Neutrophils - Biology and Diversity

Neutrophils, the most abundant white blood cells in the human circulation, play crucial roles in various diseases, including kidney disease. Traditionally viewed as short-lived pro-inflammatory phagocytes that release reactive oxygen species, cytokines and neutrophil extracellular traps, recent studies have revealed their complexity and heterogeneity, thereby challenging this perception. Neutrophils are now recognized as transcriptionally active cells capable of proliferation and reverse migration, displaying phenotypic and functional heterogeneity. They respond to a wide range of signals and deploy various cargo to influence the activity of other cells in the circulation and in tissues. They can regulate the behavior of multiple immune cell types, exhibit innate immune memory, and contribute to both acute and chronic inflammatory responses while also promoting inflammation resolution in a context-dependent manner. Here, we explore the origin and heterogeneity of neutrophils, their functional diversity, and the cues that regulate their effector functions. We also examine their emerging role in infectious and non-infectious diseases with a particular emphasis on kidney disease. Understanding the complex behavior of neutrophils during tissue injury and inflammation may provide novel insights, thereby paving the way for potential therapeutic strategies to manage acute and chronic conditions. By deciphering their multifaceted role, targeted interventions can be developed to address the intricacies of neutrophil-mediated immune responses and improve disease outcomes.

Exosomes from Von Hippel-Lindau-Null Cancer Cells Promote Metastasis in Renal Cell Carcinoma

Exosomes are extracellular vesicles that modulate essential physiological and pathological signals. Communication between cancer cells that express the von Hippel-Lindau (VHL) tumor suppressor gene and those that do not is instrumental to distant metastasis in renal cell carcinoma (RCC). In a novel metastasis model, VHL(-) cancer cells are the metastatic driver, while VHL(+) cells receive metastatic signals from VHL(-) cells and undergo aggressive transformation. This study investigates whether exosomes could be mediating metastatic crosstalk. Exosomes isolated from paired VHL(+) and VHL(-) cancer cell lines were assessed for physical, biochemical, and biological characteristics. Compared to the VHL(+) cells, VHL(-) cells produce significantly more exosomes that augment epithelial-to-mesenchymal transition (EMT) and migration of VHL(+) cells. Using a Cre-loxP exosome reporter system, the fluorescent color conversion and migration were correlated with dose-dependent delivery of VHL(-) exosomes. VHL(-) exosomes even induced a complete cascade of distant metastasis when added to VHL(+) tumor xenografts in a duck chorioallantoic membrane (dCAM) model, while VHL(+) exosomes did not. Therefore, this study supports that exosomes from VHL(-) cells could mediate critical cell-to-cell crosstalk to promote metastasis in RCC.

POS0950 LONG-TERM FOLLOW-UP OF STARTING AND SWITCHING FROM ORIGINAL ADALIMUMAB TO ADALIMUMAB BIOSIMILAR: REAL-WORLD DATA IN AXIAL SPONDYLOARTHRITIS

Background

Biological drugs have revolutionized the treatment of rheumatic diseases, and the recent expiry of the patents for many biological agents has led to the marketing of highly similar, low-cost versions known as biosimilars. However, questions regarding its efficacy compared to bio-originator drugs, in a real-life setting, have been raised. National Institute for Health and Care Excellence (NICE) guidelines state that the response to biologic disease-modifying anti-rheumatic drugs (bDMARDs) should be assessed 12 weeks after the beginning of the drug. Treatment should only be continued if there is clear evidence of response, defined as a reduction in the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score to 50% of the pre-treatment value or by 2 or more units and a reduction in the 10-cm spinal pain visual analogue scale (VAS) by 2 cm or more.

Objectives

To compare the response to adalimumab (ADA) originator and biosimilar in bDMARD-naïve patients with axial spondyloarthritis (axSpA) and in patients who switched from originator to biosimilar drug, accordingly to NICE guidelines; to compare the effectiveness and safety of the originator and biosimilar drugs in patients with axSpA, measured by persistence rates (PR) over three years.

Methods

A retrospective observational single-centre UK study was performed in bDMARD-naïve patients with a clinical diagnosis of axSpA who initiated treatment with ADA (original or biosimilar) and in patients who switched from originator to biosimilar drug. Descriptive statistics were used. Disease activity at baseline and follow-up data at 3 and 6 months of treatment was compared using the chi-square test. The Kaplan-Meier method was used to calculate persistence rates in biologic treatment over time. Reasons for discontinuing therapy were summarized using descriptive statistics and stratified by treatment.

