Midodrine and albumin for prevention of complications in patients with cirrhosis awaiting liver transplantation. A randomized placebo-controlled trial

BACKGROUND & AIMS

Patients with decompensated cirrhosis on the waiting list for liver transplantation (LT) commonly develop complications that may preclude them from reaching LT. Circulatory dysfunction leading to effective arterial hypovolemia and activation of vasoconstrictor systems is a key factor in the pathophysiology of complications of cirrhosis. The aim of this study was to investigate whether treatment with midodrine, an alpha-adrenergic vasoconstrictor, together with intravenous albumin improves circulatory dysfunction and prevents complications of cirrhosis in patients awaiting LT.

METHODS

A multicenter, randomized, double-blind, placebo-controlled trial (NCT00839358) was conducted, including 196 consecutive patients with cirrhosis and ascites awaiting LT. Patients were randomly assigned to receive midodrine (15-30 mg/day) and albumin (40 g/15 days) or matching placebos for one year, until LT or drop-off from inclusion on the waiting list. The primary endpoint was incidence of any complication (renal failure, hyponatremia, infections, hepatic encephalopathy or gastrointestinal bleeding). Secondary endpoints were mortality, activity of endogenous vasoconstrictor systems and plasma cytokine levels.

RESULTS

There were no significant differences between both groups in the probability of developing complications of cirrhosis during follow-up (p = 0.402) or one-year mortality (p = 0.527). Treatment with midodrine and albumin was associated with a slight but significant decrease in plasma renin activity and aldosterone compared to placebo (renin -4.3 vs. 0.1 ng/ml.h, p < 0.001; aldosterone -38 vs. 6 ng/dl, p = 0.02, at week 48 vs. baseline). Plasma norepinephrine only decreased slightly at week 4. Neither arterial pressure nor plasma cytokine levels changed significantly.

CONCLUSIONS

In patients with cirrhosis awaiting LT, treatment with midodrine and albumin, at the doses used in this study, slightly suppressed the activity of vasoconstrictor systems, but did not prevent complications of cirrhosis or improve survival.

LAY SUMMARY

Patients with cirrhosis who are on the liver transplant waiting list often develop complications which prevent them from receiving a transplant. Circulatory dysfunction is a key factor behind a number of complications. This study was aimed at investigating whether treating patients with midodrine (a vasoconstrictor) and albumin would improve circulatory dysfunction and prevent complications. This combined treatment, at least at the doses administered in this study, did not prevent the complications of cirrhosis or improve the survival of these patients.

Ammonia induces aquaporin-4 rearrangement in the plasma membrane of cultured astrocytes

Aquaporin-4 (AQP4) is a water channel protein mainly located in the astroglial plasma membrane, the precise function of which in the brain edema that accompanies hepatic encephalopathy (HE) is unclear. Since ammonia is the main pathogenic agent in HE, its effect on AQP4 expression and distribution in confluent primary astroglial cultures was examined via their exposure to ammonium chloride (1, 3 and 5 mM) for 5 and 10 days. Ammonia induced the general inhibition of AQP4 mRNA synthesis except in the 1 mM/5 day treatment. However, the AQP4 protein content measured was dependent on the method of analysis; an apparent increase was recorded in treated cells in in-cell Western assays, while an apparent reduction was seen with the classic Western blot method, perhaps due to differences in AQP4 aggregation. Ammonia might therefore induce the formation of insoluble AQP4 aggregates in the astroglial plasma membrane. The finding of AQP4 in the pellet of classic Western blot samples, plus data obtained via confocal microscopy, atomic force microscopy (using immunolabeled cells with gold nanoparticles) and scanning electron microscopy, all corroborate this hypothesis. The effect of ammonia on AQP4 seems not to be due to any osmotic effect; identical osmotic stress induced by glutamine and salt had no significant effect on the AQP4 content. AQP4 functional analysis (subjecting astrocytes to a hypo-osmotic medium and using flow cytometry to measure cell size) demonstrated a smaller water influx in ammonia-treated astrocytes suggesting that AQP4 aggregates are representative of an inactive status; however, more confirmatory studies are required to fully understand the functional status of AQP4 aggregates. The present results suggest that ammonia affects AQP4 expression and distribution, and that astrocytes change their expression of AQP4 mRNA as well as the aggregation status of the ensuing protein depending on the ammonia concentration and duration of exposure.

Cognitive dysfunction in cirrhosis is associated with falls: a prospective study

Falls are frequent among patients with debilitating disorders and can have a serious effect on health status. Mild cognitive disturbances associated with cirrhosis may increase the risk for falls. Identifying subjects at risk may allow the implementation of preventive measures. Our aim was to assess the predictive value of the Psychometric Hepatic Encephalopathy Score (PHES) in identifying patients likely to sustain falls. One hundred and twenty-two outpatients with cirrhosis were assessed using the PHES and were followed at specified intervals. One third of them exhibited cognitive dysfunction (CD) according to the PHES (<-4). Seventeen of the forty-two patients (40.4%) with CD had at least one fall during follow-up. In comparison, only 5 of 80 (6.2%) without CD had falls (P < 0.001). Fractures occurred in 4 patients (9.5%) with CD, but in no patients without CD (P = 0.01). Patients with CD needed more healthcare (23.8% versus 2.5%; P < 0.001), more emergency room care (14.2% versus 2.5%; P = 0.02), and more hospitalization (9.5% versus 0%; P = 0.01) as a result of falls than patients without CD. Patients taking psychoactive treatment (n = 21) had a higher frequency of falls, and this was related to an abnormal PHES. In patients without psychoactive treatment (n = 101), the incidence of falls was 32.4% in patients with CD versus 7.5% in those without CD (P = 0.003). In the multivariate analysis, CD was the only independent predictive factor of falls (odds ratio, 10.2; 95% confidence interval, 3.4-30.4; P < 0.001). The 1-year probability of falling was 52.3% in patients with CD and 6.5% in those without (P < 0.001).

CONCLUSION

An abnormal PHES identifies patients with cirrhosis who are at risk for falls. This psychometric test may be useful to promote awareness of falls and identify patients who may benefit from preventive strategies.

Cerebral magnetic resonance imaging reveals marked abnormalities of brain tissue density in patients with cirrhosis without overt hepatic encephalopathy

BACKGROUND & AIMS

We applied advanced magnetic resonance imaging and Voxed based Morphometry analysis to assess brain tissue density in patients with cirrhosis.

METHODS

Forty eight patients with cirrhosis without overt hepatic encephalopathy (17 Child A, 13 Child B, and 18 Child C) and 51 healthy subjects were matched for age and sex. Seventeen patients had history of overt hepatic encephalopathy, eight of them had minimal hepatic encephalopathy at inclusion, 10 other patients had minimal hepatic encephalopathy at inclusion but without history of previous overt hepatic encephalopathy, and 21 patients had none of these features.

RESULTS

Patients with cirrhosis presented decreased brain density in many areas of the grey and white matter. The extension and size of the affected areas were greater in patients with alcoholic cirrhosis than in those with post-hepatitic cirrhosis and correlated directly with the degree of liver failure and cerebral dysfunction (as estimated by neuropsychological tests and the antecedent of overt hepatic encephalopathy). Twelve additional patients with cirrhosis who underwent liver transplantation were explored after a median time of 11months (7-50months) after liver transplant. At the time of liver transplantation, three patients belonged to class A of the Child-Pugh classification, five to class B and four to class C. Compared to healthy subjects, liver transplant patients showed areas of reduced brain density in both grey and white matter.

