Prevalence of celiac disease in a large cohort of young patients with type 1 diabetes

BACKGROUND

Serological screening for celiac disease (CD) allows the identification of individuals genetically predisposed, as type 1 diabetes mellitus (T1DM). However, the diagnosis is confirmed by intestinal biopsy. The aim was to determine the prevalence of immunoglobulin-A anti-tissue transglutaminase antibodies (IgA-tTG) and CD in a large cohort of young T1DM patients.

METHODS

Screening for CD was randomly conducted in 881 T1DM by IgA-tTG and total IgA. Individuals with positive antibodies were referred to endoscopy/duodenal biopsy.

RESULTS

The age of the cohort at the screening was 14.3 ± 5.9 years and at T1DM onset was 7.9 ± 4.4 years. The prevalence of positive serology was 7.7%. Median IgA-tTG levels were 117.7 U/mL (interquartile range [IQR] 35.7-131.5 U/mL). Of the 62 duodenal biopsy, CD was diagnosed in 79.0%, yielding an overall prevalence of 5.6%. The mean age of CD patients was 15.6 ± 6.5 years and, at T1DM onset was 6.3 years (4.0-9.9 years). The modified Marsh-Oberhuber histological classification was 22.5% (3a), 36.7% (3b), and 40.8% (3c). In the biopsy-proven patients, T1DM onset occurred at slightly younger ages (6.3 vs 9.7 years, P = 0.1947), gastrointestinal (GI) manifestations, predominantly abdominal pain and distension, were more prevalent (71.4% vs 38.5%, P = 0.027) and higher IgA-tTG titers (128.0 vs 26.3 U/mL, P = 0.0003) were found than in those with negative-biopsies.

CONCLUSION

Our results demonstrate the prevalence of 7.7% of IgA-tTG and 5.6% of CD in T1DM patients in South Brazil and, emphasize the importance of the screening in high-risk individuals. Furthermore, the presence of GI manifestations and higher IgA-tTG titers strongly suggest the diagnosis of CD.

Brain-Derived Neurotrophic Factor in Children and Adolescents with Cirrhosis Due to Biliary Atresia

BACKGROUND

The nutritional status in patients with cirrhosis is not so easy to assess properly. Considering the relationship between brain-derived neurotrophic factor (BDNF) and energy homeostasis, the main aim of this study was to evaluate the concentration of BDNF in children and adolescents with cirrhosis due to biliary atresia (BA) and correlate it with their nutritional status.

METHODS

Fifty-three children and adolescents with cirrhosis due to BA and 33 healthy controls were enrolled in this study. Nutritional status was evaluated using anthropometric parameters, and serum BDNF was measured by ELISA. Spearman coefficient was used to evaluate the correlation between variables.

RESULTS

In the cirrhosis group, 28.8% were undernourished and in the control group, 100% were well-nourished. BDNF median values for the control and cirrhosis group were 28.5 and 9.0 pg/ml respectively. BDNF and platelets were positively associated with both Standard Deviation Score (SDS) for height-for-age ratio and SDS for triceps skinfold thickness-for-age ratio.

CONCLUSIONS

Considering these associations, BDNF may be an indirect biomarker of nutritional status in children and adolescents with chronic liver disease. Further studies must be conducted to clarify the role of BDNF in this population.

Blood collection for biochemical analysis in adult zebrafish

The zebrafish has been used as an animal model for studies of several human diseases. It can serve as a powerful preclinical platform for studies of molecular events and therapeutic strategies as well as for evaluating the physiological mechanisms of some pathologies. There are relatively few publications related to adult zebrafish physiology of organs and systems, which may lead researchers to infer that the basic techniques needed to allow the exploration of zebrafish systems are lacking. Hematologic biochemical values of zebrafish were first reported in 2003 by Murtha and colleagues who employed a blood collection technique first described by Jagadeeswaran and colleagues in 1999. Briefly, blood was collected via a micropipette tip through a lateral incision, approximately 0.3 cm in length, in the region of the dorsal aorta. Because of the minute dimensions involved, this is a high-precision technique requiring a highly skilled practitioner. The same technique was used by the same group in another publication in that same year. In 2010, Eames and colleagues assessed whole blood glucose levels in zebrafish. They gained access to the blood by performing decapitations with scissors and then inserting a heparinized microcapillary collection tube into the pectoral articulation. They mention difficulties with hemolysis that were solved with an appropriate storage temperature based on the work Kilpatrick et al. When attempting to use Jagadeeswaran's technique in our laboratory, we found that it was difficult to make the incision in precisely the right place as not to allow a significant amount of blood to be lost before collection could be started. Recently, Gupta et al. described how to dissect adult zebrafish organs, Kinkle et al. described how to perform intraperitoneal injections, and Pugach et al. described how to perform retro-orbital injections. However, more work is needed to more fully explore basic techniques for research in zebrafish. The small size of zebrafish presents challenges for researchers using it as an experimental model. Furthermore, given this smallness of scale, it is important that simple techniques are developed to enable researchers to explore the advantages of the zebrafish model.

