RESUMEN
OBJECTIVES: Eosinophilic esophagitis (EoE) represents a chronic, immune/antigen-mediated esophageal disease characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation. With few exceptions, 15 eosinophils per high-power field (peak value) in ≥1 biopsy specimens are considered a minimum threshold for a diagnosis of EoE. The disease is restricted to the esophagus, and other causes of esophageal eosinophilia should be excluded, specifically proton pump inhibitor-responsive esophageal eosinophilia. This position paper aims at providing practical guidelines for the management of children and adolescents with EoE. METHODS: Relevant literature from searches of PubMed, CINAHL, and recent guidelines was reviewed. In the absence of an evidence base, recommendations reflect the expert opinion of the authors. Final consensus was obtained during 3 face-to-face meetings of the Gastroenterology Committee and 1 teleconference. RESULTS: The cornerstone of treatment is an elimination diet (targeted or empiric elimination diet, amino acid-based formula) and/or swallowed, topical corticosteroids. Systemic corticosteroids are reserved for severe symptoms requiring rapid relief or where other treatments have failed. Esophageal dilatation is an option in children with EoE who have esophageal stenosis unresponsive to drug therapy. Maintenance treatment may be required in case of frequent relapse, although an optimal regimen still needs to be determined. CONCLUSIONS: EoE is a chronic, relapsing inflammatory disease with largely unquantified long-term consequences. Investigations and treatment are tailored to the individual and must not create more morbidity for the patient and family than the disease itself. Better maintenance treatment as well as biomarkers for assessing treatment response and predicting long-term complications is urgently needed.
Asunto(s)
Esofagitis Eosinofílica/terapia , Eosinófilos , Esófago/patología , Corticoesteroides/uso terapéutico , Niño , Consenso , Esofagitis Eosinofílica/complicaciones , Esofagitis Eosinofílica/dietoterapia , Esofagitis Eosinofílica/tratamiento farmacológico , Estenosis Esofágica/etiología , Estenosis Esofágica/terapia , Humanos , RecurrenciaRESUMEN
OBJECTIVE: To systematically review the evidence base for the medical (pharmaceutical and nutritional) treatment of paediatric inflammatory bowel disease. METHODS: Key clinical questions were formulated regarding different treatment modalities used in the treatment of paediatric (not adult-onset) IBD, in particular the induction and maintenance of remission in Crohn disease and ulcerative colitis. Electronic searches were performed from January 1966 to December 2006, using the electronic search strategy of the Cochrane IBD group. Details of papers were entered on a dedicated database, reviewed in abstract form, and disseminated in full for appraisal. Clinical guidelines were appraised using the AGREE instrument and all other relevant papers were appraised using Scottish Intercollegiate Guidelines Network methodology, with evidence levels given to all papers. RESULTS: A total of 6285 papers were identified, of which 1255 involved children; these were entered on the database. After critical appraisal, only 103 publications met our criteria as evidence on medical treatment of paediatric IBD. We identified 3 clinical guidelines, 1 systematic review, and 16 randomised controlled trials; all were of variable quality, with none getting the highest methodological scores. CONCLUSIONS: This is the first comprehensive review of the evidence base for the treatment of paediatric IBD, highlighting the paucity of trials of high methodological quality. As a result, the development of clinical guidelines for managing children and young people with IBD must be consensus based, informed by the best-available evidence from the paediatric literature and high-quality data from the adult IBD literature, together with the clinical expertise and multidisciplinary experience of paediatric IBD experts.
