Comparison of the cost and effectiveness of two strategies for maintaining hepatitis B immunity in hemodialysis patients

A decision-analysis model was developed to compare the strategies to maintain hepatitis B virus (HBV) immunity in hemodialysis patients who responded to the primary HBV vaccine. Our hypothesis is that the routine, annual administration of the vaccine booster to all hemodialysis patients (non-screening strategy) is more cost-effective than the current strategy of vaccination based on anti-HBs titers (screening strategy). Under baseline assumptions, the screening strategy was less costly and was associated with fewer HBV infections than the non-screening strategy. The results of our model did not support our hypothesis, and indicate that regularly screening patients for HBV immunity before revaccination is less costly and more effective than the empiric vaccination of hemodialysis patients.     

Correlation of renal histopathology with sonographic findings

BACKGROUND: Judgments about irreversible renal disease are frequently based on the sonographic appearance of the kidneys. However, the sensitivity and specificity of sonography in identifying chronic, irreversible disease have never been determined, and the specific pathologic changes that increase renal cortical echogenicity have not been defined. METHODS: We retrospectively compared sonographic parameters (length, quantitative echogenicity, cortical thickness, and parenchymal thickness) to biopsy findings of glomerular sclerosis, tubular atrophy, interstitial fibrosis, and interstitial inflammation in 207 patients. RESULTS: Echogenicity showed the strongest correlation with all 4 histologic parameters (r= 0.28-0.35). Renal size was significantly correlated with glomerular sclerosis (r=-0.26) and tubular atrophy (r= 0.20). Parenchymal thickness, but not cortical thickness, correlated with tubular atrophy (r=-0.23). By multivariate analysis, tubular atrophy and interstitial inflammation, but not interstitial fibrosis, were significant determinants of cortical echogenicity. Severe chronic disease (>50% sclerosed glomeruli or a score of 3 out of 5 or greater for tubular atrophy or interstitial fibrosis) was present in 69% and 47% of patients with combined renal length <20 cm and >20 cm, respectively (P= <0.05). For cortical echogenicity >1.0 (>liver echogenicity) and 1.0. CONCLUSION: Cortical echogenicity is the sonographic parameter that correlates best with renal histopathology. Although size or echogenicity alone are poor predictors of chronic irreversible disease, the likelihood of treatable disease in small kidneys with increased cortical echogenicity is very low.     

Immunization Needs of Chronic Liver Disease Patients Seen in Primary Care Versus Specialist Settings

Chronic liver disease patients may benefit from certain vaccines, but their immunization coverage levels have not been widely studied. We examined the serologic and vaccination status of 693 chronic liver disease patients from 37 primary care and specialist centers. Patients in primary care had more often received influenza (47 versus 32%; P < .001) and pneumococcal (39 versus 19%; P < .001) vaccines. Among patients without documented prior exposure, those seeing specialists had more often completed hepatitis A (28 versus 5%; P < .001) and hepatitis B (29 versus 14%; P < .001) vaccination. Coverage was higher in centers with a policy of vaccinating on-site, among non-Hispanic whites, and among patients with hepatitis C and cirrhosis. In summary, most patients were unprotected against one or more vaccine preventable diseases. The higher coverage rates evident in centers vaccinating on-site suggests a breakdown may occur when patients are referred to alternative vaccination venues.     

Primary prevention of cirrhosis. Public health strategies that can make a difference

Cirrhosis is associated with high morbidity and mortality and often affects persons during the most productive years of life. In the United States, alcoholic liver disease is the leading contributor to the overall prevalence of cirrhosis, followed by infection with hepatitis B virus (HBV) and hepatitis C virus (HCV). In this article, Drs Karsan, Rojter, and Saab examine lifestyle behaviors that can lead to cirrhosis and enumerate public health strategies aimed at primary prevention.     

