Comparative evaluation of nonradiometric BACTEC and improved oxoid signal blood culture systems in a clinical laboratory.

The BACTEC NR660 blood culture system, which uses infrared spectroscopy to detect carbon dioxide generated by bacterial growth, was compared with the new medium formulation of the Oxoid Signal system. Two trials were conducted: a comparative study of 88 organisms in simulated blood cultures and a clinical trial of 3,321 paired patient blood culture samples. Both trials showed that overall the BACTEC system performed better in the recovery of organisms. The Oxoid system was unable to detect by signal the growth of the majority of yeasts, nonfermentative gram-negative bacilli, Neisseria meningitidis, Nocardia spp., and Corynebacterium jeikeium. There were no significant differences in the yield of Staphylococcus spp., members of the family Enterobacteriaceae, Streptococcus spp., or anaerobic organisms. BACTEC detected growth more quickly than did the Oxoid system; 61% of the isolates were detected by BACTEC at 24 h, while 49% of the isolates were detected by Oxoid. The Oxoid system had a high proportion (58.5%) of false-positives, compared with 7.7% for the BACTEC system. Despite the new medium formulation of the Oxoid system, its performance is still not equivalent to that of the BACTEC system.     

Co-infection of two beta-herpesviruses (CMV and HHV-7) as an increased risk factor for 'CMV disease' in patients undergoing renal transplantation

The ubiquity of human cytomegalovirus (CMV) and human herpesvirus-7 (HHV-7), as well as activation of these viruses during immunosuppression, allows the suggestion that both viruses could participate in the development of 'CMV disease' in patients after renal transplantation (RT). The aim of our research was to study the prevalence of latent CMV and HHV-7 infections in patients before RT, to determine interaction between these viruses in dual infection and possible association of their reactivation with the progression of 'CMV disease' after RT. Peripheral blood samples were collected from 49 patients before and up to 10-12 wk after RT. The methods used for diagnostics of viral infections were: serology, nested polymerase chain reaction (nPCR) analysis of peripheral blood leukocytes (PBL) and plasma, and virus isolation in cell cultures (morphological changes, nPCR analysis of cellular and cell-free samples, indirect immunofluorescence analysis). Before RT, CMV and HHV-7 DNAs were detected in PBL but not in the plasma samples, which indicates the presence of latent viral infection in patients. Latent dual (CMV + HHV-7) infection was prevalent (51.0%) in 49 patients, while CMV and HHV-7 infections alone were detected in 26.5 and 12.2% of patients, respectively. Risk of viral disease after RT, for recipients with latent dual infection before RT, was 12- and 2.2-fold higher in comparison with CMV and HHV-7 infections alone, respectively. Frequency of dual infection in 18 recipients with 'viral syndrome' or 'CMV disease' after RT was reliably higher (13/18, 81.3%) than CMV (1/18, 6.2%) (p < 0.025) and HHV-7 (2/18, 12.5%) (p < 0.025) infections alone. HHV-7 reactivation preceded CMV reactivation in 77.0% of the cases of dual infection in the recipients with viral disease and reactivation of both viruses preceded the development of viral disease. Severe 'CMV disease' developed in 2 out of 2 recipients with CMV primary infection and 'viral syndrome' in 1 recipient with CMV reinfection. The reactivation of CMV was detected in all recipients prior to onset of the disease. Correlation was shown between reactivation of latent HHV-7 infection and development of febrile syndrome in 2 out of 2 recipients with HHV-7 infection alone. Taking into account that dual infection is an increased risk factor for 'viral syndrome' and 'CMV disease' development, screening diagnostic should include testing for both viral infections in transplant donors as well as in recipients before and after RT.     

Effect of Different Types of Intermittent Fasting on Biochemical and Anthropometric Parameters among Patients with Metabolic-Associated Fatty Liver Disease (MAFLD)—A Systematic Review

Metabolic-associated fatty liver disease (MAFLD), previously called non-alcoholic fatty liver disease (NAFLD), is the most common chronic liver disease worldwide. It is characterised by excessive fat accumulation in hepatocytes. Currently, no pharmacological therapy is effective for this disease, so non-pharmacological alternatives such as diet, supplementation or physical activity are being sought. For this reason, we reviewed the available databases to analyse the studies conducted to date using different modifications of intermittent fasting among patients with MAFLD. Eight studies using this dietary strategy were included in this review. The results obtained in the different trials are varied and do not allow a clear determination of the effect of the different types of intermittent fasting on anthropometric and biochemical parameters among patients with MAFLD. However, this type of diet seems to show some therapeutic potential, but further studies are needed.     

