Risk of hyperamylasemia and acute pancreatitis after double-balloon enteroscopy: a prospective study.

BACKGROUND AND STUDY AIMS: There have been reports, mainly retrospective, of pancreatitis and hyperamylasemia after anterograde double-balloon enteroscopy (DBE). Our aim was to report the incidence of pancreatitis and hyperamylasemia after DBE and investigate possible risk factors associated with its occurrence. PATIENTS AND METHODS: In this single-center prospective cohort study, serum samples were taken for amylase and lipase before and 3 hours after anterograde DBE in consecutive patients. Multiple variables were recorded, including total procedure time, insertion depth, and number of passes. Patients were evaluated to 24 hours later for signs of pancreatitis. The main outcome measures were the occurrence of hyperamylasemia and pancreatitis. RESULTS: 92 patients were included in the analysis (58 women, 34 men; mean age 54 years, range 18-89). The mean total procedure time was 62 minutes (range 30-120). The mean post-procedure amylase and lipase levels were significantly higher in comparison with the baseline levels (165 U/L vs. 69 U/L and 144 U/L vs. 28 U/L respectively, P<.05); 36 patients (39%) showed hyperamylasemia after the procedure and three patients developed acute mild pancreatitis. Hyperamylasemia was associated more frequently with procedure duration greater than 60 minutes ( P<.001) and insertion depth greater than 25 cm ( P<.013). CONCLUSIONS: The incidence of hyperamylasemia after anterograde DBE is common and particularly associated with longer procedure time and insertion depth. The cumulative incidence of pancreatitis was 3%. We recommend the avoidance of both unnecessarily lengthy procedures and deep insertion distances in patients who undergo anterograde DBE.

Capsaicin induction of esophageal symptoms in different phenotypes of gastroesophageal reflux disease.

BACKGROUND: Type 1 vanilloid receptors (TRPV1) have been described on esophageal afferent sensitive neurons. Stimulation of TRPV1 receptors with capsaicin may induce heartburn. Capsaicin is the pungent component of chili and the most extensively studied TRPV1 agonist. OBJECTIVES: To investigate the effect of esophageal stimulation with intraesophageal capsaicin administration on induction of esophageal symptoms and on esophageal chemo-sensitization to acid in different gastroesophageal reflux disease (GERD) phenotypes. METHODS: Healthy volunteers and patients with GERD (non-erosive [NERD], erosive GERD [EE] and Barrett's esophagus [BE]) were prospectively studied. All subjects were randomized to receive either intraesophageal perfusion capsaicin or saline 0.9%. Thirty minutes after saline or capsaicin infusion an acid perfusion test of HCl was performed. A week later, a crossover phase with capsaicin versus saline was performed. Five symptoms were evaluated every 5 min during the first 30 minutes after capsaicin, saline, and acid perfusion: chest burning, chest pain, heartburn, epigastric burning, and epigastric pain. RESULTS: 17 healthy subjects and 31 GERD patients (10 NERD, 11 EE, and 10 BE) were included. Twenty- eight (90%) of GERD and 6 (35%) of healthy subjects had esophageal symptoms after capsaicin perfusion. Mean for the 5 evaluated symptoms induced by capsaicin was significantly higher in the GERD group compared to the control group. The highest symptom severity was in the erosive subgroup. Capsaicin decreased the 5 symptoms induced by acid perfusion in both healthy volunteers and GERD patients. Total score of esophageal symptom severity (produced by acid perfusion) was significantly reduced by capsaicin infusion in the BE group. CONCLUSIONS: Capsaicin induces esophageal and gastric symptoms in healthy volunteers and GERD patients. Capsaicin reduces esophageal chemosensitivity to acid, especially in patients with BE.

Effect of pentoxifylline on levels of pro-inflammatory cytokines during chronic hepatitis C.