CONCLUSIONS

These results indicate that loss of brain tissue density is common in cirrhosis, progresses during the course of the disease, is greater in patients with history of hepatic encephalopathy, and persists after liver transplantation. The significance, physiopathology, and clinical relevance of this abnormality cannot be ascertained from the current study.

Minimal hepatic encephalopathy is associated with falls

OBJECTIVES

Minimal hepatic encephalopathy (MHE) reduces quality of life and impacts daily functioning. It is known to impair fitness to drive, but deficits in attention and reaction may also be associated with falls. Falls may have important consequences in patients with cirrhosis due to coagulopathy, osteoporosis, and operative risk. However, the relationship between MHE and falls has not yet been evaluated. The objective of this study is to retrospectively investigate whether MHE is associated with falls in patients with cirrhosis.

METHODS

We included 130 cirrhotic outpatients and 43 controls. MHE was diagnosed according to the results of the psychometric hepatic encephalopathy score (PHES). We recorded the reported incidence and number of falls in the 12 months before the study, the severity of injuries, and the need for healthcare services.

RESULTS

Forty-five (34.6%) patients with cirrhosis exhibited MHE. The proportion of patients with MHE that reported falls (40%) was higher than those without MHE (12.9%, P<0.001), which was similar to controls (11.6%). In patients with MHE, there was a higher need for primary healthcare services (8.8 vs. 0%, P=0.004) and hospitalization (6.6 vs. 2.3%, P=0.34) due to falls than in patients without MHE. Patients on psychoactive drugs (n=21) showed a stronger association between MHE and falls: 6/8 (75%) patients with MHE presented falls vs. 2/13 (15.3%) patients without MHE (P=0.01). In patients not receiving psychoactive drugs (n=109), the incidence of falls was 12/37 (32.4%) in patients with MHE vs. 9/72 (12.5%) in those without MHE (P=0.01). Multivariate analysis showed that MHE (odds ratio (OR): 2.91, 95% confidence interval (CI): 1.13-7.48, P=0.02), previous encephalopathy (OR: 2.87, 95% CI: 1.10-7.50, P=0.03), and antidepressant therapy (OR: 3.91, 95% CI: 0.96-15.9, P=0.05) were independent factors associated to previous falls.

CONCLUSIONS

Falls are more frequent in cirrhotic patients with MHE, particularly in those on treatment with psychoactive drugs, and are a significant cause for healthcare and hospitalization requirements.

Rat CCl(4)-induced cirrhosis plus total portal vein ligation: a new model for the study of hyperammonaemia and brain oedema

INTRODUCTION

Animal models used to study hyperammonaemic disorders related to chronic liver disease are unsatisfactory. These animals only develop hyperammonaemia and brain oedema when fed with diets supplemented with amonium acetate.

AIM

To develop a novel experimental model of hyperammonaemia and brain oedema in CCl(4)-induced cirrhosis in rats.

METHODS

Four groups were studied: rats with sham intervention (S), rats with total portal vein ligation (TPVL), cirrhotic rats (LC), and cirrhotic rats with TPVL (LC+TPVL). When ascites was diagnosed, oral glutamine challenge (OGC) test was performed. Blood, liver, lungs and brain samples were collected to quantify liver function parameters, plasmatic and cerebral ammonia, endotoxaemia, liver and brain histology, brain oedema and portosystemic shunting degree.

RESULTS

LC+TPVL rats showed a significant increase in portosystemic shunting when compared with LC group and a significant derangement in liver function when compared with TPVL group. These alterations resulted in a significant increase in plasmatic and brain ammonia concentrations and a higher plasmatic endotoxaemia as compared with others. Similarly, the area under OGC curve was significantly increased in LC+TPVL group as compared with the others, and correlates with portal shunting. Low-grade brain oedema was only observed in LC+TPVL group. All cirrhotic groups showed liver regeneration nodules and type-II Alzheimer astrocytes

CONCLUSION

LC+TPVL reproduce the main alterations - portosystemic shunting, plasmatic and cerebral hyperammonaemia and low-grade brain oedema - observed in cirrhotic patients with hepatic encephalopathy.

MR imaging findings in hepatic encephalopathy

The term hepatic encephalopathy (HE) includes a spectrum of neuropsychiatric abnormalities occurring in patients with liver dysfunction. Most cases are associated with cirrhosis and portal hypertension or portal-systemic shunts, but the condition can also be seen in patients with acute liver failure and, rarely, with portal-systemic bypass and no associated intrinsic hepatocellular disease. Although HE is a clinical condition, several neuroimaging techniques, particularly MR imaging, may eventually be useful for the diagnosis because they can identify and measure the consequences of central nervous system (CNS) increase in substances that under normal circumstances, are efficiently metabolized by the liver. Classic MR imaging abnormalities include high signal intensity in the globus pallidum on T1-weighted images, likely a reflection of increased tissue concentrations of manganese, and an elevated glutamine/glutamate peak coupled with decreased myo-inositol and choline signals on proton MR spectroscopy, representing disturbances in cell-volume homeostasis secondary to brain hyperammonemia. Recent data have shown that white matter abnormalities, also related to increased CNS ammonia concentration, can also be detected with several MR imaging techniques such as magnetization transfer ratio measurements, fast fluid-attenuated inversion recovery sequences, and diffusion-weighted images. All these MR imaging abnormalities, which return to normal with restoration of liver function, probably reflect the presence of mild diffuse brain edema, which seems to play an essential role in the pathogenesis of HE. It is likely that MR imaging will be increasingly used to evaluate the mechanisms involved in the pathogenesis of HE and to assess the effects of therapeutic measures focused on correcting brain edema in these patients.

Development of a clinical hepatic encephalopathy staging scale

AIM

To develop a scale to assess the severity of hepatic encephalopathy using simple dichotomic items.

METHODS

A list of 48 items was created by selecting items that are simple to recognize and categorize; it was applied to thirty-six cirrhotic in-patients with episodic encephalopathy, in addition to the adapted-West-Haven Criteria and the Glasgow Coma Score. The list underwent an item reduction process and principal component analysis; the metric characteristics were evaluated.

RESULTS

Multiple neurological abnormalities were observed and a Clinical Hepatic Encephalopathy Staging Scale of nine items was constructed. The principal component analysis of the Clinical Hepatic Encephalopathy Staging Scale obtained two factors that explained 77% of the variance. The Clinical Hepatic Encephalopathy Staging Scale exhibited adequate internal consistency and reproducibility. The scores of the Clinical Hepatic Encephalopathy Staging Scale correlated to those of adapted-West-Haven Criteria and the Glasgow Coma Score.

CONCLUSIONS

This study confirms that the evaluation of multiple neurological manifestations is not necessary to classify hepatic encephalopathy adequately, which can be simply undertaken by an assessment of the patient's orientation, alertness, ability to respond to commands and to talk. A list of nine items is proposed as a linear scale from normality (Clinical Hepatic Encephalopathy Staging Scale = 0) to deep coma (Clinical Hepatic Encephalopathy Staging Scale = 9).

