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Biomedical subjects

V Arroyo

Publications and source records attributed to V Arroyo.

At least 235 records · Page 13Linked to original sources
PubMedDate not supplied

Reticuloendothelial system phagocytic activity in cirrhosis and its relation to bacterial infections and prognosis.

The reticuloendothelial system phagocytic activity, estimated by the plasma elimination rate constant of 99mtechnetium-sulfur colloid, was studied in 41 decompensated cirrhotics and 10 normal subjects. The results were related to the incidence and type of bacterial infections occurring during hospitalization and follow-up, and to survival. The elimination rate constant of 99mtechnetium-sulfur colloid was lower in cirrhotic patients (0.168 +/- 0.007) (means +/- S.E.) than in normal subjects (0.220 +/- 0.005) (p less than 0.01). Cirrhotics were divided into two groups. Group I (16 patients) and Group II (25 patients) had normal or reduced elimination rate constant of 99mtechnetium-sulfur colloid, respectively. Both groups were similar in relation to clinical and biochemical data, hepatic blood flow, and wedged hepatic venous pressure. However, the liver scan and the elimination rate constant of indocyanine green were more altered in Group II. Patients in Group II developed acute bacterial infections more frequently than did patients in Group I. During hospitalization (24 +/- 2 days), bacteremia occurred in six patients in Group II and in none in Group I (p less than 0.05). During follow-up (28 +/- 3 months), 5 patients in Group II and none in Group I developed bacteremia (p less than 0.05). The cumulative survival rate of Group I patients was higher (p less than 0.05) than that of Group II patients at 3 months (100 vs. 80%), 6 months (94 vs. 68%), 24 months (74 vs. 42%), and 48 months (68 vs. 34%). We suggest that decompensated cirrhotics with depressed reticuloendothelial system phagocytic activity are at great risk to acquire bacteremia, and that reticuloendothelial system phagocytic activity has prognostic value in cirrhosis.

Bacterial Infections↗
PubMedDate not supplied

Renal kallikrein excretion in cirrhotics with ascites: relationship to renal hemodynamics.

To investigate if the renal kallikrein-kinin system may be involved in the homeostasis of renal perfusion in cirrhosis, urinary kallikrein activity was measured in 11 normal subjects, 31 cirrhotics with ascites and preserved renal plasma flow (548.2 +/- 32.2 ml per min) and glomerular filtration rate (85.8 +/- 3.4 ml per min), and 18 cirrhotics with functional renal failure (renal plasma flow: 229.9 +/- 23.4 ml per min; glomerular filtration rate: 34.9 +/- 3.3 ml per min). Plasma renin activity, plasma norepinephrine concentration and the urinary excretion of prostaglandin E2 were also measured in these subjects. Cirrhotics without renal failure showed a significantly higher renin (4.9 +/- 1.1 ng per ml per hr), norepinephrine (458.2 +/- 50.4 pg per ml), urinary kallikrein (15.4 +/- 1.8 pkat per min) and urinary prostaglandin E2 (0.52 +/- 0.08 ng per min) than did normal subjects (1.08 +/- 0.1 ng per ml per hr, 218.1 +/- 18.2 pg per ml; 8.4 +/- 1.4 pkat per min and 0.24 +/- 0.02 ng per min, respectively). Cirrhotics with renal failure showed a significantly higher renin (16.1 +/- 3.4 ng per ml per hr) and norepinephrine (739.4 +/- 79.2 pg per ml), and a significantly lower urinary kallikrein (5.2 +/- 0.6 pkat per min) and urinary prostaglandin E2 (0.15 +/- 0.02 ng per min) than did normal subjects and cirrhotics without renal failure. Glomerular filtration rate correlated (p less than 0.001) with urinary kallikrein (r = 0.53), urinary prostaglandin E2 (r = 0.55), plasma renin (r = -0.41) and norepinephrine (r = -0.44).(ABSTRACT TRUNCATED AT 250 WORDS)

Aldosterone↗
PubMedDate not supplied

Temporal relationship between hyperaldosteronism, sodium retention and ascites formation in rats with experimental cirrhosis.

