Beneficial effect of carbohydrate maldigestion induced by a disaccharidase inhibitor (AO-128) in the treatment of chronic portal-systemic encephalopathy. A double-blind, randomized, controlled trial

BACKGROUND

The most widely used treatment of portal-systemic encephalopathy (PSE) is the administration of oral, non-absorbable disaccharides. Theoretically, the inhibition of intestinal disaccharidases should induce malabsorption of disaccharides and increase delivery of undigested carbohydrates to the colon, thus stimulating the effects of lactulose and other non-absorbable disaccharides (that is, lactitol and lactose). AO-128 is an N-substituted derivative of valeolamine, an aminocyclitol that selectively inhibits intestinal disaccharidases. This study was performed to investigate whether AO-128 could be used as adjuvant therapy for the treatment of mild PSE in cirrhotic patients.

METHODS

A double-blind, randomized, controlled trial was performed in 35 cirrhotic patients with PSE. Patients were given a 2-week treatment consisting of AO-128 (2 mg three times daily) or an identical placebo. The following features of PSE syndrome were assessed in a semiquantitative fashion before and after I and 2 weeks of therapy: mental state, asterixis, number connection test (NCT), venous blood ammonia concentration, electroencephalogram (EEG), and overall PSE index (PSEI). More patients receiving AO-128 than patients receiving placebo showed >40% improvement in the PSEI (83% versus 35%; P < 0.05). The mean stool pH decreased from 5.8+/-0.3 to 5.5+/-0.3 (P < 0.004) after AO-128 treatment, whereas no changes were observed in the placebo group. The EEG and nitrogen balance did not show significant changes in any of the two groups. A significant improvement was seen in the NCT performance after AO-128 (from grade 2.0+/-1.04 to grade 1.25+/-0.87; P < 0.05). Seven patients treated with AO-128 developed diarrhea, as compared with none in the placebo group (P < 0.05).

CONCLUSION

These results suggest that AO-128 may be useful in the treatment of PSE, although further studies are required to establish the benefit of AO-128 and determine adequate individual doses.

Risk factors for gallstone disease in Mexicans are similar to those found in Mexican-Americans

According to epidemiological studies, gallstone disease is a very common disease in Mexican-Americans and Mexicans. However, the major risk factors for cholelithiasis in Mexicans have not been identified. We designed a case-control study in a group of Mexican subjects with and without gallstone disease confirmed by ultrasound. These subjects were prospectively studied over a three-year period. Clinical and epidemiological data were collected by means of a questionnaire. A total of 1500 subjects were included in this study: 1000 with and 500 without gallstone disease. The major risk factor in both men and women was body mass index [odds ratio (OR) 1.64 and 1.96, respectively; P < 0.008 and 0.001]. In addition, parity was an important factor in women (OR 2.17, P < 0.001), whereas age was associated with gallstone disease in men (OR 1.43, P < 0.001). We found that body mass index, parity, and age were the principal risk factors for gallstone disease in this group of Mexican subjects. These results are similar to those found in Mexican-American populations.

The effect of uncertainty on the demand for medical care, health capital and wealth

We analyze the effect of the uncertainty of the incidence of illness on the demand for medical care and on the accumulation of health capital and wealth over the retirement years. We use a simplified version of a dynamic Grossman household production model to characterize patterns of an individual's precautionary behavior. Elderly individuals respond to uncertainty by smoothing their expected utility over time by making specific patterns of purchases of medical care and consumption. We examine these patterns for individuals with different degrees of risk aversion.

