Search

Up to 30% of patients with celiac disease (CD) suffer from concurrent autoimmune disease, compared to 3% of the general population. The association between CD and the current clinical phenotypes of inflammatory myopathies (IIM) patients has not been thoroughly addressed. Assess the CD features among patients with IIM and their relationship with the clinical phenotype and the myositis specific (MSA) and associated antibodies (MAA). For this cross-sectional study, we recruited 99 adult patients classified as IIM from a tertiary center in Mexico. We assessed serum MSA, MAA, and CD-associated autoantibodies (IgA anti-tissue transglutaminase (tTG) and both IgA and IgG anti-deaminated gliadin peptide (DGP)). Patients with highly suggestive serology for CD were then tested for IgG anti-endomysium antibodies, and a duodenal biopsy was performed. 70.7% of patients were positive for at least one antibody. Nine duodenal biopsies were taken, revealing findings compatible with celiac disease in two cases. Subjects with anti-MDA5 antibodies were more likely to have positive anti-tTG IgA antibodies (OR 6.76, 95% CI 1.85-24.62, P = 0.013) and suggestive CD serology (OR 6.41, 95% CI 1.62-25.29, P = 0.009). Patients with anti-Mi2 antibodies were more likely to have positive anti-DGP IgG antibodies (OR 3.35, 95% CI 1.12-9.96, P = 0.039), while positivity for these autoantibodies was less frequent in patients with anti-NXP2 antibodies (OR 0.22, 95% CI 0.06-0.80, P = 0.035). There is a higher prevalence of serologic and definite CD in patients with IIM compared to the general population. Identifying this subgroup of patients may have prognostic and therapeutic implications. Key points • The study estimated a serological celiac disease (CD) prevalence of 70.7% in patients with idiopathic inflammatory myopathies (IIM) and a biopsy-confirmed prevalence of 2%, suggesting that IIM patients should be considered a high-risk population for CD. • We identified a significant association between serological CD and the presence of anti-MDA5 and anti-Mi2 antibodies, suggesting a potential justification for celiac disease screening in this specific subgroup of patients. • The impact of gluten-free diets on IIM patients with serological markers of CD remains untested and warrants further investigation through prospective, randomized studies., (© 2024. The Author(s), under exclusive licence to International League of Associations for Rheumatology (ILAR).)

Objectives: Endoscopic ultrasound-guided tissue acquisition (EUS-TA) has been the most common method used for the preoperative cytopathological diagnosis of solid tumors of the pancreas. There are only a few reported cases about the role of endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) in the pre-operative diagnosis of solid pseudopapillary neoplasms (SPN). This study aimed to evaluate the diagnostic yield of EUS-TA,including endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) andEUS-FNB, in patients with SPN., Methods: We performed a retrospective analysis of patients with EUS-TA for SPN diagnosis in 2 referral centers. The primary outcome was the diagnostic yield of EUS-TA compared to the surgical specimen., Results: Seventy-four patients with SPN of the pancreas were identified. Eighteen had a EUS-TA (10 EUS-FNB and 8 EUS-FNA). The median age of the patients was 31 years (IQR 21-38), and all patients were women. The most common presenting symptom was abdominal pain. Most of the tumors were in the head of the pancreas (9/18; 50%). The median tumor size by EUS was 4.5 cm (min-max 2-15 cm). The most common appearance on EUS was a solid lesion ( n  = 8/18, 44.4%). A definitive presurgical cytopathological diagnosis was obtained in 16/18 patients (88.8%) with EUS-TA. The sensitivity and positive predictive value of the EUS-TA were 94% each. One patient in the EUS-FNB group developed mild acute pancreatitis., Conclusion: The diagnostic yield of the EUS-TA in SPN is high. In most cases, the diagnosis was obtained with the first procedure. No differences in the diagnostic yield or AEs between EUS-FNA vs. EUS-FNB needles were seen.

