Treating asthma patients with probiotics: a systematic review and meta-analysis / Tratamiento de pacientes asmáticos con probióticos: revisión sistemática y metaanálisis

Objective: to evaluate the role of probiotics in the treatment of asthma patients by meta-analysis.Methods: PubMed, Embase, The Cochrane Library, Web of Science, and other databases were searched by computer, and the relevant literature on the treatment of asthma by probiotics that met the inclusion criteria was screened by manual retrieval. Meta-analysis was performed using Revman 5.4 software and the combined effect was evaluated by odds ratio (OR) or mean difference (MD) and 95 % confidence interval (CI). Results: a total of ten references were included, all of which were randomized controlled studies, and a total of 1,101 people were investigated. Fractional exhaled nitric oxide (FeNO) (MD = -7.17, 95 % CI: -12.81, -1.54), asthma symptom severity (MD = -0.07, 95 % CI: -0.10, -0.04), Childhood Asthma Control Test (CACT) (MD = 2.26, 95 % CI: 1.14, 3.39), and the number of acute episodes of asthma (OR = 0.30, 95 % CI: 0.19, 0.47) in the probiotics group were better than those in the control group. There was no significant difference in forced expiratory volume in the first second (FEV1) (MD = 0.11, 95 % CI: -0.05, 0.26) and FEV1/FVC (%) (MD = 0.32, 95 % CI: -1.48, 2.12). Conclusion: the use of probiotics in patients with asthma can improve lung inflammation and asthma symptoms, reduce the number of asthma attacks, and have no effect on lung function.(AU)

Objetivo: evaluar el papel de los probióticos en el tratamiento de pacientes con asma mediante metaanálisis.Métodos: se realizaron búsquedas informáticas en PubMed, Embase, The Cochrane Library, Web of Science y otras bases de datos, y se examinó la literatura relevante sobre el tratamiento del asma con probióticos que cumplía con los criterios de inclusión mediante recuperación manual. El metaanálisis se realizó con el software Revman 5.4 y el efecto combinado se evaluó mediante la razón de probabilidades (OR) o diferencia media (MD) y el intervalo de confianza (IC) del 95 %. Resultados: se incluyó un total de diez referencias, todas ellas estudios controlados aleatorios, y se investigó un total de 1.101 personas. El óxido nítrico exhalado (FeNO) (MD = -7,17, IC 95 %: -12,81, -1,54), la gravedad de los síntomas del asma (MD = -0,07, IC 95 %: -0,10, -0,04), la Prueba de Control del Asma (CACT-ACT) (MD = 2,26, IC 95 %: 1,14, 3,39) y el número de episodios agudos de asma (OR = 0,30, IC 95 %: 0,19, 0,47) en el grupo de probióticos fueron mejores que en el grupo de control. No hubo diferencia significativa en volumen espiratorio forzado en el primer segundo (FEV1) (DM = 0,11, IC 95 %: -0,05, 0,26) y FEV1/FVC (%) (DM = 0,32, IC 95 %: -1,48, 2,12). Conclusión: el uso de probióticos en pacientes con asma puede mejorar la inflamación pulmonar y los síntomas del asma, reducir el número de ataques de asma y no tener efecto sobre la función pulmonar.(AU)

A High Docosahexaenoic Acid Diet Alters the Lung Inflammatory Response to Acute Dust Exposure.

Agricultural workers are at risk for the development of acute and chronic lung diseases due to their exposure to organic agricultural dusts. A diet intervention using the omega-3 fatty acid docosahexaenoic acid (DHA) has been shown to be an effective therapeutic approach for alleviating a dust-induced inflammatory response. We thus hypothesized a high-DHA diet would alter the dust-induced inflammatory response through the increased production of specialized pro-resolving mediators (SPMs). Mice were pre-treated with a DHA-rich diet 4 weeks before being intranasally challenged with a single dose of an extract made from dust collected from a concentrated swine feeding operation (HDE). This omega-3-fatty-acid-rich diet led to reduced arachidonic acid levels in the blood, enhanced macrophage recruitment, and increased the production of the DHA-derived SPM Resolvin D1 (RvD1) in the lung following HDE exposure. An assessment of transcript-level changes in the immune response demonstrated significant differences in immune pathway activation and alterations of numerous macrophage-associated genes among HDE-challenged mice fed a high DHA diet. Our data indicate that consuming a DHA-rich diet leads to the enhanced production of SPMs during an acute inflammatory challenge to dust, supporting a role for dietary DHA supplementation as a potential therapeutic strategy for reducing dust-induced lung inflammation.

