Lactulose hydrogen breath test and functional symptoms in pediatric patients.

BACKGROUND: The role of small intestinal bacterial overgrowth (SIBO) in functional digestive disorders in the pediatric population is a matter of controversy, since methods currently used to establish this diagnosis are difficult to interpret. The aim of this work was to analyze the characteristics of the lactulose H(2) breath test (LHBT) in children with functional gastrointestinal symptoms according to more recent criteria. METHODS: Seventy-two patients and 17 controls were enrolled. A questionnaire was administered regarding digestive symptoms (abdominal pain, bloating, vomiting, and bowel-movement disorders). A lactose hydrogen breath test was performed to rule out lactose malabsorption and a LHBT was used to measure the time elapsed between lactulose oral ingestion and an increment of H(2) concentration of 20 ppm over basal. RESULTS: There were no differences of age and gender between patients and controls. Mean time to 20-ppm change was shorter in patients (56.3 ± 3 min) compared to healthy children (74.7 ± 5 min), p\0.05. In 39% of patients, rise of H(2) occurred during the first 40 min after lactulose ingestion, and in almost all controls, an increment was observed between 50 and 90 min (p\0.05). Symptoms were unrelated to time to 20-ppm change. CONCLUSIONS: An abnormal LHBT was found in children with functional symptoms of the digestive tract, but the exact mechanism involved, accelerated intestinal transit or SIBO, needs to be confirmed by an additional method.

Lactose malabsorption, calcium intake, and bone mass in children and adolescents.

OBJECTIVES: The objective of the present study was to evaluate the calcium intake and bone mass in children and early adolescents in accordance with their absorption capacity to lactose. PATIENTS AND METHODS: A transversal study was conducted on a sample composed of 76 individuals. Lactose malabsorption status was determined with hydrogen breath test. The hydrogen breath test was applied using 2  g of lactose per kilogram of weight up to a maximum of 50  g. A hydrogen increment ≥20  pm in relation to fasting was used to characterize lactose malabsorption. Two 24-hour recalls were applied for the evaluation of food consumption. Bone mineral content and bone mineral density were evaluated in the lumbar spine by dual-energy x-ray absorptiometry. RESULTS: The prevalence of lactose malabsorption was 61.8%. The participants were divided into 2 groups: lactose malabsorbers (n = 47) and lactose absorbers (n = 29). There was no statistically significant difference (P > 0.05) between the groups with respect to the intake of total calcium, milk calcium, milk, cheese, yogurt, ice cream, and calcium density of the diet. Additionally, there was no difference with respect to the bone mineral content and the bone mineral density of the lumbar spine. Independent from lactose absorption capacity, it was observed that the majority of the children and early adolescents showed calcium intake lower than the recommended value. CONCLUSIONS: There was no relation among lactose malabsorption and bone densities, bone mineral content, or calcium intake within the present study.

Intolerancia a la lactosa / Lactose intolerance

La lactosa es un disacárido de amplia distribución en la dieta y productos farmacéuticos, es el hidrato de carbono de la leche de los mamíferos. La intolerancia a la lactosa puede presentarse como congénita, hipolactasia del desarrollo, primaria y secundaria. Frente a la sospecha de ésta patología la clínica es lo principal, pudiendo investigarla a través de la prueba contraprueba, la prueba de hidrógeno espirado, la biopsia y por estudio de polimorfismos a través biología molecular (aún en estudio). Su tratamiento consiste en la disminución o exclusión de lactosa, uso de suplementos lácteos, sin olvidar la ingesta mínima requerida de calcio y vitamina D importantes en el desarrollo óseo.

