The Impact of Hepatitis C Virus Genotypes on Oxidative Stress Markers and Catalase Activity.

Hepatitis C virus (HCV) is a major cause of liver disease worldwide. Chronic HCV infections are usually associated with increased oxidative stress in the liver tissue. The intensity of oxidative stress may be a detrimental factor in liver injury and may determine the severity of the disease. The aim of the present case-control study was to determine the level of lipid peroxidation (TBARS), protein oxidative modification (AOPP), and catalase activity in sera of patients infected with HCV, in relation to different HCV genotypes and viral load. Considering the HCV patients with chronic hepatitis C (52) and control subject (50) recruitment, the study was designed as a case-control-type. The HCV RNA isolation, viral load, and HCV genotyping were performed according to the standard protocols. A significant difference compared to control healthy subjects was reported for TBAR (p < 0.001), AOPP (p = 0.001), and catalase activity (p = 0.007). In a gender-based comparison, a significantly higher level of AOPP for females was reported (p < 0.001). As stratified by HCV genotype, the most common was HCV-1 (HCV-1a and HCV 1b), with the overall participation of more than 60%, followed by genotype 3, while the least represented was genotype 2. No significant difference was documented among genotypes in regard to oxidative stress markers, although somewhat higher TBARS level, but not significant, was registered in patients infected with genotype 1b. A statistically significant positive correlation was found between the concentration of HCV genome copies and AOPP (r = 0.344; p = 0.012). A high level of HCV viral load was more likely to have a higher TBARS, but still without statistical significance (p = 0.072). In conclusion, the results obtained confirmed an imbalance between the ROS production and antioxidative defense system in HCV-infected patients. Since oxidative stress may have a profound influence on disease progression, fibrosis, and carcinogenesis, our results may meet the aspirations of mandatory introduction of antioxidants as early HCV therapy to counteract ROS consequences.

Community-acquired Clostridium difficile infection in Serbian pediatric population.

Carriage of Clostridium (C.) difficile in the intestinum of children, as well as its role in the disease (diarrhea) onset, is still controversial. The aim of this study is to investigate the community-acquired Clostridium difficile infection (CA-CDI) in Serbian pediatric population and to describe the basic clinical characteristics and risk factors for CA-CDI occurrence in Serbian pediatric population. The data obtained from 63 Serbian pediatric patients with CA-CDI and from control group of 126 children with community-acquired diarrhea, whose stool specimens were negative for C. difficile and toxins A/B, were mutually compared. In the current work, we found that children with CA-CDI display a significantly less severe disease clinical presentation than children with diarrheas of other origin. Lethal outcome was noted in two cases, but in children with severe underlying diseases (Crohn's disease and leukemia). By using the multivariate statistical regression model, the following statistically significant risk factors for community-acquired C. difficile-associated diarrhea development were determined: previous application of laxatives (OR = 0.199, CI 0.55-0.79, p = 0.015), general antibiotic use during the previous 2 months (OR = 0.05, CI 0.02-0.17, p < 0.001), and specifically the use of penicillins (OR = 0.112, CI 0.04-0.31, p < 0.0001) and cephalosporins (OR = 0.16, CI 40.06-0.44, p < 0.0001). Antibiotics from the groups of cephalosporins and penicillins were found to be the most important independent risk factors. Laxative application plays a significant role in the community-acquired Clostridium difficile infections in children, with mechanisms that are not completely understood.

SUSCEPTIBILITY OF RESPIRATORY ISOLATES OF STREPTOCOCCUS PNEUMONIAE ISOLATED FROM CHILDREN HOSPITALIZED IN THE CLINICAL CENTER NIS.

INTRODUCTION: Streptococcus pneumoniae is one of the most common causes of respiratory infections. The aim was to study the susceptibility to antimicrobial agents of respiratory isolates ofStreptococcus pneumoniae obtained from hospitalized children. MATERIAL AND METHODS: A total of 190 respiratory pneumococcal isolates obtained from children aged from 0 to 14 years were isolated and identified by using standard microbiological methods. Susceptibility to oxacillin, erythromycin, clindamycin, tetracycline, cotrimoxazole, ofloxacin and rifampicin was tested by disc diffusion method. Minimal inhibitory concentrations for amoxicillin and ceftriaxone were determined by means of E test. The macrolide-resistant phenotype was detected by double disc diffusion test. RESULTS: All tested isolates were susceptible to amoxicillin and ceftriaxone. The minimal amoxicillin concentration inhibiting the growth of 50% of isolates and of 90% of isolates was 0.50 microg/ml and 1.0 microg/ml, respectively and the minimal ceftriaxone concentration inhibiting the growth of 50% of isolates and of 90% of isolates was 0.25 microg/ml and 0.50 microg/ml, respectively. Susceptibility to erythromycin and clindamycin was observed in 21.6% and 29.47% of isolates, respectively. The resistence to macrolides-M phenotype was detected in 10.07% of isolates and constitutive macrolide-lincosamide-streptogramin phenotype (constitutive MLS phenotype) was found in 89.93% of isolates. All tested isolates were susceptible to ofloxacin and rifampicin. CONCLUSION: Amoxicillin could be the therapy of choice in pediatric practice. The macrolides should not be recommended for the empirical therapy of pneumococcal respiratory tract infection in our local area.

Serum anti-Helicobacter pylori IgA and IgG antibodies in asymptomatic children in Serbia.

The aim of this study was to determine the seroprevalence of Helicobacter pylori and the distribution of anti-H.pylori IgA and IgG antibodies in asymptomatic children aged between 7 and 18 y. We studied the serum samples of 283 children using the commercial ELISA test for the detection of anti-H. pylori IgA and IgG antibodies. The overall prevalence of anti-H. pylori antibodies was 36.4%. The seroprevalence was 35%, 28.3%, 37.5%, and 42.2% for the ages of 7, 10, 14 and 18 y, respectively. Serum IgG antibodies alone were detected in 88.3%, IgA alone in 4.9%, and both IgA and IgG antibodies were detected in 6.8% of samples. The mean levels of IgG antibodies to H. pylori increased with age. We concluded that the prevalence of H. pylori antibodies in Serbian children was high (36.4%), ranging from 35% to 42.2%. The detection of IgG antibodies is useful for the determination of seroprevalence in asymptomatic children.