[Epidemiology of genotypic resistance of HIV-1 in Valencia. A 4-year study]

HIV resistance to antiretroviral drugs was studied in 348 samples taken from patients at the Molecular Biology Unit of the Microbiology Department of the Hospital La Fe, from January 2003 to July 2007. Once the viral load in plasma was determined, resistance was detected using complete gene sequencing for protease up to position 3464 of the HIV-1 reverse transcriptase gene. The results were analyzed using the Omiga 1.2 (Oxford Molecular Group) and HIV db Genotypic Resistance Interpretation Algorithm Version 4.3.0 (Stanford University) programs. The drugs least affected by the presence of mutations leading to resistance were the protease inhibitors darunavir, tripanavir and lopinavir (sensitivity >80%), the nucleoside reverse transcriptase inhibitors tenofovir and lamivudine (sensitivity >90%) and the non-nucleoside reverse transcriptase inhibitor TMC125 (sensitivity >80%).

Decrease in the volume of white matter lesions with improvement of hepatic encephalopathy

MR imaging has found abnormalities compatible with low-grade edema in the brain of patients with cirrhosis that have been related to hepatic encephalopathy. We present 3 patients with hepatic encephalopathy who exhibit supratentorial focal or diffuse white matter lesions compatible with small-vessel brain disease. The volume and number of white matter lesions reduced with the improvement of hepatic encephalopathy, suggesting the participation of the blood-brain barrier in the pathogenesis of brain edema in hepatic encephalopathy.

Pancreatic pseudocyst located in the liver

Pancreatic pseudocyst is a common complication of acute and chronic pancreatitis. Extrapancreatic locations of pancreatic pseudocyst in the liver, pleura, mediastinum, or pelvis have been described. However, a pancreatic pseudocyst located in the liver is an infrequent condition. We present the case of a 46-year-old man with pancreatic pseudocyst located in the liver secondary to chronic alcoholic pancreatitis. During admission, the patient underwent an abdominal CT scan that showed a mass located in the head and body of the pancreas, as well as a thrombosis of the splenic vein. A percutaneous needle aspiration biopsy of the pancreas was obtained under CT guidance, which showed no tumoral involvement. Fourty-eight hours after the procedure the patient developed abdominal pain and elevated serum amylase levels. A pancreatic MRI exam showed two pancreatic pseudocysts, one of them located in the left hepatic lobe, the other in the pancreatic tail. Chronic pancreatitis signs also were found. Enteral nutrition via a nasojejunal tube was administered for two weeks. The disappearance of the pancreatic pseudocyst located in the pancreatic tail, and a subtotal resolution of the pancreatic pseudocyst located in the liver were observed. To date twenty-seven cases of pancreatic pseudocyst located in the liver have been published, most of them managed with percutaneous or surgical drainage.

[Cytomegalovirus viral load and antigenemia in the monitorization of prophylactic treatment with valganciclovir in renal transplant recipients]

Cytomegalovirus (CMV) disease is one of the most relevant infectious complications in solid organ transplant, and we must perform an appropriate prophylactic intervention. The goal of this study was to evaluate the effectiveness of prophylactic treatment with valganciclovir in renal transplant recipients in the first three months post transplantation by shell vial urine culture assay, and by measuring antigenemia (pp65) and CMV viral load, the latter by PCR. The population of the study included 100 renal transplant recipients. We analyzed the results of 36 patients recruited between November 2003 and July 2004 who were receiving a prophylactic oral treatment with valganciclovir, and who had finished the follow-up period of 90 days. The three tests mentioned above were performed on days 7, 15, 30, 45, 60, 75 and 90. No positive antigenemia was detected, the virus was cultured in a urine specimen and, in one patient, three measurements of viral load in serum were positive. Preliminary results of the study suggest that universal chemoprophylaxis with valganciclovir is effective for the prevention of CMV infection in renal transplant recipients and that, although all three tests used were useful, the measurement of CMV viral load seems to be the most appropriate method for monitoring these patients.

[Immunomodulatory treatment with beta-interferon in patients with cervical intraepithelial neoplasia and human papillomavirus infection: long-term follow-up]

The aim of this study was to evaluate the long-term efficacy of beta-interferon treatment in the management of cervical intraepithelial neoplasia associated with human papillomavirus (HPV) infection in a selected group of patients. Thirty-nine patients who had histologically proven cervical intraepithelial neoplasia I or II with concurrent HPV infection were administered 27,000,000 IU of intramuscular beta-interferon. Periodical controls were carried out based on Papanicolaou smears and/or colposcopic examination and DNA HPV determination was performed by hybridation test, for a maximum of 8 years' follow-up. An initial complete response rate of 75% was obtained, with a recurrence rate of 25%, cervical intraepithelial neoplasia with late manifestation was of higher grade. Treatment interruption due to side-effects was not necessary. Associated viral infections appeared to be a recurrence risk factor, but not smoking or parity. While immunomodulatory treatment with beta-interferon has good long-term results in cervical intraepithelial neoplasia I/II treatment, wider randomized studies are required to obtain conclusive results.

[Cytomegalovirus nephrotic syndrome]

The case of a 5 months old infant with a nephrotic syndrome after neonatal cytomegalovirus infection is reported. Genomic amplification nested-PCR for CMV was positive in renal biopsy. Treatment with gancyclovir was effective to maintain nephrotic syndrome remission. We stresses the importance to discharge an infections cause of the nephrotic syndrome of newborns and infants due to the possibility on curative treatment.

[Haemophilus influenzae and betalactam resistance: description of bla TEM gene deletion]

The resistance to betalactam antibiotics in a total of 177 clinical isolates of Haemophilus influenzae, mostly from respiratory tract samples and characterized by their betalactamase production, was studied using the cephalosporin chromogenic assay and by detecting bla(TEM) and bla(ROB) genes. A substantial number of clinical isolates carrying the bla(TEM) gene, which presented a mutation consisting of the absence of a fragment of 136 base pairs, located upstream from the coding region including the 35 but not the 10 region of the promoter were found. This suggests that a new bla(TEM) promoter exists in these strains. This finding was associated with increased resistance to the antibiotics cefaclor and loracarbef compared with normal isolates. It was also found that 3.9% of the isolates carried the bla(ROB-1) gene.

[ROC curve analysis of factors predictive of response to treatment with interferon plus ribavirin in patients with chronic hepatitis C relapse after previous interferon treatment]

This study aimed to identify the factors predictive of response before the initiation of treatment and throughout the treatment period in patients with chronic hepatitis C relapse after treatment with interferon-a who were retreated with a standard regimen of interferon-a plus ribavirine and followed up for 40 months. Forty-four patients (40 with genotype 1, four without genotype 1) were included in the study. Four patients (genotype 1) were excluded because of adverse effects. The rate of maintained response was 55% (50% genotype 1, 100% non-genotype 1). The stage of histological damage (>2), glutamic-pyruvic transaminase (GPT) concentration (< or = 26 UI/l) and the association between the GPT concentration and the detection of the RNA-HCV in the first and third treatment months were the variables with an area under the ROC curve and a confidence interval >0.5. The probability of predicting a maintained response (negative predictive value) if the stage of histological lesion was <2 was 62.9%, while the positive predictive value was 100%. During the treatment, the disappearance of the RNA-HCV together with GPT values < or =26 in the first treatment month were the best predictive values. In this case, the negative predictive value was 78.3% and the positive predictive value was 76.5% (OR: 11.7, 2.6-52.2). Furthermore, the GPT value with the best predictive value (<26 UI/l) was a more effective predictor of the response to treatment than the normal value of the GPT. Finally, the GPT values >26 UI/l and the detection of RNA/HCV in the first or third treatment month were certain predictors of the absence of response but with low sensitivity (10-12%). It was concluded that is possible to predict the response to the combined treatment with an acceptable level of confidence, although not unequivocally. Ninety percent of the patients would be candidates for maintaining treatment for at least 6-12 months, while approximately 10% could undergo early interruption of treatment due to the absence of response.

