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Since its first identification in Scotland, over 1000 cases of unexplained pediatric hepatitis in children have been reported worldwide, including 278 cases in the UK 1 . Here we report investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator subjects, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in liver, blood, plasma or stool from 27/28 cases. We found low levels of Adenovirus (HAdV) and Human Herpesvirus 6B (HHV-6B), in 23/31 and 16/23 respectively of the cases tested. In contrast, AAV2 was infrequently detected at low titre in blood or liver from control children with HAdV, even when profoundly immunosuppressed.AAV2, HAdV and HHV-6 phylogeny excluded emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T-cells and B-lineage cells.Proteomic comparison of liver tissue from cases and healthy controls, identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins.HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and in severe cases HHV-6B, may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children.

Because of the widespread occurrence of resistance to sulfonamides among Enterobacteriaceae, some researchers have suggested using trimethoprim (TMP) alone instead of the combination sulfamethoxazole-trimethoprin (SMX-TMP) in treating infections with TMP-susceptible organisms. To answer whether SMX-TMP suppresses the emergence of resistant organisms compared with TMP alone, quantitative fecal cultures were made for total and TMP-resistant organisms before, during, and after SMX-TMP (800/160 mg twice a day) or TMP (200 or 100 mg twice a day) was given to 48 patients for 4 weeks in a prospective, randomized study. All three regimens left anaerobes intact and reduced the total aerobic coliform fecal flora by approximately 4 logs throughout the 4-week treatment period. In 11 of 19 (58%) patients taking TMP 200 mg twice daily, TMP-resistant organisms emerged or increased during therapy (P < 0.01, compared with none of the 12 controls), whereas in only 4 of 18 (22%) patients on SMX-TMP did TMP-resistant organisms increase. These TMP-resistant organisms increased by less than 1 log and were predominantly Pseudomonas and Acinetobacter species. In only one instance did an SMX-TMP-resistant Escherichia coli strain emerge after 4 weeks of SMX-TMP therapy. The slight increase in Pseudomonas and Acinetobacter species seen with TMP alone in this study raises a potential risk of giving TMP alone in settings where these organisms may cause senous infections, as in immunosuppressed patients.The drug combination sulfamethoxazole and trimethoprim (SMX-TMP) has come into increasing use in many situations. Because Enterobacteriaceae are often resistant to SMX but susceptible to TMP (3), some have suggested that TMP alone may be just as effective in treating many infections, such as acute, uncomplicated urinary tract infections (1, 9). However, concern has arisen that TMP alone may lead to increased resistance over that seen with the combination SMX-TMP. Gram-negative bacteria were shown by Reisberg et al. to develop resistance rapidly when exposed to increasing TMP concentrations in vitro (17). In 1968, Darrell and his co-workers also demonstrated that exposure to TMP in vitro produced increased resistance among Escherichia coli, Proteus, and Klebsiella. They also showed that TMP resistance emerged faster among sulfonamide-resistant strains exposed to SMX-TMP than among sulfonamide-susceptible organisms (4). Bushby, in 1971, reported in vitro data showing that the presence of SMX added to TMP reduced the emergence of TMP resistance among E. coli that were moderately susceptible to SMX (2), although he questioned whether the TMP-resistant strains that emerged with the TMP alone had reduced virulence on the basis of growth characteristics and alteration of 0 antigenicity. However, although 20 to 40% of Enterobacteriaceae are resistant to SMX and despite the widespread use of the combination SMX-TMP, little TMP resistance has emerged to date. Furthermore, recent studies have failed to reveal the emergence of increased resistance with l...

BackgroundUrinary tract infections (UTIs) are one of the most common infections found in humans, with uropathogenic Escherichia coli (UPEC) being the most common cause. Prevention of UTI is a major global concern due to its recurrent nature, medical cost, and most importantly, the increased antimicrobial resistance among UPEC. The resistance in UPEC is mainly due to the Extended-Spectrum β-lactamases (ESBL), particularly the E. coli CTXM-15 type which is known for its rapid dissemination worldwide. Treatment options for E. coli CTXM-15 have become limited over recent years because of their multi-drug resistance, hence anti-virulent strategies based on herbal remedies, have considered as a viable option. The cranberry product, Cysticlean® capsules, contain 240 mg of proanthocyanins (PACs), which have been shown to significantly inhibit E. coli adherence, both in vitro and ex vivo, to uroepithelial cells.MethodIn this study, the cephalosporin-resistant E. coli isolate NCTC 1553 (E. coli CTXM-15) was analysed by qRT-PCR (quantitative Reverse Transcriptase -Polymerase Chain Reaction) for the expression of virulence factors after treatment with Cysticlean®. qRT-PCR was carried out to detect virulence determinants encoding for toxins SAT, and USP, the iron acquisition system ChuA, the protectins SoxS, KPSM, TraT and RecA, the antibiotic resistance gene CTX-M (encode β-lactamases), and the transporters IdfB and HcaT.ResultsCysticlean® significantly reduced the expression of all ten selected genes encoding for virulence factors and β-lactamases.ConclusionCranberry product Cysticlean® could represent a practicable alternative option for the prevention of recurrent UTI caused by multi-drug resistant E. coli CTXM-15, as the product acts on multiple bacterial targets.

Extended-Spectrum β-Lactamase (ESBL) producing bacteria are becoming increasingly prevalent in biofilmassociated infections. Bacteria form biofilms that allow their survival in hostile environments. The amount of formed biofilm is affected by external environmental factors. This study investigates the effect of specific parameters (media type, incubation condition, and growth stage) on the amount of produced biofilm on antibiotic resistant bacterial strains, Escherichia coli (CTX-M-15, TEM-3, and IMP-type) and Klebsiella pneumoniae (OXA-48, SHV-18, NDM-1, and KPC-3). The amount of biofilm formed was measured at different time points (6, 12, 24 and 48 h) of incubations under static and shaking conditions, using three different types of media (nutrient broth, LB broth, and AB broth). Statistical tests showed that there was a significant difference in biofilm level (p<0.01) for 64 out of 80 tests (80%) when grown under different types of media. Growing under different incubation conditions also showed a statistical difference in biofilm level (p<0.05) for 76 out of 120 tests (63%). Stage of growth of the same species also showed statistical difference, 20 out of 24 tests (83%) for E. coli and 24 out of 24 tests (100%) for K. pneumoniae. These findings suggested that biofilm formation is highly affected by incubation conditions, strains' stage of growth, and media type demonstrating that these conditions may play a role in adaptability of the ESBLs on different environmental conditions and their increased prevalence in biofilm associated infections.