Paulo Fernando Souto Bittencourt

Clinical and Laboratory Predictors of Esophageal Varices in Children and Adolescents With Portal Hypertension Syndrome

Objectives: To determine the clinical and laboratory parameters that may predict the presence of esophageal varices in children and adolescents with portal hypertension. Patients and Methods: Overall, 111 patients with portal hypertension and no previous history of digestive bleeding underwent esophagogastroduodenoscopy for detection of esophageal varices. A univariate analysis initially was carried out, followed by a logistic regression analysis to identify the independent variables associated with the presence of esophageal varices. Sensitivity and specificity rates, positive predictive value, negative predictive value, and the accuracy of the predictive variables identified among cirrhotic patients were calculated with the esophagogastroduodenoscopy as the reference test. Results: Sixty percent of patients had esophageal varices on the first esophagogastroduodenoscopy. Patients with portal vein thrombosis and congenital hepatic fibrosis were 6.15-fold more likely to have esophageal varices than cirrhotic patients. When we analyzed 85 cirrhotic patients alone, splenomegaly and hypoalbuminemia remained significant indicators of esophageal varices. Only spleen enlargement showed appropriate sensitivity and negative predictive value (97.7% and 91.7%, respectively) to be used as a screening test for esophageal varices among cirrhotic patients. Conclusions: In reference services and research protocols, endoscopic screening should be performed in all patients with portal vein thrombosis and congenital hepatic fibrosis. Among cirrhotic patients, the indication should be conditioned to clinical evidence of splenomegaly or hypoalbuminemia. For clinicians, the recommendation is to emphasize the orientations given to guardians of patients with portal vein thrombosis and congenital hepatic fibrosis as to the risk of digestive bleeding. Cirrhotic patients with hypoalbuminemia and splenomegaly should receive the same orientations.

A regulatory instead of an IL-17 T response predominates in Helicobacter pylori-associated gastritis in children

Th17 cells seem to have an important role in the efficacy of vaccines against Helicobacter pylori. Because children are a target group for human vaccination and Th17/T(reg) cells have intrinsically linked and antagonic commitments, we compared the gastric levels of Th17- and T(reg)-associated cytokines of children and adults. IL-6, IL-10 and TGF-β1 levels and Foxp3(+) cell numbers were higher, but IL-1β, IL-17A and IL-23 were lower in infected children than in infected adults. In conclusion T(reg) instead of Th17 cell response to H. pylori-infection predominates in children.

Iron Status and Helicobacter pylori Infection in Symptomatic Children: An International Multi-Centered Study

Objective Iron deficiency (ID) and iron deficiency anaemia (IDA) are global major public health problems, particularly in developing countries. Whilst an association between H. pylori infection and ID/IDA has been proposed in the literature, currently there is no consensus. We studied the effects of H. pylori infection on ID/IDA in a cohort of children undergoing upper gastrointestinal endoscopy for upper abdominal pain in two developing and one developed country. Methods In total 311 children (mean age 10.7±3.2 years) from Latin America - Belo Horizonte/Brazil (n = 125), Santiago/Chile (n = 105) - and London/UK (n = 81), were studied. Gastric and duodenal biopsies were obtained for evaluation of histology and H. pylori status and blood samples for parameters of ID/IDA. Results The prevalence of H. pylori infection was 27.7% being significantly higher (p<0.001) in Latin America (35%) than in UK (7%). Multiple linear regression models revealed H. pylori infection as a significant predictor of low ferritin and haemoglobin concentrations in children from Latin-America. A negative correlation was observed between MCV (r = −0.26; p = 0.01) and MCH (r = −0.27; p = 0.01) values and the degree of antral chronic inflammation, and between MCH and the degree of corpus chronic (r = −0.29, p = 0.008) and active (r = −0.27, p = 0.002) inflammation. Conclusions This study demonstrates that H. pylori infection in children influences the serum ferritin and haemoglobin concentrations, markers of early depletion of iron stores and anaemia respectively.

Endoscopic repair of a large colonoscopic perforation with clips

We report a patient with a large colonic perforation that occurred in a screening colonoscopy, successfully repaired with endoclips, although the safety and efficacy of this approach is not entirely established. Endoscopic clip placement can be used to treat iatrogenic colonic perforation, when the defect is readily recognized and is easily accessible for closure, and the bowel preparation is excellent.