[Retreatment with interferon plus ribavirin in chronic hepatitis C patients with genotype 1 who had no response or a relapse with a previous interferon treatment. Long term follow-up]

The aims of this study were twofold: i) to evaluate the sustained response rate at 6 months, at 12 months and at the end of the follow-up [(46.39 +/- 9.74 months) (range: 6-60 months)] in patients with chronic hepatitis C retreated with interferon-a (IFN-a) plus ribavirin for 6 months (group A), 12 months (group B), in patients with relapse and those with no response to a previous course of monotherapy with IFN-a; and ii) to evaluate changes in the histological liver lesion. One hundred and four patients (100 with genotype 1 and four without), 44 with relapse and 60 non-responders, were included. A total of 20.2% of the patients were excluded because of side effects. Fifty percent of the relapsing patients with genotype 1 showed a sustained response. The sustained response rate was higher in group B than in group A, whereas the rate for the relapsing patients was lower in group B than in group A (13/20 vs. 5/16; 7.2% vs. 61.5%; p <0.09 and p <0.009, respectively). However, 9.3% of the non-responding patients showed a sustained response (A/B: 2/2). The relapsing patients who had a genotype other than 1 showed a sustained response. The sustained response rate was constant throughout the follow-up, except in relapsing patients from group A (the late relapse rate was 28.6%). The viral load was not related to the response. The grade and stage of the histological lesion improved in patients with sustained response (n=20) and in one-third of the non-responding patients (n=45) (p <0.0001 and p <0.0001). IFN in combination with ribavirin was more effective in relapsing patients with genotype 1 at 12 months than in those at 6 months of treatment, whereas the effectiveness in non-responding patients was low. The sustained response evaluation at 6 months was reliable, except in relapsing patients with 6 months of treatment. The histological lesion improved significantly with combination antiviral therapy.

Normalization of T2 signal abnormalities in hemispheric white matter with liver transplant

OBJECTIVE

To determine whether edema can be assessed by MRI using T2-weighted signal intensity of hemispheric white matter in cirrhotic patients.

METHODS

Fast-FLAIR and magnetization transfer images were obtained before (24) and after (11) liver transplantation. T2-weighted abnormalities on baseline scans and their time-course changes were analyzed and compared with MT ratios (MTR).

RESULTS

Fast-FLAIR baseline images showed faint to substantial, bilateral, symmetric increased signal intensity along the hemispheric white matter in or around the corticospinal tract in 23/24 patients. After liver transplantation the signal abnormalities gradually recovered. This gradual decrease in signal intensity correlated with an increase in MTR values.

CONCLUSION

Asymptomatic symmetric high-signal intensity in the hemispheric white matter on fast-FLAIR MR images is present in cirrhosis. Normalization of this finding after successful liver transplantation and its correlation with MTR values suggest that this signal abnormality reflects mild edema.

[Study of the betalactam resistance of Haemophilus influenzae conferred by the bla(ROB-1) gene]

Given the lack of information on the resistance to betalactams conferred by the bla(ROB-1) gene in our area, we decided to undertake a study to determine if and how often it appears in our isolates. We analyzed the presence of the gene in 177 strains of Haemophilus influenzae and compared the results with those from the biochemical tests (nitrocefin). Sixty-three strains tested positive in the nitrocefin test (35.6%). The presence of the bla(ROB-1) gene was detected in seven of the 177 strains (3.9%). All the strains expressing the gene also tested positive in the nitrocefin test. Of the 63 strains that showed biochemical resistance (positive to nitrocefin), seven were found to be caused by the presence of the bla(ROB-1) gene. An epidemiological follow-up for the presence of this gene in our area is therefore advisable.

The development of low-grade cerebral edema in cirrhosis is supported by the evolution of (1)H-magnetic resonance abnormalities after liver transplantation

BACKGROUND/AIMS

Liver failure may cause brain edema through an increase in brain glutamine. However, usually standard neuroimaging techniques do not detect brain edema in cirrhosis. We assessed magnetization transfer ratio and (1)H-magnetic resonance (MR) spectroscopy before and after liver transplantation to investigate changes in brain water content in cirrhosis.

METHODS

Non-alcoholic cirrhotics without overt hepatic encephalopathy (n=24) underwent (1)H-MR of the brain and neuropsychological tests. (1)H-MR results were compared with those of healthy controls (n=10). In a subgroup of patients (n=11), the study was repeated after liver transplantation.

RESULTS

Cirrhotic patients showed a decrease in magnetization transfer ratio (31.5+/-3.1 vs. 37.1+/-1.1, P<0.01) and an increase in glutamine/glutamate signal (2.22+/-0.47 vs. 1.46+/-0.26, P<0.01). The increase in glutamine/glutamate signal was correlated to the decrease in magnetization transfer ratio and to neuropsychological function. Following liver transplantation, there was a progressive normalization of magnetization transfer ratio, glutamine/glutamate signal and neuropsychological function. Accordingly, correlations between these variables were lost after liver transplantation.

CONCLUSIONS

Cirrhotic patients show reversible changes in magnetization transfer ratio that are compatible with the development of low-grade cerebral edema. Minimal hepatic encephalopathy and low-grade cerebral edema appear to be the consequences of the metabolism of ammonia in the brain.

Altered content and modulation of soluble guanylate cyclase in the cerebellum of rats with portacaval anastomosis

It is shown that the glutamate-NO-cGMP pathway is impaired in cerebellum of rats with portacaval anastomosis in vivo as assessed by in vivo brain microdialysis in freely moving rats. NMDA-induced increase in extracellular cGMP in the cerebellum was significantly reduced (by 27%) in rats with portacaval anastomosis. Activation of soluble guanylate cyclase by the NO-generating agent S-nitroso-N-acetyl-penicillamine and by the NO-independent activator YC-1 was also significantly reduced (by 35-40%), indicating that portacaval anastomosis leads to remarkable alterations in the modulation of guanylate cyclase in cerebellum. Moreover, the content of soluble guanylate cyclase was increased ca. two-fold in the cerebellum of rats with portacaval anastomosis. Activation of soluble guanylate cyclase by NO was higher in lymphocytes isolated from rats with portacaval anastomosis (3.3-fold) than in lymphocytes from control rats (2.1-fold). The results reported show that the content and modulation of soluble guanylate cyclase are altered in brain of rats with hepatic failure, resulting in altered function of the glutamate-NO-cGMP pathway in the rat in vivo. This may lead to alterations in cerebral processes such as intercellular communication, circadian rhythms, including the sleep-waking cycle, long-term potentiation, and some forms of learning and memory.