Background: The safety and efficacy data of the different types of available vaccines is still needed. The goal of the present analysis was to evaluate the humoral response to the COVID-19 vaccines in orthotopic liver transplant (OLT) recipients., Methods: Participants were included from February to September 2021. No prioritized vaccination roll call applied for OLT patients. Controls were otherwise healthy people. Blood samples were drawn after 15 days of the complete vaccine doses. The samples were analyzed according to the manufacturer's instructions using the Liaison XL platform from DiaSorin (DiaSorin S.p.A., Italy), and SARS-COV-2 IgG II Quant (Abbott Diagnostics, IL, USA)., Results: A total of 187 participants (133 OLT, 54 controls, median age: 60 years, 58.8% women) were included for the analysis; 74.3% had at least one comorbidity. The serologic response in OLT patients was lower than in controls (median 549 AU/mL vs. 3450 AU/mL, respectively; p = 0.001). A positive humoral response was found in 133 OLT individuals: 89.2% with BNT162b2 (Pfizer-BioNTech), 60% ChAdOx1 nCOV-19 (Oxford-AstraZeneca), 76.9% with CoronaVac (Sinovac, Life Sciences, China), 55.6% Ad5-nCov (Cansino, Biologics), 68.2% Gam-COVID-Vac (Sputnik V) and 100% with mRNA-1273. In controls the serological response was 100%, except for Cansino (75%). In a multivariable model, personal history of COVID-19 and BNT162b2 inoculation were associated with the serologic response, while the use of prednisone (vs. other immunosuppressants) reduced this response., Conclusion: The serologic response to COVID-19 vaccines in OLT patients is lower than in healthy controls. The BNT162b2 vaccine was associated with a higher serologic response., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Lactose intolerance is a condition with an elevated prevalence worldwide, especially in Latin American, Asian, and African countries. The aim of the present narrative review was to highlight the importance of accurately diagnosing lactose intolerance to prevent self-diagnosis that results in the unnecessary elimination of milk and dairy products from the diet and the consequent deprivation of nutrients that could be essential at certain stages of life. The pathophysiologic mechanism of deficient lactose absorption in the intestine can be primary, secondary to other enteropathies, or coexistent with other intestinal diseases with similar symptoms, such as irritable bowel syndrome, bacterial overgrowth syndrome, or celiac disease, causing confusion in relation to diagnosis and treatment. Lactose intolerance consists of a set of symptoms attributed to the consumption of milk and dairy products that are assumed to be due to deficient digestion of that disaccharide. A wide range of tests have been validated to detect deficient digestion that include blood tests, genetic mutation analyses, breath tests, and recently, a urine test, all of which are described in the present article. Nevertheless, there are few validated questionnaires for symptom evaluation and measurement, partly due to the heterogeneity of concepts and the subjectivity of each of the symptoms., (Copyright © 2020 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.)

The coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus2 (SARS-CoV-2) virus. COVID-19 affected more than 6million persons worldwide in fewer than 4 months, after the report of the first cases in China in December 2019. The relation of the disease caused by SARS-Cov-2 to immunosuppressive treatment used in different gastrointestinal disorders is uncertain, resulting in debate with regard to suspending immunosuppressive therapy to improve infection outcome. Said suspension implies the inherent risk for graft rejection or autoimmune disease exacerbation that can potentially worsen the course of the infection. Based on the presently available evidence, a treatment stance has been established for patients with gastrointestinal diseases that require immunosuppressive therapy., (Copyright © 2020 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.)