The cellular and humoral natural immune response induced by hepatitis C virus (HCV) is commonly unable to eradicate the virus. HCV is a highly mutable, hepatotropic RNA virus that causes acute and chronic hepatitis, an infection that involves the production of various cytokines. The aim of the study is to analyse the expression of pro-inflammatory cytokines IL-1beta, TNF-alpha, IFN-gamma and the chemokine CXCL8 (IL-8) in liver tissue and their expression and secretion in PBMC of patients with chronic hepatitis C (CHC), in response to pentoxyfilline (PTX). We studied six CHC patients, naive to treatment. Patients received PTX 400 mg twice a day/8 weeks. Pentoxyfilline resulted in decreased expression of mRNA of liver IL-1beta, TNF-alpha and IFN-gamma: 144.2 versus 83.5 molecules of IL-1beta (P < 0.05), TNF-alpha 194.3 versus 17.6 molecules (P = 0.03) and IFN-gamma 26.1 versus 0.5 molecules (P = 0.04). Following PTX, PBMC exhibited a decrease in IFN-gamma mRNA 12.2 versus 1.5 molecules (P = 0.028) and CXCL8 4.2 versus 2.5 molecules (P = 0.027). In PBMC, only the secretion of TNF-alpha was decreased 1109 versus 933.5 pg/ml, P = 0.046. Production of cytokines both locally (within the liver) and systemically (PBMC) may serve as biomarkers of the infection with hepatitis C. PTX inhibits the expression of several pro-inflammatory cytokines in the liver. These results indicate that it is worth exploring PTX in hepatitis in future clinical trials in nonresponders to antiviral treatment.

Histologic diagnosis of primary hyperparathyroidism: a concordance analysis between three pathologists.

Primary hyperparathyroidism (HPT) is caused by a parathyroid adenoma, hyperplasia or carcinoma. Difficulties for the histologic diagnosis of abnormal parathyroid tissue are widely recognized. The aim of the study was to evaluate the reproducibility of the morphologic criteria through a concordance study among three pathologists. Representative slides of 40 patients with biochemically primary HPT stained with hematoxylin and eosin were blindly reviewed by three pathologists. Each pathologist established the diagnosis of adenoma or hyperplasia and assessed the presence of fat cells, a rim of normal tissue, a fibrous capsule, the number of cellular types, the lobular pattern, and the characteristics of the blood vessel's wall. A concordance analysis was then performed. Mean age of the group was 55 +/- 14 yr, 7 were males and 33 females. The concordance analysis among the three pathologists for the differential diagnosis between adenoma and hyperplasia, showed a Kappa index of 0.5. Kappa index for the presence of fat cells was 0.56, for the presence of a rim of normal tissue 0.47, and for the number of cellular types 0.29. The concordance for the differential diagnosis between parathyroid adenoma and hyperplasia in this study was low.

Effect of endotoxin pretreatment on hepatic stellate cell response to ethanol and acetaldehyde.

BACKGROUND AND AIM: The role of endotoxin in alcohol-induced liver damage is well recognized. How pre-exposure to endotoxin might affect alcohol injury is not known. We herein studied the effect of endotoxin pretreatment on hepatic stellate cell (HSC) response to ethanol and acetaldehyde. METHODS: Rat HSC (CFSC-2G) were exposed to media supplemented with 1 microg/mL lipopolysaccharide (LPS). This was followed by a 24 h exposure to media containing LPS plus 50 mmol/L ethanol or 175 micromol/L acetaldehyde. Lipid peroxidation, collagen, and tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6 and transforming growth factor (TGF)-beta1 secretion were determined at the end of both periods of exposure. RESULTS: Lipopolysaccharide pretreatment did not modify lipid peroxidation induced by ethanol or acetaldehyde alone. Glutathione (GSH) content decreased to 4.2 +/- 0.5 and 16.3 +/- 0.8 nmol protein after exposure to ethanol or acetaldehyde alone, and decreased further with LPS pretreatment (2.4 +/- 0.2 and 2.7 +/- 0.3 nmol/mg protein, respectively). Oxidized GSH (GSSG) content increased in ethanol and acetaldehyde LPS-pretreated cells only. Collagen secretion increased to 988 +/- 82 and 1169 +/- 91 microg/10(6) cells after exposure to acetaldehyde or LPS alone. Lipopolysaccharide pretreatment enhanced collagen secretion significantly in both ethanol- and acetaldehyde-treated cells (969 +/- 56 and 1360 +/- 72 microg/10(6) cells, respectively). Interleukin-6 production increased to 288 +/- 48, 1195 +/- 86 and 247 +/- 35 pg/mL per 10(6) cells after ethanol, acetaldehyde and LPS exposure, and increased further with LPS pretreatment in ethanol-exposed cells (680 +/- 23 pg/mL 10(6) cells). CONCLUSION: Lipopolysaccharide pretreatment of HSC adds to the damage produced by ethanol and acetaldehyde by diminishing GSH content and increasing GSSG content, collagen and IL-6 secretion.