Results

A total of 153 patients were included: 83 patients started on original ADA, 31 started on biosimilar ADA and 40 switched from original to biosimilar drug. The population’s baseline characteristics are similar in the three groups. However, some differences were found, namely disease duration was longer in the group that did switch and the disease activity is similar in patients who started original and biosimilar ADA and was lower in the group of patients who switched from original to the biosimilar. The 3-year PR was not significantly different between originator and biosimilar ADA in bDMARD naïve patients and in the group of patients that switched from original drug to biosimilar drug (p=0.080), as shown in Figure 1. In the original ADA group, 3-years PR was 67.5% with a median time-on-drug (TOD) of 29.5 months; for biosimilar drug, 3-years PR was 64.5%, with a median TOD of 24.2 months. In patients who switched from original to biosimilar drug, 3-years PR was 77.5% with a median TOD of 30.3 months. Response to treatment according to NICE guidelines was similar between original and biosimilar drugs (p>0.05). Overall, 47 (30.7%) patients stopped adalimumab (27 patients on original drug and 20 on biosimilar drug). Discontinuations due to adverse events and inefficacy were the most frequent, and there were no significant differences between original and biosimilar drugs. Other reasons for discontinuation were less frequent, such as patient choice, loss of follow-up and death, and again without differences between original and biosimilar drugs.

Figure 1.

Drug survival in the three adalimumab groups (original adalimumab – blue line, biosimilar adalimumab – red line, and switch from original to biosimilar adalimumab – green line)

Conclusion

Adalimumab original and biosimilar used as a first-line biological treatment showed similar effectiveness and safety in our long-term cohort of patients with axSpA. Switch from original to biosimilar drug showed to have a good persistence on drug after three years of follow-up (77.5%).

Disclosure of Interests

Ana Sofia Pinto: None declared, Kalveer Flora: None declared, Dilpreet Matharu: None declared, Anthony Isaacs: None declared, Pedro Machado Speakers bureau: Received consulting/speaker’s fees from Abbvie, BMS, Celgene, Eli Lilly, Galapagos, Janssen, MSD, Novartis, Orphazyme, Pfizer, Roche and UCB, all unrelated to this manuscript, Consultant of: Received consulting/speaker’s fees from Abbvie, BMS, Celgene, Eli Lilly, Galapagos, Janssen, MSD, Novartis, Orphazyme, Pfizer, Roche and UCB, all unrelated to this manuscript

Coping strategies towards mobbing used by medical and nursing staff in the hospitals of the prefecture of Etoloakarnania, Greece

Introduction

The aim of this study is to investigate mobbing in the Hospitals of Etoloakarnania, Greece. Additionally, this research aims to find out which coping strategies are used by health care professionals who have suffered mobbing and how their quality of life has been affected.

Objectives

This research aims to depict mobbing phenomenon’s extent and investigate the coping strategies and quality of life of working staff, victims of mobbing.

Methods

The research methodology was based on two questionnaires: LIPT scale and the scale of assessing bullying management strategies, as well as demographic data, which were answered by 130 people. A sufficient sample for the needs of this study to produce comparable results with the existing literature.

Results

Mobbing is observed to a large extent of 83.8% , which, however, seems to be at lower levels in relation to corresponding researches abroad. In addition, the majority of respondents who appear to have been harassed at work are mostly women (78.5%), which seems to be in line with global studies. Τhe consultants and the supervisors take advantage of their position of power and impose or change duties on other staff (45.3%), in order to punish their subordinates, exacerbating the phenomenon of mobbing, also. Finally, the participants recognize the phenomenon and look for the majority of positive ways of action (65%), while they do not resort to non-constructive ways of solving the problem.

Conclusions

Mobbing is a serious phenomenon that affects working staff’s mental health and quality of life. Policies should address effectively this deleterious aggressive behaviour.

Disclosure

No significant relationships.

141 New Guidelines to Reduce Unnecessary Blood Tests, Delayed Discharge and Costs Following Robot Assisted Radical Prostatectomy

Objectives

Routine postoperative blood tests (POBT) following robot assisted radical prostatectomy (RARP) are used to evaluate the impact of surgery on pre-existing co-morbidities and to detect early complications. This practice dates back to an era of open surgery, when blood loss and complication rates were higher. We propose new guidelines to improve the specificity of POBT.

Method

The cases of 1040 consecutive patients who underwent a primary or salvage RARP at two large tertiary urology centres in the United Kingdom were retrospectively reviewed to form new guidelines. The new guidelines were prospectively validated in a sample of 300 patients.

Results

Derivation Dataset: 3% and 5% had intra- and post-operative Clavien-Dindo complications, respectively. 15% had clinical concerns postoperatively. 0.9% required perioperative transfusion. 78% had routine blood tests without clinical concerns, none of whom developed a complication. 98% of complications were suspected by clinical judgement. 6% of patients had a discharge delay of ≥ 1 day due to delayed or incomplete blood tests. Validation Dataset: No significant difference existed in complication, clinical concern or transfusion rates between the derivation and validation datasets. Number of POBT requested reduced by 73% (p < 0.001). The new guidelines improved POBT sensitivity for complications from 98% to 100% and specificity from 0% to 74%. Discharge delays reduced from 6% to 0% (p = 0.008). Cost savings were £178 per patient.