Hepatic Encephalopathy

1. Acute Encephalopathy in Cirrhosis A. GENERAL MEASURES. Tracheal intubation in patients with deep encephalopathy should be considered. A nasogastric tube is placed for patients in deep encephalopathy. Avoid sedatives whenever possible. Correction of the precipitating factor is the most important measure. B. SPECIFIC MEASURES i. Nutrition. In case of deep encephalopathy, oral intake is withheld for 24-48 h and i.v. glucose is provided until improvement. Enteral nutrition can be started if the patient appears unable to eat after this period. Protein intake begins at a dose of 0.5 g/kg/day, with progressive increase to 1-1.5 g/kg/day. ii. Lactulose is administered via enema or nasogastric tube in deep encephalopathy. The oral route is optimized by dosing every hour until stool evacuation appears. Lactulose can be replaced by oral neomycin. iii. Flumazenil may be used in selected cases of suspected benzodiazepine use. 2. Chronic Encephalopathy in Cirrhosis i. Avoidance and prevention of precipitating factors, including the institution of prophylactic measures. ii. Nutrition. Improve protein intake by feeding dairy products and vegetable-based diets. Oral branched-chain amino acids can be considered for individuals intolerant of all protein. iii. Lactulose. Dosing aims at two to three soft bowel movements per day. Antibiotics are reserved for patients who respond poorly to disaccharides or who do not exhibit diarrhea or acidification of the stool. Chronic antibiotic use (neomycin, metronidazole) requires careful renal, neurological, and/or otological monitoring. iv. Refer for liver transplantation in appropriate candidates. For problematic encephalopathy (nonresponsive to therapy), consider imaging of splanchnic vessels to identify large spontaneous portal-systemic shunts potentially amenable to radiological occlusion. In addition, consider the combination of lactulose and neomycin, addition of oral zinc, and invasive approaches, such as occlusion of TIPS or surgical shunts, if present. Minimal or Subclinical Encephalopathy Treatment can be instituted in selected cases. The most characteristic neuropsychological deficits in patients with cirrhosis are in motor and attentional skills (60). Although these may impact the ability to perform daily activities, many subjects can compensate for these defects. Recent studies suggest a small but significant impact of these abnormalities on patients' quality of life (61), including difficulties with sleep (62). In patients with significant deficits or complaints, a therapeutic program based on dietary manipulations and/or nonabsorbable disaccharides may be tried. Benzodiazepines should not be used for patients with sleep difficulties.

De novo hepatitis B after liver transplantation from hepatitis B core antibody-positive donors in an area with high prevalence of anti-HBc positivity in the donor population

Transmission of hepatitis B virus (HBV) infection from donors who are negative for hepatitis B surface antigen (HBsAg-) but positive for antibody to hepatitis B core antigen (anti-HBc+) has been reported. However, previous studies were generally performed in geographic regions with a low prevalence of anti-HBc positivity in the liver donor population. The aims of this study are (1) to assess the risk for de novo hepatitis B in recipients of livers from anti-HBc+ donors in an area of high prevalence of anti-HBc positivity in the donor population, and (2) to analyze the risk factors for acquisition of HBV infection from anti-HBc+ donors. The transplantation experience of a single center between 1995 and 1998 was reviewed. Thirty-three of 268 liver donors (12%) were HBsAg- and anti-HBc+ during the study period. The proportion of anti-HBc+ donors increased with age; it was lowest (3.6%) in donors aged 1 to 20 years and highest (27.1%) in donors aged older than 60 years. Of the 211 HBsAg- recipients with 3 months or more of HBV serological follow-up, 30 received a liver from an anti-HBc+ donor and 181 received a liver from an anti-HBc- donor. Hepatitis B developed in 15 of 30 recipients (50%) of livers from anti-HBc+ donors but in only 3 of 181 recipients (1.7%) of livers from anti-HBc- donors (P < .0001). None of the 4 recipients who were antibody to HBsAg (anti-HBs)+ at the time of transplantation developed HBV infection after receiving a liver from an anti-HBc+ donor compared with 15 of 26 recipients (58%) who were anti-HBs- (P =.10). None of the 5 anti-HBc+ recipients developed hepatitis B compared with 15 of 25 anti-HBc- recipients (60%; P = 0.04). Child-Pugh score was significantly higher in recipients of livers from anti-HBc+ donors who developed HBV infection than in those who did not (9 +/- 2 v 7 +/- 1; P =.03). In our area, testing liver donors for anti-HBc is mandatory, particularly in older donors. With such information available, anti-HBc+ donors can be safely directed to appropriate recipients, mainly those with anti-HBs and/or anti-HBc at the time of transplantation. In the current era of donor shortage, this policy would allow adequate use of such donors.

Receiver operating characteristics curve analysis of factors predictive of nonresponse to interferon therapy in patients with chronic hepatitis C

OBJECTIVES

1) to identify pretreatment variables predictive of nonresponse to interferon-alpha (IFN-alpha) in patients with chronic hepatitis C, and 2) to establish a prognostic index in these groups using receiver operating characteristics curve analysis.

METHODS

132 patients were treated with IFN-alpha at a dose of 3 megaunits three times a week for 3-12 months. The response was compared in patients with a complete response vs nonresponders, and patients with a sustained response vs nonresponders plus relapsers. Factors predictive of response were identified by analyzing clinical, biochemical, virological and histological variables.

RESULTS

The sustained response rate was 12.8% at 24 months of follow-up. The pretreatment characteristics with a predictive value (PV) according to area under the ROC curve and 95% confidence interval > 0.5 were age, known duration of infection, history of transfusion, GGT, serum ferritin levels, viral load, genotype, and grade and stage of the histological lesion. The positive PV (the probability of predicting absence of response when the variable is present) was notably greater than the negative PV (mean: 94.9% vs 24.8%, respectively). In addition, when 4 and 6 variables were present, the positive PV was 100% and sensitivity was 60.2% and 22.1%, respectively. The predictive variables independently associated with an absence of response were genotypes 1, 4 and 5, GGT > 24 IU/l and grade of the histological lesion > 6.

CONCLUSIONS

It was possible to predict the absence of both primary and posttreatment response with an acceptable degree of reliability.

HCV-related fibrosis progression following liver transplantation: increase in recent years

BACKGROUND/AIMS

The natural history and predictors of HCV-related disease severity post-transplantation are uncertain. The aims of this study were to define the natural history of post-transplantation HCV infection by assessing the rate of fibrosis progression, to determine if the post-transplantation natural history differs from that observed pre-transplantation, and to identify predictors of post-transplantation disease progression.

METHODS

Post-transplantation biopsies (mean: 3+/-1.6/patient) from 284 patients were scored according to histologic stage, using the method of Desmet et al. Change in fibrosis score (fibrosis progression/year) post-transplantation was used as the primary outcome. Predictors analyzed included viral factors (genotype and viral load at transplantation), patient demographics, year of transplantation, country of transplantation, pre-transplantation fibrosis progression, immunosuppression and laboratory data.

