Search

The submitted paper deals with one of the possible aspects of the investigation of nosocomial infections, i.e. investigations of the properties of hospital strains, their importance and possible use. The incidence of bacterial hospital strains was investigated in a surgical department of a district hospital of the North Bohemian region in October 1990; at the time of the survey 29 nosocomial infections (36.1%) were revealed by the prevalence method. Bacterial hospital strains were isolated from patients with a nosocomial infection, from the attending staff and the hospital environment. The following markers were investigated: biotyping, phagotyping, serotyping, toxin production, sensitivity to antimicrobial substances and sensitivity to disinfectants. Based on results of marking of hospital strains 7 incidences with a possible epidemiological association were detected where the hospital strain of equal or very similar properties dominated. The results of the investigation confirmed the important participation of the attending staff in the spread of nosocomial infections, in particular via contaminated hands, and drew attention to shortcomings as regards adherence to the hygienic and epidemiological regime in the investigated department.

At 55 sites of a health institution in July and September 1990 a total of 161 specimens of arthropods were detected, 30 outdoors and 131 on the premises of the health institution. On their bodies 116 bacterial strains were isolated, mostly Gram-negative rods (more than 85%), in particular spp. Enterobacter, Acinetobacter, Klebsiella, Citrobacter and Pseudomonas. Gram-positive cocci accounted for cca 12%, in particular strains of S. haemolyticus and S. hominis. The greatest number of strains was detected on bodies of cockroaches, flies, Chironomus and Tenebrio. In about one third of strains the diffuse disk test revealed resistance to more than three antibiotics. The investigation was supplemented by microbiological examination of strains from a hospital environment (45 smears) and strains from biological material (82 specimens), from patients with nosocomial infections.

Main antibacterially active agents obtained from plants-Cajeput essential oil--1,8 cineol, linalool, alpha-terpineol and terpinen-4-ol, for example from Melalleuce leucadendron (Myrtaceae) as well as essential oil from Ocimum gratissimum (Labiatae) were combined in tests in vitro with selected antibiotics. Above mentioned plant products were found to be effective medicaments for local application in modern medical practice. Combinations with antibiotics potentiated their therapeutical action. On the basis of tests in vitro the synergistic action of these two kinds of medicaments, i.e., preparations traditionally used for a few last decades--antibiotics--might be well applied for therapeutical needs.

The strains of Acinetobacter calcoaceticus, var. anitratus (A. c. a.) were isolated in the nosocomial environment as an opportune pathogen. The therapy of choice may be determined after in vitro tests. Our results show following therapeutical possibilities: beta-lactam antibiotics--cephalosporins of IIIrd generation (cefotaxime), also combinations of antimicrobials have shown good results: amoxycillin or ticarcillin with clavulanic acid. Best synergistic effect was found in combination ticarcillin-amikacin.

The broad antimicrobial spectrum of Fleroxacin RO 23-6240 was tested on a panel of bacterial and several mycobacterial species. Staph. aureus strains, gramnegative bacteria E. coli, Kl. pneumoniae, Salmonella spp. were found to be rather susceptible to the tested preparation in vitro. The same was true of those species which are known to feature strong natural resistance, e.g. Ps. aeruginosa and Acinetobacter calcoaceticus. As regards mycobacteria, complete susceptibility was recorded for 10 M. tuberculosis strains, 17 M. kansasii strains and 4 strains of M. fortuitum. Only two of the eleven tested strains of the complex M. avium-intracellulare were found to be susceptible and one M. chelonae strain tested proved resistant. Due to their broad spectrum and strong bactericidal effects, chinolone preparations can be anticipated to assume an everincreasing significance in the future.

The authors studied the sensitivity of some rather recent products--flucloxacillin, doxycyclin, clindamycin and cotrimoxazol--in correlation with classical penicillin. If therapy by means of classical penicillins is unsuitable, clindamycin and the semi-synthetic penicillin flucloxacillin appear to be a further alternative and the most suitable chemotherapeutic in streptococcal infections.

Effects of a new antimicrobial agent sisomicin on microorganisms isolated from pathologic material (Pseudomonas aeruginosa, Staphylococcus aureus, Serratia marcescens, Klebsiella pneumoniae, Salmonella spp., Streptococcus pyogenes-B, Citrobacter Freundii) were studied. The results obtained were compared with another two aminoglycoside antibiotics - gentamicin and tobramycin. All three antibiotics were found to be very effective in vitro; their effect was enhanced by addition of an antibiotic of the penicillin group (carbenicillin, suncillin) or an antibiotic of the tetracyklin series (oxytetracyklin, doxycyklin). All three preparations were tested on 26 Mycobacterium tuberculosis strains. Tobramycin inhibited growth of 22 strains and thus presented the highest level of efficiency among these deoxystreptamin preparations.

Ps. aeruginosa strains--a frequement resuet of an irresponsible antibiotic therapy--represent a common agent of nosocomial infektions. At the same time, gravity of Pseudomonas diseases is also increasing. Lysogeny, bacteriocinogeny and frequent occurrence of autoplaques are the lytic manifestations of Pseudomonas aeruginosa strains which play a great role in the complexity of solving diagnostic, epidemiological end therapeutical problems connected with infections induced by these microbes. A survey is presented of the importance and utilization of the lytic properties of bacterial strains of Pseudomonas aeruginosa during the differentiation, epidemiological typing and further expansion of therapeutical possibilities in infections caused by Pseudomonas aeruginosa bacteria.

Strains of resistant species -- Staphylococcus aureus and Streptococcus faecalis -- isolated from material of nosocomial infections in the surgical department of a Prague hospital were tested for combined effect with further chemotherapeutics. The same concerned Ps, aeruginosa noted, at present, by a high degree of resistance. In Ps. aeruginosa it was the combination sisomicin-carfecillin that proved a success in 50 p. c. of cases as well as that of sisomicin-doxycyclin. At the same time the authors draw attention to the possibility of antagonistic action of the combination sisomicin-chloramphenicol in a third part of the strains tested. Potentiation of the effect in Staphylococcus aureus strains was observed also in the combination sisomicin-carfecillin in more than one half of the strains tested and in case of sisomicin-doxycyclin in one third of the strains. In Streptococcus faecalis strains sisomicin was combined with amoxycillin, carbenicillin, carfecillin and doxycyclin; synergistic action being observed with all those combinations in more than one half of strains tested. No antagonism was registered in those cases. (Ta.).

A population of 200 Y. enterocolitica strains of the serotype 03 and 100 strains belonging to other serotypes mostly, however, to the biotype 1 were examined for their sensitivity to chemotherapeutics. The serotype 03 strains were obtained from human material of diarrhoeal cases, the origin of other serotypes was various. They originated from human extraintestinal material, animals, water and foods. To summarize their results, the authors elaborated an antibiogram presented in graphs.

The authors have obtained good results in control of respiratory infections in children (aged 3-9 years) (especially those with dg. pneumonia) when applying a combination of amoxicillin with clavulanic acid. Correct indication has enabled them to shorten the period of treatment by means of this combination. The interaction of ticarcillin with some aminoglycoside preparation has been verified in vitro. Synergic action has been found to be high.