Intolerancia congénita a la lactosa y hepatoesplenomegalia. A propósito de un caso / Congenital intolerance to lactose and hepatosplenomegaly

Se describe el caso de un lactante con intolerancia congénita a la lactosa que se presentó con mal ascenso ponderal, vómitos y hepatoesplenomegalia. Los exámenes complementarios mostraron proteinuria, movilización de enzimas hepáticas, cuerpos reductores en orina positivos correspondientes a lactosa y aminoaciduria generalizada. La inmediata institución de dieta libre de lactosa, fue seguida de una rápida recuperación clínica y paraclínica. La intolerancia congénita a la lactosa (ICL) es un raro trastorno de intolerancia a los azúcares. La afección fue descrita por Durand en 1958. Se caracteriza clínicamente por vómitos y mal ascenso ponderal con lactosuria, de inicio en los primeros días de vida siempre que el paciente esté alimentado con leche materna o fórmula con lactosa. Se acompaña de compromiso renal dado por aminoaciduria generalizada y acidosis tubular, hepático dado por movilización de transaminasas y en algunos casos compromiso ocular. Se subraya la importancia de descartar esta afección en los casos de vómitos y desnutrición de los primeros meses de vida dado que es una enfermedad potencialmente fatal si no se suprime el aporte alimentario de lactosa. (AU)

Intolerância à lactose: uma breve revisão para o cuidado nutricional / Lactose intolerance: a brief review for the nutritional care

A intolerância à lactose é uma inabilidade para digerir completamente a lactose, o açúcar predominante do leite. A lactose é um dissacarídeo e sua absorção requer hidrólise prévia no intestino delgado por uma b-galactosidase da borda em escova, comumente chamada lactase. A deficiência de lactase conduz à má-digestão da lactose e à conseqüente intolerância. A lactose não digerida, conforme passa pelo cólon, é fermentada por bactérias colônicas, havendo produção de ácidos orgânicos de cadeia curta e gases. Isto resulta em cólicas, flatulência, dor e diarréia osmótica. Existem dois tipos de deficiência de lactase. A deficiência de lactase do tipo primário é uma condição permanente. A forma congênita de deficiência de lactase é muito rara, enquanto a não persistência de lactase do tipo adulto é muito comum e afeta cerca de ¾ da população mundial. A deficiência de lactose secundária é, usualmente, condição temporária causada por dano à mucosa intestinal. Iogurte e outros produtos fermentados, bem como leites hidrolizados, amenizam os sintomas dos intolerantes. Da mesma forma, ingerir pequenas quantidades de leite a cada vez, ingerir leite juntamente com as refeições, usar preferencialmente leite integral e acrescentar chocolate ao leite podem aumentar a tolerância à lactose. Por outro lado, fatores psicológicos devem ser considerados no que diz respeito à intolerância à lactose, já que é sabido que as funções cerebrais exercem forte influência sobre a percepção de sintomas. Este trabalho revisa informações fundamentais sobre má digestão da lactose e intolerância à lactose e discute as possibilidades no tratamento dos intolerantes

[Importance of nutritional status in digestion capacity and lactose tolerance]. / Importancia del estado nutricio en la capacidad de digestión y tolerancia a la lactosa.

The aim of this study is to determine the capacity of undernourished patients to digest and tolerate the lactose in milk administered by tube-feeding. It was a controlled double-blind crossover trial in 25 hospitalized patients who required enteral feeding due to medical reasons. They were divided in two groups differing by nutritional status: 10 patients in Group 1 were malnourished with a mean weight for height of 69% (+/-15% SD) of their ideal one; Group 2 had 15 well nourished patients (mean weight for height of 103 +/- 15%). Each patient received two dietary treatments: intact milk and hydrolyzed milk (> 90% of lactose hydrolyzed). Lactose digestion was measured by the hydrogen breath test. Hydrogen excretion with intact milk was 505 +/- 117 ppm in Group 1 versus 58 +/- 15 ppm in the control group. With hydrolyzed milk, these values were 53 +/- 27 and 14 +/- 23, respectively. The scoring of symptoms after drinking intact milk was 4.3 +/- 0.7 in Group 1 vs 1.5 +/- 0.3 in Group 2, and they were lower with hydrolyzed milk (0.5 +/- 0.2 vs 0.3 +/- 0.2 respectively). The undernourished group had a higher incidence of both lactose maldigestion (p < 0.0001) and lactose intolerance (p < 0.001) than the control group. Our results strongly suggest that undernourishment is accompanied always or almost always by lactose intolerance.