RESULTS

There was a linear association between change in fibrosis score and time from transplantation, with a median rate of fibrosis progression per year of 0.3 (0.004-2.19/year). Using parametric time-to-event analysis, the expected median duration to cirrhosis was 10 years. The rate of post-transplantation fibrosis progression was significantly higher than pre-transplantation (0.2/year (0.09-0.8) p<0.0001), and higher in Spanish than US centers (0.48 (0.01-2.19) vs 0.28 (0.004-2.08); p=0.09) despite similar progression rates prior to transplantation. Variables independently associated with post-transplantation progression included year of transplantation (p=0.0001), race (p=0.02), number of methyl-prednisolone boluses (p=0.03), and HCV RNA levels at transplantation (p=0.01).

CONCLUSIONS

HCV-related disease progression is accelerated in immunocompromised compared to immunocompetent patients, with a progressive increase in patients who have recently undergone liver transplantation. Changes in patient management post-transplantation over time and between transplant centers may account for the increase in fibrosis progression observed in recent years.

[ROC curve analysis of factors predictive of non-response to interferon treatment in patients with chronic hepatitis C, genotype 1]

The objectives of this study included: 1) to identify pretreatment variables predictive of absence of response in 107 patients with chronic hepatitis C, genotype 1, treated with interferon-a (IFN-a) at a dose of 3 MU three times weekly for 3-12 months and classified into two groups: group A, nonresponders vs. patients with a complete response, and group B, nonresponding and relapsing patients vs. patients with a sustained response; and 2) to establish a prognostic index using ROC curve analysis. The rate of sustained response was 6. 5&#37; at the 24-month follow-up. The pretreatment characteristics with predictive value using ROC curves were as follows: in group A, age, GGT, serum ferritin, viral load, and grade and stage of the histological lesion; and in group B, known duration of infection, GPT, GGT, serum ferritin, viral load, and grade and stage of the histological lesion. In both group A and group B the positive predictive value (the probability of predicting an absence of response when the variable is present) was greater than the negative predictive value (mean: 84.3% vs. 41.1%, 99% vs. 16.5%, respectively). In group A, based on the prognostic index, the positive predictive value when three variables were present was 96&#37; and the sensitivity was 63.5&#37;, with the test being unequivocal in 6.5&#37;, whereas when four or five variables were present, the positive predictive value was 97&#37; and 100&#37; and the sensitivity was 40.5&#37; and 18&#37;, respectively. In group B, the positive predictive value when two variables were present was 100&#37; and the sensitivity was 87&#37;, whereas when three, four, five and six variables were present the sensitivity was between 73&#37; and 28&#37;. In group A, age, GGT and ferritin were the predictive variables independently associated with an absence of response, with a relative risk of 6.5, 4.8 and 3.1, respectively, whereas in group B we did not find variables independently associated with an absence of response. It was concluded that in patients with genotype 1, it is possible to predict the absence of response to IFN therapy with a high degree of reliability.

[Comparative analysis of viral load by bDNA HCV RNA-2.0 and amplicor HCV monitor in patients with hepatitis C infection]

BACKGROUND

Two standardized techniques, Quantiplex (bDNA-2.0) and Amplicor Monitor have been evaluated for the quantification of virus load of HCV with these objectives: a) determinate the relationship between virus load and genotype, and b) evaluate the virus load in serial serum samples and in patients with normal or slightly increased liver enzymes in an area with a high prevalence of genotype 1.

RESULTS

A significant correlation of 0.7 (p < 0.0001) in virus load has been observed by both methods, but the virus load is smaller by Monitor than by Quantiplex and does not depend on genotype. The relationship Monitor/Quantiplex is smaller in patients with non-1 genotype than in patients with genotype 1a (p = 0.01) and 1b (p = 0.005). Virus characteristics are similar in patients with normal or slightly increased enzymes than in patients with high enzymes. Virus load by both methods is not related to the age, sex, know duration of the infection, transmission manner of the infection neither to the histologic activity index.

CONCLUSION

The virus load not depends on genotype. The determination of virus load in a single serum sample adequately reflects the virus load are in several serum samples in patients with chronic HCV infection. The genotype and the virus load are similar in patients with normal enzymes than in patients with high enzymes.

[Early prediction of lack of response to treatment with interferon and interferon plus ribavirin using biochemical and virological criteria in patients with chronic hepatitis C]

The objectives of this study were the following: 1) to evaluate the predictive value of the detection of RNA-HVC compared to GPT in the third month of treatment in patients with chronic hepatitis C treated with IFN, and at the first and third month in patients treated with IFN and ribavirin for 6 and 12 months. The study included: A) 80/132 patients treated with IFN (3 MU/3 times a week for 6-12 months), and B) 70/110 patients who had previously not responded to IFN, and who were treated with combination therapy (IFN: standard dose, ribavirin: 1200 mg/day) for 6 months (n = 40) and 12 months (n = 30). In group A, the positive predictive value (the probability of predicting the lack of response if the RNA-HVC was positive or if the GPT was elevated at the third month) was greater for RNA-HVC than for GPT (97.9% vs. 94.4%), although the response was not unequivocal (2.3% vs. 10.5%). The negative predictive value was 48.6% vs. 36.2%, respectively. The prediction level (odds ratio) of RNA-HVC and of GPT was 39.7 vs. 8.78 (p <0.000001 vs. p <0.002). The positive predictive value was 97.6% in patients with genotype 1, 4 and 5, and 100% in those with genotype 2 and 3. In group B, the positive predictive value was also greater for RNA-HVC than for GPT at the first month (100% vs. 94.4%) following six months of therapy, the odds ratio being infinite vs. 7.6. The positive predictive value was greater for RNA-HVC at the third month than at the first (100% vs. 91%), whereas it was similar for GPT (100%) with 12 months of therapy, the odds ratio being greater for GPT than for RNA-HVC at the first month (infinite and 7.27). The following was concluded: 1) detection of RNA-HVC at the third month of treatment with IFN predicts in advance a lack of response in patients, with a minimum risk of error; 2) in patients with six months of combined therapy, the detection of RNA-HVC at the first month is extremely reliable in the prediction of a lack of response, whereas after 12 months of combined therapy, elevated GPT values at the first month and the detection of RNA-HVC at the third are highly predictive of a lack of response.

Comparative analysis of quantification of viral load in patients infected with hepatitis C virus: quantiplex HCV RNA assay and amplicor monitor assay

OBJECTIVE

two standardized techniques, Quantiplex HCV RNA 2.0 (bDNA) and Amplicor Monitor, were evaluated for the quantification of hepatitis C virus (HCV) load. Our objectives were: 1) to determine the relationship between viral load and genotype, and 2) to evaluate viral load in serial serum samples and in patients with normal or slightly elevated liver enzyme values in an area with a high prevalence of genotype 1.

RESULTS

the viral loads detected with the two methods correlated significantly (r = 0.7, p < 0.0001), but viral load was smaller with the Monitor than with the Quantiplex assay, and was independent of genotype. The Monitor/Quantiplex ratio was lower in patients with a non-1 genotype than in patients with genotype 1b. Virological characteristics were similar in patients with normal or slightly elevated enzyme levels and in patients with elevated enzyme values. Neither method showed a relationship between viral load and age, sex, duration of the infection, mode of transmission, or histological activity index.

CONCLUSION

viral load was not dependent on genotype. Measurement of viral load in a single serum sample adequately reflected the viral load measured in several serum samples from patients with chronic HCV infection. Patients with normal liver enzyme levels are not good candidates, in virological terms, for treatment with interferon.

