Síndrome de intestino irritable (SII): nuevos conceptos sobre una antigua enfermedad / Irritable bowel syndrome (IBS): new concepts on an old disease

El síndrome de intestino irritable es un cuadro clínico frecuente caracterizado por malestar/dolor y ditensión abdominal, diarrea, constipación o alternancia de estos síntomas. Tiene un carácter crónico recurrente. El diagnóstico se basa en el cuadro clínico y en la ausencia de síntomas y signos patológicos en los exámenes de rutina. La fisiopatología es compleja y no totalmente esclarecida, reconociéndose la importancia del estrés emocional, las alteraciones de la relación flora intestinal/sistema inmune de la mucosa intestinal y en algunos casos el antecedente de una infección entérica. Es de buen pronóstico y su tratamiento es sintomático. Es importante una óptima relación médico/paciente.

The irritable bowel syndrome is a clinical entity characterized by abdominal distention and pain/discomfort associated with changes in the bowel habit, diarrhoea, constipation or alternating of these symptons. It is a chronic and recurrent condition. Diagnosis is based in the clinical presentation and in the absence of symptoms and signs of severity. The pathophysiology is complex and not completely elucidated although the importance of psychological stress and changes in the relationship of the intestinal flora with the intestinal mucosal immune system are recognized. In some cases a history of intestinal infections is identified. The treatment is addressed to control the symptoms and the prognosis is good. An optimal relationship between the doctor and the patient is of paramount importance.

Esófago de Barrett: la antesala del adenocarcinoma de esófago / Barrett's esophagus: a risk factor for esophageal adenocarcinoma

El esófago de Barrett (EB) es una complicación frecuente de la enfermedad por reflujo gastroesofágico y es un factor importante en el desarrollo de adenocarcinoma esofágico. El EB es sospechado por los hallazgos en la endoscopia y su diagnóstico se confirma cuando la histología demuestra la presencia de metaplasia intestinal en la mucosa esofágica. Dado que la mayoría de los pacientes con EB no desarrollará cáncer de esófago, es necesario definir nuevas estrategias que ayuden a identificar pacientes de mayor riesgo. Aunque la vigilancia de los pacientes con EB está basada aún en la toma sistemática de biopsias de la mucosa con metaplasia, nuevas técnicas endoscópicas de alta resolución pueden ayudar en el proceso de selección. El tratamiento endoscópico de la displasia en pacientes con EB es una nueva modalidad que espera mayor estudio para precisar su indicación.

Barrett's esophagus (BE) is a common complication of gastroesophageal re flux disease and is a major risk factor in the development of esophageal adenocarcinoma. BE is detected on endoscopy and confirmed when histology shows intestinal metaplasia. The majority of Barretts patients will not develop cancer of the esophagus, so new specific methods of identification of those at risk are needed. Although the surveillance of patients with BE is still based on systematic biopsy sampling of Barrett's mucosa endoscopy.

Barostato rectal en el síndrome de intestino irritable / Rectal barostat in irritable bowel syndrome

Background: Many patients with irritable bowel syndrome (IBS) have lowered sensory thresholds to rectal distention when compared to control subjects, a phenomenon called visceral hypersensitivity. Aim: To investigate the usefulness of a rectal barostat as a diagnostic tool in IBS and if there are differences in visceral hypersensitivity in different groups of IBS patients. Patients and Methods: Ten healthy subjects and 19 IBS patients, defined using Rome II criteria (12 with constipation, three with diarrhea and four alternating between diarrhea and constipation), were studied. Sequential isobaric rectal distentions, from 2 mmHg up to a maximal pressure of 52 mmHg or when the patients reported pain, were carried out. Visceral hypersensitivity was defined as a pain threshold under 38 mmHg. Results: Only 26 percent of IBS patients had visceral hypersensitivity (16 percent and 43 percent of patients with IBS and constipation and IBS and diarrhea or alternating symptoms, respectively, p =NS). Pain threshold in controls, patients with IBS and constipation and patients with IBS and diarrhea or alternating symptoms was 43.8±6.6, 45.3±9.2 and 40.8±9.2 mmHg, respectively (p =NS). Conclusions: Our results do not support the usefulness of the electronic rectal barostat as a diagnostic method to diagnose IBS.

