Carcinoid tumors: what should increase our suspicion?

Carcinoid tumors are neuroendocrine neoplasms, primarily of the gastrointestinal tract. Their incidence has been increasing over the last 2 to 3 decades. Patients often present with vague, nonspecific symptoms. Thus, primary care physicians should keep this diagnosis in mind and start appropriate diagnostic testing if they suspect it on a clinical basis. Patients with carcinoid tumors are also at increased risk of developing other malignancies, so close follow-up by their primary care physician is necessary.

Impaired hepatitis C virus (HCV)-specific effector CD8+ T cells undergo massive apoptosis in the peripheral blood during acute HCV infection and in the liver during the chronic phase of infection.

A majority of patients infected with hepatitis C virus (HCV) do not sustain an effective T-cell response, and viremia persists. The mechanism leading to failure of the HCV-specific CD8(+) T-cell response in patients developing chronic infection is unclear. We investigated apoptosis susceptibility of HCV-specific CD8(+) T cells during the acute and chronic stages of infection. Although HCV-specific CD8(+) T cells in the blood during the acute phase of infection and in the liver during the chronic phase were highly activated and expressed an effector phenotype, the majority was undergoing apoptosis. In contrast, peripheral blood HCV-specific CD8(+) T cells during the chronic phase expressed a resting memory phenotype. Apoptosis susceptibility of HCV-specific CD8(+) T cells was associated with very high levels of programmed death-1 (PD-1) and low CD127 expression and with significant functional T-cell deficits. Further evaluation of the "death phase" of HCV-specific CD8(+) T cells during acute HCV infection showed that the majority of cells were dying by a process of cytokine withdrawal, mediated by activated caspase 9. Contraction during the acute phase occurred rapidly via this process despite the persistence of the virus. Remarkably, in the chronic phase of HCV infection, at the site of infection in the liver, a substantial frequency of caspase 9-mediated T-cell death was also present. This study highlights the importance of cytokine deprivation-mediated apoptosis with consequent down-modulation of the immune response to HCV during acute and chronic infections.

Celiac disease: more common than you think.

Celiac disease--a chronic immune-mediated disorder primarily affecting the gastrointestinal tract--is being increasingly recognized, but because half of all cases present atypically or silently, awareness needs to be high, especially in primary care. The diagnosis is based on clinical suspicion combined with laboratory testing and can be established by a primary physician. Early diagnosis will likely improve outcome. A gluten-free diet is necessary but difficult to follow, and patients are more likely to adhere to it if a dietician and support group are involved.

Liver-infiltrating lymphocytes in chronic human hepatitis C virus infection display an exhausted phenotype with high levels of PD-1 and low levels of CD127 expression.

The majority of people infected with hepatitis C virus (HCV) fail to generate or maintain a T-cell response effective for viral clearance. Evidence from murine chronic viral infections shows that expression of the coinhibitory molecule PD-1 predicts CD8+ antiviral T-cell exhaustion and may contribute to inadequate pathogen control. To investigate whether human CD8+ T cells express PD-1 and demonstrate a dysfunctional phenotype during chronic HCV infection, peripheral and intrahepatic HCV-specific CD8+ T cells were examined. We found that in chronic HCV infection, peripheral HCV-specific T cells express high levels of PD-1 and that blockade of the PD-1/PD-L1 interaction led to an enhanced proliferative capacity. Importantly, intrahepatic HCV-specific T cells, in contrast to those in the periphery, express not only high levels of PD-1 but also decreased interleukin-7 receptor alpha (CD127), an exhausted phenotype that was HCV antigen specific and compartmentalized to the liver, the site of viral replication.

Nocturnal hydration--an effective modality to reduce recurrent abdominal pain and recurrent pancreatitis in patients with adult-onset cystic fibrosis.

Recurrent abdominal pain and recurrent pancreatitis are common problems associated with some patients with cystic fibrosis (CF). There is no known effective method to prevent recurrent abdominal pain and recurrent pancreatitis in such patients. The objective of this study was to determine whether nocturnal hydration (NH) prevents recurrent abdominal pain and recurrent acute pancreatitis in patients with adult-onset CF. Adult CF patients who were referred to our Pancreatic Diseases Clinic for recurrent abdominal pain and pancreatitis were enrolled in the study. Each patient was encouraged to drink plenty of water during the night and established a 6-month diary (3 months before and 3 months after NH was initiated), recording the frequency and severity of their abdominal pain, the amount of pain medication taken, and the volume of their water intake. We also reviewed the number of doctor's clinic visits, emergency room visits, and hospitalizations for about 1 year before and 1 year after the initiation of the NH. The frequency and the severity of abdominal pain in this group of patients were significantly reduced. The amount of pain medication and the number of emergency room visits and hospitalizations for abdominal pain and acute pancreatitis were reduced. NH is a simple and cost-effective method to prevent recurrent abdominal pain and pancreatitis in patients with adult-onset CF.