Diarrea aguda en el lactante y preescolar / Acute diarrhea in toddlers and infants

Acute diarrhea (AD) is the increase in frequency and volume of bowel movements with decrease in their consistency that lasts less than 14 days. AD is a major public health problem and is still nowadays a cause of significant morbidity and mortality during childhood, especially in children with nutritional deficits. At a younger age, there is a greater susceptibility to diarrhea, which is more intense and more likely cause dehydration. The prevention and management of dehydration is the mainstay of treatment. The use of medications must be used with caution, analyzing individual cases and based on the best available evidence. We will analyze the subject with special emphasis on treatment according to scientific evidence.

La diarrea aguda (DA) se define como el aumento en la frecuencia y volumen de las deposiciones con disminución de la consistencia y que dura menos de 14 días. La DA es un gran problema de salud pública y es aún hoy en día una causa de importante morbimortalidad durante la infancia en especial en niños con déficits nutricionales. A menor edad hay mayor susceptibilidad de presentar diarrea, siendo ésta de mayor intensidad y con mayores posibilidades de producir deshidratación. La prevención y el manejo de la deshidratación es el pilar fundamental del tratamiento. El uso de medicamentos debe ser criterioso, analizando cada caso individual y basado en la mejor evidencia disponible. Analizaremos el tema con especial énfasis en el tratamiento según evidencia científica.

[Breath tests in children with suspected lactose intolerance]. / Análisis de test de aire espirado en niños con sospecha de intolerancia a la lactosa.

INTRODUCTION: Up to 70% of the world population is lactose intolerance. However, there are no epidemiological studies among Chilean pediatric population affected by this condition. OBJECTIVES: Clinical characterization of a series of children who underwent the lactose intolerance breath test for lactose intolerance study, establishing intolerance and malabsorption frequencies, the most frequent symptoms, and test performance depending on the origin. PATIENTS AND METHODS: Patients under 18 years old who took the lactose intolerance breath test in the Gastroenterology Laboratory of the Catholic University of Chile, and who were admitted due to clinically suspected lactose intolerance. Malabsorption was considered when there was as an increase of ≥20ppm above the baseline (H2) or ≥34ppm of H2 and methane (CH4) combined. Intolerance was considered when the above was associated with a symptom intensity score ≥7 during registration. RESULTS: The analysis included194 patients aged 1 to17 years of age. Of these, 102 (53%) presented with malabsorption, and 53 (27%) were intolerant. The frequency of lactose intolerance varied from 7.1 to 45.4%, and it occurred more frequently at older ages. The most common reported symptoms were abdominal pain, bloating and rumbling. DISCUSSION: Lactose malabsorption and intolerance can be investigated from the first years of life using the lactose breath test plus a symptom questionnaire. An increase in the frequency of intolerance with age, and a greater number of positive tests, if they were requested by a gastroenterologist, were observed.

Análisis de test de aire espirado en niños con sospecha de intolerancia a la lactosa / Breath tests in children with suspected lactose intolerance

Introducción: Un 70% de la población general presenta intolerancia a la lactosa; sin embargo, no existen estudios epidemiológicos en la población pediátrica chilena afectada por esta condición. Objetivos: Caracterizar una serie clínica de niños que acude a realizarse el test de aire espirado con lactosa para estudio de intolerancia a la lactosa, determinando la frecuencia de intolerancia y malabsorción, síntomas más frecuentes y rendimiento del test dependiendo de su origen. Pacientes y Método: Pacientes menores de 18 años que acudieron a realizarse el test de aire espirado con lactosa al Laboratorio de Gastroenterología de la Pontificia Universidad Católica de Chile, por sospecha clínica de intolerancia a la lactosa. Se consideró malabsorción un aumento ≥ 20 ppm sobre el nivel basal de hidrógeno (H2) o ≥ 34 ppm de H2 y metano (CH4) en conjunto y como intolerancia cuando lo anterior se asoció a la sumatoria de intensidad de síntomas ≥ 7 en el registro. Resultados: Se analizaron 194 pacientes entre 1 y 17 años de edad. De ellos, 102 (53%) pacientes resultaron malabsorbedores y 53 (27%) intolerantes. La frecuencia de intolerancia a la lactosa varió de un 7,1 a un 45,4%, con una mayor frecuencia a edades mayores. Los síntomas más reportados fueron dolor abdominal, meteorismo y borborigmo. Discusión: La malabsorción e intolerancia a lactosa se pueden pesquisar desde los primeros años de vida utilizando el test de aire espirado con lactosa asociado al cuestionario simultáneo de síntomas. Se puede observar un aumento en la frecuencia de intolerancia con la edad, además de una mayor positividad del examen si es solicitado por un gastroenterólogo.