Gastroduodenal peptic ulcer and Helicobacter pylori infection in children and adolescents.

OBJECTIVES To show important aspects of gastroduodenal peptic ulcer and of Helicobacter pylori infection in children and adolescents. SOURCES Technical textbooks and MEDLINE and LILACS databases including publications between 1966 and 2006. SUMMARY OF THE FINDINGS The etiology of peptic ulcer in children and adolescents may be primary, associated with H. pylori infection, or secondary, in which etiopathogenic mechanisms rely upon the underlying disease. The infection is acquired predominantly in childhood, with prevalence rates between 56.8 and 83.1% in children who live in the poorest Brazilian regions, amounting to nearly 10% in children aged less than 10 years in industrialized countries. The infection can be diagnosed by invasive methods, which investigate the presence of the bacterium, or of DNA, RNA or bacterial products in biopsy fragments of the gastric mucosa obtained at endoscopic examination; it can also be diagnosed through noninvasive methods, which include the detection of anti-H. pylori antibodies in serum, urine or saliva samples, detection of bacterial antigens in stool samples, and the carbon 13-labeled urea breath test. However, upper gastrointestinal endoscopy is the method of choice for the diagnosis of peptic ulcer, as it allows collecting fragments from the gastric mucosa during the procedure for the diagnosis of infection and for histopathological analysis. CONCLUSION H. pylori infection is the major cause of peptic ulcer among children. Eradication of the bacterium with antimicrobial therapy results in the cure of the disease, and is therefore indicated for all children with H. pylori infection with an active, recurrent, healed, or complicated peptic ulcer.

Toll-like receptor (TLR2, TLR4 and TLR5) gene polymorphisms and Helicobacter pylori infection in children with and without duodenal ulcer

Helicobacter pylori infection is mainly acquired in childhood, and polymorphisms in the host genes coding for Toll-like receptors (TLRs) may influence the innate and adaptive immune response to the infection, affecting the susceptibility to H. pylori or the disease outcomes. Our aim was to investigate whether TLR4, TLR2, and TLR5 polymorphisms were associated with H. pylori susceptibility and risk for duodenal ulcer in children. Gastric biopsy specimens were obtained at endoscopy for evaluation of H. pylori status, TLR4, TLR2 and TLR5 polymorphisms from 486 children (254 H. pylori-negative and 232 H. pylori-positive: 72 with and 160 without duodenal ulcer). cagA status of H. pylori infection was investigated by PCR. The levels of gastric cytokines were detected by ELISA. H. pylori-positivity or duodenal ulcer were not associated with TLR2, TLR4 or TLR5 polymorphisms. Otherwise, the presence of TLR4 polymorphic allele was associated with infection by cagA-positive strains and with increased gastric levels of interleukin-8 and interleukin-10. TLR4 polymorphism might ultimately contribute to more severe consequences of the infection in adulthood since it was associated with susceptibility to cagA-positive H. pylori infection early in life.

Endoscopic dilatation of esophageal strictures in children and adolescents

OBJECTIVE To assess the causes of esophageal stricture in pediatric patients and their response to endoscopic dilatation. METHODS Retrospective analysis of clinical and endoscopic data obtained from children and adolescents with esophageal stricture submitted to endoscopic dilatation between July 1993 and January 2003. RESULTS A total of 125 patients aged between 1 month and 16 years were included in the study. Among the types of stenosis, postoperative (43.2%), corrosive (27.2%) and peptic (21.6%) strictures were the most prevalent. Those patients with corrosive esophageal stricture needed more dilatation sessions. Five cases of esophageal perforation and one case of hemorrhage occurred due to complications during the procedure. Good response to endoscopic treatment was described in 74.4% of cases, but better results were obtained from patients with peptic esophageal stricture. CONCLUSIONS Endoscopic treatment of esophageal strictures in children and adolescents yields good results and has a low rate of complications. Corrosive esophageal strictures have a higher morbidity and require more dilatation sessions.