Asunto(s)
Corticoesteroides/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Factores Inmunológicos/uso terapéutico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Adolescente , Corticoesteroides/efectos adversos , Antiinflamatorios no Esteroideos/efectos adversos , Huesos/efectos de los fármacos , Niño , Humanos , Factores Inmunológicos/efectos adversos , Enfermedades Inflamatorias del Intestino/dietoterapia , Quimioterapia de Mantención , Mesalamina/uso terapéutico , Inducción de Remisión , Sulfasalazina/uso terapéuticoRESUMEN
BACKGROUND: The breakdown of glycosaminoglycans is an important consequence of inflammation at mucosal surfaces, and inhibition of metalloprotease activity may be effective in treating chronic inflammation. AIM: To report an alternative approach, using the nutriceutical agent N-acetyl glucosamine (GlcNAc), an amino-sugar directly incorporated into glycosaminoglycans and glycoproteins, as a substrate for tissue repair mechanisms. METHODS: GlcNAc (total daily dose 3-6 g) was administered orally as adjunct therapy to 12 children with severe treatment-resistant inflammatory bowel disease (10 Crohn's disease, 2 ulcerative colitis). Seven of these children suffered from symptomatic strictures. In addition, similar doses were administered rectally as sole therapy in nine children with distal ulcerative colitis or proctitis resistant to steroids and antibiotics. Where pre- and post-treatment biopsies were available (nine cases), histochemical assessment of epithelial and matrix glycosaminoglycans and GlcNAc residues was made. FINDINGS: Eight of the children given oral GlcNAc showed clear improvement, while four required resection. Of the children with symptomatic Crohn's stricture, only 3 of 7 have required surgery over a mean follow-up of > 2.5 years, and endoscopic or radiological improvement was detected in the others. Rectal administration induced remission in two cases, clear improvement in three and no effect in two. In all cases biopsied there was evidence of histological improvement, and a significant increase in epithelial and lamina propria glycosaminoglycans and intracellular GlcNAc. CONCLUSIONS: GlcNAc shows promise as an inexpensive and nontoxic treatment in chronic inflammatory bowel disease, with a mode of action which is distinct from conventional treatments. It may have the potential to be helpful in stricturing disease. However, controlled trials and an assessment of enteric-release preparations are required to confirm its efficacy and establish indications for use.
Asunto(s)
Acetilglucosamina/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Glicosaminoglicanos/biosíntesis , Acetilglucosamina/administración & dosificación , Administración Oral , Administración Rectal , Adolescente , Corticoesteroides/uso terapéutico , Niño , Enfermedad Crónica , Femenino , Humanos , Masculino , Proyectos PilotoRESUMEN
There is growing awareness that primary gastrointestinal pathology may play an important role in the inception and clinical expression of some childhood developmental disorders, including autism. In addition to frequent gastrointestinal symptoms, children with autism often manifest complex biochemical and immunological abnormalities. The gut-brain axis is central to certain encephalopathies of extra-cranial origin, hepatic encephalopathy being the best characterized. Commonalities in the clinical characteristics of hepatic encephalopathy and a form of autism associated with developmental regression in an apparently previously normal child, accompanied by immune-mediated gastrointestinal pathology, have led to the proposal that there may be analogous mechanisms of toxic encephalopathy in patients with liver failure and some children with autism. Aberrations in opioid biochemistry are common to these two conditions, and there is evidence that opioid peptides may mediate certain aspects of the respective syndromes. The generation of plausible and testable hypotheses in this area may help to identify new treatment options in encephalopathies of extra-cranial origin. Therapeutic targets for this autistic phenotype may include: modification of diet and entero-colonic microbial milieu in order to reduce toxin substrates, improve nutritional status and modify mucosal immunity; anti-inflammatory/immunomodulatory therapy; and specific treatment of dysmotility, focusing, for example, on the pharmacology of local opioid activity in the gut.