Asymptomatic gallstones and duration of cyclosporine use in kidney transplant recipients.

BACKGROUND: Cyclosporine (CsA) use has been associated to the development of cholelithiasis in transplant recipients. We herein explored the role of time under CsA on this association in asymptomatic adult kidney transplant recipients (KTR). METHODS: A cross-sectional study was conducted in 140 KTR with variable post-transplant follow-up (PTFU), and without history of symptomatic biliary disease. Upper abdominal ultrasound was performed in all patients. According to the immunosuppressive schedule, patients were classified in three groups: Azathioprine + prednisone (group 1, n = 37), azathioprine + prednisone < 24 months CsA (group 2, n = 58), or azathioprine + prednisone > or = 24 months CsA (group 3, n = 45). Age at time of ultrasound performance, gender, PTFU, chronic viral liver disease, parity, oral contraceptives, serum lipids, diabetes and body mass index were analyzed concomitantly. RESULTS: Median age was 38, 31, and 36 years in groups 1, 2, and 3, respectively. The male:female ratio in the same groups was 1.5:1, 1:1, and 2:1. Mean PTFU was 130, 48, and 53 months, respectively (p = 0.0001). Gallstones were found in three (8%) group 1 KTR, in nine (16%) group 2 KTR, and in 10 (22%) group 3 KTR (p = 0.214). Adjusting for PTFU, the association between length of CsA and prevalence of lithiasis was significantly stronger among those with longer use of CsA (odds ratio = 6.1, p = 0.046). No significant differences were found among groups in the other variables. CONCLUSIONS: KTR receiving CsA for more than two years show increased prevalence of gallstones.

Potential harmful effect of iodinated intravenous contrast medium on the clinical course of mild acute pancreatitis.

HYPOTHESIS: A worse clinical outcome might be expected in patients with acute pancreatitis (AP) who receive intravenous contrast medium for a nondynamic contrast-enhanced computed tomographic (CECT) study early during hospital admission. DESIGN: Cohort analytic study. SETTING: Tertiary care center. PATIENTS: Of 126 patients with mild AP, 52 patients underwent CECT to establish AP diagnosis (group 1), and the remaining 74 did not (group 2). MAIN OUTCOME MEASURES: Survival and development of local or systemic complications during the hospital stay. Potential confounders were demographic, clinical, and biochemical data, as well as therapeutic measures. The Atlanta classification was used to define local and systemic complications. RESULTS: Mean age, etiology of AP, prognostic score on admission, and pharmacologic treatment were similar between groups. Local and systemic complications were more frequently observed in patients who underwent CECT (odds ratio, 11.4; 95% confidence interval, 2.0-64.8; P =.008). Six patients, all in group 1, developed a pancreatic abscess (odds ratio, 20.8; P =.004). In 5 of them, a second CECT showed more severe AP changes. The association between CECT and abscess development was more apparent in patients with a body mass index of 25 or more and/or nasogastric suction. Six patients in group 1 and 1 in group 2 had systemic complications (odds ratio, 9. 5; P =.01). There were no deaths. CONCLUSIONS: The observed increased incidence of local and systemic complications in patients with mild AP who undergo CECT, particularly in those with a body mass index of 25 or more, suggests a potentially harmful effect of intravenous contrast medium. Until this issue is clarified, it seems reasonable to restrict the use of dynamic CECT to patients with severe AP, protracted clinical course, or suspected local septic complication.