To investigate the role of aldosterone in sodium retention and ascites in cirrhosis, the urinary sodium excretion, sodium balance and urinary excretion of aldosterone-18-glucuronide (UAldV) were serially measured in 11 rats undergoing cirrhosis induction with carbon tetrachloride (CT) and phenobarbital (CT rats) and in 10 control rats which received phenobarbital. All CT rats developed ascites, seven within the ninth week after starting the program and four within the 10th week. One week before the onset of ascites, CT rats and control rats were different with respect to sodium excretion (1.41 +/- 0.15 vs. 1.82 +/- 0.1 mEq per day), sodium balance (0.57 +/- 0.12 vs. 0.20 +/- 0.09 mEq per day) and UAldV (67.8 +/- 9.5 vs. 25.7 +/- 1.7 ng per day). These differences were more pronounced within the week in which ascites was detected in CT rats. Before these 2 weeks, both groups did not differ with respect to these parameters. In the 132 urine samples obtained in CT rats, there was a correlation between sodium excretion and UAldV (r = -0.53; p less than 0.001). Twenty-one additional CT rats were divided into two groups. Eleven animals were given spironolactone (20 mg per day s.c. in olive oil) from the 6th week, and 10 only received olive oil. Thirteen weeks after starting the program, all rats not treated with spironolactone had sodium retention and ascites (in five rats, ascites appeared within the ninth week and in five within the tenth week); this occurred in only one animal treated with spironolactone.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldosterone↗
PubMedDate not supplied

Cefotaxime is more effective than is ampicillin-tobramycin in cirrhotics with severe infections.

We compared the effectiveness and incidence of nephrotoxicity of ampicillin-tobramycin and cefotaxime in 73 cirrhotics who had severe bacterial infection. Most of these patients had spontaneous peritonitis and/or bacteremia. Patients were randomly allocated into two groups. Group I included 36 patients treated with ampicillin-tobramycin and Group II comprised 37 patients treated with cefotaxime. Patients from both groups were similar with respect to clinical data, standard liver and renal function tests, types of infection and isolated organisms. Ninety-two per cent of bacteria isolated in Group I and 98% of those isolated in Group II were susceptible in vitro to ampicillin-tobramycin and to cefotaxime, respectively. Ampicillin-tobramycin cured the infection in 56% of Group I patients, and cefotaxime in 85% of Group II patients (p less than 0.02). Five patients treated with ampicillin-tobramycin, and none treated with cefotaxime developed superinfections (p = 0.024). Nephrotoxicity (impairment of renal function associated with an increase of urinary beta 2-microglobulin to over 2,000 micrograms per liter) occurred in two patients in Group I and none in Group II. These results suggest that broad-spectrum cephalosporins should be considered as first choice antibiotics in cirrhotic patients with severe infections.

Adult↗
PubMedDate not supplied

Oral, nonabsorbable antibiotics prevent infection in cirrhotics with gastrointestinal hemorrhage.

To investigate if oral, nonabsorbable antibiotics prevent bacterial infections in cirrhotics with gastrointestinal hemorrhage, 140 consecutive patients were randomly allocated into two groups: 68 patients (Group I) were given oral, non absorbable antibiotics (gentamicin + vancomycin + nystatin or neomycin + colistin + nystatin) from the inclusion into the trial up to 48 hr after cessation of the hemorrhage, or until emergency surgery or death in those cases who continued bleeding; and 72 patients (Group II) did not receive oral, nonabsorbable antibiotics. Both groups were similar in relation to clinical and laboratory data and characteristics of the hemorrhage. The incidence of infection was significantly lower in Group I than in Group II (11 patients in Group I and 25 in Group II developed proved infections; p less than 0.025). This difference was due to the fact that spontaneous bacteremia and peritonitis and urinary tract infection caused by enteric bacteria occurred almost exclusively in Group II. Two patients of Group I and 10 of Group II developed spontaneous bacteremia and/or peritonitis caused by enteric bacteria (p less than 0.025). These results indicate that prophylactic administration of oral, nonabsorbable antibiotics markedly reduces the incidence of infections caused by enteric bacteria in cirrhotic patients with gastrointestinal hemorrhage.

Administration, Oral↗
PubMedDate not supplied

Compensated cirrhosis: natural history and prognostic factors.