Conclusions

Postoperative complications and transfusion following RARP are rare. Routine POBT without clinical indication are unnecessary and inefficient. A guideline-based approach to POBT can reduce costs and optimise discharge without compromising patient safety or care.

283 Salvage Versus Primary Robot-Assisted Radical Prostatectomy: A Propensity-Matched Comparative Effectiveness Study from A High-Volume Tertiary Centre

Aim

Salvage Robot-Assisted Radical Prostatectomy (sRARP) is a potential treatment option for locally recurrent Prostate Cancer after non-surgical primary treatment. There are minimal data comparing outcomes between propensity-matched salvage and primary Robot-Assisted Radical Prostatectomy (RARP). We compare perioperative, oncological, and functional outcomes of sRARP with primary RARP and between sRARP post-whole and focal gland therapy.

Method

1:1 propensity-matched comparison of 146 sRARP with primary RARP from a cohort of 3,852 consecutive patients from a high-volume tertiary centre.

Results

There were no significant differences in patient characteristics between the salvage and primary RARP groups. Grade III-V Clavien-Dindo complication rates were 1.3% and 0% in the salvage and primary groups, respectively (p = 0.310). Median (IQR) follow-up was 16 (10,30) and 21 (13,33) months in the salvage and primary groups, respectively. BCR rates were 30.8% and 13.7% in the salvage and primary groups, respectively (p < 0.001). Pad-free continence rates were 79.1% and 85.4% at two years in the salvage and primary groups, respectively (p = 0.160). ED rates were 95.2% and 77.4% in the salvage and primary groups, respectively (p < 0.001). Comparing the whole gland and focal gland groups, BCR rates were 33.3% and 29.1%, respectively (p = 0.687), pad-free continence rates were 66% and 89.3%, respectively (p = 0.001), and ED rates were 98.3% and 93%, respectively (p = 0.145).

Conclusions

SRARP has similar perioperative but inferior oncological outcomes to primary RARP. Continence rates are similar to primary RARP, but potency is worse. Perioperative and oncological outcomes of sRARP after focal gland therapy are similar but continence outcomes are superior compared to sRARP after whole gland therapy.

O50 New guidelines to reduce unnecessary blood tests, delayed discharge and costs following robot assisted radical prostatectomy

Introduction

Routine postoperative blood tests (POBT) are used to evaluate the impact of surgery on pre-existing co-morbidities and to detect early complications. This practice dates back to an era of open surgery, when blood loss and complication rates were higher. We propose new guidelines to improve the specificity of POBT.

Method

The cases of 1040 consecutive patients who underwent a primary or salvage RARP at two large tertiary urology centres in the United Kingdom were retrospectively reviewed, and new guidelines were designed. The guidelines were prospectively validated in a cohort of 300 patients.

Result

Derivation Dataset 3% and 5% had intra- and post-operative Clavien-Dindo complications, respectively. 15% had clinical concerns postoperatively. 0.9% required perioperative transfusion. 78% had routine blood tests without clinical concerns, none of whom developed a complication. 98% of complications were suspected by clinical judgement. 6% of patients had a discharge delay of ≥ 1 days due to delayed or incomplete blood tests.

Validation Dataset No significant difference existed in complication, clinical concern or transfusion rates between the derivation and validation datasets. New guidelines improved sensitivity for complications from 98% to 100% and specificity from 0% to 74%. The number of blood tests requested reduced by 73% (P < 0.001). Discharge delays reduced from 6% to 0% (P = 0.008). Cost savings were £178 per patient.

Conclusion

Postoperative complications and transfusion following RARP are rare. Routine POBT without clinical indication are unnecessary and inefficient. A guideline-based approach to POBT can reduce costs and optimise discharge without compromising patient safety or care.

Take-home Message

Routine postoperative blood tests following robot assisted radical prostatectomy are often unnecessary. A guideline-based approach can reduce costs and optimise patient care.

236 Novel Guidelines to Avoid Routine Blood Tests After Robotic Assisted Radical Prostatectomy (RARP)

Introduction

Patients undergoing RARP commonly require routine post-operative blood tests. This practice dates from an era of open surgery, with increased blood loss and complications. We aim to improve specificity of blood test requests with novel guidelines.

Method

1039 consecutive RARP patients at two tertiary urology centres in the UK were audited. Novel guidelines constructed based on risk stratified evidence from the initial audit were used to prospectively audit 133 patients.