Tromboembolismo, otra manifestación extraintestinal de las enfermedades inflamatorias intestinales / Thromboembolism, another extraintestinal manifestation of inflammatory bowel disease

El tromboembolismo (TE) arterial y venoso, posee una elevada morbimortalidad, siendo en pacientes con enfermedades inflamatorias intestinales (EII) 3-4 veces mayor que la población general, con una prevalencia de un 2-10 por ciento. El mecanismo por el cual la actividad procoagulante está aumentada en las EII es aún desconocido, sin embargo, factores de riesgo como el grado de inflamación de la mucosa han sido descritos. Objetivos: Determinar las características clínicas de TE en un grupo de pacientes con EII. Pacientes y Métodos: Se analizaron de manera retrospectiva los antecedentes clínicos de 16 pacientes con EII que presentaron TE durante su evolución. Se evaluó edad, extensión y grado de actividad de la EII al momento del TE. Resultados: Los pacientes estudiados fueron 13 con colitis ulcerosa (CU) y tres con enfermedad de Crohn (EC), edad promedio 43 años (rango 21-72), ocho mujeres. Once pacientes tenían < 50 años al momento del TE. En CU, nueve pacientes tenían pancolitis, todos con enfermedad activa moderada-severa. En EC, dos pacientes presentaban actividad de la enfermedad al momento del TE. Tres pacientes tenían otra manifestación extraintestinal (MEI), dos de ellos artralgias y uno colangitis esclerosante primaria. Los eventos de TE son: trombosis venosa profunda de extremidades inferiores en 9 casos; TE pulmonar en 3 pacientes, trombosis mesentérica/portal (dos casos), trombosis del seno venoso longitudinal (un paciente), trombosis arteria cerebral (uno) y trombosis de arteria braquial un caso). Quince casos de TE ocurrieron entre una semana y 6 años luego del diagnóstico de EII. Cinco pacientes estaban hospitalizados al momento del TE, dos de ellos después de cirugía por su EII. Ningún paciente estaba recibiendo nutrición parenteral total o tenía catéter venoso central al momento del TE. El estudio de trombofilia realizado en cinco pacientes, no demostró alteraciones características. Todos los pacientes fueron tratados con heparina sin complicaciones, y un paciente falleció por embolia pulmonar. Ningún paciente tenía antecedentes personales o familiares de TE. Conclusiones: El tromboembolismo es otra MEI de las EII que debe ser sospechado. La remisión de la EII pudiera ser el factor más importante en la prevención de estos episodios. El uso de heparina como tratamiento del TE no está contraindicado en estos pacientes, incluso en aquellos con crisis severa con sangramiento intestinal.

Enfermedades inflamatorias intestinales: experiencia de dos centros chilenos / Inflammatory bowel disease: experience of two chilean centers

Background: The incidence of Inflammatory Bowel Disease (IBD) has increased, particularly in the developed world, and probably also in Chile. Aim: To report our experience with a large group of patients from two medical centers, Hospital Clinico de la Universidad de Chile (HCUCH) and Clinica Las Condes (CLC) and to characterize the clinical features of IBD in Chile. Patients and methods: Retrospective review of 238 patients with IBD (age range 14-78 years, 143 women) treated at HCUCH and CLC between January 1990 and August 2002. Results: One hundred eighty one patients had ulcerative colitis (UC) and 57 had Crohn's disease (CD), with an UC/CD ratio of 3.2/1. Forty eight percent of patients were aged between 20 and 39 years old and 69% were diagnosed after 1995. Patients from HCUCH had more severe disease, more complications and needed surgery more often. Conclusions: Clinical features of Chilean patients with IBD are similar to those of other countries. UC is more common than EC. There is a higher proportion of women with the disease. The severity of the disease was higher among HCUCH.