More than 30 million persons worldwide take nonsteroidal anti-inflammatory drugs (NSAIDs) on a daily basis, and annual consumption is increasing. In addition to their analgesic and anti-inflammatory properties, NSAIDs also produce well-known gastrointestinal adverse events. There is no consensus in Mexico on the diagnosis, treatment, and prevention of NSAID-induced gastropathy and enteropathy, and so the Asociación Mexicana de Gastroenterología brought together a group of experts to establish useful recommendations for the medical community. Thirty-three recommendations were formulated in the present consensus, highlighting the fact that the risk for NSAID-induced gastrointestinal toxicity varies according to the drug employed and its pharmacokinetics, which should be taken into account at the time of prescription. The risk factors for gastroduodenal complications due to NSAIDs are: a history of peptic ulcer, age above 65 years, high doses of NSAIDs, Helicobacter pylori infection, and the presence of severe comorbidities. The symptoms and gastroduodenal damage induced by NSAIDs vary, ranging from an asymptomatic course to the presentation of iron-deficiency anemia, bleeding, stricture, and perforation. Capsule endoscopy and enteroscopy are direct diagnostic methods in NSAID enteropathy. Regarding prevention, the minimum dose of an NSAID needed to achieve the desired effect, administered for the shortest period of time, is the recommendation. Finally, proton pump inhibitors are the gold standard for the prophylaxis and treatment of gastroduodenal effects, but they are not useful in enteropathy., (Copyright © 2020 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.)

Helicobacter pylori is associated with the development of several lesions in the human stomach. This chronic infection produces gastritis, which can progress to intestinal metaplasia and gastric cancer. To date, there is very little information regarding gene-expression in the different phases of progression caused by chronic H. pylori infection. In this study, we performed a genome-wide gene-expression analysis in gastric biopsies of patients chronically infected with H. pylori, using the potential of high-throughput technologies that have not been fully exploited in this area. Here we illustrate the potential correlation of H. pylori infection with the gene expression changes in follicular gastritis, chronic gastritis and intestinal metaplasia. We also suggest its potential as biomarkers of each condition. An exploratory set of 21 biopsies from patients with follicular gastritis, chronic gastritis, and intestinal metaplasia were analyzed by gene-expression microarrays in order to identify the biological processes altered in each lesion. The microarray data was corroborated by real-time PCR, while 79 Formalin-Fixed Paraffin-Embeded samples were analyzed by immunohistochemistry. Follicular gastritis exhibited significant enrichment in genes associated with glutamate signaling, while chronic gastritis showed a down-regulation in metallothionein 1 and 2 and in oxidative phosphorylation-related genes, which could be associated with the chronic infecton of H. pylori . Intestinal metaplasia exhibited an over-expression of gastrointestinal stem cell markers, such as LGR5 and PROM1 , as well as messenger RNA and nucleic acid metabolism-related genes. The gene-expression patterns found in this study provide new comparative information about chronic gastritis, follicular gastritis and intestinal metaplasia that may play an important role in the development of gastric cancer., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Milk is a liquid food that possesses an important quantity of highly bioavailable macronutrients. In addition, it is readily accessible, as well as relatively inexpensive. Given that the knowledge of physicians about nutrition and food composition is deficient, in general, many of the dietary interventions recommended in diverse clinical settings lack a scientific basis. The aim of the present review was to produce a technical opinion that serves as a frame of reference to best sustain recommendations for consuming milk and dairy products as daily nutrition in the adult and older adult. The effects of milk and dairy products during the pediatric stage are not addressed in the present work. The Asociación Mexicana de Gastroenterología and the Asociación Mexicana de Gerontología y Geriatría jointly discussed and analyzed topics dealing with the legal designation of milk, the classification and nutritional profile of cow's milk, its nutritional characteristics, its consumption in the adult, intolerance to cow's milk, and associations of milk consumption with digestive tract alterations and other conditions. Finally, certain aspects of milk consumption in the older adult and its relation to overall health are briefly discussed., (Copyright © 2019 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.)

Celiac disease, celiac sprue, or gluten-sensitive enteropathy, is a generalized autoimmune disease characterized by chronic inflammation and atrophy of the small bowel mucosa. It is caused by dietary exposure to gluten and affects genetically predisposed individuals. In Mexico, at least 800,000 are estimated to possibly have the disease, prompting the Asociación Mexicana de Gastroenterología to summon a multidisciplinary group of experts to develop the "Clinical guidelines on the diagnosis and treatment of celiac disease in Mexico" and establish recommendations for the medical community, its patients, and the general population. The participating medical professionals were divided into three working groups and were given the selected bibliographic material by the coordinators (ART, LUD, JMRT), who proposed the statements that were discussed and voted upon in three sessions: two voting rounds were carried out electronically and one at a face-to-face meeting. Thirty-nine statements were accepted, and once approved, were developed and revised by the coordinators, and their final version was approved by all the participants. It was emphasized in the document that epidemiology and risk factors associated with celiac disease (first-degree relatives, autoimmune diseases, high-risk populations) in Mexico are similar to those described in other parts of the world. Standards for diagnosing the disease and its appropriate treatment in the Mexican patient were established. The guidelines also highlighted the fact that a strict gluten-free diet is essential only in persons with confirmed celiac disease, and that the role of gluten is still a subject of debate in relation to nonceliac, gluten-sensitive patients., (Copyright © 2018. Publicado por Masson Doyma México S.A.)