Preservation of a digital osteotendinous structure with an omental flap.

Taking into account the angiogenic properties of the omentum to revascularize ischemic tissues, this experimental, longitudinal, prospective, double-blind study in rabbits was designed to revascularize and preserve the mobility of a digital osteotendinous structure surgically devascularized in advance and to compare such omental angiogenic ability with that of the muscle and the panniculus carnosus. Thirty New Zealand rabbits were used. Three toes from the hind feet were surgically amputated from each rabbit. The skin was removed, exposing the bones, tendons, ligaments, and joints, to form what we termed the osteotendinous structure. Through a median laparotomy, the first part of each rabbit's own osteotendinous structure was placed inside the panniculus carnosus (group I), the second under the rectus abdominis muscle (group II), and the third was wrapped in a pediculate omental flap (group III). Three weeks later, each structure was assessed clinically for mobility and fibrosis and microscopically for fibrosis, newly formed vessels, viability, and tissue regeneration. Clinically, the group I structures showed a greater amount of fibrosis. The structures in groups II and III showed minimal fibrosis in all but four cases, which showed moderate fibrosis. Differences in joint mobility were assessed with the Kruskal-Wallis test. There was a statistically significant difference in mobility for the structures from group III, which was higher, followed by those from groups II and I. The exception was the proximal interphalangeal joints in groups II and III, for which the differences had no statistical significance. Microscopically, fibrosis and tissue necrosis were intense in the structures in group I, moderate in the group II structures, and mild in the group III structures. Conversely, vessel neoformation and tissue regeneration were intense in the structures in group III, moderate in group II, and were nil in group I. This study confirms with statistical significance that, in the rabbit, the omentum has a higher ability to revascularize degloved tissues than do the muscle and the panniculus carnosus, thus preserving a higher joint and tendon mobility. Consequently, it is suggested that a free omental flap be used in the treatment of ring avulsion injuries that lead to degloving of the digits.

Serum erythropoietin levels in kidney donors after renal transplantation.

BACKGROUND: Renal transplantation is the treatment of choice for many patients with end-stage renal disease. In the donor, renal excretory function is not affected after nephrectomy; however, little is known about other functions such as erythropoietin production. We studied the erythropoietin production in renal donors after nephrectomy. METHODS: We included healthy individuals fulfilling the criteria for kidney donation. Blood samples were collected before and monthly from 1 to 6 months after nephrectomy. Complete blood cell counts and erythropoietin were assayed. RESULTS: Eight kidney donors were studied. A significant increase in erythropoietin levels was observed during the first 3 months, but no difference was observed by the 4th month as compared with basal values. CONCLUSIONS: Erythropoietin production rose during the first 3 months after nephrectomy. However, erythropoietin was normal by the 4th month. Unchanged hemoglobin levels may suggest that the compensatory production of erythropoietin could participate in the preservation of an adequate physiological status of the donor after nephrectomy.

Comparison of ceftibuten vs. amoxicillin/clavulanic acid as antibiotic prophylaxis in cholecystectomy and/or biliary tract surgery.