Value of the polymerase chain reaction assay in noninvasive respiratory samples for diagnosis of community-acquired pneumonia

We studied the causes of community-acquired pneumonia (CAP) in 184 patients. Microbiologic evaluation included sputum examination, blood culture, assessment of acute and convalescent antibody titers for Legionella pneumophila, Mycoplasma pneumoniae, Chlamydia pneumoniae, Coxiella psitacci, Coxiella burnetii and respiratory viruses, polymerase chain reaction (PCR) assays for M. pneumoniae and C. pneumoniae in throat swab, and PCR assay based on the amplification of pneumolysin gene fragment in sera. The causative pathogen was identified in 78 patients (Streptococcus pneumoniae, 44; M. pneumoniae, 26; C. pneumoniae, 1; others, 7). S. pneumoniae was detected in serum by the PCR assay in 41 patients, five of whom also had a positive blood culture. PCR assay was negative in two patients with positive blood culture for S. pneumoniae. C. pneumoniae was detected by PCR in nine patients, but only one showed seroconversion. M. pneumoniae was detected by PCR in only three patients (two without seroconversion). The diagnosis of pneumonia caused by S. pneumoniae was five times greater using PCR in serum than with blood culture. Detection of C. pneumoniae by PCR without fulfilling criteria for acute infection may be considered a prior infection. The PCR assay for the diagnosis of M. pneumoniae has a lower sensitivity than serologic methods.

Mild hypothermia modifies ammonia-induced brain edema in rats after portacaval anastomosis

BACKGROUND & AIMS

The pathogenesis of brain edema in fulminant hepatic failure is still unresolved. Mild hypothermia (33 degrees-35 degreesC) can ameliorate brain edema after traumatic brain injury. We evaluated mild hypothermia in a model of ammonia-induced brain edema in which accumulation of brain glutamine has been proposed as a key pathogenic factor.

METHODS

After portacaval anastomosis, anesthetized rats were infused with ammonium acetate at 33 degrees, 35 degrees, and 37 degreesC or vehicle at 37 degreesC. Water and glutamine levels in the brain, cardiac output, and regional and cerebral hemodynamics were measured when intracranial pressure increased 3-4-fold (ammonia infusion at 37 degrees) and matched times (other groups).

RESULTS

Mild hypothermia reduced ammonia-induced brain swelling and increased intracranial pressure. Brain glutamine level was not decreased by hypothermia. Brain edema was accompanied by a specific increase in cerebral blood flow and oxygen consumption, which were normal in both hypothermic groups. When the ammonia infusion was continued in hypothermic rats, plasma ammonia levels continued to increase and brain swelling eventually developed.

CONCLUSIONS

Mild hypothermia delays ammonia-induced brain edema. In this model, an increase in cerebral perfusion is required for brain edema to become manifest. Mild hypothermia could be tested for treatment of intracranial hypertension in fulminant hepatic failure.

[The effect of iron depletion on the response to interferon treatment in patients with chronic hepatitis C. Pilot study]

It has been reported that increase in serum ferritin levels and/or in hepatic iron content is associated with a poor response to interferon treatment in patients with chronic hepatitis C (CH-C).

AIM

To determinate whether iron depletion by phlebotomy (PB) increases the response to interferon therapy in chronic hepatitis C.

PATIENTS AND METHODS

We have evaluated 12 patients with CH-C (genotype 1b = 11, 1a = 1), increased ALT levels, positive serum VHC-RNA and increased serum ferritin levels (> 220 ng/ml), including 8 previously non responders to interferon therapy and 4 naive subjects. Phlebotomies were performed weekly (mean number per patient: 6, range: 5-12) until serum ferritin levels were < 100 ng/ml, followed by interferon treatment (3MU thrice weekly for 3-12 months depending on the response).

RESULTS

Multiple regression analysis showed that serum ferritin levels were not related to serum ALT levels (p = 0.18) or viral load (p = 0.06). Serum ALT levels decreased significantly post-PB (58 U/l, range: 35-141 U/l) as compared to pretreatment levels (164 U/l, range: 51-216 U/l, p < 0.006) and normalized in two subjects. HCV-RNA was positive in one of the latter and negative in the other. Eleven of the twelve patients did not respond to interferon after three months of therapy (increased serum ALT levels in 10 subjects and positive HCV RNA in 11). One additional patient, who had not been treated previously with interferon and had low pretreatment viral load, had a sustained response after 12 months of interferon therapy. Viral load did not decreased either with PB or following interferon treatment. By contrast, serum ferritin levels did not increase with interferon treatment or during the 6 month follow-up period.

CONCLUSIONS

Decreasing serum ferritin levels by phlebotomies does not increase HCV erradication rate after interferon treatment. Sustained response to interferon therapy is an infrequent event and is more dependent on viral factors (viral load and genotype).

High incidence of allograft cirrhosis in hepatitis C virus genotype 1b infection following transplantation: relationship with rejection episodes

The natural history of hepatitis C virus (HCV) infection following liver transplantation and predictors of disease severity remain controversial. The aims of the study were to assess in a homogeneous population of 81 cyclosporine-based HCV-infected liver transplant recipients mostly infected with genotype 1b and undergoing strict protocol annual biopsies: 1) the histological progression of posttransplantation HCV disease and, in particular, the incidence of HCV-related graft cirrhosis within the first 5 years after surgery; and 2) the relationship between progression to cirrhosis and i) rejection episodes and ii) first-year liver biopsy findings. We studied 81 consecutive HCV-RNA-positive patients (96% genotype 1b) undergoing liver transplantation between 1991 and 1996 with a minimum histological follow-up of 1 year. All patients received cyclosporine-based immunosuppression and underwent protocol yearly liver biopsies for the first 5 years. The mean histological follow-up was 32 months (range, 12-60 months). Biopsies were scored according to the histological activity index (HAI), with separate evaluation of grade (activity) and stage (fibrosis). Histological hepatitis, present in 97% of patients in the most recent biopsy, was moderate or severe in 64%. Twelve patients developed HCV-related cirrhosis at a median time of 24 months (range, 12-48 months), with an actuarial rate of HCV-cirrhosis of 3.7%, 8.5%, 16%, 28%, and 28% at 1, 2, 3, 4, and 5 years, respectively. Rejection was significantly more common among patients with cirrhosis versus those without (83% vs. 48%; P =.02), with an association between the incidence of cirrhosis and the number of rejection episodes: 5%, 15%, and 50% in patients without rejection, one and two episodes, respectively (P =.001). The degree of activity and fibrosis score in the first-year biopsy were higher in patients who developed cirrhosis than in those who did not (P =.008 and.18, respectively). In conclusion, HCV genotype 1b-infected liver recipients are at a high risk of developing graft cirrhosis in the first 4 to 5 years following transplantation, especially those with previous rejection episodes. First-year liver biopsies may help to sooner identify patients at the highest risk, improving further patient management.

Antibacterial and antifungal effects of soft contact lens disinfection solutions

AIMS

To study the antibacterial and antifungal effects of soft contact lens disinfection solutions.

METHODS

Eight contact lens disinfection solutions containing hydrogen peroxide or biguanides or polyquad compounds were evaluated with respect to their ability to disinfect a saline solution experimentally contaminated with different bacteria and with a fungus. We used cultures in blood Agar, MuellerHinton agar and Saboureaud's agar to identify the bacterial and fungal growth following 14 h of exposure to the disinfection solutions.

