In vitro antimicrobial synergy studies of carbapenem-resistant Acinetobacter baumannii isolated from intensive care units of a tertiary care hospital in Egypt

The increasing prevalence of multidrug-resistant and pan drug-resistant Acinetobacter baumannii as a cause of nosocomial infections has led to the need for the reassessment of novel combinations of antibiotics as our only current viable option for handling such infections until a new therapeutic option becomes available. Two of the most commonly used methods for testing antimicrobial synergy are the Time-kill assay method and the E-test method, and these were the methods used in this study. Antibiotic combinations tested in this study were azithromycin and polymyxin, tobramycin and polymyxin, polymyxin and rifampicin, and tobramycin and rifampicin. The azithromycin and polymyxin combination showed synergy, while the rifampicin and polymyxin combination showed antagonism. The synergy was achieved at lower MIC values than using each of the single agents alone against the same isolates. Synergy testing results varied according to the method used, and it is difficult to establish which method is more accurate. The use of these lower MIC values as a guide to determine effective therapeutic doses used in combination therapy can help to decrease the emergence of resistance and can also minimize the side effects associated with using a single agent at a higher dose. Further research is still required to predict in vivo efficacy of such combinations

Study of some T regulatory cell subsets in patients with multi-drug resistant pulmonary tuberculosis

Background: Regulatory T-cells are CD4[+] cells involved in the regulation of suppression of immune response during infection. Many studies revealed that the number of these cells, increase in patients with active pulmonary TB [PTB. Few studies addressed this problem in MDR-PTB

Objective: This work aimed at studying some T reg - cell subsets in patients with MDR-PTB, compared to those with active pulmonary TB who responded to treatment as well as to healthy control subjects

Methods: Three groups were included in the study [20, in each group], group of healthy control and 2 groups as patients' groups [patients with MDR-PTB and patients' with PTB responding to treatment]. Routine blood work and CXR were done for all subjects in addition to microbiological evaluation of sputum in patients' groups. T reg - cell subsets in peripheral blood were studied by flow cytometry, using monoclonal antibodies against the following markers, CD4, CD25 and FoxP3 for identification

Results: Patients' groups, had higher frequency of T reg cell subsets, CD4[+] CD25[+] FoxP3[+] than the group of healthy subject, [P < 0.01] and treatment responders' group had non-significantly higher percentage of these cells than in patients with MDR-PTB [P > 0.05], but highly significant statistical difference for the percentage of total CD4[+] [P < 0.01]. Patients' with more radiologically extensive disease, had higher level of these cells than, in other patients [P < 0.05], with significant positive correlation

Conclusion: Although immune suppression characteristic of T reg - cells seems important in the pathogenesis of MDR-PTB, other mechanisms, immunologic, on non-immunologic are important as well

T helper type 1/T helper type 17-related cytokines in chronic hepatitis C patients before and after interferon and ribavirin therapy

This study examined the T helper [Th] 1/Th17-related cytokines, interferon [IFN]- gamma and interleukin [IL]-17 in the serum of biopsy-proven chronic hepatitis C patients before and after IFN and ribavirin therapy to address whether or not viral clearance is related to Th1/Th17 cytokines. The serum levels of IFN-gamma and IL-17 were assayed by ELISA on 26 patients with chronic hepatitis C virus [HCV] infection before the start and 3 months after treatment with pegylated IFN-alpha plus ribavarin and compared with sera from 15 normal control subjects. IFN- gamma and IL-17 levels are higher in the serum of patients with chronic hepatitis than in normal controls and these elevated levels were not directly correlated [r = -0.01, p = 0.96 for IFN-gamma and r= - 0.08, p= 0.66 for IL-17] to the viremic state of the HCV infection. In contrast to IL-17, IFN-gammas showed significant reduction after 12 weeks of treatment with pegylated IFN plus ribavirin. However, IFN-gamma and IL-17 serum levels were not significantly [p= 0.19 and =0.70, respectively] different among responders are nonresponders for pegylated IFN plus ribavirin therapy. Our finding suggest that the combined treatment with pegylated IFN-alpha and ribavirin downmodulates the secretion of key cytokine IFN-gammas as early as 12 weeks after treatment in infected patients. These findings could encourage new exciting possibilities for immune-based interventions with the aim of restoring functional antiviral T cell responses combined with improved viral clearance

Direct molecular identification of Malassezia species from skin scales of patients with seborrheic dermatitis by nested terminal fragment length polymorphism analysis

Background: Malassezia yeasts are associated with several dermatological disorders. The conventional identification of Malassezia species by phenotypic conventional methods is complicated and time-consuming, and the results based on culture methods are difficult to interpret. This study aimed to perform a DNA-based procedure [nested terminal fragment length polymorphism analysis [tFLP]] directly applicable to pathological skin scales for the identification of seven Malassezia species. This technique involves nested PCR of the intergenic transcribed spacer [ITS] ITS I and ITS II region ribosomal gene clusters. All known Malassezia species can be differentiated by unique ITS fragment lengths

Subjects and methods: Specimens were taken from 14 patients with seborrheic dermatitis. Cultures were made in modified Dixon agar medium and the isolates were identified by the coventional methods: macroscopy, microscopy, catalase and Tween lipid assimilation tests. Skin scales were also directly analysed by nested terminal fragment length polymorphism analysis

Results: Malassezia species were detected in 9 [64.2%] of specimens. The most commonly isolated species were M. globosa [22.2%] and M. furfur [22.2%]. M. sympodialis, M. obtusa, M. pachydermatis, M. restricta and M. slooffiae were isolated in a rate of 11.1% each, by nested tFLP. Some discrepancies were noted when the molecular methods were compared with the phenotypic method of identification

Conclusion: From these findings it was suggested that this specific amplification may facilitate the rapid and direct identification of Malassezia species from skin scales