A randomized, comparative, prospective clinical trial was carried out at a tertiary care center to compare the efficacy of two antibiotic regimens in the prophylaxis of postoperative infection in patients undergoing biliary tract surgery. One hundred patients undergoing cholecystectomy or biliary tract exploration were randomly allocated to one of the following antibiotic regimens: the standard regimen of three doses of amoxicillin/clavulanic acid (1000/200 mg) given by intravenous infusion, or a single dose of ceftibuten (400 mg) given orally. Patients were monitored during their stay in the hospital and over a 2 week period as outpatients. Fifty adult patients were included in each group. Mean age was 49 years, and sex distribution was 82 women and 18 men. The groups were comparable in terms of demographic characteristics and comorbidity. There were no cases of postoperative infection in the ceftibuten group, but five cases of infection occurred in the amoxicillin/clavulanic acid group (P < 0.05). No adverse effects were observed with either antibiotic. The treatment cost per patient was significantly lower for ceftibuten. The results indicate that ceftibuten is well tolerated and more effective than amoxicillin/clavulanic acid for prophylaxis following gallbladder and biliary tract surgery. In addition, ceftibuten has the advantage of being more cost-effective and easier to administer than amoxicillin/clavulanic acid so it could be considered as an alternative for antibiotic prophylaxis in these types of surgical procedures.

Cytokines, growth factors, and oxidative stress in HepG2 cells treated with ethanol, acetaldehyde, and LPS.

Inflammatory mediators, including cytokines, growth factors, and reactive oxygen species, are associated with the pathology of chronic liver disease. In the liver, cytokine and growth factor secretion are usually associated with nonparenchymal cells, particularly Kupffer cells. In the present studies, the effect of 24 and 72 h administration of ethanol (50 mM). acetaldehyde (175 microM), and LPS (1 microg/ml) were studied on the expression and secretion of TNF-alpha, IL-1beta, IL-6, and TGF-beta3, lipid peroxidation damage and glutathion content in HepG2 cell cultures. A 24 h exposure to ethanol induced the expression of TNF-alpha and TGF-beta1, and the secretion of IL-1beta and TGF-beta1. With the same period of treatment, acetaldehyde markedly increased TNF-alpha expression, and stimulated IL-1beta secretion, while LPS exposure induced the expression of TNF-alpha, IL-6, and TGF-beta1, and the secretion of IL-1beta, IL-6, and TGF-beta1. A reduced in TNF-alpha response and TGF-beta1 expression were observed after 72 h exposure to ethanol. A 72 h acetaldehyde exposure decreased markedly TNF-alpha expression and stimulated a previously absent TGF-beta1 response. With the same time of exposure, LPS reduced slightly TGF-beta1 expression, and decreased its secretion. IL-1beta and IL-6 were not detected under 72 h exposure conditions. Lipid peroxidation damage was increased in all treatments, but higher values were found in 72 h treatments. Glutathion content diminished in all treatments. These findings suggest that HepG2 cells, independent of other cells such as Kupffer or macrophages, participate in a differential cytokine, growth factor and oxidative stress response, which differs according to the toxic agent and the time of exposure.

Refractory anemia with excess of blasts: increased survival when treated with cyclophosphamide, methotrexate and 6-mercaptopurine.

Owing to the lack of efficacious treatments for refractory anemia with an excess of blasts (RAEB), evaluation of other therapeutic strategies is necessary, especially in elderly patients. We report herein our experience with an oral triple drug regimen with cyclophosphamide 200 mg/m2 and methotrexate 20 mg/m2 once a week, and 6-mercaptopurine 50 mg/m2 daily for the treatment of RAEB. Eighteen patients with a median age of 62 yr (range 17-80) received a triple drug regimen (TDR), and they were compared with 6 patients who received oxymetholone (2 mg/m2/d) and 9 who received supportive therapy only. Partial response was achieved in 45% of patients receiving TDR. In 77% of patients treated with TDR the number of bone marrow blasts decreased to <5%; however, they persisted with trilineage dyspoietic morphologic changes. Median survival for TDR was 23 months (range 1-96), which was longer than that for the other groups. A slight rise in liver enzymes was the only side effect of TDR. TDR seems to be a useful alternative in patients with RAEB, a finding to be confirmed in further prospective studies.

