Until recently the etiology of bovine spongiform encephalopathy (BSE) was considered uniform. The infectious agent was thought to be a single strain of prion (posttranslationally altered form of normal prion protein: PrPSc) retaining its biochemical and biological characteristics during interspecies transmission. However, alternate PrPSc signatures through large-scale screening have recently been detected. In addition, genetic alterations governing susceptibility to prion infection and a mutation (E211K) capable of eliciting spontaneous BSE have been demonstrated. Thus, the spectrum of BSEs have broadened and three PrPSc variants (BSE-C, BSE-H and BSE-L) are now defined. Moreover, a new condition resembling BSE, idiopathic brainstem neuronal chromatolysis (IBNC), has been described that may also turn out to be a prion disease. Since one of the new BSE variants, L-type BSE, proved highly pathogenic detection and further characterization of the new conditions are essential.
Authors:I. Damjanova, Á. Tóth, É. Kenesei, M. Köhalmi, P. Szántai, M. Füzi, and J. Pászti
Molecular epidemiology and genetic features of an extended-spectrum β-lactamase (ESBL) producing Klebsiella pneumoniae epidemic clone (KP-EC) with elevated ciprofloxacin MIC (minimum inhibitory concentration) values from multiple nosocomial outbreaks and sporadic cases between 2006 and 2008 in Hungary were investigated.
As a result of continuous monitoring of ESBL-producing KP-ECs, 27 isolates collected from five healthcare facilities were selected for macrorestriction profile analysis by PFGE (pulsed field gel electrophoresis). Of these, 12 strains were isolated from adult inpatients, while 15 strains were from newborns. The MIC values for several antibiotics were determined by agar dilution technique. Molecular typing was further performed by PCR (polymerase chain reaction) and sequencing of several antibiotic resistance genes, plasmid profile analysis, transfer of resistance determinants and multilocus sequence typing (MLST).
All isolates showed moderate resistance to ciprofloxacin (MICs ranged from 0.5 to 8 mg L−1). PFGE revealed the existence of only one genetic cluster defined as EC IV. PstI digestion of plasmid DNA revealed two highly diverse restriction patterns in “adult” and “newborn” isolates corresponding to plasmids from the Hungarian Epidemic Clone and plasmids isolated from a neonatal nosocomial outbreak in 1998, respectively. Sequence analysis of b-lactamase genes from plasmids of 14 selected isolates detected blaSHV-2a in strains isolated exclusively from newborns and blaCTX-M-15 in strains isolated exclusively from adult inpatients. MLST established that strains of the PFGE cluster belonged to a novel sequence type ST274.
ESBL-producing K. pneumoniae isolates belonging to the novel sequence type ST274 appeared in the newborn and adult hospital settings in Hungary and acquired SHV-2a or CTX-M-15 type enzymes, respectively. Thus, a new antimicrobial resistance strategy for successful conformation to distinct hospital settings was found.
Authors:Emese Szilágyi, M. Füzi, Ivelina Damjanova, Karolina Böröcz, Katalin Szőnyi, Á. Tóth, and K. Nagy
Fourteen outbreaks in Hungary between 2005 and 2008 caused by extended-spectrum beta-lactamase-producing
(ESBL-KP) were epidemiologically investigated and the isolated pathogens were characterized by molecular techniques. Ten of the fourteen outbreaks occurred in adult wards and four in neonatal units affecting a total number of 73 patients. The 54%  of the patients developed bloodstream infections and 21.9%–21.9%  pneumonia and surgical site infections, respectively. The overall rate of mortality proved high: 36.9% . Outbreaks in adults affected more patients, had higher attack rates, were more prolonged in duration and had a 6.9-fold higher mortality rate than outbreaks observed in neonates. The outbreaks in neonates were caused by SHV-type ESBL-producing klebsiellae, while in the “adult outbreaks” exclusively CTX-M-type ESBL-KP strains were involved. While the outbreak strains isolated from neonatal units could be assigned to a variety of pulsotypes, the previously described
epidemic clones, ST15 and ST147, could be identified among the pathogens causing outbreaks in adult units.
Authors:Zorica Lepsanovic, B. Libisch, Branka Tomanovic, Zorka Nonkovic, Boglárka Balogh, and M. Füzi
From the Central-East European region the first VIM metallo-
-lactamase (MBL) producing
strains were published from Croatia, Poland and Hungary. The aim of this study was to assess the contribution of MBL-production to carbapenem-resistance among
clinical isolates in the Military Medical Academy (MMA) in Belgrade, Serbia between August 2004 and September 2007. Only one
isolate with strain number 722 proved MBL-positive that harboured a novel class 1 integron with a
-like cassette in the first position, followed by
, a putative gene with unknown function. Our data indicate that MBL-producing strains occur at a prevalence of less than 1% among imipenemnonsusceptible
clinical isolates in this Belgrade hospital. The newly identified VIM MBL-producing
strain 722 could be assigned to serotype O11, and it was panresistant to all antimicrobials tested. The isolate displayed sequence type ST235 by multilocus sequence typing which is the founder sequence type of the previously identified international clonal complex CC11 that already contains
-positive isolates from Italy, Greece, Sweden, Hungary and Poland. In conclusion, this is the first report of VIM MBL-producing
from Serbia and also of the occurrence of such isolates belonging to the international clonal complex CC11 in this country.
Authors:Emese Szilágyi, M. Füzi, Karolina Böröcz, Andrea Kurcz, Á. Tóth, and K. Nagy
Risk factors for and outcomes of bloodstream infections (BSIs) caused by ESBL-producing and by ESBL-non-producing
were compared in a four-year multicenter study in Hungary. One hundred ESBL-positive and one hundred ESBL-negative patients were included as cases and controls. Investigated risk factors were related to demographics, comorbid conditions, treatments, invasive procedures, surgery prior bacteremia, presence of additional nosocomial infections and preceding hospital admission within a year. Measured outcomes were crude mortality, mortality related to infection and delay in introducing appropriate therapy (DAT). Though some risk factors for infection (admission to intensive care units, having central venous and/or urinary catheter, mechanical ventilation) were shared by both groups, in other respects cases and controls were found to differ substantially. The 36 percent of patients with BSIs with ESBL-producing Klebsiella died versus 23 percent of controls (odds ratio [OR]: 2.5; 95% confidence interval [CI]: 1.0–5.4; p = 0.02). The 18 percent of deaths in cases versus 9% in controls could be attributed to infection (OR: 5.0; 95% CI: 1.5–16.2; p = 0.006). Cases more often received previous antibiotic therapy than controls (OR: 2.7; 95% CI: 1.1–6.7; p = 0.02) and delay in the introduction of appropriate antibiotic treatment was observed in 44% of cases versus 19% of controls (OR: 3.4; 95% CI: 1.6–7.3; p = 0.001). The results demonstrate that BSIs caused by ESBL-producing
are related to previous antibiotic therapy and are associated with a high rate of mortality that is often linked to delay in the introduction of appropriate antibiotic therapy. This confirms that besides infection control measures the early identification and antibiotic resistance profiling of the infecting pathogen is salient in the control of BSIs caused by ESBL-producing