Impact of Multiple Texture-Modified Diets on Oral Intake and Nutritional Status in Older Patients with Pneumonia: A Retrospective Cohort Study.

Texture-modified diets (TMD) is often used in clinical practices for the treatment and prevention of pneumonia. However, it is unclear how stages of TMD affect the swallowing ability and nutritional status in patients with pneumonia. This study aimed to investigate the relationship between the various stages of TMD and swallowing ability and nutritional status in older inpatients with pneumonia. In this retrospective cohort study, data for patients aged ≥ 65 years with pneumonia were obtained from the Japan Rehabilitation Nutrition Database. We performed coarsened exact matching with Mini Nutritional Assessment Short Form (MNA-SF) on admission. Ultimately, 218 patients (mean age 82.9 ± 9.8 years) were included and divided into two groups based on the stages of TMD in the facility: multiple TMD (M-TMD) group (stages of TMD ≥ 6) and control group (stages of TMD < 6). The main outcome was the rate of improvement in the Food Intake Level Scale (FILS) and the maintenance or improvement in the MNA-SF score. We used the within-hospital correction with generalized estimation equations that are commonly used to analyze clustered data while correcting for confounding factors by clustering. Multivariate multiple logistic analysis showed that M-TMD was independently associated with FILS improvement rate and the maintenance or improvement in the MNA-SF score (odds ratio [OR] 3.252; 95% confidence interval [CI] 1.602-6.601; p = 0.001 and OR 1.873; 95% CI 1.054-3.330; p = 0.032, respectively). M-TMD in the facility was associated with the maintenance or improvement in swallowing ability and the nutritional status of patients with pneumonia.

Vitamin D supplementation in respiratory diseases: evidence from randomized controlled trials.

Pulmonary diseases are one of the most important causes of morbidity and mortality. Although vitamin D is best known for its role in calcium, phosphorus, and bone homeostasis, it has gained attention in the recent years because of a wide range of extraskeletal effects, including its immunomodulatory and antibacterial potential. Vitamin D deficiency is highly prevalent in chronic pulmonary diseases such as chronic obstructive pulmonary disease (COPD), cystic fibrosis, tuberculosis, and asthma, and several clinical studies have been conducted investigating the effect of vitamin D supplementation on disease outcomes. In this review, we searched for positive evidence on vitamin D supplementation from randomized controlled trials and elaborated on the optimal serum vitamin D levels and dosing regimens for an effective intervention. While vitamin D supplementation seems to be beneficial as an add­on treatment for adult patients with asthma and a potent intervention to reduce exacerbations in patients with COPD, there is little evidence for its therapeutic use in cystic fibrosis, pneumonia, and tuberculosis.

Effect of an injectable trace mineral supplement containing selenium, copper, zinc, and manganese on immunity, health, and growth of dairy calves.

The objective of this study was to evaluate the effect of 2 subcutaneous injections of a multimineral preparation, each containing 60 mg of zinc, 10mg of manganese, 5mg of selenium, and 15 mg of copper at 3 and 30 d after birth on immunity, health, and growth of dairy calves during the preweaning period. The study was conducted in upstate New York in 2 commercial dairy farms. A total of 790 Holstein heifer calves were randomly allocated at birth into 1 of 2 treatments: trace mineral supplement (TMS) treated or control. Blood samples were collected at 3, 14, and 35 d after birth to evaluate glutathione peroxidase (GPx) activity, superoxide dismutase (SOD) activity, haptoglobin, and neutrophil and monocyte function. Incidence of diseases and average daily gain was evaluated in the first 50 d of life. At 14 d of life, TMS-treated calves had increased neutrophil activity compared with control calves. Moreover, TMS-treated calves had greater GPx activity on d 14 after birth than control calves. The TMS treatment reduced the incidence of diarrhea (TMS=41.7% vs. control=49.7%) and combined incidence of pneumonia or otitis or both (TMS=41.7% vs. control=49.1%). Additionally, GPx was greater for calves diagnosed with otitis at d 35 after birth. However, calves diagnosed with pneumonia had decreased GPx activity at d 35 after birth. Serum SOD and haptoglobin concentrations were not affected by treatment or disease. Moreover, no effects were observed on average daily gain and survivability between TMS-treated and control calves during the preweaning period. Supplementation with trace minerals at 3 and 30 d of life increased neutrophil function and GPx activity and reduced the incidence of health disorders.