Asunto(s)
Trastorno Autístico/etiología , Enfermedad Celíaca/complicaciones , Encefalopatía Hepática/complicaciones , Neuroinmunomodulación , Receptores Opioides/metabolismo , Trastorno Autístico/inmunología , Trastorno Autístico/metabolismo , Barrera Hematoencefálica/inmunología , Enfermedad Celíaca/inmunología , Enfermedad Celíaca/metabolismo , Niño , Encefalopatía Hepática/inmunología , Encefalopatía Hepática/metabolismo , Humanos , Inmunidad Mucosa/inmunología , Absorción Intestinal/inmunología , Ligandos , Péptidos Opioides/inmunología , Péptidos Opioides/metabolismo , Receptores Opioides/inmunologíaRESUMEN
BACKGROUND: Azathioprine is widely used as maintenance therapy in children with moderate to severe inflammatory bowel disease (IBD). There is no data on safety at higher doses and its impact on growth and surgical morbidity in children. METHODS: This retrospective cohort study included all children treated with azathioprine and diagnosed with IBD between 1996-2001. Outcome measures included indications for azathioprine use, adverse-effects and reasons for treatment discontinuation. Height and weight at diagnosis, treatment onset and current follow-up was recorded, and Z scores for height standardised for time. RESULTS: 107 children received azathioprine at 3 mg/kg. 61% had Crohn's disease and 83% started azathioprine within 2 years of diagnosis. Only 2/107 children had to stop azathioprine because of persistent adverse effects and 16/107 required surgery. There was a trend toward better growth in a group of children with Crohn's disease following treatment with high dose azathioprine therapy (P = 0.08). CONCLUSIONS: Azathioprine is a safe and well-tolerated maintenance therapy at 3 mg/kg for children with IBD. The prevalence of surgery and growth failure in a cohort of children with moderate to severe IBD appears less than previously reported. In children with Crohn's disease, growth velocity may be maximised by an emphasis on nutritional therapy and the use of high dose azathioprine.
Asunto(s)
Azatioprina/administración & dosificación , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Administración Oral , Adolescente , Azatioprina/efectos adversos , Niño , Preescolar , Estudios de Cohortes , Estudios de Seguimiento , Crecimiento/efectos de los fármacos , Humanos , Lactante , Modelos Logísticos , Estudios RetrospectivosRESUMEN
BACKGROUND: The management of acute fulminant colitis unresponsive to intravenous steroids is usually surgical. However, recent evidence suggests that intravenous administration of azathioprine at very high doses may allow more rapid onset of clinical efficacy, although its use has not previously been reported in the emergency situation. AIM: To report the successful use of intravenous azathioprine in the management of acute fulminant colitis complicating both Crohn's disease and ulcerative colitis. METHOD: We initially used intravenous azathioprine because of the refusal of the family of the first patient to accept surgery following failure of conventional medical management. Importantly the azathioprine was successful at the low dose of 3 mg/kg.day, equivalent to standard oral doses. Two subsequent patients demonstrated a similar resolution. All were weaned successfully to oral azathioprine and have remained in long-term endoscopic and histological remission. CONCLUSION: These preliminary data suggest that low-dose intravenous azathioprine may be helpful adjunct therapy in selected cases of severe fulminant colitis. However, the need for close monitoring and daily surgical assessment remains paramount, and a formal trial of low-dose intravenous azathioprine is required before it may be more widely recommended.
Asunto(s)
Azatioprina/administración & dosificación , Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Enfermedad Aguda , Adolescente , Niño , Colitis Ulcerosa/complicaciones , Enfermedad de Crohn/complicaciones , Esquema de Medicación , Femenino , Humanos , Inyecciones Intravenosas , MasculinoRESUMEN
In the intestine large numbers of bacteria and their products are separated by a single epithelial layer from resident inflammatory cells (macrophages and lymphocytes). Many of these bacterial products, such as lipopolysaccharides and peptidoglycans, are potent stimulators of free radical and inflammatory cytokine production by macrophages. This can occur in vivo in response to mucosal invasion by enteropathogenic bacteria or because of inappropriate activation of these cells, as in chronic inflammatory bowel disease. In this review we present evidence for production of cytokines in normal intestine and in intestinal inflammatory conditions. The adverse effects of cytokine production upon intestinal homeostasis, in particular disruption of epithelial integrity and prothrombotic changes in the vascular endothelium, are also discussed.
Asunto(s)
Citocinas/fisiología , Diarrea/inmunología , Enfermedades Inflamatorias del Intestino/inmunología , Intestinos/inmunología , Endotelio Vascular/metabolismo , Humanos , Interleucina-6/biosíntesis , Mucosa Intestinal/inmunología , Macrófagos/inmunología , Factor de Necrosis Tumoral alfa/biosíntesisRESUMEN
Mucosal macrophages and accessory cells have been studied by immunohistochemistry in the lamina propria of the colon of children with Trichuris trichiura dysentery syndrome (TDS). No difference was found in the numbers of cells recognized by the monoclonal antibodies CD11c, CD68, or RFD7 between TDS children and local controls. However, large numbers of cells were recognized by an antibody against calprotectin (an anti-bacterial glycoprotein found in tissue infiltrating-monocytes) in TDS colonic mucosa, but few in control colon. Large numbers of cells containing tumour necrosis factor alpha (TNF alpha) were also seen in TDS mucosa; cells isolated from TDS mucosa secreted more TNF alpha than cells from control mucosa; and children with TDS had high levels of circulating TNF alpha. Non-specific macrophage-mediated inflammation and local cytokine production may therefore play a role in the pathogenesis of TDS.