Shifting susceptibility to hepatitis A among children and adolescents over the past decade

OBJECTIVES

To estimate the prevalence of anti-hepatitis A virus (anti-HAV) antibodies in serum samples from children and adolescents obtained at two clinical pathology laboratories in the city of Porto Alegre, south of Brazil, and to compare findings to those of a study carried out in the 1990s.

METHODS

In this cross-sectional study conducted between 2007 and 2008, 465 serum samples obtained from subjects aged 1-19 years were consecutively tested to determine the prevalence of total anti-HAV antibodies. Samples were provided by a public laboratory (group 1) that serves the Unified Health System exclusively, meant to represent the lowest socioeconomic strata, and by a private laboratory (group 2), meant to represent the higher socioeconomic classes. Tests were performed at a single laboratory using commercially available electrochemiluminescence kits. Antibody levels ≥ 20 UI/L were considered positive.

RESULTS

The seroprevalence of anti-HAV in Group 1 was 37.6%. The percentage of anti-HAV reactivity increased from 19.4% in the 1-to-4 group to 54.1% in the 15-to-19 group. In Group 2, overall anti-HAV positivity was 46.1% and was inversely correlated with age, declining from roughly 50% in the youngest groups to 29.1% in the 15-to-19 group. Comparison of sample findings to those reported in a 1990s study showed a significant reduction in anti-HAV prevalence among 5-to-9-year-olds in group 1 (p = 0.03).

CONCLUSIONS

The results suggest that the endemicity of hepatitis A in Porto Alegre has been declining over the past decade, and that children and adolescents, particularly those in the lowest socioeconomic strata, are more susceptible to the disease.

Low plasma zinc concentrations in pediatric patients with cirrhosis

OBJECTIVE

To determine plasma zinc concentrations in children and adolescents with cirrhosis and to investigate the association between these results and dietary zinc intake, anthropometric data, and severity of liver disease.

METHODS

Plasma zinc concentration was assessed by atomic absorption spectrophotometry in 30 children and adolescents with cirrhosis (105.0+/-60.0 months; 22 girls) and 27 without liver disease (122.3+/-47.3 months, 14 girls). Dietary zinc data were evaluated by 3-day food intake records. Anthropometry measures included height, weight, skinfold thickness, brachial circumference, and upper arm muscle size. Severity of liver disease was classified according to the Child-Pugh, MELD, and PELD criteria.

RESULTS

The mean (+/- standard deviation) plasma zinc concentrations in control subjects and patients were 105.69+/-19.46 and 75.44+/-24.45 microg/dL, respectively (p < 0.001). No associations were found between anthropometric measures, dietary zinc intake, and plasma zinc concentration. There was statistical difference related to plasma zinc concentrations between Child-Pugh B + C patients and control subjects (p < 0.001), and concerning PELD, between patients below the cutoff score of 15 and those above (p = 0.002).

CONCLUSIONS

The prevalence of hypozincemia was 43% for patients with cirrhosis. Although low plasma zinc concentration was associated with more severe liver disease, it was present even in some Child-Pugh A patients. Therefore, zinc supplementation should be considered for cirrhotic children.

Biliary atresia: we still operate too late

OBJECTIVE

To analyze the age at surgery for children with biliary atresia and their survival periods without need for liver transplantation. The study was performed at Hospital de Clínicas de Porto Alegre, in Porto Alegre, state of Rio Grande do Sul, Brazil.

METHODS

The medical records of patients operated between 1982 and 2007 who were residents of the state of Rio Grande do Sul were reviewed.

RESULTS

Of the 112 cases of children with biliary atresia studied, 38 (33.9%) occurred between 1982 and 1989, 46 (41.1%) between 1990 and 1999 and 28 (25.0%) after 2000. Portoenterostomy was not performed for 12 cases (10.7%). Age at surgery ranged from 25 to 297 days (median: 80.5; IQR25-75: 61.3-109.0 days); for 20.5% of cases, the age was below 60 days. There was no age difference at diagnosis for the three decades in the study. Patients from the countryside (median: 87.0; IQR25-75: 69.0-115.0 days) were referred significantly later (p = 0.007) than those living in Porto Alegre and the metropolitan area (median: 68.0; IQR25-75: 55.5-98.0 days). The ratio of patients younger than 60 days was significantly lower (p = 0.013) for those from the countryside. Survival periods with native liver for all patients was 46.2% in 2 years, falling continuously until reaching 15.3% in 20 years. Patients operated before reaching 60 days of age had longer survival periods with native livers (log rank < 0.0001).