Important advances have been made since the last Mexican consensus on the diagnosis and treatment of Helicobacter pylori (H. pylori) infection was published in 2007. Therefore, the Asociación Mexicana de Gastroenterología summoned 20 experts to produce "The Fourth Mexican Consensus on Helicobacter pylori". From February to June 2017, 4 working groups were organized, a literature review was performed, and 3 voting rounds were carried out, resulting in the formulation of 32 statements for discussion and consensus. From the ensuing recommendations, it was striking that Mexico is a country with an intermediate-to-low risk for gastric cancer, despite having a high prevalence of H. pylori infection. It was also corroborated that peptic ulcer disease, premalignant lesions, and histories of gastric cancer and mucosa-associated lymphoid tissue lymphoma should be considered clear indications for eradication. The relation of H. pylori to dyspeptic symptoms continues to be controversial. Eradication triple therapy with amoxicillin, clarithromycin, and a proton pump inhibitor should no longer be considered first-line treatment, with the following 2 options proposed to take its place: quadruple therapy with bismuth (proton pump inhibitor, bismuth subcitrate, tetracycline, and metronidazole) and quadruple therapy without bismuth (proton pump inhibitor, amoxicillin, clarithromycin, and metronidazole). The need for antimicrobial sensitivity testing when 2 eradication treatments have failed was also established. Finally, the promotion of educational campaigns on the diagnosis and treatment of H. pylori for both primary care physicians and the general population were proposed., (Copyright © 2018 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.)

Background: Acute pancreatitis (AP), a disease that commonly requires in-hospital treatment, has been associated with a high incidence of abnormal cardiovascular findings (ACFs). We conducted a prospective study to explore the association of these findings with severity of the disease., Methods: Adult patients with AP diagnosis were prospectively enrolled in an observational study during an 8-month period in a tertiary care center. AP and its severity were defined according to the Revised Atlanta Classification of AP. Subjects were submitted to electrocardiographic, echocardiographic, and serologic testing during the acute period and a 3-month follow-up. The incidence of ACF was compared between two groups: (1) Mild and (2) moderate/severe cases., Results: Twenty-seven patients (mean age 48 ± 17 years) with AP were enrolled; 15 (55%) had mild and 12 (45%) had moderate/severe AP. During the acute episode, 67% had increased pro-brain natriuretic peptide levels; 52% had abnormal electrocardiographic findings; 48% had abnormal echocardiographic findings; and 18% had increased troponin I levels. There was no significant difference in the incidence of ACF between mild and moderate/severe groups. Nineteen patients (70%) had repeated follow-up testing, and most of the initial ACF did not persist., Conclusion: ACFs occur in an important proportion of patients during AP episodes. Future research should continue to focus in the association of ACFs and the severity of the disease., (Copyright: © 2017 SecretarÍa de Salud)