[Prospective evaluation of gastroesophageal reflux in patients with achalasia treated with pneumatic dilatation, thoracic or abdominal myotomy]. / Evaluación prospectiva de reflujo gastroesofágico en pacientes con acalasia tratados con dilatación neumática, miotomía torácica o abdominal.

INTRODUCTION: Symptomatic gastroesophageal reflux (GER) occurs in 0-20% of patients treated with pneumatic dilation and in 5-30% with cardiomyotomy. However, the prevalence of GER evaluated with esophageal pH-monitoring is unknown. AIM: To investigate the frequency of GER in achalasia patients treated with pneumatic dilation or myotomy. MATERIAL AND METHODS: Patients with achalasia were evaluated prospectively and classified in 4 groups: group A = treated with pneumatic dilation; group B = treated with open abdominal myotomy; group C = transthoracic myotomy; and group D = submitted to laparoscopic abdominal myotomy with antireflux procedure. Esophageal manometry and 24 h pH-monitoring were performed in all patients. GER was defined as a pH < 4 in more than 4% of the total time. RESULTS: Thirty-one patients, 22 women and 9 men, with a mean age of 44.7 years were evaluated. Nine patients had GER symptoms and 22 were asymptomatic. GER was detected with pH-metry in 42% of the total group: 33% for group A, 75% for group B, 44% for group C and none for group D. CONCLUSIONS: Prevalence of GER in achalasia patients treated with pneumatic dilation and surgical myotomy was high. We suggest the inclusion of 24 hr esophageal pH-metry in the follow-up due to the significant prevalence of asymptomatic GER. Minimal hiatus dissection and antireflux procedure were surgical factors related with a lower frequency of GER after achalasia myotomy.

Laparoscopic versus open splenectomy for immune thrombocytopenic purpura.

BACKGROUND: Laparoscopic splenectomy (LS) has been proposed as a substitute to open splenectomy (OS) in the treatment of immune thrombocytopenic purpura (ITP). The aim of this study was to compare two cohorts of patients with ITP who underwent OS or LS. PATIENTS AND METHODS: From February 1990 to January 1997, 27 patients underwent OS and 22 LS. Perioperative characteristics, outcomes, and complications were comparatively analyzed. RESULTS: Mean age was 38 years (+/- 16) in the OS group, and 39 (+/- 16) in the LS group; the male: female ratio was 1:2 in both groups. Median preoperative platelet count was 16 x 10(9)/L (range 2 to 186 x 10(9)/L) in the OS group, and 50 x 10(9)/L (2 to 241 x 10(9)/L) in the LS group. Mean operative time was 2.7 hours (+/- 0.7) for OS, and 4.5 hours (+/- 1) for LS (P <0.0001). Two conversions to laparotomy occurred in the LS group. A total of 14 complications occurred in 10 patients of the OS group; 8 complications occurred in 6 patients of the LS group. Two patients died in the OS group and 1 in the LS group. Mean postoperative discharge was 6 days (3 to 44) in the OS group and 4 days (2 to 11) in the LS group (P <0.02). Response rates were similar in both groups. CONCLUSIONS: Laparoscopic splenectomy is comparable to OS in terms of efficacy and safety, and it is associated with a shorter hospital stay.

[Identification of the patient with acute severe pancreatitis. A prospective, comparative study of the Ranson and the Salvador Zubirán National Institute of Nutrition criteria]. / La identificación del enfermo con pancreatitis aguda grave. Un estudio prospectivo, comparativo entre los criterios de Ranson y los del Instituto Nacional de la Nutrición Salvador Zubirán.

Early detection of severe acute pancreatitis could represent a formidable task for the clinician with limited resources. We have previously proposed a series of parameters that can identify patients with severe acute pancreatitis. The aim of this prospective study was to compare Ranson criteria with those previously described by the authors (INNSZ criteria) in 78 patients with acute pancreatitis. Sensitivity, specificity, positive and negative predictive values and accuracy were similar in both scores. We found a good correlation (r = 0.65, p < 0.001) and agreement (z = 5.0, Kappa 0.69, p < 0.001) between Ranson and INNSZ criteria. Our results allow us to propose INNSZ severity criteria as an easy and inexpensive alternative in the evaluation of patients with acute pancreatitis.

