Cytomegalovirus in colorectal cancer and idiopathic ulcerative colitis

Cytomegalovirus (CMV) is a genus in the family Herpesviridae that has been associated with gastrointestinal syndromes. In this work we looked for a possible association of CMV infection with colorectal cancer and ulcerative colitis (UC). Blood and enteric tissue samples of 14 patients with colorectal cancer and of 21 with UC were subjected to a nested-PCR that amplifies part of the gB gene of CMV and also to immunohistochemistry using a specific monoclonal antibody to IE 76kDa protein of CMV. CMV was detected by nested-PCR in the blood and/or the enteric tissue of nine (64.3 percent) colorectal cancer and 16 (76.2 percent) ulcerative colitis patients. In the immunohistochemistry it was observed that 12 (12/21, 57.1 percent) positive enteric tissue samples of patients with UC and none from patients with colorectal cancer (0/14) were positive to CMV. The positivity of CMV infections in the UC patient group (12/21, 57.1 percent) showed by both techniques, was significantly higher (p = 0.015) than that observed for colorectal cancer patients (2/14, 14.3 percent). These results suggest an association of ulcerative colitis with CMV infection of the enteric tissue.

Os Cytomegalovírus (CMV) são um gênero da família Herpesviridae, que pode estar associado a síndromes gastrointestinais. No presente trabalho buscamos uma possível associação da infecção por CMV com câncer coloretal e retocolite ulcerativa (RCU). Amostras de sangue e tecido entérico de 14 pacientes com câncer coloretal e 21 com RCU foram submetidas a uma nested-PCR que amplifica parte do gene gB do CMV e a uma imunohistoquímica utilizando um anticorpo monoclonal específico para proteína IE 76Kda de CMV. CMV foi detectado pela nested-PCR em sangue e/ou tecido entérico de 9 (64,3 por cento) dos pacientes com câncer coloretal e 16 (76,2 por cento) dos pacientes com RCU. Na imunohistoquímica foram observadas 12 (57,1 por cento) amostras positivas para CMV nos pacientes com RCU e nos pacientes com câncer coloretal o CMV não foi detectado em nenhuma amostra. A positividade das infecções no grupo de pacientes com RCU (12/21, 57.1 por cento) foi significantemente mais alta (p = 0,015) que aquela observada nos pacientes com câncer coloretal (2/14, 14.3 por cento). Estes resultados sugerem uma associação da presença de CMV no tecido entérico com RCU.

Diagnosis of cytomegalovirus infections by qualitative and quantitative PCR in HIV infected patients

A high incidence of cytomegalovirus (CMV) infections is observed in Brazil. These viruses are causatives of significant morbidity and mortality among patients with advanced human immunodeficiency virus (HIV) infection. This work, shows the application of a PCR on determination of CMV load in the buffy coat and plasma. We analyzed the samples of 247 HIV infected patients in order to diagnose CMV infection and disease. We developed a semi-quantitative PCR that amplifies part of the glycoprotein B (gB) gene of CMV. The semi-quantitative PCR was carried out only in positive clinical samples in a qualitative PCR confirmed by a nested-PCR. CD4 lymphocyte count, HIV viral load and CMV disease symptom were correlated with CMV load. CMV genome was detected in the buffy coat of 82 of 237 (34.6 percent) patients, in 10 of these the CMV load was determined varying between 928 and 332 880 viral copies/mug DNA. None of these 237 patients developed any suggestive manifestation of CMV disease. For the other 10 HIV infected patients selected based on the suspicion of CMV disease, CMV genome was detected in only one case. This patient presented a high CMV load, 8 000 000 copies/mug DNA, and developed a disseminated form of CMV disease including hepatitis and retinitis. Our results were greatly influenced by the impact of the highly active antiretroviral therapy that reduced incidence of CMV viremia and occurrence of CMV disease in the HIV infected patients