Asunto(s)
Enfermedades del Colon/inmunología , Disentería/parasitología , Parasitosis Intestinales/inmunología , Tricuriasis/inmunología , Factor de Necrosis Tumoral alfa/metabolismo , Niño , Preescolar , Colon/inmunología , Humanos , Inmunidad Celular , Inmunohistoquímica , Lactante , Mucosa Intestinal/inmunología , Macrófagos/inmunologíaRESUMEN
There is increasing recognition of childhood enteropathies that are distinct from classic conditions, such as celiac disease. In several cases, an underlying molecular basis has not been determined. The findings at endoscopy and routine histopathology, however, may be nonspecific in many cases. This article focuses on the specific diagnostic features and underlying pathophysiology of these uncommon and challenging conditions.
Asunto(s)
Diarrea Infantil/patología , Endoscopía Gastrointestinal/métodos , Enterocolitis/patología , Mucosa Intestinal/patología , Enfermedad Aguda , Adolescente , Biopsia con Aguja , Niño , Preescolar , Enfermedad Crónica , Diagnóstico Diferencial , Diarrea Infantil/diagnóstico , Enterocolitis/diagnóstico , Femenino , Humanos , Lactante , Mucosa Intestinal/microbiología , Masculino , Factores de Riesgo , Sensibilidad y EspecificidadRESUMEN
The activation of macrophages and newly recruited monocytes appears to be common to both Crohn's disease and ulcerative colitis, despite different inductive stimuli. Similar activation occurs acutely during the course of invasive intestinal infections such as shigellosis, but is then usually downregulated. The macrophage cytokines tumor necrosis factor-alpha and interleukin-1 (IL-1) are centrally involved in the local inflammatory response, and blockade of either cytokine greatly attenuates the inflammatory lesion. Induction of focal vascular thrombosis and matrix degradation are thought to be an important component of this focal damage. Both cytokines and IL-6 are now recognized to contribute to the systemic effects of intestinal disease, including growth suppression, anorexia, and chronic anemia. Disturbance of sleep patterns, mood, and affect may also occur, and recent evidence points towards bidirectional interplay between macrophage cytokines and central nervous system function.
Asunto(s)
Citocinas/fisiología , Enfermedades Inflamatorias del Intestino/fisiopatología , Macrófagos/metabolismo , Colitis Ulcerosa/fisiopatología , Enfermedad de Crohn/fisiopatología , Humanos , Interleucina-1/fisiología , Activación de Macrófagos , Sistema Nervioso/fisiopatología , Factor de Necrosis Tumoral alfa/fisiologíaRESUMEN
Kawasaki disease (mucocutaneous lymph node syndrome) is an acute vasculitis of childhood carrying a 1-2 per cent mortality from cardiovascular complications. Despite the extensive literature on Kawasaki disease in paediatric journals, there has been a paucity of documentation in the otolaryngology literature. This is despite the fact that Kawasaki disease may present as an otolaryngological emergency before the diagnosis is established. We describe three cases of Kawasaki disease, all of which presented to the ENT department of this hospital within a period of two months. These cases illustrate the slow evolution characteristic of the disease and highlight the difficulties of diagnosis in the initial febrile stage. We emphasize the importance of considering the diagnosis when treating a young child with a pyrexia resistant to antibiotics, as prompt introduction of therapy may decrease the risk of fatal coronary artery or cardiac involvement.