To investigate the natural history of compensated cirrhosis, 293 consecutive patients without previous major complications (ascites, jaundice, encephalopathy or gastrointestinal hemorrhage) were studied in terms of morbidity (probability of developing decompensated cirrhosis during follow-up) and survival. Patients were diagnosed by liver histology between 1968 and 1980. Median follow-up was 63 months. Decompensation of cirrhosis was considered when a patient first developed one of the major complications of the disease. Ten years after diagnosis, the probability of developing decompensated cirrhosis and the survival probability rate were 58 and 47%, respectively. A multivariate survival analysis (Cox's regression model) using clinical, biochemical and histological data obtained at diagnosis disclosed seven factors that predicted prognosis: serum bilirubin; serum gamma-globulin concentration; hepatic stigmata; prothrombin time; sex; age, and alkaline phosphatase. According to the contribution of each one of these factors to the final model, a prognostic index was constructed that allows calculation of the estimated survival probability. The predicting value of this index was validated by a split sample testing technique.

Adult↗
PubMedDate not supplied

Recurrence of spontaneous bacterial peritonitis in cirrhosis: frequency and predictive factors.

We investigated whether spontaneous bacterial peritonitis in cirrhosis is a recurrent process and attempted to identify possible predictors of recurrence in 75 consecutive cirrhotics who had recovered from a first episode of spontaneous bacterial peritonitis between January, 1981 and December, 1984 and who were followed closely throughout their illness (follow-up period 10 +/- 13 months; mean +/- S.D.). Thirty-eight patients (51%) developed one or more episodes of spontaneous bacterial peritonitis during follow-up, the probability of recurrence (Kaplan-Meier's method) being 43% at 6 months, 69% at 1 year and 74% at 2 years. Twenty-three variables (age, sex, etiology of cirrhosis, standard liver and renal function tests and characteristics of the first spontaneous bacterial peritonitis) were analyzed as possible predictors of recurrence of spontaneous bacterial peritonitis. In univariate analysis (curves of Kaplan-Meier compared with Mantel-Cox's method), serum bilirubin greater than 4 mg per dl, prothrombin less than or equal to 45% and protein concentration in ascitic fluid less than or equal to 1 gm per dl were significantly (p less than 0.05) associated with a high risk or recurrence of spontaneous bacterial peritonitis. In multivariate analysis (Cox multiple regression model), only ascitic fluid protein concentration (p = 0.005) and prothrombin activity (p = 0.009) were found to be independent predictors of recurrence of spontaneous bacterial peritonitis. Fifty-nine patients (79%) died during follow-up, 18 of them (31%) secondary to spontaneous bacterial peritonitis. The 1-year survival probability in the whole series of patients was 38%.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial Infections↗
PubMedDate not supplied

Atrial natriuretic factor in cirrhosis with ascites: plasma levels, cardiac release and splanchnic extraction.

The aim of this study was to determine the plasma levels, cardiac release and splanchnic extraction of atrial natriuretic factor in cirrhosis with ascites. The plasma concentration of immunoreactive atrial natriuretic factor in samples obtained from an antecubital vein was measured in 18 healthy volunteers and in 35 cirrhotics with ascites. In 11 of these cirrhotics and in 11 patients admitted to the hospital for the study of a thoracic pain who had no clinical or hemodynamic signs of cardiac failure (control group), the plasma levels of immunoreactive atrial natriuretic factor in samples from the coronary sinus, right atrium, pulmonary artery, hepatic vein and femoral vein were determined and the coronary sinus blood flow measured by thermodilution. Cirrhotic patients showed significantly higher plasma levels of immunoreactive atrial natriuretic factor in each vascular territory studied than did control subjects (coronary sinus: 101.2 +/- 10.6 vs. 26.1 +/- 4.7 fmoles per ml; right atrium: 32.5 +/- 5.8 vs. 9.4 +/- 3.5; pulmonary artery: 36.8 +/- 10.1 vs. 7.5 +/- 2.4; hepatic vein: 10.7 +/- 2.0 vs. 2.7 +/- 0.8; femoral vein: 18.2 +/- 2.4 vs. 3.1 +/- 0.9; antecubital vein: 14.7 +/- 1.6 vs. 4.0 +/- 0.8). The coronary sinus blood flow was also higher in cirrhotics (200 + 22 ml per min) than in controls (105 +/- 7 ml per min). Consequently, the estimated cardiac release and cardiac production of immunoreactive atrial natriuretic factor were strikingly increased in cirrhotics (13,334 +/- 2,007 and 5,484 +/- 1,734 fmoles per min, respectively) as compared to control subjects (1,669 +/- 338 and 1,431 +/- 350 fmoles per min, respectively; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Ascites↗
PubMedDate not supplied

Comparative study of aminoglycoside nephrotoxicity in normal rats and rats with experimental cirrhosis.