Hemophagocytic syndrome associated with hematological neoplasias.

Hemophagocytic syndrome (HPS) is a reactive process that complicates several diseases including hematological neoplasias (HN). It has been suggested that HPS may be a negative prognosis factor for neoplastic diseases. In this retrospective analysis, 13 cases with HPS associated to HN were compared with two age, sex, diagnosis, disease stage and treatment matched controls in order to determine the impact of this syndrome on the survival. Cases with HPS were adult patients with a male:female ratio of 1:1 and their clinical picture was characterized by fever, lymphadenopathy, hepatosplenomegaly, and pancytopenia. Median survival since HN diagnosis was 7 and 48 months for the HPS and control groups, respectively (P = 0.0001). In ten patients who died, median survival after HPS presentation was 1 month. These results suggest that the presence of HPS is a negative prognosis factor in patients with HN. Due to its high mortality rate, an individualized, early, and intensive chemotherapeutic regimen may be required for HN complicated with this syndrome.

Cardiac abnormalities associated with morbid obesity.

Morbidly obese patients are at increased risk for structural and functional abnormalities of the heart. This paper summarizes the effects of obesity on the heart, the effect of weight reduction on cardiac function, the impact of coronary artery disease on cardiac cardiomyopathy, and our experience in obesity heart disease at the Instituto Nacional de la Nutrición in Mexico.

Obesity: a risk factor for severe acute biliary and alcoholic pancreatitis.

OBJECTIVE: In this study we evaluate the association between obesity and complication development in patients with a first-attack acute pancreatitis (AP), and investigate the influence of comorbid factors on this association. METHODS: Medical records of 150 patients with AP were reviewed. General data, AP etiology, admission AP prognostic criteria, and occurrence of complications were recorded. Patients were classified according to body mass index (BMI) as obese (BMI > 25 kg/m2) and nonobese (BMI < or = 25 kg/m2). RESULTS: Prevalence of obesity was 57%. Thirty-eight percent of the obese patients developed complications as compared with 21% of the nonobese (RR=1.74; 95% CI, 1-2.9). The risk for severe AP increased according to the degree of obesity. Pancreatic and peripancreatic necrosis was more common in obese patients (17.6% vs 6%), as was the incidence of infectious complications. The risk for severe AP was highest in obese patients with either alcoholic (RR=5.3; 95% CI, 1.2-23) or biliary etiology (RR=5.2, 95% CI, 1-26). CONCLUSION: Obesity may predispose to a complicated course of AP, especially if it is secondary to alcohol or gallstones. Further studies are needed to establish the precise prognostic value of obesity in AP, as well as the pathogenic mechanisms involved in the process.

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.

Effect of the menstrual cycle in ethanol pharmacokinetics.

Differences in ethanol pharmacokinetics within the menstrual cycle have previously been reported and attributed to variations in body composition, hormonal influences and gastric emptying. To establish the role of the menstrual cycle in ethanol pharmacokinetics associated with changes in body composition, ethanol blood concentrations were measured in nine healthy women during the midfollicular (P1, days 8-10) and midluteal (P2, days 22-24) phases of the menstrual cycle after a postprandial oral ethanol dose (0.3 g kg(-1)). Total body water was assessed by dual-energy x-ray densitometry (DEXA) on both occasions. Median total body water did not vary during either phase of the menstrual cycle (P1 = 54.54%, P2 = 54.66%; P = 0.9296). Median area under the ethanol concentration-time curve (AUC) was lower during P1 (215.33 mg.h dl(-1)) than during P2 (231.33 mg.h dl(-1))(P = 0.8253). No significant differences were found on ethanol pharmacokinetics in either phase of the menstrual cycle.