Results

16% had clinical concerns post-operatively. 1% and 4% had an intra- and post-operative complication. Intra- or post-operative clinical judgement flagged post-operative complications in 99.9%. 80% had routine blood tests with no clinical concerns. 6% had delayed discharge due to delayed processing of blood tests. 0.9% received a peri-operative transfusion.

Re-Audit Novel guidelines reduced the number of blood tests requested from 100% to 36%. Specificity in diagnosing a complication improved from 0% to 67%. Discharge delays reduced from 6% to 0% and no post-operative complications were missed (sensitivity 100%).

Conclusions

Routine blood tests, without an indication, did not flag any additional post-operative complications. Blood transfusion is rare for RARP. Novel guidelines to request post-operative blood tests will reduce costs and discharge delays whilst maintaining appropriate patient safety and care.

Pertussis outbreak in an elementary school with high vaccination coverage

BACKGROUND

An outbreak of pertussis in a US elementary school with high vaccination coverage was investigated to evaluate vaccine effectiveness and to identify potential contributing factors.

METHODS

Survey and cohort study of all 215 students of an elementary school (including 36 case patients) and 16 secondary cases among contacts.

RESULTS

Fifty-two pertussis cases were identified (attack rate among students, 17%). Receipt of <3 doses of pertussis-containing-vaccine compared with receipt of complete vaccination series was a significant risk factor for pertussis [relative risk, 5.1; 95% confidence interval (CI), 3 to 8.6]. The effectiveness of the complete vaccination series was 80% (95% CI 66 to 88). No evidence of waning immunity among students was found. The following contributing factors for the outbreak were identified: multiple introductions of pertussis from the community; delays in identification and treatment of early cases; and high contact rates among students. Antimicrobial treatment initiated >14 days after cough onset was associated with increased risk of further transmission of pertussis (relative risk, 10.1; 95% CI 1.5 to 70.3) compared with treatment within 14 days of onset.

CONCLUSIONS

This investigation demonstrated the potential for pertussis outbreaks to occur in well-vaccinated elementary school populations. Aggressive efforts to identify cases and contacts and timely antimicrobial treatment can limit spread of pertussis in similar settings. High vaccination coverage should be maintained, because vaccination significantly reduces the risk of the disease throughout the elementary school years, and to ensure timely diagnosis and treatment health care providers should maintain a high index of suspicion for pertussis among elementary school age children.

Gastroesophageal reflux disease. Control of symptoms, prevention of complications

GERD is a common disease that has a significant impact on patients' quality of life. Many surveys have shown that up to 60% of the population suffers from GERD at some time. Heartburn and acid regurgitation are the classic symptoms, but manifestations are variable. Of the several extraesophageal manifestations of GERD, reflux-induced asthma may be the most important. Complications of GERD include peptic strictures of the esophagus and Barrett's metaplasia. Clinical diagnosis of GERD can be confirmed by response to antisecretory therapy. A high-dose trial of a PPI is becoming an accepted diagnostic technique for uncomplicated mild or moderate GERD. Endoscopic examination and ambulatory esophageal pH monitoring still have a role in the evaluation of severe GERD or when other diseases are suspected. Lifestyle changes rarely are beneficial, and antisecretory therapy remains the mainstay of GERD treatment. PPIs have been shown to be more effective than H2 blockers. Antireflux surgery is indicated in some patients. Healing of esophagitis can take up to 8 weeks; failure to control symptoms necessitates the use of higher drug doses. Failure to control symptoms with high-dose PPI treatment raises the likelihood of other causes.

EUS in cirrhotic patients with and without prior variceal hemorrhage in comparison with noncirrhotic control subjects

BACKGROUND

Endoscopic ultrasound (EUS) was used to evaluate cirrhotic patients with and without prior variceal hemorrhage. The findings were compared with those of EUS in noncirrhotic control subjects to determine EUS features indicative of cirrhosis and of a risk for variceal hemorrhage.

METHODS

Patients with cirrhosis undergoing indicated endoscopic screening for varices or surveillance after endoscopic therapy for variceal hemorrhage were studied and compared with healthy noncirrhotic control patients undergoing EUS for benign conditions.

RESULTS

Sixty-six cirrhotic patients (31 with prior hemorrhage) and 32 control patients were studied. Nonhemorrhage cirrhotic patients had more severe liver disease by Child's class (p = 0.02) and less beta-adrenergic blocker usage (p < 0.0001). Paraesophageal varices were detected in 97% of cirrhotic patients and 3% of control patients (p < 0.001) and were a more sensitive predictor of cirrhosis than varices at endoscopy (74%, p < 0.0001). Azygos vein and thoracic duct diameters, and gastric mucosa and submucosa thickness were greater for cirrhotic than control patients (p < 0.001). More hemorrhage patients had large (5 mm or greater) paraesophageal varices (odds ratio 3.1: 95% CI [1.1, 8.3]; p < 0.05) and paragastric varices (odds ratio 3.7: 95% CI [1.3, 10.2]; p = 0.01). Paraesophageal varix size correlated with ascites (p = 0.03) and, for nonhemorrhage patients, with Child's class (p < 0.01).

