Antimigration versus conventional fully covered metal stents in the endoscopic treatment of anastomotic biliary strictures after deceased-donor liver transplantation.

INTRODUCTION: Migration of fully covered metal stents (FCMS) remains a limitation of the endoscopic treatment of anastomotic biliary strictures (ABS) following orthotopic liver transplantation (OLT). The use of antimigration FCMS (A-FCMS) might enhance endoscopic treatment outcomes for ABS. METHODS: Single center retrospective study. Consecutive patients with ABS following OLT who underwent ERCP with FCMS placement between January 2005 and December 2020 were eligible. Subjects were grouped into conventional-FCMS (C-FCMS) and A-FCMS. The primary outcome was stent migration rates. Secondary outcomes were stricture resolution, adverse event, and recurrence rates. RESULTS: A total of 102 (40 C-FCMS; 62 A-FCMS) patients were included. Stent migration was identified at the first revision in 24 C-FCMS patients (63.2%) and in 21 A-FCMS patients (36.2%) (p = 0.01). The overall migration rate, including the first and subsequent endoscopic revisions, was 65.8% in C-FCMS and 37.3% in A-FCMS (p = 0.006). The stricture resolution rate at the first endoscopic revision was similar in both groups (60.0 vs 61.3%, p = 0.87). Final stricture resolution was achieved in 95 patients (93.1%), with no difference across groups (92.5 vs 93.5%; p = 0.84). Adverse events were identified in 13 patients (12.1%) with no difference across groups. At a median follow-up of 52 (IQR: 19-85.5) months after stricture resolution, 25 patients (24.5%) developed recurrences, with no difference across groups (C-FCMS 30% vs A-FCMS 21%; p = 0.28). CONCLUSIONS: The use of A-FCMS during ERCP for ABS following OLT results in significantly lower stent migration rates compared to C-FCMS. However, the clinical benefit of reduced stent migration is unclear. Larger studies focusing on stricture resolution and recurrence rates are needed.

Changes in peripheral blood mononuclear cells glutamine synthetase mRNA after exercise in healthy volunteers: exploring an alternative proposal for non hepatic ammonia metabolism.

BACKGROUND: Glutamine synthetase (GS) plays a central role in the inter-organ metabolism of ammonia and hepatic encephalopathy. The main objective of the present work was to disclose the possible effect of exercise on GS mRNA expression in peripheral blood mononuclear cells (PBMC) within a group of healthy volunteers. MATERIAL AND METHODS: PBMC were studied instead of skeletal muscle because of ethical concerns. Characterization of GS in lymphocytes was carried out by indirect immunofluorescence and Western blot. After a pilot trial, expression of GS mRNA in PBMC was assayed by serial measurements in healthy volunteers who had exercised on a treadmill, and on a control group who had not. Muscle mass was estimated by bioimpedance. RESULTS: Cytoplasmic GS had a molecular weight of 44 kDa. Serial measurements of its mRNA demonstrated an increase in the treadmill (n = 29), but not in the control group (n = 13) (p < 0.05). Peak expression occurred at 1 h in males and at 6 h in females. There was a positive correlation between muscle mass and the increase of the enzyme mRNA after exercise. CONCLUSION: Exercise can increase the expression of GS mRNA in PBMC in healthy volunteers. Based on these preliminary results and on well-established physiological concepts, a hypothesis for non-hepatic ammonia metabolism is conceived. In the future could become part of the treatment of low-grade hepatic encephalopathy.

Validation of the psychometric hepatic encephalopathy score (PHES) for identifying patients with minimal hepatic encephalopathy.

