Natural history of clinically compensated hepatitis C virus-related graft cirrhosis after liver transplantation

The natural history of clinically compensated hepatitis C virus (HCV) cirrhosis after liver transplantation is unknown. This information is relevant to transplant centers to improve the management of these patients and decide the optimal timing for retransplantation. The aims of the study were (1) to describe the natural history of patients with HCV-cirrhosis transplants in a center with annual liver biopsies, and (2) to determine predictors for clinical decompensation, retransplantation, and mortality rates. A total of 49 patients with HCV-graft cirrhosis, 39 clinically compensated at histologic diagnosis of cirrhosis (post-liver transplantation cirrhosis) were included and followed up for 1 year (15 days-3.5 years). All patients tested were infected with genotype 1b. Predictive variables included histologic activity index (HAI) at post-liver transplantation cirrhosis, liver function tests, age, sex, and maintenance immunosuppression. Eighteen of 39 patients developed at least 1 episode of decompensation after a median of 7.8 months (4 days-2.6 years; 93% ascites). The cumulative probability of decompensation was 8%, 17%, and 42% at 1, 6, and 12 months, respectively. Graft and patient survival rates were 100%, 85%, and 71% and 100%, 92%, and 74% at 1, 6, and 12 months, respectively. Patient survival rates dropped significantly once decompensation developed (93%, 61%, and 41% at 1, 6, and 12 months, respectively). Variables associated with decompensation, retransplantation, and mortality rate included a high Child-Pugh score (>A), low levels of albumin at post-liver transplantation cirrhosis, and a short interval between liver transplantation and post-liver transplantation cirrhosis. The natural history of clinically compensated HCV-graft cirrhosis is shortened when compared with immunocompetent patients. If retransplantation is considered, it should be performed promptly once decompensation develops.

[Azathioprine and 5-ASA in the prevention of postoperative recurrence of Crohn's disease]

Recurrence of Crohn's disease (CD) lesions in the neo-ileum after apparently curative resection frequently occurs after surgery. The most appropriate prophylactic treatment has not been clearly defined. This study evaluated the efficacy of 5-ASA and azathioprine in decreasing postoperative recurrence and analysed the presence of variables associated with recurrence. Thirty-nine patients (mean age 32.8 years, range 18-61) with a history of ileal or ileocecal surgical resection were studied. They received 5-ASA (3 mg/day) or azathioprine (50 mg/day) immediately after the operation and for 2 years thereafter. Patients were followed clinically (Crohn's disease activity index) and serologically every 3 months and by imaging methods every 6 months. The latter included colonoscopy with ileoscopy and if not available, small bowel barium or ultrasonographic study. Laboratory tests included ESR, C-reactive protein, white blood cell and platelet count, fibrinogen and albumin. The end-point evaluated included clinical recurrence (CR), serological recurrence (SR: alteration of at least three of the above-mentioned variables) and morphologic recurrence (MR: endoscopic recurrence > 1 according to Rutgeerts score or radiological or ultrasonographic recurrence). Eighteen patients received azathioprine and 21 received 5-ASA. Thirty-four patients were evaluated. The cumulative proportion of patients with recurrence was 29% (CR), 35% (SR) and 50% (MR). Statistical analysis did not show significant differences between the two groups. Twenty-seven patients completed the 2-year study (11 in the azathioprine group and 16 in the 5-ASA group). Crude relapse rates were 37% (CR), 44% (SR) and 69% (MR) in the 5-ASA group and 36% (CR), 45% (SR) and 64% (MR) in the azathioprine group. No statistically significant differences were observed between groups. No variables associated with recurrence were detected. In conclusion, treatment does not prevent a high percentage of postsurgical recurrence. 5-ASA (3 g/day) and azathioprine (50 mg/day) showed similar efficacy in the prevention of recurrence.

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.