[Effects of fiber administration in the prevention of gallstones in obese patients on a reducing diet. A clinical trial]

Nearly 30% of the obese patients treated with hypoenergetic diets for weight reduction develop gallstone disease (GD). Until the present time, the use of ursodeoxycholic acid (UDA) is the only available therapeutic measure to avoid the development of GD. Dietary fiber induce a bile acid synthesis. A double-blind clinical trial was conducted to compare the effect of rational diet plus UDA vs a rational diet supplemented with Psyllium plantago (Pp) for the prevention of GD in obese subjects undergoing a weight-reduction diet. Patients with a body mass index (BMI = weight in Kg/square height in m) of 30 Kg/m2 or more and with normal gallbladder and biliary tree ultrasound (GBUS) were included. Weight-reduction diets were individually calculated for each patient according to their energy expenditure (EE). Patients were randomly and blindly assigned either to group I (diet + 750 mg UDA + fiber placebo) or group II (diet + 15 g Pp+ UDA placebo). An anthropometric evaluation was performed to each patient before and after the two-month treatment, as well as resting EE by indirect calorimetry, GBUS and endoscopy for the determination of cholesterol crystals in duodenal bile. Weight reduction was similar in both groups (group I = 6 +/- 2 Kg vs group II = 6 +/- 3 Kg). GD development was observed in one patient of group I (5.5%) and two patients of group II (p > 0.05). All patients with GD lost a minimum of 4 Kg during the study period. GD development did not correlate with the presence of crystals in the duodenal bile at the beginning of the study. Our results suggest a beneficial effect of a rational diet with fiber supplementation to prevent GD development in obese patients included in a weight reduction program.

Cholesterolosis is not associated with high cholesterol levels in patients with and without gallstone disease

High levels of cholesterol have been associated with certain gallbladder disorders such as cholesterolosis and gallstone disease. Furthermore, obesity is considered the main risk factor for cholesterol gallstone disease. We investigated the incidence of cholesterolosis in patients with and patients without gallbladder stones (GS). We reviewed the clinical records of patients with gallstone disease and other gallbladder disorders who had consecutive cholecystectomy during a 5-year period. We recorded demographic data, sex, age, serum cholesterol levels, and body mass index. The diagnosis of cholesterolosis was made macroscopically and microscopically. A total of 636 patients were included in this study: 446 with and 190 without GS. Cholesterolosis was more frequent in patients without GS (p < 0.01). However, hypercholesterolemia occurred more frequently in patients with GS (p < 0.001). Obese patients with GS had higher percentages of cholesterolosis and hypercholesterolemia than did eutrophic patients (p < 0.01 and p < 0.05, respectively). We suggest that cholesterolosis in the human gallbladder is not necessarily associated with gallstone disease and high plasma cholesterol levels.

Diagnostic value of the copper/zinc ratio in digestive cancer: a case control study

The aim of this study was to assess the accuracy of the copper/zinc ratio (Cu/Zn ratio) in the evaluation of a large group of patients with digestive cancer compared to gender and age-matched control subjects. A total of 282 patients was studied and separated into three groups: group I (n = 75), patients with digestive cancer, group II (n = 112), patients with benign digestive disease, and group III (n = 95), healthy subjects. Serum levels of copper and zinc were measured by atomic absorption spectrophotometry. The results showed that the serum levels of copper (mg/dL) in patients with digestive cancer (91.6 +/- 27.3, p < 0.05) were significantly higher than in patients with benign digestive disease (75.8 +/- 19.8) or healthy subjects (54.4 +/- 8.9) and the serum levels of zinc (mg/dl) were significantly lower (68.7 +/- 21.9, p < 0.05) compared to benign digestive disease patients (80.1 +/- 18.7) or healthy subjects (100 +/- 11.4 mg/dl). The Cu/Zn ratio was also significantly higher in patients with digestive cancer (1.45 +/- .58, p < 0.05) than those with benign digestive disease (0.95 +/- 0.28) or healthy subjects (0.55 +/- 0.13). Considering a cutoff value of 0.87, the sensitivity of the copper/zinc ratio was 82.2%, with a specificity of 65.7%, a positive predictive value of 45.8% and a negative predictive value of 91.3%. In conclusion, Cu/Zn ratio was found to be considerably higher in patients with digestive cancer compared to age- and gender-matched controls, with a sensitivity of 82.2% that might be useful in the evaluation of suspected malignancy.