BACKGROUND: The psychometric hepatic encephalopathy score (PHES) is a battery of neuropsychological tests used in the diagnosis of minimal hepatic encephalopathy (MHE). AIM: The aim of this study was to construct and validate a dataset of normal values for the PHES. METHODS: Volunteers and patients with cirrhosis with and without low-grade overt hepatic encephalopathy (OHE) were enrolled. All subjects completed the PHES battery, and possible modifying factors were assessed. Formulas to predict expected scores in cirrhotics were constructed, and MHE was diagnosed whenever a deviation of <-4 SDs occurred across the five tests. RESULTS: Among the 743 volunteers, age and years of education influenced the scores of all tests. Eighty-four patients with cirrhosis lacked evidence of OHE, whereas 20 had OHE: median PHES were -1 [0 to -3] and -9 [-6.5 to -11.8] (P < 0.001), respectively. Thirteen of the 84 patients (15%) with cirrhosis but without OHE had MHE. Patients with MHE were older and less educated than those without MHE (61 ± 8 and 52 ± 10 years old, P = 0.003; 7 ± 4 and 12 ± 5 years education, P = 0.002), whereas liver function was not different (MELD, 8 ± 5 and 8 ± 5). A very strong correlation between these norms and those derived from Spain was observed (r = 0.964, P < 0.001). CONCLUSIONS: PHES performance was mostly influenced by age and education, and expected results in cirrhotics need to be adjusted for these factors. Our validation of Mexican norms for PHES (PHES-Mex) establishes a practical method for assessing MHE and contributes to international attempts to standardize diagnostic protocols for MHE.

Autoimmune hepatitis with giant-cell transformation.

BACKGROUND/AIMS: Giant-cell hepatitis (GCH), also known as postinfantile or syncytial giant cell hepatitis, is a frequent pattern of liver injury in the neonate, primarily seen in the first three months of life. Few cases in adults have been reported, some of them associated to autoimmune diseases such as autoimmune hepatitis. METHODS: We present a case of autoimmune hepatitis with giant cell transformation in a 39 year old male with polyarthritis. We discuss his clinical presentation and course. We made a review of the literature of agents associated to this diagnosis, the mechanisms involved in the formation of giant hepatocytes, the histological findings, clinical course, treatment options and prognosis of this rare entity. RESULTS AND CONCLUSIONS: In conclusion, the clinical course varies from normalization of hepatic histology to progression to cirrhosis and liver failure. The prognosis is dictated by the underlying liver disease and in the setting of autoimmune hepatitis the clinical course is usually severe with most of the patients progressing to cirrhosis. Prolonged treatment with corticosteroids and immunosuppressants is usually effective in rendering the cirrhosis inactive.

Pathophysiology of ascites and dilutional hyponatremia: contemporary use of aquaretic agents.

Ascites, the most common complication of cirrhosis, is associated with a poor quality of life, an increased risk of infection, and renal failure. Twenty percent of cirrhotic patients have ascites at the time of diagnosis, while 30% and 50% will develop ascites by 5 and 10 years, respectively. There are several factors that contribute to ascites formation in cirrhotic patients, these include splanchnic vasodilatation, arterial hypotension, high cardiac output, and decreased vascular resistance. These factors lead to ineffective intravascular volume (hyperdynamic state), impairment of renal function, and subsequent water and sodium retention, all of which lead to dilutional hyponatremia (serum sodium <130 mEq/L), one of the most important prognostic factors in these patients. In conclusion, the therapeutic objective is to improve sodium balance and circulatory function through non-pharmacological measures, such as dietary sodium and water restriction as well as bed rest. Spironolactone (100-400 mg/day) is the initial drug of choice, while loop diuretics (like furosemide, 40-60 mg/day) are frequently used as adjuvants. Recently, agent that interfere with the renal effects of vasopressin by inhibiting water reabsorption in collecting ducts and producing free water diuresis have been used. These agents are called aquaretics and can be useful in the treatment o ascites unresponsive to conventional therapy.

[Evaluation of coronary flow by means of PET in the Mexican population without coronary artery disease]. / Valoración del flujo coronario mediante PET en lapoblación mexicana sin enfermedad arterial coronaria.