Background: The rate of compliance with a gluten-free diet in patients with gluten-related disorders is unknown in most Latin American countries., Objective: To study the adherence to a gluten-free diet of Mexican individuals with celiac disease and nonceliac gluten sensitivity at the time of their first medical and nutritional consultation at a tertiary referral center., Methods: A cross-sectional study was performed. A specific questionnaire was used to gather information on demographics, clinical condition, and self-reported adherence to a gluten-free diet, and to determine strict compliance and intentional or inadvertent gluten consumption. All questionnaires were applied by a nutritionist with expertise in gluten-related disorders., Results: Fifty-six patients with celiac disease and 24 with non-celiac gluten sensitivity were included. Overall, 46 (57.5%) subjects perceived themselves as strictly adherent; however, inadvertent gluten intake was frequent in both celiac disease and non-celiac gluten sensitivity patients (39.2 vs. 33.3%; p = 0.2). Intentional consumption was more prevalent in subjects with celiac disease (48.8 vs. 29.1%; p = 0.048) and individuals with non-celiac gluten sensitivity showed better adherence (37.5 vs. 12.5%; p = 0.035)., Conclusions: The importance of a gluten-free diet is underestimated by Mexican patients with celiac disease. The role of a team with expertise in gluten-related disorders is essential to identify inadvertent gluten intake.

Background: Serous cystadenoma is a benign pancreatic cystic neoplasm. Conservative management is favored. We studied the clinical characteristics and course of serous cystadenoma in patients undergoing surgery or conservative management only at an academic referral center., Methods: Patients presenting with serous cystadenoma in the years 2000-2013 were selected. Hospital records were evaluated for patient and serous cystadenoma characteristics., Results: A total of 22 patients with serous cystadenoma were identified. Mean age at diagnosis was 63 years and 82% were women. Diagnosis was incidental in 59%, and 18% presented with unspecific abdominal pain, 14% unexplained weight loss, 4.5% gastrointestinal obstructive symptoms, and 4.5% cholangitis. Location was pancreas body 36%, head 32%, tail 23%, and uncinate 9%. Mean serous cystadenoma diameter at diagnosis was 37 ± 23 mm. After diagnosis five patients underwent surgery. Initial size was similar between surgical and follow-up groups (p = 0.9). Four cases were lost to follow-up; 13 continued conservative management with a mean follow-up time of 54 ± 27 months. The initial and last serous cystadenoma size in the follow-up group remained similar (p = 0.9). Six cases presented significant tumor growth during follow-up (p > 0.05). All patients remained asymptomatic throughout follow-up. No malignancy or serous cystadenoma-related death occurred., Conclusions: Size change of serous cystadenoma was minimal and patients remained asymptomatic during follow-up. Surgery should be limited to symptomatic and selected cases.

Background: Hypercalcemia is a rare but well recognized cause of acute and chronic pancreatitis. Hypercalcemia-related pancreatitis is mainly caused by primary hyperparathyroidism. The prevalence of pancreatitis in hyperparathyroidism varies worldwide and additional disease-modifying factors may play a role in its development. In 1988 the prevalence of pancreatitis secondary to primary hyperparathyroidism at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ), a referral center in Mexico City, was 12.1% (95% CI: 6.7-21)., Objective: To describe the current prevalence of pancreatitis secondary to primary hyperparathyroidism at the INCMNSZ., Methods: We reviewed 385 cases of primary hyperparathyroidism seen at the hospital between 1987 and 2012., Results: 26 cases with acute or chronic pancreatitis associated with primary hyperparathyroidism were documented, with a prevalence of 6.7% (95% CI: 4.6-9.7), which was lower than the 12.1% previously reported. In the present study, 20% had a history of alcohol consumption, 10% of gallstones, and 20% of ureteral calculi, compared with the previously reported 32.0, 34.6, and 40.0%, respectively. The average calcium levels were 13.1 and 13.8 mg/dl in the previous and current series, respectively., Conclusions: We found a decrease in the prevalence of pancreatitis associated with primary hyperparathyroidism from 12.1% (95% CI: 6.7-21) to 6.7% (95% CI: 4.6-9.7).