[Chronology of portal hypertension, decreased sodium excretion, and activation of the renin-angiotensin system in experimental biliary cirrhosis]

OBJECTIVES

1) To evaluate the biochemical, renal, histological and splanchnic and systemic hemodynamic abnormalities induced by bile duct obstruction in rats, and 2) to study the temporal relationships between the start of portal hypertension, decrease of urinary sodium excretion and activation of the renin-angiotensin system.

METHODS

Bile duct obstruction was induced in 127 male Wistar rats, and renal function, hemodynamic, biochemical and liver histology were evaluated at weeks 1, 2, 3 and 4 after complete bile duct obstruction; the data were compared to that in 30 control rats.

RESULTS

Portal pressure significantly increased at week 1 (11.7 +/- 1.5. vs. 7.8 +/- 1.5 mmHg, p < 0.05) while the mean arterial pressure remained stable until week 4 when a slight decrease was observed (91.3 +/- 6.6 vs. 96.1 +/- 8.6 mmHg in control rats). A significant decrease in urinary sodium excretion was observed at week 1 (1.1 +/- 0.5 mEq/24 h) compared to control rats (2.3 +/- 0.6 mEq/24 h). In addition, hyperreninemia was observed at week 1 (5.1 +/- 0.2 vs. 2.4 +/- 1.3 ng Ang l/mL/h, p < 0.05) and hyperaldosteronism at week 2 (103 +/- 46 vs. 25.1 +/- 8.8 ng/24 h, p < 0.05) compared to control rats.

CONCLUSION

A temporal relationship between the beginning of portal hypertension and a decrease of renal sodium excretion, hyperreninemia and hyperaldosteronism was observed in bile duct ligated rats. This experimental model could be used to evaluate the effects of new drugs to prevent biliary cirrhosis including the abnormalities in the renal handling of sodium.

[Primary biliary cirrhosis: clinical features and survival of a Mexican population]

BACKGROUND

PBC progresses to cirrhosis and results in death due to liver failure or bleeding portal hypertension. Data of the clinical characteristics and survival of PBC patients allows the assessment of therapeutical alternatives as well as the establishment of inclusion criteria for liver transplantation.

AIMS

One hundred and twenty patients with histological diagnosis of PBC, admitted from 1972 to 1992, were selected with the purpose of studying the clinical and biochemical characteristics and survival.

METHODS

Patients who underwent liver transplant or those who had an incomplete follow-up were excluded.

RESULTS

Therefore only 80 patients were included: these were seventy five women and five men, with mean age 46 +/- 11 years (X +/- SD) to whom demographic data, biochemical analysis, liver function (Child-Pugh) and liver damage (Ludwig) were recorded at the time of histological diagnosis, which was considered zero for calculating the survival (Kaplan Meier). The most common symptoms at diagnosis were pruritus in 63 patients, jaundice in 48, asthenia and adynamia in 55 patients. Eight cases were asymptomatic. According to Child-Pugh's classification, patients were grouped as follows: forty in stage A, 29 in B, and three in C; and according to liver damage (Ludwig), 8 in grade I, 28 in grade II, 22 in grade III and 14 in grade IV. The most frequent clinical associations were Sjögren's syndrome, in 30% of patients, although one case was associated to progressive muscular dystrophy and another one to multiple myeloma and hypothyroidism; in 58.7% of the cases, antimitochondrial antibodies were negative. One year survival was 75%, five years 44%, and seven years 13%.

CONCLUSIONS

The most important characteristics of the studied patients were elevated percentage of negative antimitochondrial antibodies and short survival. it is important to impel the development of liver transplantation as the only mean to improve survival.

