Diagnosis of hepatitis C

Currently, the second- and third-generation enzyme immunoassays (EIA-2 and EIA-3) for hepatitis C virus antibody (anti-HCV) are the most practical screening tests for the diagnosis of HCV infection. The need for and the choice of supplementary or confirmatory tests depend on the clinical setting and the likelihood of a true-positive EIA result. Detection of HCV RNA in serum by polymerase chain reaction (PCR) assay is the gold standard for the diagnosis of HCV infection. However, the lack of uniformity in current PCR assays has tarnished this standard. Confirmatory tests for the diagnosis of HCV infection are in general unnecessary in anti-HCV-positive patients who present with chronic liver disease. When indicated, the most appropriate test in this setting is a qualitative PCR assay for HCV RNA. Confirmatory tests should always be performed in anti-HCV-positive blood donors and individuals with normal aminotransferase levels. The most appropriate approach is to retest for anti-HCV using recombinant immunoblot assay (RIBA) and then test for HCV RNA using PCR assay in those who are RIBA positive or indeterminate. Liver histology is the gold standard in assessing severity of liver disease. Quantitative tests for serum HCV RNA levels do not help to determine the severity of liver disease. At the moment, HCV genotyping should be considered a research tool and not a part of the diagnostic work-up in clinical practice. The goals of treatment for chronic hepatitis C are sustained biochemical and virological response. Viral clearance should be determined by qualitative PCR assay. Quantifying serum HCV RNA level can help in predicting response to interferon treatment, but further studies using more standardized assays are needed to determine if these values can be used to select patients for treatment.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34770/1/510260709_ftp.pd

Unsuspected infection is infrequent in asymptomatic outpatients with refractory ascites undergoing therapeutic paracentesis

Large-volume paracentesis is a safe and effective means of treating patients with refractory ascites. However, there is limited information regarding the need for ascitic fluid studies in asymptomatic outpatients presenting for therapeutic paracentesis. The aim of this prospective study was to define the incidence and natural history of peritoneal fluid infection in asymptomatic outpatients undergoing therapeutic paracentesis. Methods : Over a 13-month period, 118 therapeutic paracenteses were performed in 29 outpatients with decompensated cirrhosis (Child-Pugh class B = 38%, C = 62%). After a brief medical history and physical examination, ascitic fluid cell count with differential and culture were obtained from all participating subjects. Seven (24%) of the subjects were receiving norfloxacin prophylaxis, accounting for antibiotic coverage during 40% of the procedures performed. The clinical course and outcome of study subjects during a mean follow-up of 137 days was reviewed. Results : All 118 (100%) of the ascitic fluid samples demonstrated absolute neutrophil counts of <250/mm 3 (mean = 6.5 ± 22.5 pmn/mm 3 ). Asymptomatic bacterascites was identified from three of the 118 (2.5%) fluid samples, but all of these subjects spontaneously recovered without treatment or sequelae. During follow-up, six episodes of symptomatic or hospital-associated peritoneal fluid infection were identified in study participants, emphasizing the importance of fluid studies in other clinical settings. Conclusion : Although further studies are needed, the routine culture of ascitic fluid in asymptomatic outpatients with refractory ascites requiring therapeutic paracentesis may not be necessary when there is a low index of suspicion for occult infection. In circumstances of clinical uncertainty, however, obtaining ascitic fluid cell counts with differential is recommended to insure patient safety.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73079/1/j.1572-0241.1999.01445.x.pd

A randomized, controlled trial to assess a novel colorectal cancer screening strategy: the conversion strategy

Our study was a randomized, controlled trial to assess a novel strategy that provides comprehensive colorectal cancer screening in a single visit versus traditional sigmoidoscopy and, where appropriate, colonoscopy on a subsequent day. METHODS : Consecutive patients referred for screening were randomized to control or so-called “conversion” groups. Patients in the control group were prepared for sigmoidoscopy with oral phospho-soda. Those with an abnormal sigmoidoscopy were scheduled for colonoscopy on a future day after oral polyethylene glycol preparation. In the conversion group, patients were prepared with oral phospho-soda. Patients with a polyp >5 mm or multiple diminutive polyps were converted from sigmoidoscopy to colonoscopy, allowing comprehensive screening in a single visit. Clinical outcomes were assessed by postprocedure physician and patient questionnaires. RESULTS : Two hundred thirty-five patients were randomized (control = 121, conversion = 114). In the control group, 28% had an indication for colonoscopy. Three of 33 (9%) with an abnormal sigmoidoscopy did not return for colonoscopy. At colonoscopy, 27% had a proximal adenoma. In the conversion group, 28% had an abnormal sigmoidoscopy and underwent conversion to colonoscopy. Forty-one percent undergoing colonoscopy in the conversion group had a proximal adenoma. Physicians reported no differences in preparation or procedure difficulty, whereas patients reported no differences in the level of comfort or overall satisfaction between groups. When queried regarding preferences for future screening, 96% chose the conversion strategy. CONCLUSIONS : The conversion strategy led to similar outcomes compared to traditional screening while improving compliance with colonoscopy in patients with an abnormal sigmoidoscopy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73097/1/j.1572-0241.2000.02231.x.pd