Two nitrate/nitrite transporters are encoded within the mobilizable plasmid for nitrate respiration of Thermus thermophilus HB8

Thermus thermophilus HB8 can grow anaerobically by using a membrane-bound nitrate reductase to catalyze the reduction of nitrate as a final electron acceptor in respiration. In contrast to other denitrifiers, the nitrite produced does not continue the reduction pathway but accumulates in the growth medium after its active extrusion from the cell. We describe the presence of two genes, narK1 and narK2, downstream of the nitrate reductase-encoding gene cluster (nar) that code for two homologues to the major facilitator superfamily of transporters. The sequences of NarK1 and NarK2 are 30% identical to each other, but whereas NarK1 clusters in an average-distance tree with putative nitrate transporters, NarK2 does so with putative nitrite exporters. To analyze whether this differential clustering was actually related to functional differences, we isolated derivatives with mutations of one or both genes. Analysis revealed that single mutations had minor effects on growth by nitrate respiration, whereas a double narK1 narK2 mutation abolished this capability. Further analysis allowed us to confirm that the double mutant is completely unable to excrete nitrite, while single mutants have a limitation in the excretion rates compared with the wild type. These data allow us to propose that both proteins are implicated in the transport of nitrate and nitrite, probably acting as nitrate/nitrite antiporters. The possible differential roles of these proteins in vivo are discussed.

Long-term effects of ursodeoxycholic acid in primary biliary cirrhosis: results of a double-blind controlled multicentric trial. UDCA-Cooperative Group from the Spanish Association for the Study of the Liver

BACKGROUND/AIM

The aim of this study was to assess the efficacy of ursodeoxycholic acid (UDCA) for primary biliary cirrhosis in a randomized, double-blind placebo-controlled trial.

METHODS

Consecutive patients (n=192) were randomized to receive 14-16 mg UDCA/kg/day or placebo. Patients underwent a complete history, physical examination, liver chemistries, immunological determinations and liver biopsy at entry and at the end of the trial, which lasted for at least 2 years. Patients were seen every 3 months and the median follow-up was 3.4 years (range 0.3 to 6.1 years).

RESULTS

Patients receiving UDCA (99) or placebo (93) were comparable with regard to age, sex, biochemical parameters and liver histology. UDCA treatment was associated with decreases in alkaline phosphatase, gammaglutamyl transferase, alanine aminotransferase, and cholesterol levels, effects which were conspicuous after 3 months of treatment and remained similar during the follow-up. During the study 31 patients (10 receiving UDCA and 21 placebo) discontinued the trial because of noncompliance (n=11), voluntary withdrawal (n=19) or adverse effects (n=1). Treatment failure (death or liver transplantation) was observed in 17 patients receiving UDCA and in 11 patients receiving placebo. Times to death or liver transplantation and to clinical complications were not significantly different in patients receiving UDCA or placebo. Histological analysis indicates that UDCA improved portal inflammation and prevented histological stage progression. By contrast, histological stage as well as ductular proliferation and ductopenia progressed in patients receiving placebo.

CONCLUSIONS

Although UDCA treatment did not significantly affect time to death or liver transplantation and to clinical complications, the effects on both cholestasis and liver histology suggest that UDCA is safe and may be useful for preventing the progression of primary biliary cirrhosis.

[Cyclosporin in an oral microemulsion as the initial treatment of corticoid-refractory ulcerative colitis]

AIM

To assess the efficacy of oral microemulsion cyclosporin as the initial treatment of active ulcerative colitis refractory to steroid therapy.

PATIENTS AND METHODS

The evolution of five patients treated with a dose of 5 mg/kg/day was analyzed.

RESULTS

Oral microemulsion cyclosporin controlled acute attacks of the disease and led to remission during the 3 months of treatment in four of the five patients. Average hospital stay was 5.5 days.

CONCLUSIONS

Oral microemulsion cyclosporin is an effective treatment in ulcerative colitis. Its administration is simple, the use of venous catheters is avoided and it may reduce mean hospital stay.