Similar fragmentation and dissolution after extracorporeal shock wave lithotripsy in eutrophic and overweight patients with gallstones

The aim of this study was to assess the relative importance of overweight and adjuvant treatment with bile acids to obtain fragment dissolution and clearance after biliary extracorporeal shock wave lithotripsy (BESWL), in eutrophic and overweight patients with gallbladder stones. During a 3-year period 103 patients were treated with BESWL. Patients were strictly selected in terms of the number and type of stones. Of the total of 103 patients, 53 were women and 50 men. Mean age was 50.8 +/- 14.3 (range 17 to 86) years. Body mass index was calculated for each patient. All patients underwent BESWL with an electromagnetic device. Medical therapy for stone dissolution included the combination of chenodeoxycholic acid plus ursodeoxycholic acid (50% + 50%), at a total dose of 10-15 mg/day. Of the 103 patients, 45 were eutrophic and 58 were considered overweight. Age was similar in both groups. Number of lithotripsy sessions in eutrophic patients was 1.96 +/- 1.07 and 1.88 +/- 0.84 in overweight patients, but no statistical differences were found. Complete clearance of calculi was observed in more than 50% of the cases after 6 months, and reached 98% after 22 months of therapy in both groups. Total clearance of calculi was similar in patients with single and multiple stones. In conclusion, our results suggest that the time required to obtain complete gallstone clearance after BESWL is similar in eutrophic and overweight patients with gallbladder stones, and also that adjuvant therapy with bile acids plays an important role in gallstone fragment dissolution in these patients.

[Experience of a single center in liver transplantation in adults and children]

Orthotopic liver transplantation (THO) is the treatment of choice for a variety of liver diseases. The national experience before 1993 has been scarce. In November 1993 we started our experience in THO at Clínica Las Condes, as part of a multiorgan transplant program (liver, kidney, pancreas). Until January 1995 we have performed 14 THO in 13 recipients (one retransplantation), of which 5 were in pediatric cases. The recipients range of age fluctuated between 1 and 61 years. In two pediatric cases a liver allograft reduction was performed. Six recipients (46%) required treatment for acute cellular rejection. One recipient had an hepatic artery thrombosis and had to be retransplanted. There was no operative mortality up to 30 days in cases of primary liver transplants. The retransplanted adult recipient, and another pediatric recipient that died from a late recurrence of a hepatoblastoma, accounted for the mortality of this experience. After an average follow up of 10 months, the actual patient survival in 85%. Of the 11 surviving recipients, 9 are in excellent conditions with a very good quality of life. This experience shows that an active liver transplant program in our country can be successful in obtaining results comparable to those published by very experienced foreign transplant centers.

[Hematological serological valves, and organ weight in adult Sprague-Dawley rats]

Sprague-Dawley rats are frequently used in experiments and their normal hematological, serologic and anatomical parameters are not easily available. The aim of this study was to measure these parameters in adult Sprague-Dawley rats. Twenty-four rats (12 males) whose weight ranged between 200 and 300 g, raised at the Instituto de Salud Pública in controlled environmental conditions and fed with pellets were studied. After a 24 h fast, animals were anesthetized with Droperidol and Ketamine, and after obtaining a cardiac blood sample, sacrificed by exsanguination. Most organs were withdrawn and weighed. Mean values for blood glucose, calcium, amylase, total proteins, cholesterol, AST, ALT, bilirubin, alkaline phosphatases, electrolytes and complete blood count were determined. Heart, lung, pancreas, kidney and testicle mean weight was also calculated. Male and female rats had significant differences in packed red cell volume, white blood cell count and hemoglobin.

Effects of ursodeoxycholic acid on hemodynamic and renal function abnormalities induced by obstructive jaundice in rats

The mechanism of renal function abnormalities in experimental biliary cirrhosis can be partially explained by the absence of gastrointestinal bile flow, which predisposes to translocation of intestinal endotoxin, a potent renal vasoconstrictor. Since bile acids prevent the absorption of intestinal endotoxins, we aimed to evaluate the effects of ursodeoxycholic acid (UDCA) administration on renal function and hemodynamic abnormalities induced by 1 week of obstructive jaundice in rats.

METHODS

Fifty-two rats were used; 30 had ligation of the common bile duct, 22 were sham operated. Bile duct ligated rats were randomly and blindly assigned to receive UDCA (25 mg/kg/day, n = 14) or placebo (n = 16) during 1 week. Sham rats received no treatment. Portal pressure (PP) as well as creatinine clearance (CrCl), urinary sodium (US), and plasma renin activity (PRA) were evaluated. Results are mean +/- SEM, with a significant value of p < 0.05.

