[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:-.

[Nocardia farcinica as the causative agent of a brain abscess in a patient with interstitial lung disease]. / Nocardia farcinica jako puvodce abscesu mozku u pacienta s intersticiálním onemocnením plic.

This case report describes a two-step protocol for the identification of the causative agent of nocardiosis in a patient with brain abscess, antibiotic susceptibility testing and etiological treatment after neurosurgery. The patient treated with corticosteroids for pulmonary fibrosis and presenting with multiple neurological manifestations was admitted to a neurosurgery clinic. CT and contrast MRI revealed an expansive multilocular lesion 45 x 35 mm in size in the left parietal lobe, differentially diagnosed as malignant glioma. The lesion was biopsied and the histology showed a brain abscess containing white blood cells and dead tissue. The aspirated pus culture yielded bacteria of the genus Nocardia that were further identified, in the first step, by phenotypic methods (Gram positivity, partial acidoresistance, airborne mycelium detection, growth at 45 degrees C, lysozyme resistance and antibiotic resistance phenotype) as belonging to resistance phenotype V., v.s. N. farcinica (resistance to aminoglycosides except amikacin and to third-generation cephalosporins). In the second step of the polyphasic identification, rDNA was isolated and a 1000 bp part of the 16S rRNA gene was sequenced. Sequence comparison with the GenBank database using BLAST software identified the agent as N. farcinica (100%). The isolate was tested for susceptibility by the NCCLS /CLSI dilution method and showed good susceptibility to co-trimoxazole, amikacin and imipenem. The patient was treated with long-term intravenous cotrimoxazole acid in combination with amikacin and his clinical condition and laboratory parameters of inflammation improved. N. farcinica is among the three most frequently isolated Nocardia species in Europe as well as in the Czech Republic where it was repeatedly recovered from the lungs and respiratory tract of immunocompromised patients with systemic nocardiosis.

[The use of molecular genetics techniques in clinical microbiology--final report from the workshop of the Molecular Microbiology Working Group TIDE]. / Aplikace metod molekulární genetiky v klinické mikrobiologii: zpráva z jednání Pracovní skupiny molekulárni mikrobiologie--TIDE.

In the last decade, there has been a rapid development in the use of molecular genetics methods in clinical microbiology. Novel technologies bring new knowledge and approaches to various disciplines of microbiology--taxonomy, identification of microbes, clinical diagnosis, epidemiology of infectious diseases and antibiotic resistance. This article summarizes the conclusions from the workshop of the Molecular Microbiology Working Group TIDE held during the Second Annual Meeting of the Society for Medical Microbiology of the J. E. Purkyne Czech Medical Association.

[Filamentous "contaminants" in the mycobacteriology laboratory; their culture, identification and clinical significance]. / Vlálmoté "kontaminanty" v mykobakteriologické laboratori, jejich kultivace, identifikace a klinický význam.

Frequent "contaminants" detected during mycobacterial culture of decontaminated samples are bacteria of the order Actinomycetales. These are usually bacteria classified as the family Corynebacterineae, genera Corynebacterium, Dietzia, Gordonia, Nocardia, Rhodococcus and Tsukamurella. These bacteria frequently colonize the airways and, under certain circumstances, they may cause life-threatening diseases. In severely immunocompromised patients, they regularly cause life-threatening infections with bacteria of the genus Nocardia. These filamentous bacteria, developing aerial mycelium in the culture, are partly acid-resistant and resistant to lysozyme. They cause nocardiosis, a rare but serious disease in patients with various types of immune deficiency. Differential diagnosis must distinguish between the genera Streptomyces, Actinomadura and Nocardiopsis and other soil saprophytes that are not acid-resistant, sensitive to lysozyme and faster growing. They frequently colonize the airways of patients with lung disease but very rarely cause diseases. The diagnosis of aerobic actinomycetes and determination of their sensitivity to antibiotics are problematic since they grow longer, are difficult to stain and are involved in atypical biochemical reactions. Precise identification of the genera and species requires polyphasic identification of isolates using molecular microbiology methods. If diagnosed early, infections caused by aerobic actinomycetes are easy to treat with targeted antibiotic therapy.

Untraditional glucose fermenting actinomycetes as human pathogens. Part II: Rothia dentocariosa as a cause of abdominal actinomycosis and a pathogen for mice.

Rothia dentocariosa was proved as a primary pathogen for man in the case of abdominal infection of a 19 year old woman. Clinical findings were typical for actinomycosis and the patient was cured with penicillin following surgery. Actinomycotic granules were proved by direct microscopy in the pus and R. dentocariosa was recovered as a single pathogen according to the microscopy. Two morphologically distinct isolates recovered from primocultures were described. They were studied separately and finally they were recognized as physiologically identical varieties of a single organism. In addition, the two morphological varieties of R. dentocariosa were considered to represent a particular kind of variability of the A-N type. The isolated germ was found to be pathogen for mice. Intraperitoneal infections provoked multiple nodules formation which were grown into the internal organs of experimental animals. The nodules were encapsulated and tended to spread without regard to the natural tissue plan. They contained pus involving microgranules of viable germs. This first report of the natural human infection caused by R. dentocariosa is the precedent for the definite establishing of this aerobic glucose fermenting actinomycete amidst the untraditional potential pathogens of human actinomycosis.

Untraditional glucose fermenting actinomycetes as human pathogens. Part I: Actinomyces naselundii as a cause of abdominal actinomycosis.

Actinomyces naeslundii was proved as a primary pathogen in the case of a fulminant abdominal infection of a 74 aged woman. The preliminary diagnosis of actinomycosis based on direct microscopical findings of microgranules in the pus was confirmed by the results of cultivation and casuistry in addition. The case was of a typical course for actinomycosis and penicillin following surgery was of life saving effect for the patient who was dismissed asymptomatic after 55 days of hospitalization. Actinomycotic microgranules were demonstrated in the pus from the natural infection and from experimentally infected mice and the causative agent Actinomyces naeslundii TR 91/67 was defined. Nevertheless it was concluded that the judgment of the pathogenicity of Actinomyces naeslundii and of the other members of the heterogenous group of etiological agents of human actinomycosis still remains a matter of delicacy in any actual case of their isolation. In practice however, the presumption of actinomycotic etiology of an actual infection may be supported in retrospect by the dramatical effect of penicillin without regard to the presence of concomitant microflora not necessarily sensitive to penicillin.