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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.

Faecal samples were investigated from 948 children hospitalized with the diagnose of acute intestinal infection. The authors studied the isolation and properties of a broad spectrum of microorganisms from children's faeces: Salmonella, Shigella, E. coli, S. aureus, rotaviruses, Klebsiella, Morganella, Proteus. As a result, laboratory criteria were formulated of diagnosing in children intestinal infection of staphylococcal etiology.

During the last 10 years, reinfusion of UV-irradiated blood has been rediscovered again as a therapeutic method suitable in the treatment of a variety of diseases. The described series of model experiments on rabbits confirm its beneficial effects in the treatment of staphylococcal infection: the control animals reinfused blood not exposed to UV radiation died all within 48 hours after injected with a suspension of live Staphylococcus aureus culture; all rabbits reinfused UV-irradiated blood (2 ml per kg body weight) survived the whole period of observation (30 days); reinfusion of UV-irradiated blood in a volume reduced to 1 ml.kg-1 body weight prolonged the animals' life-span to 96 or 120 hours.

Blood serum and urine samples collected from a group of volunteers treated with single doses of ampicillin and aminoglycoside preparations given separately or in combination were tested for their antimicrobial activity against the reference strains Staphylococcus aureus SZK 76/69 and ATCC 6538, Pseudomonas aeruginosa SZK 444 and SZK 385, and Escherichia coli SZK 326/71. Out of all antimicrobials and their combinations tested the most powerful was the combination of netilmicin with ampicillin. Of the therapeutic combinations used nowadays in clinical practice the combined use of gentamicin and ampicillin proved also effective. These antibiotic combinations appear thus to be best suited for the treatment of mixed Pseudomonas aeruginosa and Staphylococcus aureus infections and of urinary tract infections caused by bacterial strains exhibiting in the in vitro susceptibility assays a reduced sensitivity to some of the antibiotic preparations used.

Studies were made on the morphological variety in plaques produced by phage lysis and autoplaques in Pseudomonas aeruginosa strains. The great variability of phage plaque morphology may lead to a confusion with the autoplaques produced spontaneously by P. aeruginosa strains. The production of autoplaques is characteristic of a large number of clinical strains of P. aeruginosa. The appearance of autoplaques may complicate analysis of significant clinical strains of P. aeruginosa.

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.

In artificial pseudomonas infections undertaken on white mice the effectiveness of the aminoglycosides (gentamicin, tobramycin, netilmicin, amikacin) was compared. The most effective drugs on highly susceptible Ps. aeruginosa were amikacin and netilmicin. Moreover amikacin is probably capable of inhibiting pseudomonas toxin production. Therefore this preparation should be left in reserve for the treatment of serious pseudomonas processes.

The protective, therapeutical and bactericidal effects of hyperimmune antilysin serum was studied. The sera anti I II III and II III were found to be most effective. Active immunization also confirmed pronounced immunogenic effects of haemolysins I II III and II III.

A comparative experimental study was carried out of antigenic staphylococcal preparations developed in the USSR and Czechoslovakia for the immune therapy of chronic staphylococcal infection. The efficiency of the preparations was unequivocally confirmed using the rabbit staphylococcal sepsis model. The immunogenicity of tested strains was shown not to always correlate with their virulence. Preparations obtained by means of aqueous extraction from mildly virulent immunogenic strains exhibited greater protective activity than those prepared from highly virulent strains. The PCA phenomenon did not differ significantly provided the tested preparations were administered at doses which ensured equal protective action.

Hospital infections are of a major and growing health concern worldwide. They are the cause of appreciable economic loss, but what raises the particular alarm, both ethically and as a public health problem, is their continuous trend towards increasing lethality. The incidence of nosocomial infections can be prevented by creating a system of barriers that would interrupt their spread and transmission. Apart from strict adherence to general hygiene rules and the rational employment of examination methods it is essential in this respect that a prime attention is paid to the sensible use of antimicrobials, i.e. the persuance of a sound antibiotic policy. Its integral components are the systematic laboratory control, continuous epidemiological surveillance of bacterial drug resistance patterns, study of variations in the biological properties of multiple resistant bacterial strains, and the development of, and adherence to, effective and indicated treatment schedules. The particular problems related to bacterial enzyme activities and the genetic information (plasmids) coding for resistance to antimicrobials, as well as the virulence and pathogenicity of agents responsible for the onset of hospital infection are also discussed in this context. It is pointed out that for an effective hospital infection control it is essential to avoid the onesided pressure of badly applied antibiotic therapy.

Antibody response to antibiotics in patients with chronic staphylococcal diseases was studied and the results were compared with the production of specific antibodies. Increased titres of antibodies to antibiotics were found in cases with inadequate antibody response. The possibility of an immunosuppressive effect of antibiotics on the formation of specific antistaphylococcal antibodies is discussed.