Purpose: A 10-month-old girl with a Brachmann-Cornelia de Lange syndrome and a choroid plexus papilloma of the brain was studied at the Hospital Infantil de México Federico Gómez (HIMFG) in Mexico City., Methods and Results: Presumptive papilloma of the third ventricle was evidenced on CT and MR images and removed. Pathological analysis confirmed its origin. A posterior radiosurgery was required due to a tumor relapse. Karyotypes (GTG bands) of the patient and her parents undertaken at HIMFG were normal. Array comparative genomic hybridization (array CGH) analyses of blood DNA of the patient and her parents carried out at BlueGnome's Laboratory in Cambridge, UK, set in evidence amplification of genes SPNS2, GGT6, SMTNL2, PELP1, MYBBP1A, and ALOX15 in chromosome 17p of the patient. Since MYBBP1A is a proto-oncogene and ALOX15 participates in the development of cancer and metastases of tumors, further fluorescent in situ hybridization (FISH) analyses of these two genes were implemented at HIMFG. Amplification of the two genes was found in the tumor of the case under study but not in an unrelated papilloma of the choroid plexus., Discussion: Further analyses of the association of choroid plexus papillomas with disorders of psycho-neural development and its relationship to molecular genetic modifications at chromosome 17p are now under way at HIMFG.

Background: Ampulla of Vater's tumors (AVT) are rare and account for 0.2% of neoplasia in necropsies. The stage, comorbidities and surgical experience are crucial for prognosis. The aim of this work is to report the clinical characteristics, treatment and complication of a group of patients with AVT., Material and Methods: Patients with AVT were included in a retrospective manner. Descriptive statistics was used and data were shown as means and SD., Results: One hundred and six patients were included with a mean age of 58.5 +/- 14 years and 58% were women. Jaundice was the most common clinical data and it was present in 90% of cases. Two-thirds of patients underwent a Whipple surgical procedure. Complications of surgery were present in 35% of cases and abdominal sepsis and pancreatic fistulae were the most common (32% and 29%, respectively). Adenocarcinoma was the most common histological type and 39% of cases were in stage IV at diagnosis. Age higher or equal to 65 years was associated with less surgical possibilities. Melena at presentation was associated with a higher probability of surgical resection., Conclusion: The probability of surgical resection is lower in patients older than 65 years and higher in those with melena at the diagnosis.

Introduction: Bites by house pets can be lethal or cause a series of catastrophic events with severe sequels, such as the loss of a limb or a systemic infection which may be life-endangering, especially in the case of children being bitten., Presentation: A 2-year-old girl was attacked by a dog, causing lesions at the occipital region. This was treated initially as a superficial wound that became further complicated with two cerebellar abscesses. These abscesses required neurosurgical and antimicrobial treatment, with a satisfactory outcome., Conclusion: The precise and diligent evaluation of a lesion caused by an animal bite may prevent further life-endangering complications. To the best of our knowledge, there are no reports about cerebellar abscess caused by a dog bite. When cranial lesions are penetrating, an abscess must to be considered. We insist on the importance of medical evaluation and adequate treatment of such lesions.

Objective: To evaluate clinical evolution of pediatric patients diagnosed with glioblastoma multiforme (GBM) at Hospital Infantil de México Federico Gómez., Methods: Cases of patients treated from January to May, 2007, were included in this study. Variables analyzed were: age, diagnosis, size of tumor, histopathological description, degree of resection, time of stay in hospital, complications and outcome using Pearson's chi-squared test and logistic regression., Conclusion: Sixteen patients were identified. Mean age of presentation was 8.8. An increased frequency of complications was observed in younger patients and longer survival rates in patients with greater resections; main mode of presentation was directly related to intracranial hypertension; size of tumor was not related to evolution or outcome. Modern histological classifications especially designed for children are deemed necessary to accurately diagnose GBM.

The head of a newborn dolphin (Tursiops truncatus), that died shortly after birth was imaged using computed tomography (CT). Gross cross-sectional slices of the head were compared with the CT images to identify normal structures of the cranium, brain, and respiratory and digestive pathways. Labelled transverse CT images of the dolphin head are presented sequentially as a reference for normal anatomy.

