In 1996 the prevalence, risk factors, and genotype distribu-subject (0.7%), type 2c in 66 subjects (44.6%), type 3a in 4 subjects (2.7%), and type 4 in two subjects (1.3%). These tion of hepatitis C virus (HCV) infection were assessed in the general population of a town in southern Italy. The sample figures differ from those of Italian patients with chronic liver disease in whom genotype 2 is more rare. None of the individwas selected from the census by a systematic 1:4 sampling procedure. The participation rate was 96.6%. Among the uals was infected with more than one genotype. The distribution of the two most common HCV viral types (1b and 2c) 1,352 subjects enrolled, 195 (14.4%) tested reactive to antibody to HCV (anti-HCV) with enzyme immunoassay (EIA was not statistically different in terms of mean age, sex, or risk factors and suggests that they may have had a parallel 3). When further tested with recombinant immunoblot assay (RIBA 3), 170 subjects (87.2%) tested positive, 23 subjects spread in this community. These findings provide one of the highest overall anti-HCV prevalence rates in a general popula-(11.8%) had indeterminate results, and 2 subjects (1%) tested negative. Thus, the overall anti-HCV EIA-positive RIBA-con-tion with a likely cohort effect, i.e., decreased risk of infection along generations. These observations may indicate an epifirmed prevalence was 12.6% (170 of 1,352 subjects) and increased from 1.3% in subjects younger than 30 years to demic or focus of hepatitis C that occurred several years earlier. The majority of anti-HCV-positive subjects in the 33.1% in those ¢60 years of age. This latter age group accounted for 72.3% of all anti-HCV-positive subjects. Females oldest age group and with no clinical evidence suggests that HCV infection is a very prolonged and indolent disease. tested positive more frequently than males (14.1% vs. 10.5%; P õ .05). Alanine transaminase (ALT) concentrations were (HEPATOLOGY 1997;26:1006-1011.) abnormal in only 4.1% (7/170) of anti-HCV EIA-positive RIBA-confirmed subjects. This suggests that ALT screening Hepatitis C virus (HCV) infection represents a major is not useful in the detection of anti-HCV-positive subjects health problem in Italy. It has been found to be highly prevain a general population. The results of multiple logistic regreslent in subjects with chronic liver disease 1-2 and strongly sion analysis showed that an age of less than 45 years, the associated with hepatocellular carcinoma. 3-4 use of glass syringes, and dental therapy were all independent General population surveys in different countries that depredictors of anti-HCV positivity. HCV RNA was detected by termined the prevalence of hepatitis C virus antibodies (antipolymerase chain reaction in 75.9% of the 195 anti-HCV EIA-HCV) have mainly consisted of voluntary or paid blood positive subjects: in 84.7% (144/170) of the RIBA-confirmed donors. Because these populations usually have special charsubjects; in 17.4% (4/23) tested as RIBA indeterminate; and acteristics regarding age, ...

Bartonella quintana is a gram-negative microorganism that causes trench fever and chronic bacteremia. B. quintana lipopolysaccharide (LPS) was unable to induce the production of proinflammatory cytokines in human monocytes. Interestingly, B. quintana LPS is a potent antagonist of Toll-like receptor 4 (TLR4), as it inhibited both mRNA transcription and the release of tumor necrosis factor alpha, interleukin 1␤ (IL-1␤), and IL-6 by Escherichia coli LPS in human monocytes, at ratios ranging from 1,000:1 to 10:1 (B. quintana LPS to E. coli LPS). Likewise, B. quintana LPS blocked the interaction of E. coli LPS with TLR4 in transfected cell lines. The extent of the inhibitory effect of B. quintana LPS was demonstrated in microarray studies, which showed downregulation of practically all genes induced by LPS in monocytes. Because of the role of TLR4 in inflammation, B. quintana LPS may prove useful as a potent anti-TLR4 agent with therapeutic potential in both infections and autoimmune inflammation.Bartonella quintana is a gram-negative pathogen initially described during World War I as the agent of trench fever, a disease associated with recurrent fever and headaches. In the past few decades, B. quintana infection has been identified in homeless people (4). While most individuals with B. quintana infection recover, some 5 to 10% eventually develop chronic bacteremia (4) and subsequent complications, such as chronic endocarditis in the absence of preexisting heart valve lesions (20). New manifestations of B. quintana infections, such as bacillary angiomatosis, bacillary peliosis hepatitis, and chronic lymphadenopathy, have also been described (2). These manifestations have been attributed to proliferative and antiapoptotic effects of Bartonella spp. (6).A characteristic of B. quintana bacteremia is the absence of symptoms of high fever and signs of septic shock, disseminated intravascular coagulation, or organ failure. Lipopolysaccharide (LPS, or endotoxin) is a main component of the outer membranes of gram-negative microorganisms, and the LPSs from gram-negative enteric bacteria (such as Escherichia coli and Salmonella enterica) are able to induce proinflammatory cytokines, chemokines, and adhesion molecules (23) and thereby to evoke the clinical signs of sepsis. The lipid A moiety of LPS interacts with a membrane receptor complex containing Tolllike receptor 4 (TLR4), and CD14 (17,19,23). Because of strong proinflammatory effects of most species of LPS, the apparent absence of sepsis syndrome in patients with B. quintana bacteremia is a puzzling aspect of the infection. As an explanation, overproduction of the anti-inflammatory cytokine interleukin-10 (IL-10) and an attenuated inflammatory cytokine profile during B. quintana bacteremia have been proposed (5), but the molecular mechanisms have remained elusive.Recently, the LPS of the related organism Bartonella henselae was purified and characterized as a penta-acylated deep-rough LPS with low endotoxic activity (17,27). In the present study, we investigated the bio...

In patients on chronic dialysis treatment CRP is independently associated to carotid atherosclerosis and appears at least in part to be explained by IgG anti-Chlamydia pneumoniae antibodies level. These data lend support to the hypothesis that inflammation plays a role in the pathogenesis of atherosclerosis in these patients.

In this consecutive series, diagnosis of G. lamblia infection accounted for 6.5% of patients with IBS and dyspepsia. Duodenal biopsies for diagnosis of giardiasis may be unnecessary if stool sample examination is performed.

The human virome comprises viruses that infect host cells, virus-derived elements in our chromosomes, and viruses that infect other organisms, including bacteriophages and plant viruses. The development of high-throughput sequencing techniques has shown that the human gut microbiome is a complex community in which the virome plays a crucial role into regulation of intestinal immunity and homeostasis. Nevertheless, the size of the human virome is still poorly understood. Indeed the enteric virome is in a continuous and dynamic equilibrium with other components of the gut microbiome and the gut immune system, an interaction that may influence the health and disease of the host. We review recent evidence on the viruses found in the gastrointestinal tract, discussing their interactions with the resident bacterial microbiota and the host immune system, in order to explore the potential impact of the virome on human health.