Intolerancia a la lactosa. Su definición, su prevalencia en México y sus implicaciones en el consumo de leche / Lactose intolerance. Definition, prevalence in Mexico, and its implications in milk comsumption

El presente trabajo describe los aspectos de intolerancia a la lactosa y a la leche, discute los resultados de estudios llevados a cabo anteriormente en México, y detalla un estudio cuyo objetivo fue cuantificar el impacto de la intolerancia a la lactosa sobre el consumo habitual de leche. Se estudió la prevalencia de intolerancia a la lactosa y su efecto sobre el consumo de leche en tres regiones de México. El diseño del estudio fue prospectivo, aleatorio, doble ciego y cruzado. Se estudió la presencia de intolerancia a la leche en 960 sujetos entre 6 meses y 99 años de edad quienes recibieron según su edad, una cantidad de 240 ó 360 mL de leche intacta y la misma cantidad de leche hidrolizada. Se registró el patrón de consumo de leche y la presencia de síntomas después de cada tratamiento. De los sujetos estudiados, el 7 por ciento manifestaron síntomas de intolerancia después de la ingestión de leche intacta. La presencia de síntomas intensos en los sujetos intolerantes redujo en forma significativa (p< 0.001) el consumo de leche en comparación con los sujetos tolerantes. La presencia de síntomas con leche hidrolizada se redujo al 2 por ciento (p< 0.001). Se concluye que la intolerancia a la lactosa no es determinante para el consumo de leche en la población sana de México

Deficiencia secundaria de lactosa en niños y sus implicaciones epidemiológicas / Secondary lactase deficiency and its epidemiological implications

Se revisan las contribuciones que han tenido mayor relevancia en el conocimiento de la deficiencia secundaria de lactasa en los niños. Se hace referencia a la identificación de las diarreas fermentativas, a la descripción de sus particularidades clínicas, a la explicación de sus características fisiopatológicas, a los procedimientos para su diagnóstico, y a su manejo dietético. Se mencionan las enfermedades en cuyas manifestaciones clínicas se asocian las del síndrome por deficiencia de lactasa; con base en esta información, se hacen algunos planteamientos acerca de la magnitud y trascendencia epidemiológica de este problema

Absorción intestinal deficiente de lactosa (AIDL) en niños con diarrea aguda sin deshidratación / Lactose deficient intestinal apsortion in children with acute diarrhea without dehydration

Se estudiaron 55 niños con diarrea aguda sin deshidratación para determinar si presentaban o no absorción intestinal deficiente de lactosa (AIDL) por medio de la prueba de iones hidrógeno en aire espirado. La AIDL se encontró en 24/55 niños. Al contrastar la prueba de iones hidrógeno en aire espirado contra pH y azúcares reductores en heces para el diagnóstico de AIDL, no hubo diferencias estadísticamente significativas. Rotavirus fue el agente patógeno más frecuentemente involucrado (12/55 casos); sin embargo, sólo en dos se demostró AIDL. Se formaron dos grupos de acuerdo al resultado de la prueba. Grupo I, sin AIDL y Grupo II con AIDL. Al primero se le administró leche entera, leche modificada o ambas en proteínas con lactosa y el grupo II se dividió en tres subgrupos alimentados con fórmulas con lactosa, sin lactosa y soya sin lactosa. No hubo diferencias estadísticamente significativas en la frecuencia de niños por la prueba de iones hidrógeno, en tanto que en 5/24 niños ocurrió entre la 2a y 4a semana y en 2/24 en la semana 9 y 10. por lo tanto, el empleo de fórmulas sin lactosa, o sin soya ni lactosa en niños con diarrea aguda sin deshidratación no parece justificarse

Lactose maldigestion and milk intolerance: a study in rural and urban Mexico using physiological doses of milk.