Object: This study addressed the integration of sensory short-term memory (SSTM) and motor planning (MP) in the lateral cerebellar region, where the dentate nucleus is localized, and in the prefrontal cortex (PF)., Methods: Boucher and Lewis's test of SSTM and MP was administered pre- and postsurgically to 8 patients of either sex, between 5 and 19 years of age, with tumors of the cerebellum, PF (area 9 medial) or the parieto-occipital region, and on one occasion to 8 corresponding controls., Results: Whereas lesions of the midline portions of the cerebellum and of the parietal-occipital region did not appear to cause any cognitive defects, patients with lesions affecting either the lateral cerebellar region or PF exhibited statistically significant deficits of SSTM and MP., Conclusions: The lateral cerebellum seems to act in concert with PF to integrate different cognitive activities related to holding objects in SSTM and planning motor strategies in reference to them.

Introduction: More than 10 years ago, the goal of our work had been to obtain a tissue sample of infiltrating lesions of the brainstem that had been diagnosed using computerized axial tomography (CAT). At that time, biopsies were believed to be indispensable when starting treatment of tumors. With time our objectives changed. Biopsies remained necessary, since until 1 year before the writing of this article we had not had the benefits of magnetic resonance imaging (MRI) at our Hospital. We also decided that carrying out sound statistics, confirmed by biopsies, was in itself a good procedure, especially in a country in which, to date, no serial studies of brainstem tumors had been undertaken., Methods: We analyzed all of the patients diagnosed with posterior fossa tumors between March 1989 and March 2002 at the Hospital Infantil de México Federico Gómez (HIM). A preoperative TAC of the cranium was performed on every patient. Stereotactically-guided biopsies during tomography allowed precise control of penetration. Material obtained was sent to the Department of Pathology for analysis., Results: Fifty patients were diagnosed with infiltrating tumors of the brainstem: 30 cases of low-grade astrocytomas, 13 cases of high-grade astrocytomas, 2 cases of primitive neuroectodermic tumors, 2 cases of rhabdoid tumors, 1 case of ependymoma, and 2 patients had non-specified tumors. The most frequent symptoms and signs were ataxia and disturbances of the cranial nerves. There was no mortality caused by penetration, and follow-up studies of more than 5 years were carried out., Discussion: The results from our series were similar to those in the literature. In our case, follow-up studies were undertaken for longer periods. In the first section of our work, we suggest the need for stereotactic biopsies in order to arrive at a precise diagnosis in environments in which MRI may be unavailable., Conclusion: At present, presumptive diagnosis of infiltrating brainstem lesions may be adequately undertaken with imaging methods, such as MRI. However, we believe that a stereotactically-guided biopsy provides an accurate method for diagnosing lesions of the brainstem. In our case, this procedure has been carried out entirely in the tomography room, without any complications of disease or mortality.

Objective: To identify the clinical, laboratory and imaging characteristics of 41 patients with a pyogenic hepatic abscess., Research Design: Retrospective, descriptive., Setting: Instituto Nacional de Ciencias Médicas y Nutrición, Salvador Zubirán., Study Units: 41 patients with a pyogenic hepatic abscess., Main Measurements: The measurement of the following variables was carried out: previous background, period of evolution, symptoms, signs, laboratory studies, imaging, treatment, complications and evolution., Results: 41 patients were evaluated. The average age of the group was 52.5 years (SD = 14.3) and 30 (73%) were male. The most frequent associated disease was diabetes mellitus which was found in 15 patients (37%). The most frequent clinic data were: fever in 38 patients (93%), chills in 26 (63%) and pain in the upper right quadrant in 25 (61%). The most common source of the formation of the abscess was of biliary origin in six patients (15%) and the serum amoeba test was positive in 10% of the cases. The localization of the abscess in our series was as follows: 33 cases (81%) were from the right lobe, five (12%) from the left lobe, three (7%) from both lobes and 87% were solitary. The germ found more frequently was E. coli in five patients (15%). As for the treatment, puncture by computed tomography was carried out in 25 patients (61%), four patients had a surgery and the rest were treated only with antibiotics. Regarding mortality, only one patient died (2%) due to a septic shock., Conclusions: An association with diabetes mellitus was identified and the most frequent origin was biliary, these data have already been reported in other studies. On the other hand, mortality and morbidity rates in our study were low.

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.