Enfermedad Celíaca del adulto: experiencia clínica / Adult celiac disease: clinical experience

Background: The prevalence of celiac disease (CD) is unknown in Chile. We have recently noted a rise in the number of cases diagnosed among adults. Aim: To describe the clinical characteristics of a group of adult celiac patients. Patients and methods: Clinical data of patients older than 15 years with positive antitransglutaminase or antiendomysial autoantibodies and a duodenal biopsy characteristic of CD were retrospectively reviewed. Age at diagnosis, symptoms and signs and laboratory, endoscopic and histological findings, were analyzed. Results: Thirty seven patients (28 women), were studied. Median age at diagnosis was 41 years (range 15-69). Main symptoms and signs were diarrhea (78%), weight loss (38%) and abdominal pain (38%). Anemia was found in 49%, elevation of ESR in 57%, elevation of alkaline phosphatases in 54%, elevation of aspartate aminotransferase in 38% and a rise in alanine aminotransferase in 27%. Antiendomysial antibodies were positive in 17/22 (77%) and antitransglutaminase in 19/22 (86%) patients. Endoscopic findings were suggestive of CD in 47% of cases and duodenal biopsy showed intestinal villi atrophy in 34 (92%) patients. The three patients with normal histology had positive serology and a good response to gluten free diet. Conclusions: CD should be considered in the differential diagnosis of patients with unespecific digestive symptons, even when they present late in adult life. Serologic markers are a good diagnostic tool. A normal duodenal pathology does not exclude the diagnosis, if other diagnostic features are present.

Papel del sistema inmune en el desarrollo de las enfermedades inflamatorias intestinales / Role of the immune system in inflammatory bowel diseases development

Las enfermedades inflamatorias intestinales (EII), entre las que se incluyen a la enfermedad de Crohn (EC) y colitis ulcerosa (CU), son patologías de etiología multifactorial, en las cuales se ha demostrado en los últimos años que el componente genético tiene un papel relevante. La incidencia de estas patologías ha ido en aumento en los países desarrollados y también en Chile. A pesar de los avances en su estudio, la etiología de las EII no está totalmente esclarecida, aunque es posible reconocer factores genéticos, inmunológicos y ambientales en su patogénesis. Entre los posibles mecanismos propuestos la respuesta alterada a antígenos bacterianos cumpliría un papel relevante en un subgrupo de pacientes con EC quienes presentan alguna mutación en los receptores que reconocen patógenos. Esta revisión analiza avances recientes en el conocimiento de las EII y destaca los hallazgos relacionados con alteraciones en los componentes del sistema inmune gastrointestinal y su posible relación con la patogenia de las EII. Un análisis detallado de la interrelación entre los diferentes integrantes del sistema inmune de la mucosa intestinal, tales como las células dendríticas, epiteliales, de Paneth y los linfocitos T y su actividad defectuosa podría brindar nuevas herramientas para el diseño de estrategias experimentales y terapéuticas de las EII.

Helicobacter pylori: 20 años después / Helicobacter pylori: two decades later

Twenty years ago Helicobacter pylori was identified in the gastric content and this finding stimulated a multitude of studies and publications that changed drastically our knowledge of common gastric conditions such as peptic ulcer and gastric cancer. This progress has affected significantly our practice and has resulted in great benefits for our patients. The relationship of the bacteria to the pathogenesis of gastritis, peptic ulcer, gastric cancer and gastric lymphoma was firmly established. A large number of individuals are infected (an estimated half of the world's population) while only a minority suffers of the above mentioned conditions, so it became clear that certain strains of the bacteria, susceptibility of the host and environmental factors interplay in causing the damage. The diagnosis of the infection became a standard practice and therapy and prevention of these common conditions has been drastically modified. Eradication of the bacteria resulted in the cure of ulcers, in a dramatic decrease in the rate of its complications and in the ocurrence of gastric cancer. Better sanitary conditions are part of the solution. Also it is successful in the management of certain gastric lymphomas. The treatment however, is expensive and not free of side effects. Further research work is needed to facilitate the diagnosis and less expensive treatments should be available to eradicate Helicobacter pylori throughout the world.