Zinc as an adjunct to the treatment of severe pneumonia in Ecuadorian children: a randomized controlled trial.

BACKGROUND: Studies of zinc as an adjunct to treatment of severe pneumonia in children have shown mixed results, possibly because of poor information on zinc status and respiratory pathogens. OBJECTIVE: We evaluated the effect of zinc given with standard antimicrobial treatment on the duration of respiratory signs in children with severe pneumonia. Zinc status and pathogens were assessed. DESIGN: Children aged 2-59 mo with severe pneumonia who were admitted to the main children's hospital in Quito, Ecuador, were given standard antibiotics and randomly allocated to receive zinc supplements twice daily or a placebo. Measurements included anthropometric variables, breastfeeding, hemoglobin, plasma zinc, and common bacteria/viral respiratory pathogens. The primary outcome was time to resolution of respiratory signs. The secondary outcome was treatment failure. RESULTS: We enrolled 225 children in each group. There was no difference between groups in time to resolution of respiratory signs or treatment failure; pathogens were not associated with outcomes. Tachypnea and hypoxemia resolved faster in older children (P = 0.0001) than in younger ones. Higher basal zinc concentration (P = 0.011) and better height-for-age z score (HAZ) (P = 0.044) were associated with faster resolution of chest indrawing. Better weight-for-height z score (WHZ) (P = 0.031) and HAZ (P = 0.048) were associated with faster resolution of tachypnea. Increased C-reactive protein was associated with a longer duration of tachypnea (P = 0.044). CONCLUSIONS: Zinc did not affect time to pneumonia resolution or treatment failure, nor did type of respiratory pathogens affect outcomes. Higher basal zinc and better HAZ and WHZ were associated with reduced time to resolution of respiratory signs. These results suggest the need for prevention of chronic zinc deficiency and improvement of general nutritional status among Ecuadorian children.

Effects of zinc supplementation on the incidence of mortality in preschool children: a meta-analysis of randomized controlled trials.

BACKGROUND: Previous trials have shown that zinc supplementation can decrease the risk of diarrhea, pneumonia, and malaria in children; however, the effects of zinc supplementation on mortality remain unclear. This study aimed at evaluating the benefits and risks of zinc supplementation on both total mortality and cause-specific mortality. METHODOLOGY AND PRINCIPAL FINDINGS: We searched PubMed, EmBase, and the Cochrane Central Register of Controlled Trials to identify randomized controlled trials in preschool children reporting total mortality or cause-specific mortality. Relative risk (RR) was used as a measure of the effect of zinc supplementation on the risk of mortality using a random effect model. Of the 1,520 identified articles, we included 8 trials reporting data on 87,854 children. Overall, zinc supplementation had no effect on total mortality (RR, 0.76; 95% CI: 0.56-1.04; P = 0.084), diarrhea-related mortality (RR, 0.80; 95% CI: 0.53-1.20; P = 0.276), pneumonia-related mortality (RR, 0.52; 95% CI: 0.11-2.39; P = 0.399), malaria-related mortality (RR, 0.90; 95% CI: 0.77-1.06; P = 0.196), or other causes of mortality (RR, 0.98; 95% CI: 0.67-1.44; P = 0.917). Subgroup analysis indicated that zinc supplementation was associated with a reduction in total mortality risk if the participants were boys, aged greater than 12 months, and the duration of the follow-up period was less than 12 months. CONCLUSIONS/SIGNIFICANCE: Zinc supplementation does not have an effect on total mortality, diarrhea-related mortality, pneumonia-related mortality, malaria-related mortality, or other causes of mortality. Subgroup analysis suggested that zinc supplementation can effectively reduce the risk of total mortality if the participants were boys, aged greater than 12 months, and the duration of the follow-up period was less than 12 months.

Dietary supplementation with omega-3 polyunsaturated fatty acids ameliorates acute pneumonia induced by Klebsiella pneumoniae in BALB/c mice.