CONCLUSIONS

Paraesophageal and paragastric varices correlate with the presence and severity of liver disease and portal hypertension. These data support the hypothesis that large paraesophageal and paragastric varices (5 mm or greater) may be risk factors for variceal hemorrhage, an observation that merits further prospective study. Cirrhosis causes dilation of the azygos vein and thoracic duct and thickening of gastric mucosa and submucosa.

Factors predicting the presence of esophageal or gastric varices in patients with advanced liver disease

OBJECTIVE

Recently it has been recommended that all cirrhotic patients without previous variceal hemorrhage undergo endoscopic screening to detect varices and that those with large varices should be treated with beta-blockers (American College of Gastroenterology guidelines). However, endoscopic screening only of patients at highest risk for varices may be the most cost effective.

METHODS

Ninety-eight patients without a history of variceal hemorrhage underwent esophagogastroduodenoscopy as part of a liver transplant evaluation. Univariate/multivariate analysis was used to evaluate associations between the presence of varices and patient characteristics including etiology of liver disease, Child-Pugh class, physical findings (spider angiomata, splenomegaly, and ascites), encephalopathy, laboratory parameters (prothrombin time, albumin, bilirubin, BUN, creatinine, and platelets), and abdominal ultrasound findings (portal vein diameter/flow, splenomegaly, and ascites).

RESULTS

The causes of cirrhosis among the 67 men and 31 women (mean age, 48 yr) included 28% Hepatitis C/alcoholism, 25% Hepatitis C, 13% alcoholism, 9% primary sclerosing cholangitis/primary biliary cirrhosis, 9% cryptogenic, 6% Hepatitis B, 1% Hepatitis B and C, and 9% other. Patients were Child-Pugh class A 34%, B 51%, and C 15%. Endoscopic findings included esophageal varices in 68% of patients (30% were large), gastric varices in 15%, and portal hypertensive gastropathy in 58%. Platelet count <88,000 was the only parameter identified by univariate/multivariate analysis (p < 0.05) as associated with the presence of large esophageal varices (odds ratio 5.5; 95% confidence interval 1.8-20.6) or gastric varices (odds ratio 5; 95% confidence interval 1.4-23).

CONCLUSIONS

Platelet count <88,000 is associated with the presence of esophagogastric varices. A large prospective study is needed to verify and validate these findings and may allow identification of a group of patients who would most benefit from endoscopic screening for varices.

Comparison of formats for the development of fiber-optic biosensors utilizing sol-gel derived materials entrapping fluorescently-labelled protein

The development of fiber-optic biosensors requires that a biorecognition element and a fluorescent reporter group be immobilized at or near the surface of an optical element such as a planar waveguide or optical fiber. In this study, we examined a model biorecognition element-reporter group couple consisting of human serum albumin that was site-selectively labelled at Cys 34 with iodoacetoxy-nitrobenzoxadiazole (HSA-NBD). The labelled protein was encapsulated into sol-gel derived materials that were prepared either as monoliths, as beads that were formed at the distal tip of a fused silica optical fiber, or as thin films that were dipcast along the length of a glass slide or optical fiber. For fiber-based studies, the entrapped protein was excited using a helium-cadmium laser that was launched into a single optical fiber, and emission was separated from the incident radiation using a perforated mirror beam-splitter, and detected using a monochromator-photomultiplier tube assembly. Changes in fluorescence intensity were generated by denaturant-induced conformational changes in the protein or by iodide quenching. The analytical parameters of merit for the different encapsulation formats, including minimum protein loading level, response time and limit-of-detection, were examined, as were factors such as protein accessibility, leaching and photobleaching. Overall, the results indicated that both beads and films were suitable for biosensor development. In both formats, a substantial fraction of the entrapped protein remained accessible, and the entrapped protein retained a large degree of conformational flexibility. Thin films showed the most rapid response times, and provided good detection limits for a model analyte. However, the entrapment of proteins into beads at the distal tip of fibers provided better signal-to-noise and signal-to-background ratios, and required less protein for preparation. Hence, beads appear to be the most viable method for interfacing of proteins to optical fibers.

Musculoskeletal pain and fatigue are associated with chronic hepatitis C: a report of 239 hepatology clinic patients

OBJECTIVE

The aim of this study was to identify the frequency of fatigue and musculoskeletal pain in hepatitis C compared with other liver diseases.

