Kris Anand

Sevoflurane hepatotoxicity: A case report of sevoflurane hepatic necrosis and review of the literature

Sevoflurane, a halogenated anesthetic, is associated with mild aminotransferase elevations but does not tend to cause clinically significant hepatotoxicity. We report a rare case of severe hepatic necrosis following exposure to sevoflurane during surgery. A 37-year-old man presented with nausea,vomiting, abdominal pain, and jaundice on the third postoperative day after an abdominal wall mass resection. Laboratory tests showed markedly elevated aminotransferase levels, hyperbilirubinemia, and coagulopathy. His viral hepatitis and human immunodeficiency virus (HIV) serologies were negative for acute infection, and his Epstein-Barr virus (EBV) and cytomegalovirus (CMV) serologies were suggestive of recent EBV infection and remote CMV infection. Antinuclear antibody and anti-smooth muscle antibody screens were negative. Ceruloplasmin and serum copper values were in the normal range. The histopathological findings included an acute centrilobular cholestatic hepatocellular injury compatible with the clinical history of acute drug-induced hepatotoxicity. The patient improved with conservative management. Unlike other halogenated anesthetics, proposed mechanisms of sevoflurane hepatotoxicity include production of compound A, increased cytosolic free Ca(2+), and activation of free radical metabolizing enzymes. The patient was likely susceptible to toxicity due to an underlying EBV infection and a probable history of exposure to halogenated anesthetics. Sevoflurane is generally considered to be relatively safe for subjects with mild liver dysfunction, in comparison with other halogenated anesthetics. However, this case suggests that sevoflurane can lead to severe life-threatening hepatic necrosis in at-risk individuals.

Colorectal cancer screening in elderly African-American patients

The study by Smoot DT et al. [1] is an interesting study highlighting the outcome of colonoscopy in elderly African-American patients. The study included 922 elderly patients who underwent colonoscopy; the predominance of females in the study, i.e. 67.7% female vs. 32.4% male, is not discussed. Females are known to have lower incidence of colorectal cancer (CRC) [2] irrespective of race, but the study has shown a higher incidence of CRC 29/623 (4.6%) as compared to males 13/299 (4.4%). Further, the patients are classified into average and high risk groups based on indication of colonoscopy. In the high risk group, inclusion of the subjects with a personal history of CRC is likely to affect the results as the recurrence rates of colon cancer are high and variable depending on the stage and treatment of colon cancer. The United States Preventive Services Task Force (USPSTF) recommends against routine screening for CRC in adults 76–85 years of age [3]. The considerations that support CRC screening in an individual patient are not clear. Thus, decision to recommend CRC in this subgroup depends on multiple factors. The study has highlighted certain factors such as blood in stools to have a high predictive value for CRC. There are multiple other factors which have a potential impact on colonoscopy outcomes in elderly. The results of previous colonoscopies definitely affect rescreening decisions [4], but the interval from previous colonoscopy should be considered when making the decision to repeat the examination. Similarly, advance age and co-morbidities have shown to adversely affect bowel preparation. The study by Smoot et al. [1] fails to provide information about the previous colonoscopy results/interval/bowel preparation/completion rates. It has been reported that risk of adverse events increases with age and with specific co-morbid conditions [5]; thus, this factor needs to be taken into account when making a decision. Another approach can be screening of selected individuals with non-invasive tests, such as the immunochemical occult-blood test, which has a fair sensitivity of 60–85% for colon cancer, followed by colonoscopy wherever indicated. As in countries like the United Kingdom, Italy and Norway offering flexible sigmoidoscopy as a screening tool can be considered in this subgroup [6]. The benefits of detecting CRC early is the mainstay of our efforts to offer screening. The outcome of CRC depends on the stage of diagnosis. Co-existing chronic illness is associated with a substantial reduction in life expectancy after diagnosis of early-stage CRC, and also affects the tolerance to various therapies [7]. Thus, elderly patients with multiple co-morbidities and limited life expectancy are unlikely to be treatment candidates and thus have questionable benefit from screening colonoscopy. The information about the co-morbidities and stage of CRC is not included in this study; hence, it is difficult to comment on the impact of diagnosing cancers in the study. S. Singhal (&) Gastroenterology, Department of Internal Medicine, Chicago Medical School at Rosalind Franklin University, North Chicago, IL, USA e-mail: sdsinghal@gmail.com

Sa1119 Will Split Dosing of Bowel Preparation Improve Quality of Colonoscopy and Increase Colorectal Neoplasm Detection

BackgroundAdequate bowel preparation is an important element in screening colonoscopy. Bowel preparation with ingestion of polyethylene glycol(PEG)solution the evening before colonoscopy results in suboptimal cleansing and affects the diagnostic yield. The American College of Gastroenterology supports the concept of split dosing to enhance the efficacy of bowel preparation. AimsTo compare the efficacy of the bowel preparation with split dosing(SD)of polyethylene glycol(PEG)solution versus the conventional dosing(CD). MethodsCharts of 492 consecutive patients undergoing screening colonoscopy by a single endoscopist from January 2010 to October 2011 were reviewed. Of these, 243 patients had received SD bowel preparation(SD group)compared to 249 patients who had received CD bowel preparation(CD group).Data on patient demographics, quality of preparation,cecal intubation rate, polyp detection rate, adenoma detection rate and polyp histology were collected. Significant Colorectal Neoplasm(CRN)was defined as polyp > 1 cm in size,≥ 3 adenomas and those with villous histology. Right sided colon was defined as cecum, ascending colon, transverse colon. Left sided colon was defined as descending colon, sigmoid colon and the rectum. A weighted score was assigned to poor, sub-optimal and good quality of bowel preparation as determined by the endoscopist. Results: Table 1 lists the patient demographics in the two groups. Both groups were well-matched in terms of age, sex and ethnicity. Polyp detection rate was 40% in SD group vs.33% in CD group (p=0.09). There was no significant difference in adenoma detection rate (24% vs. 23%, p=0.87) and cecal intubation rate (98% vs. 97%, p=0.35) between two groups. Significant CRN detection rate on right side was 12% with SD group and 4% with CD group(p=0.028). On left side significant CRN detection rate was 7% with SD group and 6% with CD group. 2 colorectal cancers were detected in the SD group and none in CD group(Table 2). Bowel preparation score was 2.8 in SD group compared to 2.6 in CD group Conclusions: Both the groups had similar bowel preparation scores and cecal intubation rates. However, bowel preparation with split-dose PEG solution resulted in a trend towards a higher polyp detection rate though it did not meet statistical significance. The SD regimen was efficient in detecting more significant CRN on the right side compared to CD regimen. Table 1