CONCLUSIONS

Late performance of portoenterostomy was a constant in the past 25 years, and this delay led to shorter survival periods with native livers for biliary atresia patients.

Amplification of bacterial DNA does not distinguish patients with ascitic fluid infection from those colonized by bacteria

OBJECTIVE

To evaluate 16S ribosomal RNA (rRNA) gene amplification to diagnose spontaneous bacterial peritonitis (SBP).

PATIENTS AND METHODS

According to a retrospective protocol, 31 patients with portal hypertensive ascites (serum to ascites albumin gradient > or = 1.1 g/dL) were studied. Ascitic fluid was analyzed as follows: Gram stain, aerobic and anaerobic cultures, polymorphonuclear cell count, and biochemical tests. Bacterial DNA was detected by polymerase chain reaction.

RESULTS

There were 8 episodes of SBP and 4 episodes of bacterascites (BA). Culture was positive in 4 of 8 cases of SBP and bacterial DNA was positive in 7 of 8 cases of SBP. Bacterial DNA was positive in 3 of 4 cases of BA and in 8 of 28 cases of culture-negative non-neutrocytic ascites (CNNNA). The PELD score, serum to albumin ascites gradient, and mortality showed no statistical difference between patients with CNNNA and the result of the bacterial DNA analysis.

CONCLUSIONS

Although the 16S rRNA gene amplification was better than culture to diagnose SBP, bacterial DNA does not seem to allow a distinction between ascites infection and ascites colonization.

Infected and noninfected ascites in pediatric patients

OBJECTIVES

To determine the prevalence of spontaneous bacterial peritonitis, ascites with bacterial infection and noninfected ascites in pediatric patients with portal hypertensive ascites and to compare the clinical and laboratory features of infected and noninfected ascites.

METHODS

Forty-one episodes of portal hypertensive ascites (serum-ascites albumin gradient >1.1 g/dL) in 31 patients were studied. Median age was 2.9 years. Twenty-four (77.4%) patients were cirrhotic and 20 (83.3%) were classified as Child-Pugh C. Median pediatric end-stage liver disease score was 18.5. The following ascites features were assessed: polymorphonuclear neutrophil cell count, cytology, pH, concentration of glucose, lactic dehydrogenase, total protein and albumin, Gram stain and bacteriological culture. Blood was sampled for complete blood count, coagulation studies, liver and renal function tests. Groups were compared by Mann-Whitney and chi tests (P < 0.05).

RESULTS

Noninfected ascites were observed in 29 of 41 samples, spontaneous bacterial peritonitis in eight of 41 and ascites with bacterial infection in four of 41. The most prevalent clinical features were fever, voluminous ascites and encephalopathy, but there were no significant differences in the clinical features of the groups. All patients with infected ascites were cirrhotic. There was no statistical difference in Child-Pugh or pediatric end-stage liver disease status between patients with infected and noninfected ascites. Culture of ascetic fluid was positive in four of eight cases of spontaneous bacterial peritonitis. Gram-negative rods were the most prevalent bacteria cultured. Except for serum albumin, no statistical differences in biochemical markers were observed between patients with infected and noninfected ascites.

CONCLUSIONS

The prevalence of infected ascites was 29.2%. With the exception of serum albumin, there were no differences in the clinical and biochemical features of patients with infected ascites and noninfected ascites.

[Digital morphometric and stereologic analysis of small intestinal mucosa in well-nourished and malnourished children with persistent diarrhea]

OBJECTIVE

To test the hypothesis that the proximal small intestines of children with persistent diarrhea present morphometric and stereologic changes proportional to their nutritional status, using microscope images stored in a computer.

METHODS

Cross-sectional study with 65 pediatric patients, whose ages ranged from 4 months to 5 years, with persistent diarrhea for over 14 days. The nutritional assessment was performed according to the z-scores for weight/age (W/A), weight/height (W/H) and height/age (H/A) ratios, divided into: well-nourished = z > or =2SD and malnourished = z<2SD; well-nourished = z > or =2SD, nutritional risk = z<1SD and malnourished = z<-2SD; and continuously, in descending order, using the NCHS charts. After obtaining the computer images using the software Scion Image, villous height, crypt depth, mucosal thickness, total mucosal thickness, and villous/crypt ratio were measured in the fragments of the small intestinal mucosa, enlarged 100 times. When images were enlarged 500 times, enterocyte height, nuclear height and brush-border height were measured. Stereologic analysis was performed using cycloid arcs.

