Biomedical subjects

V J Navarro

Publications and source records attributed to V J Navarro.

9 recordsLinked to original sources

PubMed2006

Management of patients with chronic hepatitis C infection.

Chronic infection with hepatitis C virus (HCV) is a leading cause of liver-related morbidity and mortality throughout the world. Although reliable figures regarding the global prevalence of HCV infection are wanting, it is likely that HCV prevalence will continue to increase. Injection drug use is the most important source of HCV transmission in the developed world, while unsafe therapeutic injection is an important source of transmission in developing nations. The majority of exposed individuals become chronically infected, of whom 50% develop chronic liver injury. Cirrhosis and hepatocellular carcinoma can arise in those chronically infected over a mean of 20-30 years. Despite this high prevalence and morbidity, recommendations regarding who to screen by antibody testing remain disparate. Quantitative measurement of HCV RNA and HCV genotyping is useful in predicting response to antiviral therapy. Noninvasive methods of detecting liver injury, such as serologic batteries, have not been as informative or predictable as liver biopsy. The current pharmacologic standard of care for chronic HCV infection is the combination of subcutaneous peginterferon and oral ribavirin, which yields sustained virologic response in 54%-56%. Higher rates of SVR are seen in those patients who are infected with HCV genotypes 2 and 3. As intravenous drug use remains the most important source of HCV transmission in the US and Europe, education within this group is an important preventive tool.

Antiviral Agents↗

PubMed2005

Geospatial analysis of hepatitis C in Connecticut: a novel application of a public health tool.

OBJECTIVES: This study aimed to use geographic information systems (GIS) that facilitate analysis of associations between location, environment and disease to document the non-random distribution of hepatitis C, identify infection cluster areas, and describe the demographic characteristics of those areas. METHODS: Spatial analysis was conducted of newly reported positive hepatitis C test results using the Connecticut Hepatitis C Reporting Database. A complete database of unduplicated hepatitis C laboratory reports that were sent to the Connecticut Department of Public Health during 1999 was created. Spatial filtering was used to eliminate random noise generated by sparsely populated towns or small number of cases per town. Cluster analysis was used to determine whether cases of hepatitis C virus (HCV) infection tend to occur closer in space to other cases than would be expected by chance alone. The demographic attributes of identified clusters of HCV-positive reports were examined. RESULTS: Areas with the highest concentration of HCV reports roughly correspond to the major metropolitan areas of Connecticut. Six significant clusters of HCV reports were identified in Connecticut. Four of the six clusters identified were located in the most densely populated and most urban areas of the state. All but one identified cluster had been described previously as areas of substantial injection drug use, as indicated by their designation as five of the sites of syringe exchange programmes in Connecticut. This finding suggests that geospatial analysis may assist in the identification of clusters that would not otherwise be suspected based on local demographics or other characteristics. CONCLUSIONS: These findings contribute significantly to the understanding of the state-specific epidemiology of HCV infection. This methodology can be applied wherever a similar database exists to enable the implementation of targeted prevention and educational campaigns to raise awareness of HCV risk factors, the importance of being tested, and treatment options.

Cluster Analysis↗

PubMed2001

Concise review of the management of hepatitis C.

Hepatitis C is the most common blood-borne infection in the US affecting at least 2.7 million Americans today. The majority of infected patients remain asymptomatic until the end-stages of the disease, making the infection difficult to identify, study, and treat.

Antiviral Agents↗

PubMed1998

A pilot study of soluble adhesion molecules as surrogate markers for acute liver allograft rejection.

BACKGROUND: Tissue endothelial adhesion molecule expression is increased during acute liver allograft rejection. Soluble forms exist, but their correlation to rejection and their clinical value have not been determined. METHODS: We studied endothelial adhesion molecule tissue expression and soluble levels in blood and bile and correlated these to the clinical course of 11 adult patients followed for 30 consecutive days after liver transplantation. RESULTS: Three biopsies showing acute rejection demonstrated increased intercellular adhesion molecule (ICAM)-1 but not endothelial leukocyte adhesion molecule-1 expression on hepatic endothelial cells during rejection. Vascular cell adhesion molecule (VCAM)-1 staining was focally increased in two of three specimens. Levels of soluble ICAM-1 or soluble VCAM-1 by ELISA did not distinguish acute rejection from nonrejection conditions. CONCLUSION: We confirmed that endothelial ICAM-1 expression is more intense in rejecting allografts and is more sensitive than changes in VCAM-1 or endothelial leukocyte adhesion molecule-1. However, soluble adhesion molecule determination was not useful in the accurate detection of acute rejection.

Adult↗

PubMed1997

Immunology of liver transplantation: clinical management aspects.

Orthotopic liver transplantation has developed into the treatment of choice for many patients who develop complications of end-stage liver disease. With improvements in surgical technique and overall survival since the inception of liver grafting, a major consideration in the longterm care of liver transplant patients has become the management of allograft rejection and immunosuppressive therapy. With an increasing number of patients having undergone successful transplantation in the community, practicing gastroenterologists will likely be called upon more frequently to render care to these patients. In this article, the immunobiology of transplantation and rejection is discussed with an emphasis placed on the T-cell-major histocompatibility complex interaction, cytokine stimulation, and adhesion molecule binding. Commonly used immunosuppressive medications and promising ones for the future are reviewed. Also, clinical aspects of the short- and long-term management of immunosuppression are explored.

