RESUMEN
Background: Pandrug resistant Gram-negative organisms [PDRGNs] have emerged, as a major threat to hospitalized patients. They have been associated with mortality rates ranging from 30 to 70%. Because of the high morbidity and mortality rates of severe pandrug resistant acinetobacter spp infections, combination therapies, as opposed to monotherapy, are suggested. A synergistic effect may be developed when antibiotics are used in combination. Through this synergistic effect, treatment efficacy can be improved and resistance can be prevented
Aim of the work: To investigate the use of in vitro antibiotic synergy test [checkerboard] for pandrug resistant acinetobacter species with a clinical feedback on the most synergistic antimicrobial combination
Materials and Methods: During this study, one hundred isolate of drug resistant acinetobacter species identified by routine culture and sensitivity using disc diffusion susceptibility test, were collected from critically ill patients admitted to Ain Shams University Internal Medicine Intensive Care Units. The isolates were subjected to: [i] Determination of MIC using Vitek 2 automated system to confirm resistance of acinetobacter species to all commercially available antibiotics, [ii] Broth micro-dilution method [BMD] for determination of tigecycline susceptibility, and [iii] Determination of antimicrobial synergy by broth micodilution [Checkerboard method]
Results: Vitek 2 system results showed that, all of the 100 isolates were resistant to all antibiotics included in the study. On the other hand, 100% of the isolates were sensitive [S] to Colistin. As regards the results by Broth microdilution antibiotic susceptibility method, all 100 isolates [100%] were resistant to ampicillin/sulbactam, meropenem and ciprofloxacin, whereas 95 isolates [95%] were resistant to amikacin, whereas all 100 isolates [100%] tested were sensitive to tigecycline. The results of the antibiotic combinations were as follows; the activity of ampicillin/sulbactam in combination with amikacin showed synergy in [48%], addition in [42%] and indifference in [10%]. The activity of ampicillin/sulbactam in combination with ciprofloxacin showed, synergy in [36%], addition in [52%] and indifference in [12%]. The activity of meropenem in combination with amikacin showed, synergy in [26%], addition in [53%] and indifference in [21%]. No antagonistic activity was detected between any of the antibiotic combinations used
Conclusion: The prevalence of XDR/PDR resistant Acinetobacter spp. was highest in blood samples [43%] followed by sputum samples [35%] recovered from critically ill patients admitted to Ain Shams University Internal Medicine Intensive Care Units. Vitek 2 system showed that, all of the 100 isolates were resistant to all antibiotics included in the study. On the other hand, 100% of the isolates were sensitive [S] to colistin. Broth microdilution antibiotic susceptibility method showed that, all 100 isolates [100%] were resistant to ampicillin/sulbactam, meropenem and ciprofloxacin, whereas 95 isolates [95%] were resistant to amikacin, whereas all 100 isolates [100%] tested were sensitive to tigecycline, indicating that acinetobacter spp. did not attain resistance to tigecycline yet. The broth microdilution antibiotic synergy test [Checkerboard method], being the reference method for assessing antimicrobial synergy, showed that the highest synergic activity belongs to ampicillin/sulbactam and amkacin [48%], and the lowest synergic activity belongs to meropenem and amikacin [26%]
RESUMEN
Background: Infections of central nervous system [CNS], such as encephalitis, meningitis, and meningoencephalitis are potentially life-threatening syndromes. They are caused by a diverse array of infectious causes. Despite being relatively uncommon, the morbidity, mortality, and costs are substantial. Of major importance are the herpes simplex virus [HSV]-2 and varicella zoster virus [VZV] in meningitis, and HSV-1 in encephalitis. Human herpes virus 6 [HHV-6] infection can induce severe encephalitis cases, particularly in immunocompromised. Human herpes viruses [HHVs] can cause CNS disease following primary infection, reactivation or recurrence
Purpose: To estimate the frequency of four common neurotropic herpes viruses: HHV-1 [HSV-1], HHV-2 [HSV-2], HHV-3 [VZV] and HHV-6 as causative agents for viral encephalitis and aseptic meningitis
Patients and Methods: The study was conducted on sixty five [65] CSF samples selected from the CSF of patients clinically diagnosed with acute encephalitis or meningitis. The samples belonged to 39[60.0%] males and 26[40.0%] females. Their ages ranged from 12 days to 62 years old. All CSF samples included in the study were subjected to white cell count, estimation of the level of protein and glucose, direct macroscopic and microscopic examination and culture on blood, chocolate and MacConkey agar plates. All samples had a CSF leukocytic count >/= 5 cells/ mm3 and all were negative for bacterial culture. Real time PCR for the following viruses: HHV-1 [HSV-1], HHV-2 [HSV-2], HHV-3 [VZV] and HHV-6 was done for each sample
Results: The results of the PCR showed that twenty six [40%] were positive: twenty two [34%] were positive for a single infection; HSV-1 was positive in seven [10.8%], HSV-2 in eight [12.3%], VZV in one [1.5%] and HHV-6 in six [9.2%] of the cases. Four [6.2%] samples showed co-infection with two viruses. VZV was common in all cases of co-infection, together with HSV-2 in two [3%], HSV-1 in one [1.5%] and HHV-6 in one [1.5%]. Thirty nine cases [60.0%] were negative for the four viruses
Conclusion: The four herpes viruses [HSV-1, HSV-2, VZV and HHV-6] tested by PCR are causative agents in 40% of the tested cases of CNS infections. The most frequently detected virus by PCR was HSV-2 followed by HSV-1. In case of encephalitis, the most frequently detected virus was HSV-1, while HSV-2 was the most frequent in case of aseptic meningitis. VZV was common in all cases of co-infections
RESUMEN
Background: quinolone resistance is traditionally mediated by chromosomal mutations mutation of DNA gyrase and/or topoisomerase IV or by the mutation of genes regulating the expression of efflux pumps, until PMQR was described in a clinical isolate of Klebsiella pneumoniae in 1998. PMQR genes generally confer low-level resistance, with their MICs falling below Clinical and Laboratory Standards Institute [CLSI] breakpoints for intermediate resistance; therefore, their contribution to quinolone resistance can be masked in strains also harboring QRDR mutations in gyrA and parC. However, their clinical significance stems from the fact that they greatly facilitate the selection of more highly quinolone-resistant strains. Although the PMQR mechanism only confers low-level resistance to FQs, its association with the occurrence of mutations in QRDR can lead to clinically relevant resistance levels. These PMQR determinants are increasingly being identified worldwide in clinical isolates of Enterobacteriaceae and Pseudomonas spp
Aim of the work: this study aimed to identify different mechanisms of fluoroquinolones resistance and determine fluoroquinolones resistance pattern among the studied isolates
Material and methods: this study was carried on 100 non duplicate clinically relevant Enterobacteriaceae and Pseudomonas spp. recovered from clinical specimens referred to Central Microbiology Laboratory, Ain Shams University Hospital for routine culture and sensitivity, aiming to 1] Determine the occurrence of plasmid-mediated fluoroquinolones resistance [PMQR] determinants by multiplex PCR and chromosomal mutations by PCR-RFLP among Enterobacteriaceae and Pseudomonas spp. in clinical specimens. 2] Identify different mechanisms of Fluoroquinolones resistance. 3] Determine Fluoroquinolones resistance pattern among the studied isolates
Results: in this study we found that 77% of FQs resistant isolates were positive to one or more plasmids, oqxAB was highest recovered PMQR among Klebsiella. 78% were positive for gyrA mutations, gyrA gene mutations were higher in Pseudomonas, Asp- 87mutation was 56/78[72%] higher than Ser-83 mutation 38/78 [49%] isolates