Giant sigmoid diverticulum: case report and review of the literature.

Giant colonic diverticulum is a rare entity first described in 1946 by Bonvin and Bonte. It may be congenital or acquired and the average age of presentation is 65. There are less than 150 reported cases in the literature. A large abdominal mass was detected during a routine physical examination in an 82-year-old man. CT scan showed a large air-filled mass, barium enema showed multiple sigmoid diverticula, but no communication with the mass was found. A diagnosis of giant sigmoid diverticulum was made, elective sigmoidectomy and resection of the diverticulum was performed with no complications. The clinical picture may be different, varying from asymptomatic to acute abdomen, intestinal perforation or fistula. It can be diagnosed with abdominal X-ray, CT scan, barium enema or MRI, but colonoscopy is not effective. There are two accepted theories of the pathophysiology of this entity: first, a congenital origin and second, that inflammatory diverticula are caused by a perforation with a ball-valve that allows gas to enter, but not to leave the cyst, thus, enlarging the false diverticulum, and progressively destroying the bowel layers, causing secondary fibrosis. Elective treatment is a segmental resection of the affected colon with the diverticulum and in cases of acute abdomen two-stage bowel resection is preferred.

Expression of cyclooxygenase type 2 in lepromatous and tuberculoid leprosy lesions.

BACKGROUND: Leprosy is an infectious disease with two polar forms, tuberculoid leprosy (TL) and lepromatous leprosy (LL), which are dominated by T-helper (Th) 1 and Th2 cells, respectively. High concentrations of prostaglandin E2 produced by the inducible enzyme cyclooxygenase type 2 (COX-2) in LL could inhibit Th1 cytokine production, contributing to T-cell anergy. OBJECTIVES: To compare the COX-2 expression in LL and TL. METHODS: Skin biopsies from 40 leprosy patients (LL, n = 20; TL, n = 20) were used to determine by immunohistochemistry and automated morphometry the percentage of COX-2 immunostained cells. RESULTS: Most COX-2-positive cells were macrophages; their percentages in the inflammatory infiltrate located in the papillary dermis, reticular dermis and periadnexally were significantly higher in LL than TL (P < 0.001 by Student's t-test). CONCLUSIONS: The high expression of COX-2 in LL may be related to high prostaglandin production contributing to T-cell anergy.

Expression of transforming growth factor-beta isoforms and their receptors in lepromatous and tuberculoid leprosy.

Leprosy is an infectious disease with two polar forms, tuberculoid leprosy (TT) and lepromatous leprosy (LL), that are characterized by strong cell-mediated immunity (CMI) and CMI anergy, respectively. Transforming growth factor-beta (TGF-beta) belongs to a family of pleiotropic cytokines (TGF-beta1, TGF-beta2 and TGF-beta3) that participate in the control of cell differentiation and proliferation, as well as tissue repair. This cytokine family is unique because it suppresses CMI. In this study, we compared the expression of the three TGF-beta isoforms and their receptors in skin biopsies from LL and TT patients (LL = 20; TT = 20) using immunohistochemistry and automated morphometry. The percentage of cells immunostained for the three TGF-beta isoforms and cells positive for the three TGF-beta receptors in the inflammatory infiltrate located in the papillary dermis, reticular dermis and periadnexal tissue were significantly higher in LL than that in TT, with macrophages being the most common and strongest immunoreactive cells. Some lymphocytes, fibroblasts, keratinocytes and epithelial cells from sweat glands and hair roots were also positive. In situ reverse-transcription polymerase chain reaction corroborated the capacity of these cells to synthesize TGF-beta1 and TGF-beta receptor 2. This high expression of TGF-beta isoforms and their receptors could contribute to CMI anergy and other clinical characteristic features of leprosy, like skin atrophy.

Expression of transforming growth factor-beta isoforms and their receptors in lepromatous and tuberculoid leprosy

Leprosy is an infectious disease with two polar forms, tuberculoid leprosy (TT) and lepromatous leprosy (LL), that are characterized by strong cell-mediated immunity (CMI) and CMI anergy, respectively. Transforming growth factor-beta (TGF-beta) belongs to a family of pleiotropic cytokines (TGF-beta1, TGF-beta2 and TGF-beta3) that participate in the control of cell differentiation and proliferation, as well as tissue repair. This cytokine family is unique because it suppresses CMI. In this study, we compared the expression of the three TGF-beta isoforms and their receptors in skin biopsies from LL and TT patients (LL = 20; TT = 20) using immunohistochemistry and automated morphometry. The percentage of cells immunostained for the three TGF-beta isoforms and cells positive for the three TGF-beta receptors in the inflammatory infiltrate located in the papillary dermis, reticular dermis and periadnexal tissue were significantly higher in LL than that in TT, with macrophages being the most common and strongest immunoreactive cells. Some lymphocytes, fibroblasts, keratinocytes and epithelial cells from sweat glands and hair roots were also positive. In situ reverse-transcription polymerase chain reaction corroborated the capacity of these cells to synthesize TGF-beta1 and TGF-beta receptor 2. This high expression of TGF-beta isoforms and their receptors could contribute to CMI anergy and other clinical characteristic features of leprosy, like skin atrophy.

Dengue virus in the brain of a fatal case of hemorrhagic dengue fever.

Neurologic complications associated with dengue fever are in general unusual. However, recent reports evidence more frequent neurologic alterations. In Mexico, neurologic involvement has not been reported in dengue cases. This report demonstrates the detection of dengue virus in the brain of a fatal case of dengue hemorrhagic fever. Serotype 4 was detected by immunohistochemistry and by RT-PCR in the inferior olivary nucleus of medulla and in the granular layer of cerebellum. Immunoreactivity was observed in neurons, astrocytes, microglia and endothelial cells. Our results emphasize the importance of neurologic manifestations in patients with dengue fever.