UNLABELLED: Coronary artery disease (CAD) represents the principal cause of morbidity and mortality in our environment. Positron emission tomography (PET) is a new technique in our country that allows the assessment of myocardial perfusion and the absolute quantification of the coronary blood flow (CBF) through the utilization of radiotracers using the same criteria employed in conventional nuclear cardiology. CBF normal values have been determined in other populations around the world. No studies in our country assessing in a non-invasive way the CBF have been published before. The quantification of CBF in healthy population is important to establish a standard measure and determine through it, the effects of the many diseases that change the coronary blood flow. The quantification of the CBF, the calculation of coronary blood flow reserve (CFR) and the endothelium dependent vasodilatation index (EDVI) through PET is possible performing three different acquisition stages: rest, cold pressor test (CPT) and pharmacologic stress using Ammonia as radiotracer. The aim of this study was to evaluate the CBF, the CFR and the EDVI in healthy Mexican volunteers. RESULTS: Global basal CBF was 0.34 (+/- 0.09) mL/g/min, during CPT increased to 0.55 (+/- 0.17) mL/g/min and during the stress increased to 1.18 (+/- 0.25). CFR was 3.5 (+/- 0.65) and EDVI was 1.55 (+/- 0.33). CONCLUSIONS: CFR and EDVI values obtained in Mexican healthy population correlates very well with those reported in the literature. This values represents a reference to further research that use this technology.

Valoración del flujo coronario mediante PET en la población mexicana sin enfermedad arterial coronaria / Evaluation of coronary flow by means of PET in the Mexican population without coronary artery disease

La enfermedad arterial coronaria (EAC) representa la primera causa de morbi mortalidad en nuestro medio. La tomografía por emisión de positrones (PET) es una técnica novedosa en nuestro país mediante la cual es posible valorar la perfusión miocárdica a través de radiotrazadores, lo que permite detectar defectos de perfusión utilizando los mismos criterios que en cardiología nuclear. A su vez, a través del estudio del flujo coronario (FC) es posible detectar la EAC en sus etapas más tempranas. El FC ha sido determinado en otras poblaciones a nivel mundial, sin embargo, hasta el momento no existen estudios en nuestro país que lo hayan valorado de manera no invasiva. La importancia de determinar el FC en voluntarios sanos radica en establecer una base para poder comparar estos resultados con los encontrados en pacientes con diferente patología que afecte el flujo coronario. Para la determinación del FC y la reserva de flujo coronario (RFC) y del índice de vasodilatación dependiente de endotelio (IVED) mediante PET se realizan 3 mediciones en 3 fases distintas: reposo, estimulación con frío (CPT) y esfuerzo farmacológico, con la utilización de amonio. Objetivo: Determinar el FC en las tres fases en población sana con la utilización de amonio-PET. Resultados: El FC global basal fue de 0.34 (±0.09) mL/g/min, durante el CPT incrementó a 0.55 (±0.17) mL/g/min y con el estrés llegó a 1.18 (±0.25). La RFC fue de 3.5 (±0.65) y el IVED de 1.55 (±0.33). Conclusiones: Los valores obtenidos de RFC y de IVED en población mexicana sana coincide con los reportados en la literatura. Estos valores representan una base de referencia para las investigaciones futuras con esta tecnología en nuestro país.

Coronary artery disease (CAD) represents the principal cause of morbidity and mortality in our environment. Positron emission tomography (PET) is a new technique in our country that allows the assessment of myocardial perfusion and the absolute quantification of the coronary blood flow (CBF) through the utilization of radiotracers using the same criteria employed in conventional nuclear cardiology. CBF normal values have been determined in other populations around the world. No studies in our country assessing in a non-invasive way the CBF have been published before. The quantification of CBF in healthy population is important to establish a standard measure and determine through it, the effects of the many diseases that change the coronary blood flow. The quantification of the CBF, the calculation of coronary blood flow reserve (CFR) and the endothelium dependent vasodilatation index (EDVI) through PET is possible performing three different acquisition stages: rest, cold pressor test (CPT) and pharmacologic stress using Ammonia as radiotracer. The aim of this study was to evaluate the CBF, the CFR and the EDVI in healthy Mexican volunteers. Results: Global basal CBF was 0.34 (±0.09) mL/g/min, during CPT increased to 0.55 (±0.17) mL/g/min and during the stress increased to 1.18 (±0.25). CFR was 3.5 (±0.65) and EDVI was 1.55 (±0.33). Conclusions: CFR and EDVI values obtained in Mexican healthy population correlates very well with those reported in the literature. This values represents a reference to further research that use this technology.