Several authors have suggested that the risk of developing aminoglycoside nephrotoxicity is greater in cirrhotic patients than in the noncirrhotic population. However, this has not been confirmed by other investigators. To compare the intensity and characteristics of aminoglycoside nephrotoxicity in cirrhotic and normal rats, 31 rats with carbon tetrachloride-induced cirrhosis with ascites and 35 control rats were treated with gentamicin. Each group of rats was divided into two subgroups in order to receive 10 or 40 mg per kg per day of gentamicin, and different subsets of animals were killed on Days 4, 8 and 12 of treatment for renal histological examination and determination of renal tissue gentamicin concentration. Urine volume, osmolality, sodium excretion and N-acetyl-beta-D-glucosaminidase activity were measured daily throughout the study. Creatinine clearance and trough plasma concentration of gentamicin were determined in each animal immediately before killing. There were no significant differences between cirrhotic and control rats in relation to the magnitude of changes in urine volume, osmolality, sodium excretion and N-acetyl-beta-D-glucosaminidase activity and creatinine clearance during gentamicin administration. The values of a histopathological score semiquantitatively assessing the renal morphological changes observed by light microscopy were not significantly different in cirrhotic and control rats. In addition, similar trough plasma and renal cortical tissue concentrations of gentamicin were observed in both groups of animals. These results suggest that, in this experimental model, cirrhosis does not increase the risk for aminoglycoside nephrotoxicity.

Acetylglucosaminidase↗
PubMedDate not supplied

Peripheral arterial vasodilation hypothesis: a proposal for the initiation of renal sodium and water retention in cirrhosis.

Renal sodium and water retention and plasma volume expansion have been shown to precede ascites formation in experimental cirrhosis. The classical "underfilling" theory, in which ascites formation causes hypovolemia and initiates secondary renal sodium and water retention, thus seems unlikely. While the occurrence of primary renal sodium and water retention and plasma volume expansion prior to ascites formation favors the "overflow" hypothesis, the stimulation of the renin-angiotensin-aldosterone system, vasopressin release and sympathetic nervous system associated with cirrhosis is not consonant with primary volume expansion. In this present article, the "Peripheral Arterial Vasodilation Hypothesis" is proposed as the initiator of sodium and water retention in cirrhosis. Peripheral arterial vasodilation is one of the earliest observations in the cirrhotic patient and experimental animals with cirrhosis. Arterial vasodilators and arteriovenous fistula are other examples in which renal sodium and water retention occur secondary to a decreased filling of the arterial vascular tree. An increase in cardiac output and hormonal stimulation are common features of cirrhosis, arteriovenous fistula and drug-induced peripheral arterial vasodilation. However, a predilection for the retained sodium and water to transudate into the abdominal cavity occurs with cirrhosis because of the presence of portal hypertension. The Peripheral Arterial Vasodilation Hypothesis also explains the continuum from compensated to decompensated cirrhosis to the hepatorenal syndrome.

Animals↗
PubMedDate not supplied

Experience with cefotaxime in the treatment of spontaneous bacterial peritonitis in cirrhosis.

Spontaneous bacterial peritonitis (SBP) is a severe infectious complication in cirrhotic patients, and initial antibiotic therapy must be empirical. An initial study published in 1985 found that cefotaxime administered at a dose of 2 g every 4 h was more effective and safer than the combination of tobramycin-ampicillin. Since then, cefotaxime has been considered the agent of choice in the empiric therapy of SBP. Subsequent publications showed that a dosage of 2 g every 6 h was also adequate in this infection. More recent studies have demonstrated that the high efficacy of cefotaxime in SBP can be maintained by using lower dosages than those used in initial investigations. In one of these studies, a dose of 2 g every 8 h for 5 days was found to be as effective as the same dose for 10 days. Finally, a prospective, randomized multicenter trial aimed at comparing the efficacy of two different dosages of cefotaxime, 2 g every 6 h versus 2 g every 12 in a large series of cirrhotic patients with SBP, showed that both dosages resulted in similar rates of resolution of infection and survival. Despite the reasonably adequate rate of infection resolution in SBP patients, the in-hospital mortality rate remains high as a result of complications such as renal failure. Further studies should therefore be addressed to reducing the incidence of these complications and thus improving survival.

Bacterial Infections↗