RESULTS

Hydrogen peroxide, DYMED and polyhexamide solutions prevented the growth of the four bacteria studied. The solution containing biguanide prevented the growth of Escherichia coli and Staphylococcus epidermidis. The solution with polyquad solution only prevented the growth of Staphylococcus epidermidis and none of the disinfection solutions prevented the growth of Candida albicans. The control solution, which was saline, did not prevent the growth of either bacteria or fungi.

CONCLUSIONS

Disinfection solutions containing hydrogen peroxide, or DYMED or polyhexamide can disinfect these four bacteria but none of them prevented the growth of Candida albicans.

[Evolution of resistance in the genus Enterococcus in strains isolated from blood]

The objective of this study was to determine the evolution of the species distribution and the prevalence of resistance to the Enterococcus genus. We studied 281 strains of enterococcus isolated from blood samples: 90 throughout 1984 and 791 from the years 1994 to 1996. identification was made using PosCombo 4Y Microscan-Baxter dehydrated panels and the Rapid ID 32 Strep system (bioMerieux). The MICs were calculated using the agar dilution method according to recommendations of the NCCLS for the following antibiotics: ampicillin, vancomycin, teicoplanin, gentamicin, kanamycin and streptomycin. The production of betalactamases were evaluated using a paper disk with nitrocefin for all the strains. The genotypes with resistance to glycopeptides were determined using PCR. The percentage of E. faecalis for 1984-1986/1994-1996 was 82.2/79.4; of E. faecium 4.4/16.4; and other species 12.214.3. The resistance to ampicillin went from 1.1% to 5.8%; high level resistance to glycopeptides went from 0% to 9.9%; for low level from 7.7% to 2.6%; resistance to a high charge of gentamicin went from 27.7% to 40.8%; and that for kanamycin from 45.5% to 62.8%. Resistance to streptomycin remained constant (45.5%). No strains produced betalactamases. For the species E. faecium, a statistically significant increase was detected for global resistance to ampicillin, gentamicin and kanamycin, with resistance to streptomycin remaining at similar percentages. No high level resistance to glycopeptides was detected in the first time period, but the low level resistance was greater.

Chronic hyponatremia exacerbates ammonia-induced brain edema in rats after portacaval anastomosis

BACKGROUND/AIM

Abnormalities in brain organic osmolytes are associated with hepatic encephalopathy and with chronic hyponatremia. In spite of the high frequency of hyponatremia in acute and chronic hepatic failure, its role in the development of neurological complications in liver disease is poorly understood. We aimed to study the effect of prior hyponatremia on the development of ammonia-induced brain edema in rats after portacaval anastomosis. In this model, brain swelling is mediated in part through an increase in brain glutamine, an organic osmolyte.

METHODS

Hyponatremia was induced in rats with 1-desamino-8-D-arginine vasopressin (DDAVP) administered through an osmotic minipump for 1 week. This was followed by performance of a portacaval anastomosis and ammonia infusion. At the end of the infusion, brain water (density gradient) and key brain organic osmolytes (HPLC) were measured.

RESULTS

Rats with hyponatremia showed a decrease in all three brain organic osmolytes measured: glutamine, myo-inositol and taurine. Hyperammonemia resulted in the expected rise in glutamine, with a reduction of myo-inositol and taurine. In the combined group (hyponatremia plus hyperammonemia), the rise in brain glutamine induced by ammonia infusion was attenuated (10.6+/-0.9 mM/kg vs. 15.5+/-0.8 mM/kg hyperammonemia alone; p<0.05). In spite of this limited rise in brain glutamine, ammonia infusion to hyponatremic rats exacerbated brain swelling (82.3+/-0.3% vs. 80.6+/-0.1%; p<0.05).

CONCLUSIONS

Hyponatremia worsens brain swelling in a model of ammonia-induced brain edema. The decrease in the concentration of brain organic osmolytes induced by hyponatremia does not protect the brain from the development of ammonia-induced brain edema.

[Prediction factors for lymph node involvement in carcinoma of the larynx]

A series of 60 patients with squamous cell carcinoma of the larynx who underwent surgery of the primary tumor and elective bilateral neck dissection were reviewed to determine the importance of certain clinical and pathological features as risk factors for lymph node metastasis. Tumor location, extension to the vallecula and to the pyriform sinus, T stage, histological grade, palpable lymph nodes, laryngeal motility, and macroscopic aspects were studied. Logistic regression analysis demonstrated that T stage, tumor location, and palpable lymph nodes were the most important predictors of lymph node metastases.

[Biological markers of alcohol abuse in patients with carcinoma of the larynx]

In a total of 85 patients with laryngeal carcinoma, four markers of alcohol abuse were analyzed. The Ggt and VCM were disturbed. We found no correlation between tumor location, lymph node metastases, T stage, and histological grade.

[Correlation of lymph node status with survival in cancer of the larynx]

A histopathological study of regional lymph nodes was made in 50 patients with squamous cell carcinoma of the larynx in order to evaluate their prognostic significance for survival. Factors related with poor prognosis were presence and number of lymph node metastases and capsule rupture. The presence and grade of sinus histiocytosis was related with survival. In multivariate analysis, the presence of five or more metastatic nodes had an independent influence on survival.

Early development of chronic active hepatitis in recurrent hepatitis C virus infection after liver transplantation: association with treatment of rejection

BACKGROUND/AIMS

We retrospectively studied 63 consecutive patients (mean age 54+/-8) with hepatitis C virus genotype 1b recurrence after liver transplantation and with a minimum histological follow-up of 1 year, in order to determine whether an early severe recurrence, defined as the development of chronic active hepatitis within the first 2 years post-liver transplantation, was associated with increased immunosuppression.

METHODS

The 1st year immunosuppression data (rejection episodes, boluses of methyl-prednisolone, cumulative doses of prednisone and azathioprine, OKT3 use) were recorded, and evaluated as predictive of severe recurrence at 1 and 2 years post-liver transplantation. Chronic active hepatitis and rejection were defined by histological criteria. Immunosuppression consisted of cyclosporine, azathioprine and prednisone. The treatment of rejection was based on a "bolus" of 1 g methyl-prednisolone/3 days.

RESULTS

At 1 year, 64% (40/63) of the patients had chronic active hepatitis, whereas of the 40 patients who had a 2nd year biopsy available, 75% had chronic active hepatitis at 2 years. At 1 year post-liver transplantation, no significant association was observed between immunosuppression and the development of chronic active hepatitis. In contrast, at 2 years, rejection (p=0.006), treatment of rejection (p=0.05), methyl-prednisolone boluses (p=0.013) and the number of rejection episodes (p=0.0034) occurring during the 1st year post-liver transplantation were significantly more common in patients with chronic active hepatitis. There was also a trend towards higher cumulative steroids (9447+/-3176.5 vs 7891.5+/-2111 mg) and higher cumulative azathioprine doses (13472+/-11154 vs 6233.5+/-5937 mg) in patients with chronic active hepatitis as compared to those who did not develop chronic active hepatitis.

CONCLUSIONS

Rejection and/or its treatment may accelerate the natural history of hepatitis C virus genotype 1b infection post-liver transplantation.