Graft Rejection↗

PubMed1996

Carcinoid tumor of the common bile duct producing gastrin and serotonin.

Carcinoid tumors of the biliary tract are rare. We report a 47 year-old man who was unexpectedly found to have a nonobstructing carcinoid tumor of the common bile duct during orthotopic liver transplantation for decompensated cirrhosis. No metastases were noted. Five months after resection of the common bile duct and liver transplantation, the patient had no evidence of residual tumor. The carcinoid was a sclerotic tumor of insular type and was immunoreactive for gastrin and serotonin, but nonfunctional. We review the literature on carcinoids of the extrahepatic bile duct.

Adult↗

PubMed1995

Variceal hemorrhage.

Variceal hemorrhage is a complication of portal hypertension that has high mortality and high recurrence rates. Management of variceal bleeding involves three areas: treatment of active hemorrhage, prevention of rebleeding, and prevention of first variceal bleeding. There are two main therapeutic avenues: methods directed at reducing portal pressure, such as pharmacologic therapy, shunt surgery, and TIPS; and methods that act locally by decreasing or interrupting blood flow through a specific varice, such as sclerotherapy, banding, and balloon tamponade. The relative effectiveness of each of these interventions is discussed in this article.

Esophageal and Gastric Varices↗

PubMed1993

A comparison of Streptococcus pyogenes (group A streptococcal) bacteremia at an urban and a suburban hospital. The importance of intravenous drug use.

BACKGROUND: There has been a recent resurgence of severe infections with Streptococcus pyogenes, including bacteremias and a toxic shock-like syndrome. The purpose of this study was to examine the influence of intravenous drug use on the incidence, clinical epidemiology, and severity of S pyogenes bacteremia. METHODS: We conducted a retrospective survey of medical records at a 500-bed tertiary care urban hospital and at a nearby 500-bed suburban university-affiliated hospital. All patients from each hospital with documented S pyogenes bacteremia from January 1, 1979, to December 31, 1989, were included. We examined demographic and clinical data from cases at the two institutions, serologic findings from a subset of isolates from the urban hospital, and factors associated with mortality from S pyogenes bacteremia by stepwise logistic regression analysis. RESULTS: Ninety-five cases of S pyogenes bacteremia were identified, with 65% (62 cases) occurring at the urban center. Intravenous drug use occurred more frequently at the urban center (P < .005); the injecting drug users were significantly younger than the non-drug-using population (P = .001). Infection with the human immunodeficiency virus occurred in a subset of the injecting drug users at the urban center. Cellulitis and cutaneous abscesses were the most common sources of bacteremia at both centers. During the study period, the numbers of S pyogenes bacteremias increased at the urban center (P = .007), accompanied by a significant increase in the proportion of infections associated with parenteral drug use (P = .003). There was no change in the prevalence of any T type throughout the study period and no clustering of T types among injecting drug users. The overall mortality was 23% (20/89). By logistic regression analysis, age older than 65 years (relative risk [RR], 14; 95% confidence interval [CI], 3.2 to 68) and the presence of the toxic shock-like syndrome (RR, 36; 95% CI, 2.2 to 600) were significantly associated with mortality due to S pyogenes bacteremia. CONCLUSIONS: Intravenous drug use accounted for an increase in cases of S pyogenes bacteremia at an inner-city hospital. However, advanced age and the toxic shock-like syndrome were the most important predictors of mortality.

Age Factors↗

PubMed1990

Pneumococcal bacteremia in Charleston County, South Carolina. A decade later.

Since nationwide surveillance for pneumococcal bacteremia in the United States is not done, community-based studies are useful alternative methods to monitor trends in this disease. Data on the incidence of pneumococcal bacteremia in Charleston County, South Carolina, from 1974 to 1976, have been used to support cost-effective pneumococcal vaccine programs for the elderly. We reevaluated the incidence of pneumococcal bacteremia in Charleston County in 1986 and 1987 to assess whether earlier estimates remained valid given changes in medical practice. During 1986 and 1987, overall annual incidence of pneumococcal bacteremia in Charleston County was 18.7 per 100,000 (95% confidence limits, 13.7 to 23.6 per 100,000), which represents a 2.3-fold increase over the earlier rate. The increase coincided with a 2.2-fold increase in the annual number of blood cultures processed at four Charleston County hospital laboratories from 1975 to 1987 despite only a 1.1-fold increase in the number of patients discharged from these hospitals. Annualized rates increased 2.3-fold for adults more than or equal to 65 years old to 53 per 100,000 and 4.6-fold for children less than 2 years old to 162 per 100,000. The case-fatality rate of bacteremic patients was 18%, compared with 21% in the earlier study. The case-fatality rate for adults more than or equal to 65 years of age was 44%. Ninety-one percent of adults 19 to 64 years old with bacteremia had underlying medical conditions for which pneumococcal vaccine is recommended; all persons 55 to 64 years old had at least one underlying condition. The marked increases in pneumococcal bacteremia rates detected are likely due to more routine culturing of blood from symptomatic patients with pneumococcal disease. These findings emphasize the need for effective programs promoting use of pneumococcal vaccine in high-risk groups, particularly those more than or equal to 65 years old, and the development of a more immunogenic vaccine for children less than 2 years old.

Adult↗