Water consumption in pediatrics

Special considerations must be taken to calculate water require- ments of newborns and breastfeeding children; however, all their water needs should be covered with breast milk or breast-milk substitute formula. There is a need for 100 mL of water per 100 kcal consumed, or of 1,800 mL per square meter body surface area. From the age of six months, it is advisable to start providing 30 to 60 mL of water per day, with progressive increase; before that age, any other liquid must be avoided. Inadequate preparation of a substitute formula may cause hydric intoxication, or infections if the water used is contaminated. The increase in obesity and overweight is the result of increased intake of sugary beverages in children. This increased intake can also be linked to diabetes and other physiological and cognitive problems. Mexican children and teenagers have increased their caloric intake from sugary beverages in 126% between 1999 and 2006. As one of many healthy habits that children must acquire from home, is the avoi- dance of sugary beverages and the acknowledgment of water as a preferred hydration source

Utilidad de la recolección de orina de dos horas para el diagnóstico del tipo de acidosis tubular renal

La acidosis tubular renal se caracteriza por acidosis metabólica hiperclorémica. El diagnóstico del tipo de acidosis tubular renal se realiza mediante la medición del transporte tubular máximo de bicarbonato y de la capacidad de acidificación urinaria; sin embargo, estas pruebas son invasivas y requieren determinaciones especializadas. Objetivo: comparar la utilidad de la recolección urinaria de dos horas, una prueba relativamente simple y al alcance de muchos laboratorios, con la medición del transporte tubular máximo de bicarbonato y con la capacidad de acidificación urinaria (procedimientos de referencia) para clasificar el tipo de acidosis tubular renal en pacientes pediátricos. Material y método: el estudio se realizó en niños con diagnóstico de acidosis tubular renal. El primer día se recolectó la muestra sérica y urinaria de dos horas. Al día siguiente se efectuaron los procedimientos de referencia administrando bicarbonato de sodio en 8 horas; las muestras se colectaron cada hora y se determinaron la reabsorción de bicarbonato y la acidificación urinaria.  Resultados: se incluyeron 19 pacientes y en 17 casos la colección urinaria de dos horas confirmó el diagnóstico de los procedimientos de referencia. La recolección urinaria de dos horas tuvo sensibilidad de 0.94 y especificidad de 0.67 para el diagnóstico de acidosis tubular renal distal. Conclusión: la recolección de orina de dos horas se realiza en forma menos invasiva y ofrece resultados semejantes a los procedimientos de referencia

Generalidades de los estudios de casos y controles

ANTECEDENTES: los estudios de casos y controles son de utilidad cuando se buscan factores de riesgo para enfermedades poco comunes o que tienen un periodo de latencia prologado. OBJETIVO: identificar las principales características del estudio de casos y controles (Ca-Co) para favorecer la disminución de sesgos durante su evaluación o conducción. DESCRIPCIÓN: este diseño se caracteriza por la selección de sujetos con o sin el evento de interés. Éstos se comparan para identificar los factores de riesgo que favorecieron la presencia de este evento. La finalidad de este tipo de estudios es la de inferir una relación causal expresada mediante razón de momios y los intervalos de confianza al 95%. CONCLUSIONES: el diseño de Ca-CO es relativamente fácil y rápido de realizar. Sin embargo, es susceptible a múltiples fuentes de sesgo, las cuales deben de ser minimizadas para obtener mayor confiabilidad de las inferencias obtenidas

Frequency of renal tubular acidosis in children with down syndrome

Background: Down syndrome (DS) is associated with various congenital diseases and malformations, including those of the kidneys and urinary tract. It has been thought that renal tubular acidosis (RTA) is more frequent in this population. The objective of this study was to assess the frequency of RTA and, secondarily, of other renal and urological disorders in persons with DS. Method: An observational, ambispective, descriptive and cross-sectional study of patients diagnosed with RTA, or suspected kidney or urological disorders, was carried out from July 2016 to September 2017 at the Down syndrome clinic of the Mexican National Institute of Paediatrics. Urinalysis was performed, along with analyses of venous blood gas, sodium, potassium, chlorine, calcium, phosphorus, albumin and creatinine. Those with any abnormal values were referred to nephrology for diagnostic evaluation. Results: Of a total of 700 patients seen at the clinic, 47 met the selection criteria. Of these, 32 had no RTA or other renal or urological alterations. The remaining 15 continued to the second phase of the study, where 6 were diagnosed with nephropathy or uropathy (RTA, systemic arterial hypertension, monosymptomatic familial haematuria, mild renal failure secondary to reflux nephropathy, urinary tract infection or right ureteropelvic stenosis). Four had mild metabolic acidosis without meeting the criteria for diagnosis of RTA. Conclusion: RTA is not more common in children with Down syndrome. Nephropathies and uropathies should be investigated in the evaluation of DS patients

Prevalence of allergic diseases in children with secondary renal tubular acidosis attending a tertiary care pediatric center

Background: It has been suggested a high prevalence of allergic disease in children with RTA. Objectives: To describe the prevalence of allergic diseases in children with secondary RTA (renal tubular acidosis) in the nephrology department of the National Institute of Pediatrics (NIP), México. Methods: An observational, prospective, cross-sectional, descriptive study. Children with secondary RTA < 18 years who attended the outpatient nephrology service in the NIP for 24 months, were included. ISAAC questionnaire and the EAACI guidelines were applied. To prove a suspected allergy, skin tests, total and specific IgE, patch testing and food challenge were performed. Using SPSS 19, frequency of allergic diseases was described. Results: 113 patients were included. Age 8 to 168 months. Male: 53.9 %. RTA types: Distal (64.6 %), proximal (26.5 %), mixed (1.8 %) and undetermined (7 %). Age of onset between 1 and 96 months. Serum bicarbonate 10.1 to 20 mEq/L. Allergic diseases were found in 24.8 %: allergic rhinitis (18.4 %), food allergy (9.7 %), atopic dermatitis (8 %), asthma (8 %) and allergic conjunctivitis (6.1 %). Total IgE was increased in 9 patients. Positive skin tests in 14.2 %. Positive chemiluminescence in 18 children; positive open food challenge in 11 children and patch tests in 4. Conclusions: Secondary RTA is common in children attending tertiary care hospitals. The prevalence of allergic disease in children with secondary ATR, is similar to that described in the general population