Lactose digestion capacity after ingestion of physiological doses of milk and its effect on milk intolerance and consumption were studied in rural and urban populations from three regions of Mexico with different milk intakes. All subjects (n = 926) received two treatments: whole milk (240 mL for children and 360 mL for adults) and the same amount of 90% lactose-hydrolyzed milk; 72% of the subjects also received as a third treatment a water solution containing lactulose (8 g for children and 10 g for adults). Lactose maldigestion determined by a hydrogen breath test was detected in 2 to 43% of subjects (depending on age group) and was higher in subjects from central and southern Mexico than in subjects from northern Mexico (P < 0.01). Only the experience of major symptoms of intolerance affected milk consumption, and these symptoms were present in 0 to 11% of children > 4 y old and in 7 to 17% of the 13- to 60-y-old subjects. No significant differences were found in lactose maldigestion or milk intolerance between rural and urban populations, but milk consumption was higher in urban areas (P < 0.01). Milk consumption in our study was affected primarily by factors not related to the capacity to digest or tolerate the lactose in milk.

Adaptaçäo de ratos, após desmame, à raçäo com concentraçäo elevada de lactose: I. Avaliaçäo da ingestäo de água e raçäo / Adaptation of weaned rats to prolonged lactose ingestion: I. Estimation of water and diet ingestion

Para o estudo foram empregadas 12 ratas Wistar, desmamadas com 21 dias de vida, que após 2 dias de adaptaçäo no laboratório foram dividas em dois grupos. Grupos Lactose: constituído de seis animais recebendo durante 4 semanas raçäo adicionada de lactose, na proporçäo de 25 g/100 g de peso final da mistura. Para a mistura foi empregada raçäo normalmente utilizada na alimentaçäo destes animais após o desmame. Grupo Sacarose: constituído também de seis animais recebendo adiçäo da sacarose por período idêntico e na mesma proporçäo que no grupo anterior. Os animais foram pesados no início, 7§, 14§, 21§ e 28§ dias de experiência. Exceto no início, nestes mesmos dias foram avaliadas individualmente a ingestäo relativa de água e raçäo em 24 horas. Os animais do Grupo Lactose, durante o període de observaçäo, apresentaram ganho ponderal significativamente mais baixo, com tendência da diferença a diminuir em relaçäo ao Grupo Sacarose, no final do período de observaçäo. A ingestäo de raçäo, no Grupo Lactose, foi significativamente mais elevada no 21§ e 28§ dias, contrariamente a de água que ocorreu no 7§ e 14§ dias. Os resultados sugerem que, apesar da queda ontogênica da lactase, ratos podem acomodar-se à ingestäo alta de lactose após o desmame, utilizando mecanismos de adaptaçäo que merecem ser investigados

[Adaptation of rats, after weaning, to a diet with a high concentration of lactose. I. Evaluation of water and diet ingestion]. / Adaptação de ratos, após desmame, à ração com concentração elevada de lactose. I. Avaliação da ingestão de água e ração.

Twelve female Wistar rats, weaned at 21 days, were allocated in two groups: Lactose Group composed by six rats receiving a normal laboratory diet added with 25 g of lactose for each 100 g of final mixture, and the Saccharose Group that was fed with the same diet but with the lactose being replaced by saccharose in the same proportion; both groups were studied for 28 days. The rats were weighed at the beginning of the experiment and on the 7th, 14th, 21st and 28th days; the relative ingestion of water and diet was evaluated for each animal on the same days except for the first. During the observation period weight gain was significantly lower on the Lactose Group compared to the Saccharose Group, although this difference became less evident towards the end of the experiment. In the Lactose Group the diet ingestion was higher on the 21st and 28th days opposed to the water ingestion which was higher on the 7th and 14th days. The results here presented suggest that, in spite of the ontogenic fall of intestinal lactase in rats, these animals can, even after weaning, accommodate to high doses of dietary lactose, by using adaptative pathways which deserve further investigation.