RESULTS

For W/A, W/H and H/A z-scores, divided into two nutritional status categories, no statistically significant difference was observed in regard to villous height, crypt depth, mucosal thickness, total mucosal thickness and villous/crypt ratio. Enterocyte height presented the most significant difference between well-nourished and malnourished groups, for W/A and W/H ratios, with a 500x enlargement, although this difference was not statistically significant. When z-scores were subdivided into three nutritional status categories, a digital morphometric analysis showed a statistically significant difference for villous/crypt ratio between the well-nourished and slightly malnourished group and the well-nourished and mild to severe malnourished group (p=0.048). The villous/crypt ratio was higher among well-nourished children. Using the Spearman coefficient, the variables enterocyte height, height of enterocyte nucleus and brush-border height presented a clear association with the W/A ratio (r=0.25; p=0.038), W/H ratio (r=0.029; p=0.019). The height of the enterocyte and the brush-border height were associated with W/H ratio.

CONCLUSION

The observed associations between nutritional status and the analyzed small intestinal mucosa variables showed a positive correlation with patients' weight. Although these associations were of a slight to moderate magnitude, we observed a tendency of enterocyte size reduction, as well as a reduction in the size of its nucleus and brush-border, as the level of malnutrition increases.

[Blood levels of vitamin D in children and adolescents with chronic cholestasis]

OBJECTIVE

To verify blood levels of vitamin D in patients with chronic cholestasis, and relate them to nutritional status, length of time since the onset of cholestasis and use of vitamin supplement.

METHODS

Controlled cross-sectional study with chronic cholestasis as study factor and blood levels of vitamin D as outcome. The study included patients aged between 4 months and 18 years, who were cared for at the Pediatric Gastroenterology Unit of Hospital de Clínicas de Porto Alegre. Controls were eutrophic children in the same age range. Blood was collected for radioimmunoassay. Anthropometric analyses were performed, as was determination of the length of time since the onset of cholestasis and use of vitamin supplement.

RESULTS

22 patients and 17 controls were evaluated. Average vitamin D level in patients was 13.7 -/+ 8.39 ng/ml, compared to 25.58 -/+ 16.73 ng/ml in controls (p = 0.007). Prevalence of hypovitaminosis D in patients was 36%. Median of period of time since the onset of cholestasis was 1 year with variation of 6 months to the 25th percentile and 3.9 years to the 75th percentile. Anthropometric evaluation (NCHS) showed 36% of malnutrition by weight and 41% by height. Anthropometric evaluation according to Z score showed 33.3% and 23.8% prevalence of malnutrition for the criteria height/age and weight/age, respectively. The evaluation of weight regarding height did not show values below two standard deviations. No relationship was found between nutritional state, use of oral vitamin supplement and blood levels of vitamin D.

CONCLUSIONS

Blood levels of vitamin D in patients with cholestasis were lower than those of controls, but were not related to nutritional status, period of time since the onset of cholestasis or use of vitamin supplement.

[Prevalence of hepatitis A antibody in children and adolescents with chronic liver disease]

OBJECTIVE

To evaluate the prevalence of Hepatitis A virus (HAV) in children and adolescents with chronic liver disease in a unit of pediatric hepatology.

METHODS

Between May 1999 and February 2001, we studied the prevalence of anti-HAV in 60 children and adolescents with chronic liver disease, aged between 1 and 16 years, from the Unit of Pediatric Hepatology of the Hospital de Clínicas de Porto Alegre. The total anti-HAV was determined by a commercially available competitive ELISA method (Abbott), and compared with age, sex, race, etiologic diagnosis and family income of each patient.

RESULTS

A one-year old child was not included in the study because she presented twice with undetermined anti-HAV results. Among the other 59 patients, 14 (24%) presented a positive result of total anti-HAV. The ages of test-positive subjects varied between 1 and 16 years old (mean=7.7 years, median=8.5). The differences between positive and negative groups in relation to age, sex and race were not statistically significant. Family income was lower in anti-HAV positive patients, but this difference was not significant. The differences between the etiologies of liver diseases were probably more related to the age than to the etiologies of the diseases.

CONCLUSIONS

In the studied population, the majority (76%) of children and adolescents with chronic liver disease are susceptible to hepatitis A virus infection and, consequently, they could present a more severe disease or even fulminant hepatitis A. We strongly suggest that these subjects receive Hepatitis A inactivated vaccine.