IL2-330G polymorphic allele is associated with decreased risk of Helicobacter pylori infection in adulthood

We evaluated whether polymorphisms in genes coding molecules linked to the innate and adaptive immune response are associated with susceptibility to Helicobacter pylori infection. IL1B-511C-->T, IL1B-31T-->C, IL1RN allele 2, IL2-330T-->G, TNFA-307G-->A, TLR2Arg677Trp, TLR2Arg753Gln, TLR4Asp299Gly, and TLR5(392STOP) polymorphisms were determined in 541 blood donors. IL2-330T-->G allele carriers had a decreased H. pylori infection risk (OR=0.63, 95% CI=0.43-0.93) after adjustment for demographic and environmental factors. Hence, we investigated whether the polymorphism is functional by evaluating IL-2 serum concentration in 150 blood donors and 100 children. IL-2 pro-inflammatory and anti-inflammatory properties were indirectly investigated by determining serum IFN-gamma and IL-10/TGF-beta levels. The polymorphism was associated with increased mean IL-2 levels in H. pylori-positive adults (2.65 pg/mL vs. 7.78 pg/mL) and children (4.19 pg/mL vs. 8.03 pg/mL). Increased IL-2 was associated with pro-inflammatory activity in adults (IFN-gamma=18.61 pg/mL vs. 25.71 pg/mL), and with anti-inflammatory activity in children (IL-10=6.99 vs. 14.17 pg/mL, TGF-beta=45.88 vs. 93.44 pg/mL) (p<10(-3) for all). In conclusion, in the context of H. pylori infection, IL2-330 T-->G polymorphism is functional and is associated with decreased risk of infection in adults.

Úlcera péptica gastroduodenal e infecção pelo Helicobacter pylori na criança e adolescente

OBJECTIVE: To show important aspects of gastroduodenal peptic ulcer and of Helicobacter pylori infection in children and adolescents. SOURCES: Technical textbooks and MEDLINE and LILACS databases including publications between 1966 and 2006. SUMMARY OF THE FINDINGS : The etiology of peptic ulcer in children and adolescents may be primary, associated with H. pylori infection, or secondary, in which etiopathogenic mechanisms rely upon the underlying disease. The infection is acquired predominantly in childhood, with prevalence rates between 56.8 and 83.1% in children who live in the poorest Brazilian regions, amounting to nearly 10% in children aged less than 10 years in industrialized countries. The infection can be diagnosed by invasive methods, which investigate the presence of the bacterium, or of DNA, RNA or bacterial products in biopsy fragments of the gastric mucosa obtained at endoscopic examination; it can also be diagnosed through noninvasive methods, which include the detection of anti-H. pylori antibodies in serum, urine or saliva samples, detection of bacterial antigens in stool samples, and the carbon 13-labeled urea breath test. However, upper gastrointestinal endoscopy is the method of choice for the diagnosis of peptic ulcer, as it allows collecting fragments from the gastric mucosa during the procedure for the diagnosis of infection and for histopathological analysis. CONCLUSIONS: H. pylori infection is the major cause of peptic ulcer among children. Eradication of the bacterium with antimicrobial therapy results in the cure of the disease, and is therefore indicated for all children with H. pylori infection with an active, recurrent, healed, or complicated peptic ulcer.

Th1 immune response to H. pylori infection varies according to the age of the patients and influences the gastric inflammatory patterns

To compare children and adults in respect to the effect of H. pylori infection on the gastric concentrations of cytokines linked to innate and Th1 immune response, as well as to investigate the changes in the gastric concentrations of the studied cytokines according to the age. We studied 245 children (142 H. pylori-negative and 103 H. pylori-positive) and 140 adults (40 H. pylori-negative and 100 H. pylori-positive). The gastric concentrations of cytokines representative of the innate and Th1 response were higher in the H. pylori-positive than in the -negative children and adults. The gastric concentrations of IL-1α and TNF-α were significantly higher, while those of IL-2, IL-12p70 and IFN-γ were lower in the infected children than in the infected adults. In the infected children, the gastric concentration of IL-1α, IL-2, IL-12p70 and IFN-γ increased, whereas in adults, the gastric concentrations of IFN-γ and IL-12p70 decreased with the aging. Increased gastric concentration of Th1 associated cytokines correlated with increased degree of gastritis that is the background lesion for the development of the H. pylori associated severe diseases. Concluding, Th1 response to H. pylori infection varies according to the age and seems to have determinant implication in the H. pylori infection outcomes.