[Corynebacterium imitans isolated from blood culture in a patient with suspected bacteremia - the first isolation from human clinical material in the Czech Republic].

The current view of the clinical importance of nondiphtherial corynebacteria recovered from human clinical material has changed considerably in recent decades; in many cases, a direct etiological role is assumed or has already been demonstrated. Presented is a case of suspected bacteremia in a hospitalized elderly woman with isolation of the very rare species Corynebacterium imitans from blood culture. However, the etiological significance of the isolated microorganism remains unclear. The aim was not to demonstrate the etiological significance of the isolated C. imitans strain but to report the occurrence of this very rare species which is considered to be the first isolation from humans in the Czech Republic.

[Antibiotic resistance in nontyphoidal salmonellae serovars in the Czech Republic]. / Antibiotická rezistence u netyfových sérovaru Salmonella spp. v Ceské republice.

STUDY AIM: To determine antibiotic resistance and incidence of multidrug resistance among Nontyphoidal salmonellae serovars isolated from humans. MATERIAL AND METHODS: Consecutive Salmonella isolates from patients, recovered in 48 microbiology laboratories in May 2012, were analyzed in the respective reference laboratories at the National Institute of Public Health. Strains were re-identified and differentiated into serovars. Their minimum inhibitory concentrations (MICs) to 11 antibiotics were determined by the microdilution method. RESULTS: Of 25 serovars identified among 637 strains of Salmonella enterica, the most frequent were Enteritidis (87.0 %), Typhimurium (4.9 %), and monophasic Typhimurium 4,[5],12:i:- (2.0 %) and Mbandaka (0.6 %); other serovars were rare. Altogether 558 strains (87.6 %) were susceptible to all antibiotics tested and the remaining 79 strains were resistant to one or more antibiotics. The prevalence rates of resistance to individual antibiotics among 637 study strains were as follows: ampicillin 8.5%, tetracycline 5.7%, sulfamethoxazole 5.2%, cipro-floxacin 3.8%, and chloramphenicol 2.5%. Resistance to gentamicin, trimethoprim, and third and fourth generation cephalosporins was rare ( 0.5%) and none of the study strains showed resistance to meropenem. Three producers of extended spectrum beta-lactamase were multidrug resistant and two of them recovered from twins exhibited a different pattern of resistance. Resistant strains were most often assigned to the following serovars: Enteritidis (49.4%), Typhimurium (26.6%), and monophasic Typhimurium (15.2%). While only 7% (39 of 554 strains) of Enteritidis strains were resistant, the serovars Typhimurium and its monophasic variant 4,[5],12:i:- showed high rates of resistance, i.e. 66.7 and 92.3%, respectively. Furthermore, resistance was revealed in all strains of the serovars Virchow (n = 3), Kentucky (n = 1), and Newport (n = 1), in two of three strains of the serovar Infantis, and in one of two strains of the serovar Stanley. All five blood isolates were assigned to the serovar Enteritidis and one of them showed resistance to ciprofloxacin. Of 79 resistant strains, 26.6% showed resistance to ampicillin only and 24.1% to ciprofloxacin only, with multidrug resistance, i.e. resistance to three or more antibiotics, confirmed in 43.0% of strains. CONCLUSION: Despite a relatively low prevalence of resistance to the antibiotics tested among 637 study strains, the following alarming findings were made: Detection of Salmonella enterica strains resistant to ciprofloxacin as the drug of choice or to higher generation cephalosporins and multidrug resistance revealed in two thirds of the strains of the serovar Typhimurium and in all but one strains of its monophasic variant 4,[5],12:i:-.

Global phylogeography and evolutionary history of Shigella dysenteriae type 1.

Together with plague, smallpox and typhus, epidemics of dysentery have been a major scourge of human populations for centuries(1). A previous genomic study concluded that Shigella dysenteriae type 1 (Sd1), the epidemic dysentery bacillus, emerged and spread worldwide after the First World War, with no clear pattern of transmission(2). This is not consistent with the massive cyclic dysentery epidemics reported in Europe during the eighteenth and nineteenth centuries(1,3,4) and the first isolation of Sd1 in Japan in 1897(5). Here, we report a whole-genome analysis of 331 Sd1 isolates from around the world, collected between 1915 and 2011, providing us with unprecedented insight into the historical spread of this pathogen. We show here that Sd1 has existed since at least the eighteenth century and that it swept the globe at the end of the nineteenth century, diversifying into distinct lineages associated with the First World War, Second World War and various conflicts or natural disasters across Africa, Asia and Central America. We also provide a unique historical perspective on the evolution of antibiotic resistance over a 100-year period, beginning decades before the antibiotic era, and identify a prevalent multiple antibiotic-resistant lineage in South Asia that was transmitted in several waves to Africa, where it caused severe outbreaks of disease.

Species identification of strains belonging to genus Citrobacter using the biochemical method and MALDI-TOF mass spectrometry.

Strains of genus Citrobacter (152 isolates from 1950 to 1988 deposited in the Czech National Collection of Type Cultures, Prague) were re-classified using biological and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) methods. One-hundred thirty-six strains (ca. 90 %) were identified to the species level using the biological method with evaluation by Farmer matrix. MALDI-TOF MS exhibited better identification capability, the data being more compact; the method was unambiguously successful in typing 145 (95 %) strains. Comparison of the results of identification by the two methods revealed differences (for 12 samples) in identified species which, considering all biochemical and/or MS characteristics, could be attributed to the natural variability of strains and close relation of the misidentified species (all of them belonged to the Citrobacter freundii complex). Taking into account all the above data, both methods can be considered reliable; however, the MALDI-TOF MS exhibits higher accuracy, efficiency, and rapidity.

Pleomorphic conidiation in Claviceps.

Types of asexual sporulation in 17 Claviceps species and the closely related Corallocytostroma ornicopreoides were revised in relation to the phylogeny of clavicipitaceous fungi. We observed: (1) enteroblastic conidiation from branched phialidic conidiophores typical of the genus (anamorph Sphacelia) in all species including Corallocytostroma; (2) widespread and often sequential formation of terminal holoblastic secondary conidia on tapering hyphae arising from sphacelial macroconidia: and (3) in addition to sphacelial conidiation, sympodial holoblastic conidiation of the Ephelis-type in cultures of C. zizaniae and in both the culture and sphacelial tissue of C. citrina. Secondary conidiation was not found in C. purpurea, C. citrina and C. sorghicola. During sphacelial fructification, most species produced macroconidia and microconidia. Only macroconidia formed in planta underwent secondary conidiation whereas microconidia did not germinate at all. In C. phalaridis, the formation of holoblastic 2-3 celled appendaged conidia was observed, similar to that of Aciculosporium and Neoclaviceps. In dendrograms based on ITS1-5.8S rDNA-ITS2 sequences, genera and species with appendaged conidia grouped on a highly supported clade with ancestral Corallocytostroma. The clade was placed inside a group of tropical species of Claviceps, without any relationship to Balansiae.

Ergot alkaloids produced by submerged cultures of Claviceps zizaniae.

Two ergopeptine alkaloids, alpha-ergocryptine (1) and its C(8) epimer alpha-ergocryptinine, have been isolated from the mycelium and fermentation broth of submerged cultures of Claviceps zizaniae CCM 8240. The structure of 1 was determined by HPLC/positive ion APCI MS and NMR analysis. Alkaloid concentrations of 10 microg/mL in 14-day-old fermentation broth and 1 mg/g of dry mycelium mass were found. These results are of considerable biotechnological interest since these were the only detectable alkaloids produced. Toxicity of naturally occurring sclerotia of C. zizaniae cannot be excluded.