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome – Evidence for an autoimmune disease

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a frequent and severe chronic disease drastically impairing life quality. The underlying pathomechanism is incompletely understood yet but there is convincing evidence that in at least a subset of patients ME/CFS has an autoimmune etiology. In this review, we will discuss current autoimmune aspects for ME/CFS. Immune dysregulation in ME/CFS has been frequently described including changes in cytokine profiles and immunoglobulin levels, T- and B-cell phenotype and a decrease of natural killer cell cytotoxicity. Moreover, autoantibodies against various antigens including neurotransmitter receptors have been recently identified in ME/CFS individuals by several groups. Consistently, clinical trials from Norway have shown that B-cell depletion with rituximab results in clinical benefits in about half of ME/CFS patients. Furthermore, recent studies have provided evidence for severe metabolic disturbances presumably mediated by serum autoantibodies in ME/CFS. Therefore, further efforts are required to delineate the role of autoantibodies in the onset and pathomechanisms of ME/CFS in order to better understand and properly treat this disease.     

Ethical issues in organ transplantation

Critical care clinicians are central to the organ transplantation process and therefore should be aware of the myriad ethical issues it raises. Organ donation can transform the lives of transplant recipients. However, it also warrants particular ethical scrutiny. Organ procurement is a procedure that cannot physically benefit the patient upon whom it is performed. Moreover, the potential donor incapacitated by terminal illness is usually unable to actively consent to donation. This article reviews contemporary debates in vital organ transplantation, including the definition of death, perimortem interventions and research, and merits of ‘opt-in’ versus ‘opt-out’ donor registries.     

Relationship between beta‐herpesviruses reactivation and development of complications after autologous peripheral blood stem cell transplantation

The relationship between beta‐herpesviruses reactivation and the development of complications after autologous peripheral blood stem cell transplantation was investigated. Viral genomic sequences were detected by the polymerase chain reaction, virus‐specific antibodies by ELISA, and human herpesvirus (HHV)‐6 variants by restriction endonuclease analysis. Virus reactivation, serum levels of tumor necrosis factor (TNF)‐α, interleukin (IL)‐1β, IL‐6, soluble IL‐2 receptor (sIL‐2R), IL‐2, and IL‐4 were compared with clinical features in 44 patients before and after transplantation. Anti‐CMV and anti‐HHV‐6 antibodies were found in 70.5% and 81.8% of patients, respectively. The frequency of plasma viremia was significantly higher in patients after transplantation (41% vs. 11.4%). Reactivation of more than one virus was identified in 55.6% of patients and reactivation of HHV‐7 alone in 44.4%. In cases of concurrent infection, HHV‐7 was reactivated before HHV‐6, and both HHV‐6 and HHV‐7 were reactivated before CMV. There was a significant increase in HHV‐6 load in peripheral blood leukocytes DNA during viremia. In all cases HHV‐6B variant was detected. Complications after transplantation occurred in 27.3% of patients and virus reactivation was detected in all patients with complications. The significant increases in the rate of HHV‐6 and HHV‐7 reactivation and in serum levels of TNF‐α, IL‐1β, and sIL‐2R, as well as aggravated immunosuppression, suggest that both viruses were involved in the complications after autologous peripheral blood stem cell transplantation, via their immunomodulatory activity. The kinetics of reactivation suggests a potential role of HHV‐7 as a co‐factor of HHV‐6 reactivation, and of both HHV‐6 and HHV‐7 as co‐factors of CMV reactivation. J. Med. Virol. 84:1953–1960, 2012. © 2012 Wiley Periodicals, Inc.     

Comparison of Diazinon Toxicity to Embryos of <Emphasis Type="Italic">Xenopus laevis</Emphasis> and <Emphasis Type="Italic">Danio rerio</Emphasis>; Degradation of Diazinon in Water

The aim of this study was to determine the toxic effect of diazinon (organophosphate insecticide) to embryos of Xenopus laevis and Danio rerio. The 96-h LC₅₀ values showed higher toxicity of diazinon for X. leavis in standard solution (9.84 mg/L) compared to the pond water (12.64 mg/L). Teratogenic index for diazinon was 1.3 and 1.6, respectively. The 96-h LC₅₀ diazinon values demonstrated similar sensitivity of embryos D. rerio (8.21–9.34 mg/L) and X. laevis in standard test solutions. Our results reflect that direct application of diazinon into the water can be associated with significant risks to aquatic organisms.