasm, negative for GFAP, but robustly immunoreactive for synaptophysin and phosphoneurofilaments. Results from PCR in laser capture microdissected cells from both areas of the tumor revealed the presence of DNA sequences corresponding to the early, late and control regions (CR) of the JCV genome and expression of JCV proteins T-antigen and Agnoprotein in both phenotypes. No evidence for capsid protein was observed, excluding productive viral infection. Sequencing demonstrated the presence of the JCV Mad-1 strain with distinct point mutations in the CR of isolates from both, GBM and small cell architectural areas. The presence of JCV DNA sequences and expression of viral proteins further reinforces the role of the widely spread human neurotropic virus in early transformation and in the development of brain tumors.

Rarely, systemic lupus erythematosus (SLE) presents with bullous lesions due to severe edema and hydropic degeneration of the basal layer, or as a subepidermal blistering disease. Here, we describe two Mexican teenagers, one with SLE with blisters and another with bullous SLE. We also discuss the mechanisms and clinical implications of lesion formation in patients with SLE and bullae.

Formalin-fixed intestinal tissue specimens from 12 Mexican pediatric patients with intussusception were examined for the presence of adenovirus. Four patients (33%) had detectable adenovirus antigen in epithelial cells as determined by using immunohistochemical analysis. Two of the patients with positive immunohistochemical results had antigens in dendritic and mononuclear inflammatory cells, and 3 patients had positive results for species C adenovirus by in situ hybridization using adenovirus species-specific probes (A-F). A real-time polymerase chain reaction assay specific for species C (nonenteric) adenoviruses was used to confirm immunohistochemical results and to amplify adenovirus DNA for sequencing. A sequence similar to that for adenovirus serotype 1 was found in 1 patient, serotype 2 in another, and serotype 6 in a third; in the fourth patient, the sequence was indeterminate between serotypes 2 and 6. The assays used in this study proved useful for the identification of species C adenoviruses in formalin-fixed specimens from Mexican pediatric patients with intussusception.

Formalin-fixed intestinal tissue specimens from 12 Mexican pediatric patients with intussusception were examined for the presence of adenovirus. Four patients (33%) had detectable adenovirus antigen in epithelial cells as determined by using immunohistochemical analysis. Two of the patients with positive immunohistochemical results had antigens in dendritic and mononuclear inflammatory cells, and 3 patients had positive results for species C adenovirus by in situ hybridization using adenovirus species-specific probes (A-F). A real-time polymerase chain reaction assay specific for species C (nonenteric) adenoviruses was used to confirm immunohistochemical results and to amplify adenovirus DNA for sequencing. A sequence similar to that for adenovirus serotype 1 was found in 1 patient, serotype 2 in another, and serotype 6 in a third; in the fourth patient, the sequence was indeterminate between serotypes 2 and 6. The assays used in this study proved useful for the identification of species C adenoviruses in formalin-fixed specimens from Mexican pediatric patients with intussusception.

A case of a cerebral malignant triton tumor in a 3-year-old boy with a 2-month history of frontal headache and no clinical evidence of neurofibromatosis is reported. The computed tomography (CT) scan showed a large, irregular tumor in the right parietooccipital lobe. A partial surgical resection was performed. Histologically, the tumor was highly cellular and consisted of spindle cells with hyperchromatic and pleomorphic nuclei. Focally, neoplastic cells with rhabdomyoblastic features were found. The immunohistochemical study showed that tumor cells were positive for S-100 protein and CD57, and the rhabdomyoblasts expressed desmin, Myo-D1, and myoglobin. During the postoperative period, a massive intraparenchymal hemorrhage was identified and surgical drainage was performed. The patient worsened and died 10 days after the first surgery. Postmortem study was not authorized. Six cases of cerebral malignant nerve sheath tumor have been described; however, primary intraparenchymal malignant triton tumor has not been previously described.