Cortical laminar necrosis caused by immunosuppressive therapy and chemotherapy

We report three patients in whom neurologic symptoms and cortical laminar necrosis developed after immunosuppressive treatment (cyclosporin A and FK 506) and polychemotherapy (vincristine and methotrexate). Initial neuroradiologic studies showed cortical and white matter involvement. Follow-up studies showed cortical hyper-intense lesions on T1-weighted MR images, consistent with cortical laminar necrosis. The clinical and radiologic data indicate that a transient hypoxic-ischemic process could have been responsible for the encephalic lesions in these three patients.

[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.

[Application of magnetic resonance spectroscopy in the study of brain disease]

INTRODUCTION AND OBJECTIVE

Magnetic resonance spectroscopy (MRS) is a non-invasive technique used for the neurochemical study of the brain in vivo. The aim of this work is to review the main investigations that have focused on the study of cerebral pathology.

DEVELOPMENT

Cerebral MRS studies started in 1983 but the maximum development has been in the 90's. The pathologies more investigated were Alzheimer's disease, multiple sclerosis, schizophrenia, and depression. Although several nuclei can be observed the most investigated are phosphor (P31) and hydrogen (H1). Nowadays proton MRS is the more frequently used technique. The low levels of N-acetyl-aspartate are a good indicator of neuronal loss. Their determination is complementary to the volumetric structural studies from magnetic resonance imaging. The peak of myo-inositol seems to be a neurochemical marker for the Alzheimer's disease.

CONCLUSIONS

MRS have contributed to the increase of knowledge about the physiopathology of normal aging, degenerative processes, demyelinating and psychiatric diseases. Potentially can contribute to differential diagnose in Alzheimer's and Parkinson's diseases. Recently it has also been opened a new research potential in the field of the pharmacological treatment effects in discrete cerebral regions.

Secretion and assembly of regular surface structures in Gram-negative bacteria

Bacteria synthesize large-sized surface structures through the ordered polymerization of protein subunits. This results in planar or tubular regular structures that have evolved to accomplish specific functions related to the particular environment in which these bacteria are found. Tubular assemblies known as flagella are the most complex structures known in bacteria and consist of a helical rigid filament, a torsion adapter or hook and a proton-fueled rotator known as the basal body. Pili or fimbriae are less complicated helical filaments, which consist of a major subunit and 3-5 minor subunits or pilins, whose main function is the attachment to specific surfaces. Planar structures known as S-layers are the simplest of these regular assemblies and are generally made up of a single subunit packed as a bidimensional crystal around the whole cell surface. Most of the components of these structures have to be secreted through the inner membrane (IM), the periplasm and the outer membrane (OM) before reaching their final destination. The so called general secretory pathway (GSP), or type II secretion system, appears to be implicated in this process to varying degrees, depending on the structure considered. A few S-layers and pili require GSP components but also need specific terminal branches, such as the well known chaperone-usher pathway. On the other hand, only two of the nearly 40 proteins involved in flagellar assembly are dependent on the GSP, while the external components are secreted through a specific pathway similar to the type III systems identified in some pathogens. Moreover, secretion of subunits of S-layers using dedicated type I machinery, without the involvement of any GSP component, has also been observed.

Intravenous cidofovir for compassionate use in AIDS patients with cytomegalovirus retinitis. Spanish Cidofovir Study Group

We report the compassionate use of intravenous cidofovir for the treatment of cytomegalovirus retinitis in 51 patients with AIDS who were receiving highly active antiretroviral therapy (HAART). After a median of 9 doses, 49 patients showed no retinitis activity. However, treatment was stopped in 17 patients because of adverse reactions and in 5 patients for other reasons. Two deaths were considered related to the drug. Iritis developed in 21 patients (41.2%), a frequency higher than that reported during the pre-HAART era. Patients with iritis had median CD4 cell counts-both at nadir and at the initiation of cidofovir therapy-approximately 3 times higher than those for patients without iritis (P=.003 and P=.05, respectively). Our study confirms the efficacy of cidofovir therapy for AIDS-associated cytomegalovirus retinitis. Our data suggest that the risk of iritis may be higher for patients with better immunological status, probably because of their enhanced ability to mount an inflammatory response.