Macrovesicular hepatic steatosis in living related liver donors: correlation between CT and histologic findings

PURPOSE: To assess degree of macrovesicular steatosis with unenhanced computed tomography (CT) and correlate it with histologic findings in potential donors for living related liver transplantation. MATERIALS AND METHODS: Forty-two candidates underwent unenhanced CT within 4 weeks of core liver biopsy. An experienced liver pathologist, blinded to both CT and surgical findings, retrospectively reviewed biopsy specimens and determined degree of macrovesicular steatosis. A radiologist blinded to histologic grading calculated mean hepatic attenuation in each donor liver by averaging 25 region-of-interest (ROI) measurements on five sections (five ROIs per section). Mean splenic attenuation was calculated with three separate ROI measurements. Liver attenuation index (LAI) was derived and defined as the difference between mean hepatic and mean splenic attenuation. Body mass index (BMI) was determined for each patient. Linear regression analysis was used to correlate degree of macrovesicular steatosis with both LAI and BMI. RESULTS: LAI correctly predicted degree of macrovesicular steatosis in 38 (90%) of 42 cases. In four of four livers, LAI below -10 HU correlated with greater than 30% macrovesicular steatosis (unacceptable for liver transplantation). In nine of 11 livers, LAI was between -10 and 5 HU and correctly predicted 6%-30% steatosis (relative contraindication). In two of 11 cases, LAI overestimated degree of hepatic steatosis. LAI above 5 HU correctly predicted 0%-5% steatosis in 25 of 27 livers. In two of 27 cases, parenchymal hemosiderin deposition led to an increase in LAI into the normal range, despite mild histologically confirmed steatosis. Degree of histologic macrovesicular steatosis correlated well with LAI (r = 0.92) and marginally with BMI (r = 0.45). Of 27 potential donors with normal livers at CT and acceptable LAI levels, four (15%) were deemed poor donor candidates because core biopsy revealed subtle hepatic necrosis and nonspecific hepatitis. CONCLUSION: Although unenhanced CT quantifies the degree of macrovesicular steatosis relatively well, it may preclude a liver biopsy only in a small percentage of potential donors with low LAI (unacceptable degree of steatosis). Core liver biopsy is still necessary in the majority of donors with normal LAI to identify those with both fatty liver and coexistent hemosiderin deposition or radiologically occult diffuse liver diseases.     

Towards evidence based emergency medicine: best BETs from Manchester Royal Infirmary. Antibiotics in patients with isolated chest trauma requiring chest drains

Report by John Butler,
Specialist RegistrarChecked by Ian Sammy, Consultant, and Joel Desmond , Research Fellow     

An economic assessment of pre-vaccination screening for hepatitis A and B

OBJECTIVE: The availability of a single vaccine active against hepatitis A and B may facilitate prevention of both infections, but complicates the question of whether to conduct pre-vaccination screening. The authors examined the cost-effectiveness of pre-vaccination screening for several populations: first-year college students, military recruits, travelers to hepatitis A-endemic areas, patients at sexually transmitted disease clinics, and prison inmates. METHODS: Three prevention protocols were examined: (1) screen and defer vaccination until serology results are known; (2) screen and begin vaccination immediately to avoid a missed vaccination opportunity; and (3) vaccinate without screening. Data describing pre-vaccination immunity, vaccine effectiveness, and prevention costs borne by the health system (i.e., serology, vaccine acquisition, and administration) were derived from published literature and U.S. government websites. Using spreadsheet models, the authors calculated the ratio of prevention costs to the number of vaccine protections conferred. RESULTS: The vaccinate without screening protocol was most cost-effective in nine of 10 analyses conducted under baseline assumptions, and in 69 of 80 sensitivity analyses. In each population considered, vaccinate without screening was less costly than and at least equally as effective as screen and begin vaccination. The screen and defer vaccination protocol would reduce costs in seven populations, but effectiveness would also be lower. CONCLUSIONS: Unless directed at vaccination candidates with the highest probability of immunity, pre-vaccination screening for hepatitis A and B immunity is not cost-effective. Balancing cost reduction with reduced effectiveness, screen and defer may be preferred for older travelers and prison inmates.