RESULTS

Portal pressure (10.4 +/- 1.1 vs. 12.1 +/- 0.8 mm Hg) was significantly lower in UDCA than in placebo-treated rats. ALT serum levels were also significantly lower in bile duct ligated rats receiving UDCA (77.3 +/- 28 IU/L) than in placebo-treated rats (162 +/- 65 IU/L). US (1.1 +/- 0.5 vs. 2.1 +/- 0.3 mEq/24 h) was significantly lower and PRA (6.0 +/- 2.6 vs. 1.9 +/- 1.0 ng Ang 1/mL/h) higher in bile duct ligated than in sham-operated rats. No differences were found between UDCA or placebo-treated bile duct ligated rats. CrCl was similar between sham (0.39 +/- 0.12 mL/min/100 g BW) and UDCA (0.32 +/- 0.16) but significantly lower in placebo-treated (0.28 +/- 0.07) than sham-operated rats (p < 0.05).

CONCLUSION

UDCA administration had very mild effects on renal function abnormalities induced by experimental obstructive jaundice in rats. However, portal hypertension and biochemical abnormalities were partially improved.

Serum zinc concentrations in two cohorts of 153 healthy subjects and 100 cirrhotic patients from Mexico City

The aim of this study was to assess serum zinc levels in a cohort of healthy subjects and cirrhotic patients from Mexico City. A total of 153 healthy subjects and 100 cirrhotic patients, males and females aged 18-65, were studied. Inclusion criteria for healthy subjects were (1) Mexican-born with first and second generation relatives born in Mexico, and (2) somatometric (body mass index under 30) and clinical evaluation establishing that they had no underlying disease. Entry criteria for cirrhotic patients were (1) clinical and histological proven cirrhosis, (2) compensated liver disease (absence of coma, bleeding hemorrhage or refractory ascitis), and (3) cirrhosis of any cause. Zinc serum levels were measured with atomic absorption spectrophotometry. In healthy subjects, mean serum levels were 77.4 +/- 4.2 micrograms/dl (range 42.9-105.2 micrograms/dl). In cirrhotic patients zinc serum levels (58.9 +/- 16.1 micrograms/dl, range 22-88 micrograms/dl) were significantly lower than in healthy subjects (p < 0.05). A stepwise decline in serum zinc with worsening Child class (A, 73.4 +/- 13; B, 64.4 +/- 12; C, 55.8 +/- 15.6; p < 0.05 by ANOVA test) was found. In conclusion, this study confirms that zinc serum levels are significantly lower in cirrhotic patients and shows that zinc serum levels in a cohort of 153 healthy subjects from Mexico City were unexpectedly lower compared to those found in other countries. This last finding might be explained by different dietetic patterns and deserves further investigation.

A ten-year experience with hepatic resection in 338 patients: evolutions in indications and of operative mortality

OBJECTIVE

To report changes in indications for, and operative mortality of, elective hepatic resection during the 10 year period 1980-1989.

DESIGN

Retrospective study.

SETTING

District hospital.

SUBJECTS

338 consecutive patients who underwent elective hepatic resection.

INTERVENTIONS

During the first five years (1980-1984) 99 resections were done, 10 through a right thoracoabdominal incision, and the hepatic pedicle was clamped in 6. During the period 1985-1989 239 resections were done, only 7 (3%) through a thoracoabdominal incision, and the hepatic pedicle was occluded in 197 (82%).

MAIN OUTCOME MEASURES

Changes in indications for operation and operative technique, and mortality.

RESULTS

Indications for resection in the first period were: benign lesions (n = 39), primary hepatic cancer (n = 30-15 had hepatocellular carcinoma associated with cirrhosis), and metastatic disease (n = 30). Six patients died, five from uncontrollable bleeding during operation. Indications during the second half were: benign lesions (n = 105, 44%), primary hepatic cancer (n = 87, 36%-62 (29%) had hepatocellular carcinoma associated with cirrhosis), and metastatic disease (n = 47, 20%). There was only 1 death during operation (air embolism), and 9 cirrhotic patients died during the postoperative period.