METHODS

Hepatology outpatients were evaluated by questionnaire for musculoskeletal pain and fatigue. Charts were reviewed for diagnoses, aminotransferases, histology, treatment, and presence of hepatitis C by second generation ELISA and/or polymerase chain reaction. The frequency of symptoms in patients with and without hepatitis C were compared.

RESULTS

In 239 patients (mean age 46.7 +/- 11.6 yr; 52% male) musculoskeletal pain was present in 70% for 6.7 +/- 8.3 yr and fatigue in 56% for 3.3 +/- 5.1 yr. Backache was the most common complaint (54%), followed by morning stiffness (45%), arthralgia (42%), myalgia (38%), neck pain (33%), pain "all over" (21%), and subjective joint swelling (20%). Diffuse body pain was present in 23% on a pain diagram and was strongly associated with fatigue. There was a significant association between hepatitis C positivity and the presence of musculoskeletal pain (81% of HCV-positive compared with 56% of HCV-negative patients, respectively; p = 0.0001), and fatigue (67% compared with 44%; p = 0.001). Musculoskeletal pain was more frequent among patients with isolated hepatitis C infection than among patients with isolated hepatitis B or alcoholic liver disease (91%, 59%, and 48%, respectively; p = 0.004). Similarly, fatigue was more frequent among patients with isolated hepatitis C than among those with isolated alcoholic liver disease or hepatitis B (66%, 30%, and 29%, respectively; p = 0.004). There was no relationship between musculoskeletal complaints and possible route of acquiring hepatitis C, levels of aminotransferases, liver disease severity on biopsy, or interferon treatment.

CONCLUSIONS

Musculoskeletal pain and fatigue are frequent in hepatology clinic attendees, particularly those with hepatitis C and are unrelated to severity of liver disease, route of infection, or interferon therapy.

Prevalence of upper and lower gastrointestinal tract findings in liver transplant candidates undergoing screening endoscopic evaluation

OBJECTIVE

The incidence of esophageal and gastric varices and portal hypertensive gastropathy (PHG) has been well studied in cirrhotic patients. Because little is known of the prevalence of other upper and lower gastrointestinal tract pathology in pre-liver transplant candidates, we retrospectively studied the prevalence of and factors associated with these findings.

METHODS

One hundred and twenty pre-liver transplant candidates underwent esophagogastroduodenoscopy to evaluate for varices, and 71 of them also underwent flexible sigmoidoscopy to screen for colorectal carcinoma. The association of upper and lower GI tract pathology with Child-Pugh Class, etiology of cirrhosis, and signs of portal hypertension, including presence and size of esophageal varices, presence of gastric varices, PHG, ascites, and splenomegaly, was analyzed using univariate and multivariate analysis.

RESULTS

Etiology of cirrhosis among 87 men and 33 women (mean age, 52 yr) included 25% hepatitis C, 27% hepatitis C/alcohol, 15% alcohol, 10% primary sclerosing cholangitis/primary biliary cirrhosis, 9% cryptogenic, 8% metabolic, and 6% hepatitis B. Prevalence of Child-Pugh Classes A, B, and C were 34%, 49%, and 17%, respectively; 73% of patients had esophageal varices (23% were large), 62% PHG (23% were severe), and 16% gastric varices. Excluding varices and PHG, endoscopic findings in the upper GI tract (n = 120) included: 13% esophagitis/ulcers, 7.5% gastritis, 8% duodenitis, 2% Barrett's esophagus, 3% duodenal ulcers, and 2% gastric ulcers. Findings in the lower gastrointestinal tract (n = 71) included 21% adenomatous polyps, 21% internal hemorrhoids, 15% diverticulosis, 7% rectal varices, 3% colopathy, and 3% vascular ectasias. Univariate analysis revealed that there was a significant association between rectal varices and severe PHG (p < 0.05). This association was not maintained when multivariate analysis was performed.

CONCLUSIONS

Among all the findings, only rectal varices and colopathy were of higher prevalence in the pre-liver transplant population than that reported for the general population. No significant associations were found between these gastrointestinal tract lesions and patient characteristics.