Asunto(s)
Síndrome Mucocutáneo Linfonodular/diagnóstico , Enfermedades Otorrinolaringológicas/diagnóstico , Enfermedad Aguda , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Factores de TiempoRESUMEN
BACKGROUND: Human ex vivo evidence indicating that an inappropriate immune response(s) to nonpathogenic bacteria contributes to disease pathogenesis in pediatric Crohn's disease (CD) is limited. The aim of the present study was to compare and contrast the early innate immune response of pediatric "healthy" versus CD mucosa to pathogenic, probiotic, and commensal bacteria. METHODS: "Healthy control" and CD pediatric mucosal biopsies (terminal ileum and transverse colon) were cocultured for 8 hours with E. coli O42, Lactobacillus GG (LGG), Bacteroidesthetaiotaomicron (B. theta), or stimulated with interleukin (IL)-1ß (positive control). Matched nonstimulated biopsies served as experimental controls. IL-8 was the immune marker of choice. IL-8 mRNA and protein levels were quantified by quantitative polymerase chain reaction and sandwich enzyme-linked immunosorbent assay, respectively. RESULTS: IL-8 secretion was observed when control, ileal biopsies were exposed to pathogenic O42 and probiotic LGG, with no response noted to commensal B. theta. In comparison, Crohn's ileal biopsies showed impaired ability to induce IL-8 in response to O42 and LGG. Control colonic tissue showed a limited response to O42 or B. theta and LGG significantly reduced IL-8 secretion. Unlike control tissue, however, Crohn's ileal and colonic tissue did respond to B. theta, with more enhanced expression in the colon. CONCLUSIONS: We provide the first ex vivo data to support the notion that aberrant mucosal recognition of commensal bacteria may contribute to pediatric CD. While IL-8 responses to O42 and LGG varied with disease status and anatomical location, B. theta consistently induced significant IL-8 both in ileal and colonic CD tissue, which was not seen in control, healthy tissue.
Asunto(s)
Bacteroides/inmunología , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/microbiología , Mucosa Intestinal/inmunología , Mucosa Intestinal/microbiología , Biopsia , Niño , Colon/inmunología , Colon/microbiología , Colon/patología , Enfermedad de Crohn/patología , Expresión Génica/efectos de los fármacos , Expresión Génica/inmunología , Humanos , Interleucina-1beta/inmunología , Interleucina-1beta/farmacología , Interleucina-8/genética , Interleucina-8/inmunología , Mucosa Intestinal/patología , Metagenoma/inmunología , Técnicas de Cultivo de Órganos , ProbióticosAsunto(s)
Displasia Fibrosa Poliostótica/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Mutación de Línea Germinal , Mosaicismo , Preescolar , ADN/química , ADN/genética , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Displasia Fibrosa Poliostótica/patología , Haplotipos , Humanos , Lactante , Masculino , Mutagénesis Insercional , Linaje , Polimorfismo Conformacional Retorcido-SimpleAsunto(s)
Líquido del Lavado Bronquioalveolar/química , Quimiocinas CXC , Quimiocinas/análisis , Péptidos y Proteínas de Señalización Intercelular , Surfactantes Pulmonares/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/metabolismo , Quimiocina CCL2/análisis , Quimiocina CXCL1 , Factores Quimiotácticos/análisis , Sustancias de Crecimiento/análisis , Humanos , Recién NacidoAsunto(s)
Adaptación Fisiológica , Mucosa Intestinal/patología , Intestino Delgado/patología , Activación de Linfocitos , Mitógenos de Phytolacca americana/toxicidad , Linfocitos T/inmunología , Atrofia , Tejido Conectivo/embriología , Tejido Conectivo/inmunología , Tejido Conectivo/patología , Dexametasona/farmacología , Edad Gestacional , Humanos , Hiperplasia , Inmunosupresores/farmacología , Mucosa Intestinal/embriología , Mucosa Intestinal/inmunología , Intestino Delgado/embriología , Intestino Delgado/inmunología , Activación de Linfocitos/efectos de los fármacos , Microscopía de Contraste de Fase , Técnicas de Cultivo de Órganos , Mitógenos de Phytolacca americana/farmacología , Linfocitos T/efectos de los fármacos , Tacrolimus/farmacologíaAsunto(s)
Enfermedades Inflamatorias del Intestino/inmunología , Factor de Necrosis Tumoral alfa/metabolismo , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/patología , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/patología , Humanos , Inmunidad Mucosa , Inmunohistoquímica , Enfermedades Inflamatorias del Intestino/patología , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Activación de Macrófagos , Distribución TisularRESUMEN