[Acute intermittent porphyria: a possible cause of abdominal pain]

Acute intermittent porphyria (AIP) is an inherited disorder of heme metabolism. It can produce a variety of symptoms including abdominal pain. In Spain it is an uncommon disease and consequently may not be included in the differential diagnosis of acute abdominal pain. Two cases of AIP are reported, both of which started with recurrent abdominal pain. A brief commentary of the main topics of the disease is made with special emphasis on the importance of an early diagnosis.

Efficacy and safety of cardiomyotomy in patients with achalasia after failure of pneumatic dilatation

In patients with achalasia, it has been suggested that pneumatic dilatation could make cardiomyotomy more difficult to perform, diminishing its efficacy and safety. Our aim was to evaluate the efficacy and safety of elective cardiomyotomy after failure of pneumatic dilatation in achalasia. During 14 years, 32 of 276 consecutive patients with achalasia have been operated on because of failure of dilatation therapy. Twenty patients have been followed-up for at least one year after surgery. After failure of dilatation, Heller's cardiomyotomy and 180 degrees anterior fundoplication were performed. Clinical status was evaluated before and after surgery. Lower esophageal sphincter pressure and esophageal body basal pressure were measured by manometry, esophageal diameter by barium meal, and gastroesophageal reflux by endoscopy and 24-hr esophageal pH monitoring. No technical difficulties were found during operation. Postoperative morbidity was infrequent and mortality was absent. Cardiomyotomy improved clinical status in 19 of 20 patients. The results of surgery were considered excellent or good in 16 patients (80%; CI: 56-94%). The pressure of the lower esophageal sphincter was significantly reduced, falling in most patients to under 10 mm Hg. Gastroesophageal reflux appeared after surgery in eight patients, four of them with endoscopic esophagitis, but it was controlled in all patients with medical therapy. In conclusion, cardiomyotomy is a safe and effective therapy in achalasia after failed pneumatic dilatation.

A high-transformation-efficiency cloning vector for Thermus thermophilus

The cloning vector pMK18 was developed through the fusion of the minimal replicative region from an indigenous plasmid of Thermus sp. ATCC27737, a gene cassette encoding a thermostable resistance to kanamycin, and the replicative origin and multiple cloning site of pUC18. Plasmid pMK18 showed transformation efficiencies from 10(8) to 10(9) per microgram of plasmid in Thermus thermophilus HB8 and HB27, both by natural competence and by electroporation. We also show that T. thermophilus HB27 can take pMK18 modified by the Escherichia coli methylation system with the same efficiency as its own DNA. To demonstrate its usefulness as a cloning vector, a gene encoding the beta-subunit of a thermostable nitrate reductase was directly cloned in T. thermophilus HB27 from a gene library. Its further transfer to E. coli also proved its utility as a shuttle vector.

[Acute hepatitis due to heatstroke]

The hepatic injury is a nearly constant event in the course of a heatstroke, which rarely evolves to a severe liver failure. In these cases, the patient's survival is conditioned to an early treatment and, sometimes, an orthotopic liver transplantation is needed. We report a case of severe acute hepatitis in a 17-year-old man, due to a heatstroke during a vigorous exercise in a training program. High ambient temperature and a long time without training predisposed to the development of heatstroke in this patient. Outcome was favourably, with a total recovery in a few weeks.

[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.

Progression of cardiomyopathy and neuropathy after liver transplantation in a patient with familial amyloidotic polyneuropathy caused by tyrosine-77 transthyretin variant

Familial amyloidotic polyneuropathy is an inherited form of amyloidosis associated with a mutant form of a protein called transthyretin. The Methionine-30 variant is the most frequent mutation observed. This disorder is caused by deposition of this protein as amyloid in several organs, such as the heart, kidneys, and peripheral nervous system. The disease is always progressive and fatal, and patients die 7 to 10 years after the onset of symptoms. Liver transplantation is at present the only choice for these patients because it provides improvement of symptoms and/or stops progression of the disease in most patients. We report the case of a patient who showed clear progression of cardiomyopathy and neuropathy after liver transplantation.