Unfolding of acrylodan-labeled human serum albumin probed by steady-state and time-resolved fluorescence methods

Steady-state and time-resolved fluorescence spectroscopy was used to follow the local and global changes in structure and dynamics during chemical and thermal denaturation of unlabeled human serum albumin (HSA) and HSA with an acrylodan moiety bound to Cys34. Acrylodan fluorescence was monitored to obtain information about unfolding processes in domain I, and the emission of the Trp residue at position 214 was used to examine domain II. In addition, Trp-to-acrylodan resonance energy transfer was examined to probe interdomain spatial relationships during unfolding. Increasing the temperature to less than 50 degrees C or adding less than 1.0 M GdHCl resulted in an initial, reversible separation of domains I and II. Denaturation by heating to 70 degrees C or by adding 2.0 M GdHCl resulted in irreversible unfolding of domain II. Further denaturation of HSA by either method resulted in irreversible unfolding of domain I. These results clearly demonstrate that HSA unfolds by a pathway involving at least three distinct steps. The low detection limits and high information content of dual probe fluorescence should allow this technique to be used to study the unfolding behavior of entrapped or immobilized HSA.

Transjugular intrahepatic portosystemic shunt patency and the importance of stenosis location in the development of recurrent symptoms

PURPOSE

To analyze in detail the location and types of stenosis and occlusion that occur after transjugular intrahepatic portosystemic shunt (TIPS) creation and to determine the relative contribution of these various types of TIPS malfunction to recurrent symptoms of variceal bleeding or ascites.

MATERIALS AND METHODS

In 116 of 217 patients who underwent TIPS creation between June 1990 and July 1995, follow-up portal venography was performed at 6-month intervals and for symptoms of recurrent variceal bleeding or ascites.

RESULTS

Cumulative primary venographic patency by means of Kaplan-Meier survival analysis was 55% at 6 months and 5% at 2 years. Secondary patency was 92% at 2 years. Stenosis or occlusion occurred in 63 of 116 patients (54%). In 20 patients (17%), acute shunt occlusions developed less than 30 days after TIPS creation; in 24 patients (21%), tract abnormalities were detected after 30 days; and in 19 patients (16%), hepatic vein stenoses were detected after 30 days. Abnormalities of the parenchymal tract were more often correlated with recurrent variceal bleeding or ascites than were hepatic vein stenoses (odds ratio, 3.6; P = .02). Ten of 14 patients (71%) with detected biliary fistulas to their TIPS had symptoms, and all patients with biliary fistulas had tract abnormalities.

CONCLUSION

Tract stenoses and occlusions were the major cause of symptomatic shunt failure after TIPS creation. Substantial bile duct transections are often associated with tract abnormalities and recurrent symptoms. Although common, hepatic vein stenoses were rarely associated with recurrent symptoms in our patient population.

Hepatic iron overload: direct HFE (HLA-H) mutation analysis vs quantitative iron assays for the diagnosis of hereditary hemochromatosis

Among patients with hepatic iron overload, the distinction between hereditary hemochromatosis (HH), a common yet treatable genetic disease, and other causes of siderosis remains problematic. The recent discovery of a specific homozygous mutation (C282Y) in a novel major histocompatibility complex class I-like gene (named HLA-H or HFE) in 80% to 100% of well-characterized cases of HH suggests that direct DNA-based mutation analysis may help resolve this dilemma. To assess the clinical utility of direct HLA-H mutation analysis in a typical diagnostic setting, we measured genotypic and phenotypic parameters of iron overload in 37 subjects with biopsy-proven hepatic siderosis (2+ or greater) and in 127 healthy control subjects. The prevalence of C282Y homozygotes was significantly greater in the hepatic siderosis group (32%) than in the control group (0%), confirming the association between this homozygous mutation and hepatic iron overload. In the hepatic siderosis group, C282Y homozygotes had significantly higher hepatic iron and ferritin levels, a significantly lower prevalence of hepatitis C virus or alcoholic liver disease, but no significant difference in the saturation of serum transferrin. Of the 20 subjects with a hepatic iron index (HII) in the previously defined "hemochromatosis range" (>1.9), 9 (45%) were C282Y homozygotes. Of the 11 nonhomozygous subjects with an HII greater than 1.9 (presumed false-positive HIIs), 10 (91%) had hepatic cirrhosis compared with 3 of 9 (33%) homozygotes with an HII greater than 1.9 who had cirrhosis (P<.02). The HII thus has poor diagnostic specificity for predicting genotypic HH in patients with cirrhosis. We conclude that direct determination of the HLA-H C282Y genotype may be the single best diagnostic test for HH, particularly in patients with cirrhosis, for whom the HII is quite nonspecific.

Milk thistle (Silybum marianum) for the therapy of liver disease

Silymarin, derived from the milk thistle plant, Silybum marianum, has been used for centuries as a natural remedy for diseases of the liver and biliary tract. As interest in alternative therapy has emerged in the United States, gastroenterologists have encountered increasing numbers of patients taking silymarin with little understanding of its purported properties. Silymarin and its active constituent, silybin, have been reported to work as antioxidants scavenging free radicals and inhibiting lipid peroxidation. Studies also suggest that they protect against genomic injury, increase hepatocyte protein synthesis, decrease the activity of tumor promoters, stabilize mast cells, chelate iron, and slow calcium metabolism. In this article we review silymarin's history, pharmacology, and properties, and the clinical trials pertaining to patients with acute and chronic liver disease.