Introduction: Up to 70% of the world population is lactose intolerance. However, there are no epidemiological studies among Chilean pediatric population affected by this condition. Objectives: Clinical characterization of a series of children who underwent the lactose intolerance breath test for lactose intolerance study, establishing intolerance and malabsorption frequencies, the most frequent symptoms, and test performance depending on the origin. Patients and Methods: Patients under 18 years old who took the lactose intolerance breath test in the Gastroenterology Laboratory of the Catholic University of Chile, and who were admitted due to clinically suspected lactose intolerance. Malabsorption was considered when there was as an increase of ≥ 20 ppm above the baseline (H2) or ≥ 34 ppm of H2 and methane (CH4) combined. Intolerance was considered when the above was associated with a symptom intensity score ≥ 7 during registration. Results: The analysis included194 patients aged 1 to17 years of age. Of these, 102 (53%) presented with malabsorption, and 53 (27%) were intolerant. The frequency of lactose intolerance varied from 7.1 to 45.4%, and it occurred more frequently at older ages. The most common reported symptoms were abdominal pain, bloating and rumbling. Discussion: Lactose malabsorption and intolerance can be investigated from the first years of life using the lactose breath test plus a symptom questionnaire. An increase in the frequency of intolerance with age, and a greater number of positive tests, if they were requested by a gastroenterologist, were observed.

D-lactoacidosis como complicación del síndrome de intestino corto / D-lactoacidosis as short bowel syndrome complication

Short bowel syndrome is defined as the loss, congenital or acquired, anatomical or functional, of a large part of the small intestine that generates inadequate absorption of nutrients and the frequent need of prolonged parenteral nutrition. The etiology of short bowel is diverse and varies with age. The necrotizing enterocolitisis and the midgut volvulus are among the most frequent causes. The bacterial overgrowth is frequently observed in children with short bowel, due to the secondary dilation of the remaining small bowel and to the associated intestinal dysmotility. It is more frequent in absence of the ileocecal valve. We present a 6-year-old boy with short bowel syndrome secondary to extensive intestinal resection after a volvulous of the medium small intestine, 9 months before admission to the hospital, and who was on cyclical parenteral nutrition at home. The child developed ataxia, disarthria, dizziness and conscience compromise been admitted to de intensive care unit in deep sopor. An extensive work up including metabolic, infectious, toxicology and SNC imaging was negative except for metabolic acidosis. He was discharged on good conditions. Even though the child was on supportive therapy, the patient was readmitted few hours later with similar symptoms. D-lacto acidosis was suspected and confirmed with a value of 6.69 mmol/1 (normal range: 0,0-0,25). Literature about this uncommon complication and its mechanism is reviewed. D-lacto acidosis should be suspected in every patient with short bowel syndrome and unexplained metabolic acidosis associated with neurological symptoms.