The immune benefits associated with the optimal intake of dietary fatty acids are widely known. The objective of the present investigation was to elucidate the role of omega-3 polyunsaturated fatty acids (n-3 PUFA) food source on acute pneumonia induced by Klebsiella pneumoniae. Three different n-3 PUFA preparations (cod liver oil, Maxigard, and flaxseed oil) were orally supplemented and infection was induced in different groups of experimental mice. Mice fed olive oil and normal saline served as oil and saline controls, respectively. After 2 weeks of fatty acid feeding, no effect on the establishment of infection was observed when acute pneumonia was induced in animals. On the other hand, 6 weeks of n-3 PUFA administration was found to improve resistance in mice, as reduced lung bacterial load coupled with significant improvement in pathology was seen in infected mice. Alveolar macrophages collected from all 3 groups of mice fed n-3 PUFA exhibited a significant decrease in the level of apoptosis following infection with K. pneumoniae and an enhanced in vitro phagocytic potential for the pathogen. Lower lung levels of nitric oxide, malondialdehyde, and lactate dehydrogenase were associated with a decrease in the severity of tissue damage. There was a significant increase in the lung levels of pro-inflammatory cytokines (tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1ß)). No significant change was observed in the levels of interleukin-10 (IL-10). This study highlights that dietary n-3 PUFA supplementation exerts an overall beneficial effect against acute experimental pneumonia. This mechanism is operative through upregulation of nonspecific and specific immune defenses of the host.

In vitro and in vivo properties of a fully human IgG1 monoclonal antibody that combats multidrug resistant Pseudomonas aeruginosa.

The development of an anti-bacterial drug in the form of a monoclonal antibody (mAb) targeting an exposed virulence factor, represents an innovative therapeutic strategy. Consequently, a fully human IgG1 mAb (LST-007) targeting Pseudomonas aeruginosa (PA) flagellin type b was recombinantly expressed and characterized in vitro and in an infection model driven by a multidrug resistant (MDR) PA strain. LST-007 demonstrated a highly specific binding towards whole PA bacteria harboring flagellin type b and its recombinant counterpart, with a K(D) of 7.4x10(-10) M. In bioactivity assays, LST-007 or titers of Cmax sera derived from pharmacokinetic studies, markedly attenuated PA motility in an equipotent manner. In vivo, parenteral LST-007 (20 mg/kg) given as a single or double-dosing paradigm post-infection, afforded survival (up to 75% at Day 7) in a lethal model of pneumonia driven by the intratracheal (i.t.) instillation of an LD(80) of the MDR PA isolate. This protective effect was markedly superior to that of imipenem (30% survival at Day 7) and totally devoid with an irrelevant, human isotype mAb. These data lay credence that LST-007 may be a valuable adjunct to the limited list of anti-bacterials that can tackle MDR PA strains, thereby warranting its continued development for eventual clinical evaluation.

Dietary flaxseed protects against lung ischemia reperfusion injury via inhibition of apoptosis and inflammation in a murine model.

BACKGROUND: The hallmark of lung ischemia-reperfusion injury (IRI) is the production of reactive oxygen species (ROS), and the resultant oxidant stress has been implicated in apoptotic cell death as well as subsequent development of inflammation. Dietary flaxseed (FS) is a rich source of naturally occurring antioxidants and has been shown to reduce lung IRI in mice. However, the mechanisms underlying the protective effects of FS in IRI remain to be determined. METHODS: We used a mouse model of IRI with 60 min of ischemia followed by 180 min of reperfusion and evaluated the anti-apoptotic and anti-inflammatory effects of 10% FS dietary supplementation. RESULTS: Mice fed 10% FS undergoing lung IRI had significantly lower levels of caspases and decreased apoptotic activity compared with mice fed 0% FS. Lung homogenates and bronchoalveolar lavage fluid analysis demonstrated significantly reduced inflammatory infiltrate in mice fed with 10% FS diet. Additionally, 10% FS treated mice showed significantly increased expression of antioxidant enzymes and decreased markers of lung injury. CONCLUSIONS: We conclude that dietary FS is protective against lung IRI in a clinically relevant murine model, and this protective effect may in part be mediated by the inhibition of apoptosis and inflammation.

Effect of multiple micronutrient-fortified food on mild morbidity and clinical symptoms in Zambian infants: results from a randomised controlled trial.