CONCLUSIONS

More hepatic resections are being done and the indications are changing, with more patients with cancer and benign tumours being operated on; increasing use of pedicle occlusion has resulted in a significant decrease in uncontrollable operative bleeding; and mortality is still related to the presence of associated cirrhosis.

[Non-alcoholic fatty liver: 10 years' experience at the Insituto Nacional de la Nutrición Salvador Zubirán]

AIM

To describe the characteristics of non-alcoholic steatohepatitis (NASH) at the Instituto Nacional de la Nutricion Salvador Zubiran.

MATERIAL AND METHODS

We reviewed all liver biopsy reports from January 1982 to December 1991. From patient records we obtained the following data: clinical, biochemical, imaging studies and we reviewed the histological material. We correlated clinical, biochemical and histological data.

RESULTS

From 2963 biopsies reviewed we obtained 16 cases of NASH. We found a 7:1 female/male ratio. Median age was 30 years and six patients were obese. Eleven patients had concomitant disease (diabetes in seven) and nine were using drugs. All had been studied for biochemical abnormalities and were asymptomatic. Ten patients had hepatomegaly and six splenomegaly. Ultrasound suggested the diagnosis in 50% of the cases. All had steatosis, inflammatory infiltrate, necrosis, fibrosis and Mallory bodies at different stages. One case had cirrhosis on initial biopsy and two developed cirrhosis on follow-up (one and eight years later). We did not find any correlation between clinical, biochemical or imaging characteristics and histological findings. When we compared these findings between obese and non obese patients and primary and secondary NASH we did not find any differences between groups.

CONCLUSIONS

NASH is infrequent in our institution. The underlying pathogenesis seems to be multifactorial. There is no biochemical-histological correlation. Cirrhosis can develop in some cases.

[Prevalence of antinuclear antibodies in primary biliary cirrhosis, with negative antimitochondrial antibodies]

Recently it has been described in the literature a subpopulation of PBC patients with negative AMA that might represent patients with ANA positive autoimmune cholangitis. We review 25 cases of PBC (23 females) with AMA negative. Our aim was to determine the frequency of ANA(+) in this group. We studied serum transaminases, total bilirubin, AMA and ANA by indirect immunofluorescence considering positive dilutions of 1:40. All patients had elevated alkaline phosphatase (641 +/- 389 U/l). Total bilirubin was below 2.5 in 59%. Thirteen patients had esophageal varices. The histologic stage was I-II in eleven and III-IV in 14 cases. Fourteen patients (56%) has ANA(+) (dilution 1:40), 44% had lower dilutions. We confirm the presence of a subpopulation of PBC AMA negative, ANA positive patients and the observations of different and diverse immune alterations in PBC patients.

Prevalence of gallstone disease in Mexico. A necropsy study

The prevalence of gallstone disease in Mexico was investigated by studying a sample of 21,446 necropsies performed at the Department of Pathology of the General Hospital of Mexico City during a 35-year period (1953-1988). For each decade, 1000 necropsy cases were randomly selected. The crude prevalence of gallstone disease was 14.3%, 8.5% for males and 20.4% for females. The age groups ranged from 20 to more than 80 years old; the age-standardized prevalence for males was 5.6% and for females 16.2%. These rates are intermediate between those found in Chile and some African countries, comparable to some European studies, and less than those found in Mexican-Americans. No significant trend in the prevalence of gallstone disease was found when the different decades were compared.

[Assessment of knowledge of cardiopulmonary resuscitation]

The knowledge about standardized CPR of 41 physicians and 30 7th grade medical students was evaluated using a written multiple choice test. Results showed a severe lack of information about CPR in both groups; the test was approved by 39% of physicians and 10% of medical students. Among physicians, the lower achievements were obtained by traumatologists and the best by internists. The basic level of questions were approved by 63% of physicians and 43% of medical students. The principal deficiencies were on pharmacological management and CPR in trauma. It is concluded that education programs on CPR, similar to those given by the American Heart Association, are urgently needed among physicians and medical students.