El síndrome de intestino corto se define como la pérdida, congénita o adquirida, anatómica o funcional, de una extensa área del intestino delgado que genera inadecuada absorción de nutrientes y la frecuente necesidad de nutrición parenteral prolongada. Su etiología varía con la edad. Entre las causas más frecuentes están la enterocolitis necrotizante y el vólvulo de intestino medio. El sobrecrecimiento bacteriano es frecuente en estos pacientes, debido a la dilatación secundaria del remanente de intestino delgado y a la dismotilidad intestinal asociada. Objetivo: Comunicar un caso de acidosis D-láctica en un niño con Intestino corto. Caso clínico: Niño de 6 años con antecedente de intestino corto secundario a resección intestinal por vólvulo de intestino medio 9 meses previos al ingreso y que estaba recibiendo nutrición parenteral domiciliaria ciclada. El niño desarrolló ataxia, disartria, mareos y compromiso de conciencia, ingresando a la unidad de cuidados intensivos en sopor profundo. Un extenso estudio metabólico, infectológico, toxicológico y de neuroimágenes fue negativo, excepto por acidosis metabólica. Fue dado de alta en buenas condiciones. A pesar del tratamiento de soporte vuelve a ingresar horas después con similar cuadro clínico. Se sospecha y confirma elevación de D-lactato en sangre (6,69 mmol/1 con rango normal de 0,0-0,25). Se revisa la literatura acerca de esta infrecuente complicación y su mecanismo de producción. La D-lactoacidosis debiera ser sospechada en todos los pacientes portadores de intestino corto que presenten un cuadro de acidosis metabólica no explicada, especialmente si se acompaña de compromiso de conciencia y síntomas cerebelosos.

Infecciones virales intestinales en pediatría / Intestinal viral infections in pediatrics

Los virus que causan diarrea en humanos generalmente muestran gran trofismo por las células epiteliales del intestino delgado. El mecanismo tradicionalmente aceptado es que estos agentes causan enfermedad destruyendo gran cantidad de entericitos maduros, (sea por lisis directa o induciendo la apoptosis) los que son reemplazados por células inmaduras provenientes de las criptas. Esto lleva a una absorción inadecuada de agua, electrolitos y nutrientes, con capacidad conservada de secretar cloro y agua. A diferencia de lo que ocurre frente a patógenos bacterianos invasores, la respuesta inflamatoria del huésped es leve y no contribuye significativamente en el mecanismo de la diarrea viral. Estudios posteriores han llevado a postular mecanismos adicionales, que no serían autoexcluyentes. Se ha descrito que algunas proteínas virales no estructurales actuarían como enterotoxina. Además, jugaría un rol la alteración de las uniones estrechas con aumento del flujo paracelular de agua y electrolitos, el aumento de la secreción intestinal mediada por neurotransmisores, y la microisquemia vellositaria. El impacto de la enteritis viral es mayor y la recuperación más lenta en niños previamente desnutridos. Se ha demostrado en animales de experimentación desnutridos un notorio retraso en la recuperación de la capacidad enzimática y absortiva de la mucosa intestinal frente a una enteritis viral, lo que refuerza la necesidad de una temprana y efectiva rehabilitación nutricional durante los episodios agudos de diarrea. Es ampliamente conocido que la lactancia materna, disminuye la incidencia y severidad de las diarreas virales en niños, los primeros meses de vida.

Viruses that cause diarrhea in humans generally show great tropism due to epithelial cells of the small intestine. The traditionally accepted mechanism is that these agents cause illness by destroying large number of mature enterocytes (via direct lysis or by inducing apoptosis), which are replaced by immature cells coming from the crypts. This leads to an inadequate absorption of water, electrolytes and nutritients with conserved chloride and water secretion. In contrast to invasive bacterial pathogens, the host infl amatory response is mild and it does not contribute significantly to the mechanism of viral diarrhea. Subsequent studies have leaded to postulate additional mechanisms that would not exclude each other. It has been described that some non-structural viral proteins may act as enterotoxin. In addition, the alteration of the tight junctions with an enhanced paracellular flow of water and electrolytes, the increase of neurotransmitter mediated intestinal secretion, and the micro-ischemia of villi would also play a role. The impact of viral enteritis is larger and the recovery slower in previously undernourished children. Studies carried out on undernourished experimentation animals have demonstrated a notorious delay in the recovery of the enzymaticand absorptive capacity of intestinal mucosa after viral enteritis, which reinforces the need for early and effective nutritional rehabilitation during episodes of acute diarrhea. It is well-known that the breastfeeding reduces the incidence and severity of viral diarrheas in children during the first months of life.