BACKGROUND/OBJECTIVES: We aimed to assess the effects on mild morbidity of a richly micronutrient-fortified complementary/replacement food given to Zambian infants aged 6-18 months. Previous results (The Chilenje Infant Growth, Nutrition and Infection Study Team, 2010) showed an increase in the rate of hospital referral for pneumonia in the same cohort. SUBJECT/METHODS: A total of 743 six-month-old healthy Zambian infants were randomised to receive either a richly or a basal micronutrient-fortified porridge for 12 months. Mild morbidity was defined as an illness that did not cause death or require hospitalisation and was diagnosed on clinical examination at scheduled visits. RESULTS: There was no evidence of an effect of trial arm on overall mild morbidity during the study (odds ratio (OR)=1.04, 95% confidence interval (CI)=0.90, 1.20, P=0.62). Infants in the richly fortified arm had significantly more visits in which they were diagnosed with lower respiratory tract infections/pneumonia (OR=1.65, 95% CI=1.06, 2.59, P=0.03) and fewer visits in which a diagnosis of urinary tract infection was made (OR=0.43, 95% CI=0.21, 0.87, P=0.02). Maternally reported symptoms were similar between trial arms. CONCLUSION: Compared with the basal diet, the richly micronutrient-fortified food was associated with more episodes of lower respiratory infections/pneumonia diagnosed at scheduled visits, which reinforces our previously reported findings of a higher incidence in hospital referral for pneumonia.

Dietary supplementation of omega-3 fatty acid-containing fish oil suppresses F2-isoprostanes but enhances inflammatory cytokine response in a mouse model of ovalbumin-induced allergic lung inflammation.

Epidemiological and clinical evidence has suggested that increased dietary intake of fish oil containing omega-3 fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) may be associated with a reduced risk of asthma. However, interventional studies on these effects have been equivocal and controversial. Free radical oxidation products of lipids and cyclooxygenases-derived prostaglandins are believed to play an important role in asthma, and fish oil supplementation may modulate the levels of these critical lipid mediators. We employed a murine model of allergic inflammation produced by sensitization to ovalbumin (OVA) to study the effects of fish oil supplementation on airway inflammation. Our studies demonstrated that omega-3 fatty acids were dose dependently incorporated into mouse lung tissue after dietary supplementation. We examined the oxidative stress status by measuring the levels of isoprostanes (IsoPs), the gold standard for oxidative stress in vivo. OVA challenge caused significant increase of F(2)-IsoPs in mouse lung, suggesting an elevated level of oxidative stress. Compared to the control group, fish oil supplementation led to a significant reduction of F(2)-IsoP (from arachidonic acid) with a concomitant increase of F(3)-IsoPs (from EPA) and F(4)-IsoPs (from DHA). Surprisingly, however, fish oil supplementation enhanced production of proinflammatory cytokine IL-5 and IL-13. Furthermore, fish oil supplementation suppressed the production of pulmonary protective PGE(2) in the bronchoalveolar lavage (BAL) while the level of urinary metabolites of the PGE(2) was increased. Our data suggest that augmented lung inflammation after fish oil supplementation may be due to the reduction of PGE(2) production in the lung and these dichotomous results bring into question the role of fish oil supplementation in the treatment of asthma.

Dietary tryptophan helps to preserve tryptophan homeostasis in pigs suffering from lung inflammation.

In pigs, inflammation modifies Trp metabolism and consequently could impact on Trp requirement for growth. In this study, the effects of lung inflammation, induced by the intravenous injection of complete Freund's adjuvant, and dietary Trp content on Trp metabolism and availability were investigated. Two dietary Trp contents, one corresponding to a low-Trp diet (1.5 g of Trp/kg of diet, Basal diet) and the second to an adequate-Trp diet (2 g of Trp/kg of diet, TRP diet), were used. Ten blocks of 4 littermate piglets were selected at 40 d of age. Within each block, piglets were randomly assigned to 1 of the 4 experimental treatments: (1) healthy control and Basal diet, (2) inflammation and Basal diet, (3) inflammation and Basal diet + antioxidant, and (4) inflammation and TRP diet. Inflammation induced an increase in indoleam-ine 2,3 dioxygenase (IDO) activity, an enzyme involved in Trp catabolism, in lung, lymph nodes, heart, and spleen (P < 0.01). Contrary to piglets fed the TRP diet, pigs suffering from inflammation did not maintain their plasma Trp concentrations when they were fed the Basal diet. Furthermore, pigs fed the TRP diet had decreased plasma haptoglobin concentrations, IDO activity, and lung weight than those fed the Basal diet, indicating that the inflammatory response was moderated with the greater Trp supply. Antioxidant addition in the Basal diet decreased the effects of inflammation on plasma Trp concentrations and IDO activity. These results indicated that inflammation increases Trp catabolism and thus may decrease Trp availability for growth.