The aim of this systematic review was to evaluate the efficacy of amino acid-based formulas (AAF) in patients with cow's milk allergy (CMA). Studies were identified using electronic databases and bibliography searches. Subjects eligible for inclusion were patients of any age with CMA or symptoms suggestive of it. Comparisons of interest were AAF vs. extensively hydrolysed formula (eHF), AAF vs. soy-based formula (SF) and AAF vs. cow's milk or cow's milk-based formula. Outcomes of interest were gastrointestinal (GI), dermatological, respiratory and behavioural symptoms as well as growth. A total of 20 studies [three head-to-head randomized controlled trials (RCTs), three cross-over challenge RCTs, seven clinical trials (CTs) and seven case reports (CRs)] were included in the review. In infants with confirmed or suspected CMA, the use of an AAF was shown to be safe and efficacious. Findings from RCT comparisons of AAF with eHF showed that both formulas are equally efficacious at relieving the symptoms of CMA in confirmed or suspected cases. However, infants in specific subgroups (e.g. non-IgE mediated food-induced gastro-enterocolitis-proctitis syndromes with failure to thrive, severe atopic eczema, or with symptoms during exclusive breastfeeding) were more likely overall to benefit from AAF, as intolerance to eHF may occur. In such cases, symptoms persisting despite eHF feeding usually remit on AAF, and catch-up growth may be seen. Meta-analysis of the findings was not possible due to lack of homogenous reporting of outcomes in the original trials. This systematic review shows clinical benefit from use of AAF in both symptoms and growth in infants and children with CMA who fail to tolerate eHF. Further studies are required to determine the relative medical or economic value of initial treatment with AAF in infants at high risk of eHF intolerance.
Asunto(s)
Aminoácidos , Alimentos Infantiles , Fórmulas Infantiles , Hipersensibilidad a la Leche , Leche Humana , Leche , Leche de Soja , Aminoácidos/efectos adversos , Animales , Lactancia Materna/efectos adversos , Bovinos , Estudios Cruzados , Bases de Datos Factuales , Dermatitis Atópica/dietoterapia , Dermatitis Atópica/inmunología , Dermatitis Atópica/patología , Enteritis/dietoterapia , Enteritis/inmunología , Enteritis/patología , Insuficiencia de Crecimiento/dietoterapia , Insuficiencia de Crecimiento/inmunología , Insuficiencia de Crecimiento/patología , Humanos , Inmunoglobulina E/inmunología , Lactante , Alimentos Infantiles/efectos adversos , Recién Nacido , Metaanálisis como Asunto , Leche/efectos adversos , Hipersensibilidad a la Leche/dietoterapia , Hipersensibilidad a la Leche/inmunología , Hipersensibilidad a la Leche/patología , Proctitis/dietoterapia , Proctitis/inmunología , Proctitis/patología , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Antibiotics are increasingly prescribed in the peripartum period, for both maternal and fetal indications. Their effective use undoubtedly reduces the incidence of specific invasive infections in the newborn, such as group B streptococcal septicaemia. However, the total burden of infectious neonatal disease may not be reduced, particularly if broad-spectrum agents are used, as the pattern of infections has been shown to alter to allow dominance of previously uncommon organisms. This area has been relatively understudied, and there are almost no studies of long-term outcome. Recent findings suggest that such long-term data should be sought. First, there is evidence that organisms initially colonising the gut at birth may establish chronic persistence in many children, in contrast to prompt clearance if first encountered in later infancy, childhood or adulthood. Second, there is a rapidly advancing basic scientific data showing that individual members of the gut flora specifically induce gene activation within the host, modulating mucosal and systemic immune function and having an additional impact on metabolic programming. We thus review the published data on the impact of perinatal antibiotic regimens upon composition of the flora and later health outcomes in young children and summarise the recent scientific findings on the potential importance of gut flora composition on immune tolerance and metabolism.