Effect of oral sodium phosphate colon preparation on serum electrolytes in patients with normal serum creatinine

BACKGROUND

Oral sodium phosphate is commonly used for colon preparation prior to colonoscopy. Several studies have demonstrated significant changes in serum electrolytes after sodium phosphate preparation, but failed to stratify patients with regard to renal function. The purpose of this study was to determine if electrolyte alterations are observed after sodium phosphate in patients with normal levels of serum creatinine.

METHODS

Thirty-two patients scheduled for elective colonoscopy who had a serum creatinine level of less than 1.5 mg/dL were enrolled. All patients had a panel of laboratory studies prior to and immediately after receiving oral sodium phosphate colon preparation.

RESULTS

Significant increases in serum phosphate and sodium and decreases in serum calcium and potassium were observed. Twenty-eight percent of patients had serum phosphate levels greater than 8.0 mg/dL, and 6% of patients had serum calcium levels less than 8.0 mg/dL after sodium phosphate colon preparation. There were no clinically apparent adverse events.

CONCLUSIONS

Significant changes in serum electrolyte levels occur after sodium phosphate colon preparation in patients with normal serum creatinine levels. Sodium phosphate could exacerbate pre-existing hypocalcemia or hypokalemia in patients with apparently normal renal function. Therefore, it may be prudent to evaluate serum electrolytes prior to administration of sodium phosphate.

An outbreak of acute hepatitis C among recipients of intravenous immunoglobulin

BACKGROUND

An association between therapy with intravenous immunoglobulin (IVIG, Gammagard, Baxter Healthcare Corp) and acute hepatitis C (HCV) was reported by the manufacturer in 1994.

OBJECTIVE

We sought to describe those patients at risk at our institution who developed HCV infection after IVIG (Gammagard) treatment(s).

MATERIALS

An inception cohort study of patients with exposure to contaminated IVIG in a university tertiary care institution. Twenty-three patients received suspect IVIG and presented to be screened for HCV via ELISA II and polymerase chain reaction techniques. We describe the demographics and clinical characteristics of patients diagnosed with hepatitis C infection from IVIG.

RESULTS

Ten of 23 (44%) patients who had received immunoglobulin (2 g/kg) for neurologic or immunologic disorders and were tested for anti-HCV were positive. All were also HCV-RNA positive by polymerase chain reaction. None had other HCV risk factors; all but two had normal aminotransferases documented prior to therapy. The patients had received monthly therapy for periods ranging from 2 to 60 months. Four patients were asymptomatic and the others had mild symptoms. One patient spontaneously became PCR negative within 12 months after exposure.

CONCLUSION

Patients who received intravenous immunoglobulin (Gammagard, Baxter Healthcare Corp) between March, 1993, and February, 1994, are at risk for acute hepatitis C. The initial sequellae appear to be mild and spontaneous remission is possible.

Didemnin B. The first marine compound entering clinical trials as an antineoplastic agent

A new class of marine compounds, the didemnins, with potent antitumor activity has been identified. They share the novel structure of a cyclic depsipeptide. Among three structurally related compounds, didemnin B is by far the most potent in its in vitro cytotoxicity and in vivo antitumor activity (0.001 microgram/ml inhibits the growth of L1210 leukemia cells by 50%). It also demonstrates good antitumor activity against B16 melanoma and moderate activity against M5076 sarcoma and P388 leukemia. The compound also has good antiviral and potent immunosuppressive properties. Although the precise mechanism of action for the cytotoxicity remains unknown, the agent inhibits protein synthesis more than DNA synthesis and the inhibition of protein synthesis is closely correlated with inhibition of L1210 cell growth. Toxicology studies in CD2F1 mice, Fischer 344 rats and beagle dogs reveal that major target organs are the lymphatics, gastrointestinal tract, liver and kidney. Phase I trials are currently in progress under the auspices of the National Cancer Institute.

Comparison of the analysis of delta 9-tetrahydrocannabinol capsules by high-performance liquid chromatography and capillary gas chromatography

The modification of a high-performance liquid chromatography (HPLC) system and the development of a capillary gas-chromatographic (GC) system for the analysis of delta 9-tetrahydrocannabinol, encapsulated in soft gelatin capsules, are described. A photodiode array detector was used to evaluate peak homogeneity after each HPLC system modification. Sesame oil was separated from the extract by Sep-Pak filtration prior to GC analysis. Quantitation by both systems had r values greater than 0.999 and R.S.D. values less than 1.0%. Simultaneous capsule assays by both methods agreed within 1%.