[Effect of nutrient support on severe infant pneumonia].

OBJECTIVE: To explore the effect of nutrient support on severe infant pneumonia. METHODS: Prospective study was conducted on the outcome of 567 inpatients suffering from severe pneumonia in 13 hospitals randomly selected in Hunan. Twelve factors were surveyed and data analyzed by multiple logistic regression. RESULTS: Malnnutrition, anemia and rickets were risk factors in severe pneumonia, and nutrient support had protective effect on severe pneumonia. CONCLUSION: Nutrient support contributes to the positive outcome of severe infant pneumonia.

[Correction of selenium deficiency in patients with pneumonia]. / Korrektsiia nedostatochnosti selena u bol'nykh pnevmoniei.

The estimation of selenium (Se) safety in patients with pneumonia is important for evaluation of antioxidant defense system capacity and the immune status of the patients. The research has been carried out on the serum Se levels in patients with pneumonia at standard treatment and at treatment with the usage of selenium enriched food supplement (Se-spirulina). The results of research have shown that application of additional selenium in amount providing physiological requirement leads to full varnishing its deficiency cases and to restoration in the majority of patients the suboptimum Se level.

A case of cough, lymphocytic bronchoalveolitis and coeliac disease with improvement following a gluten free diet.

Chronic cough is a common reason for presentation to a respiratory clinic. In up to 20% of cases the cause remains unclear after investigations. We report one such case where there was bronchoscopic evidence of lymphocytic airway inflammation in association with newly diagnosed coeliac disease. All features improved markedly on a gluten free diet, suggesting a causal relationship between coeliac disease, cough, and lymphocytic bronchoalveolitis.

[Use of SGOL-1-40 milk whey in the complex therapy of patients with acute chemical poisoning and burns of the gastrointestinal tract]. / Ispol'zovanie molochnoi fermentirovannoi syvorotki SGOL-1-40 v kompleksnom lechenii ostrykh khimicheskikh boleznei i ozhogov zheludochno-kishechnogo trakta.

The use of "SGOL-1-40" milk whey in complex therapy of patients with acute chemical poisonings and their complications has been investigated. "SGOL-1-40" was prescribed twice per day with the dose of 1.5 g/kg of patient weight. On the 5th-6th day after therapy start the general state of patients improved; in the control group it happened on the 10th-12th day. It is ascertained that the ceasing of pneumonia takes place average 3 days earlier than usual. The lessening of endotoxicosis symptoms and the improvement of the patients state with chemical burns of gastrointestinal system went on more quickly.

Influencia del entorno ambiental y tipo de régimen dietético en la incidencia, duración e intensidad de los procesos infecciosos del lactante / The role of environmental factors and type of dietary regimen on morbidity in young infants

Objetivo. Estudiar las enfermedades infecciosas y su relación con el entorno ambiental en lactantes, desde su nacimiento hasta los 4 meses de edad. Material y Métodos. Han intervenido más de 600 pediatras. Se incluyó a niños de hasta 20 días que fueron reevaluados cuando tenían 4 meses, para estudiar las complicaciones infecciosas aparecidas. Análisis estadístico mediante regresión logística. Resultados. Se incluyeron 3.428 niños a término. Las infecciones oftálmicas fueron las más frecuentes (5,5 por ciento). Las bronquitis y neumonías las más graves (61 por ciento moderadas-graves) y de mayor duración (6,5 ñ 3 días). La polución, entorno fumador y convivencia con hermanos constituyen factores de riesgo. A los 4 meses, la administración de una fórmula sin nucleótidos se añadió a los factores de riesgo previos. Conclusiones. El entorno ambiental es importante en la incidencia de enfermedades infecciosas en el lactante. El riesgo aumenta por: asistencia a guarderías, polución y ambiente fumador. La alimentación con leche materna y una fórmula con nucleótidos son favorables para el desarrollo inmunológico de los lactantes. (AU)