Pseudomonas aerugionsa phages F 116 and G 101, propagated on ML 4262 strain into which gentamicin-tobramycin resistance determinants have been increased by means of conjugation, from wild-type strains Vy 28, 29 and 34, were capable to transduce R determinants to PAO 1670 strain. Transfer ability was co-transduced as well, with exception of transductants selected with streptomycin. "Autoplaque formation" ability, occurring in original wild-type strain Vy 28, could be co-tranduced with all tobramycin-resistant determinants by F116 but not G 101 phage.

Acute pseudomonas infections require treatment with antibiotics producing a bactericidal effect. The most useful are gentamicin, tobramycin, sisomicin and polymyxin B. In resistant strains, amikacin is indicated in addition. Carbenicillin, ticarcillin, carfenicillin or azocillin should never be given alone but in combination with some of the above preparations. Other drugs, such as chloramphenicol, tetracycline or streptomycin, though effective in vitro, should be avoided. Chemotherapy may be complemented by passive immunization either with hyperimmune specific gama globulin or hyperimmune plasma. A programmatic item of combined treatment is active immunization, especially with toxoid vaccine. Chronic processes are not, perhaps with the exception of urinary infections, suitable for antibiotic therapy. For this reason effective polyvalent vaccines should be developed from appropriate strains. It is now certain that in infections caused by mucous strains (most frequently encountered in cystic fibrosis) the vaccine should be prepared from these strains, since they have distinct functional and antigenic characteristics.

Continuous surveillance of the antimicrobial susceptibility patterns of strains of Haemophilus influenzae (H. i.) is part of a routine surveillance of bacterial sensitivity to antibiotics. In this study a major attention was given to the clinically important antimicrobials used in the treatments of H. i. infections, namely ampicillin, chloramphenicol and some cephalosporin preparations. Antimicrobial susceptibility determinations carried out in 1983 and before on H.i. strains isolated in different Czech regions show a clear-cut tendency towards the higher incidence of strains resistant to ampicillin and its derivative amoxycillin. The rise in resistance to erythromycin was also observed. Susceptibility to chloramphenicol continues to remain unchanged. Of the cephalosporin antimicrobials tested (cephalothin, ceftriaxone, cefaperazone, cefsulodine and cefadroxil) the most active were ceftriaxone and cefaperazone. The need of a further continuation of surveillance of H.i. drug susceptibility patterns is strongly emphasized; to ensure effective treatment results antibiograms should be done in each case of H.i. infection.

A method of determining antibodies by their adsorption on large-pore or surface immunosorbents with subsequent treatment of the carrier with anti-immunoglobulin serum and antiphage serum isologous to the antibodies and then with the bacteriophage, has been presented. The adsorbed virions are split off by means of papain-induced hydrolysis of the antibody complex. The antigens are determined by the reaction of phage fixing inhibition. The method permits to determine small amounts of antibodies to proteins, haptenes and cells with objective calculation of results.

From incubators and children in a premature-born unit, a number of red-pigmented Ps. aeruginosa strains, resistant to kanamycin, streptomycin and lividomycin and producing haemolytic toxin II, were isolated and investigated for transfer of resistance in mixed cultures. Streptomycin, kanamycin and lividomycin resistance was co-transferred, from some strains, together with the ability of toxin production. Transfer ability was also co-transferred which might have genetic as well as epidemiological significance. Strains do produce "Autoplaques" and transferability of this property as well as of lysogeny is under investition.

Although the preponderant majority of gonococcal strains is belonging to the most susceptible micro-organisms in respect of the action of antibiotics, certain variations of sensitivity which might be of importance not only for the genetics of microbes, but also for biochemistry and, above all, for therapy may occur also among them, perhaps as a consequence of along-time pressure by antibiotics. In a preceding study (J. Hyg. Epidem. Microb. Immunol. (Prague) 12,296, 1968), the authors analyzed the situation in Czechoslovakia from 1957 to 1967 by means of 911 strains of N. gonorrhoeae isolated from male patients suffering from gonorrhoea. It was also pointed out that there was a certain tendency towards reduced efficacy of penicillin G and a presence of streptomycin-resistant strains. In later years, the studies were extended to include also strains isolated from female patients and sensitivity to some more modern antibiotics was tested. In the present report, a survey is given of the state of antibiotics resistance among gonococci in Czechoslovakia in a chronological order of 17 years which is intended to serve as a basic information for those who are dealing with this subject.

The semisynthetic penicillin suncillin was compared in vitro with carbenicillin for its effectiveness against different P. aeruginosa strains and for stability in solution. Carbenicillin was about twice as effective against the strains employed, while suncillin maintained its activity in saline for a longer time. The induction of resistance to suncillin was accompanied by the simultaneous development of resistance to the other antibiotic.

Aminoglycosides and cephalosporins belong among antimicrobials with a pronounced effect on most gram-negative rods. In vitro susceptibility and resistance to gentamicin, tobramycin, amikacin, netilmicin, cefoxitin, cefotaxime, cefsulodin, cefoperazone in Klebsiella pneumoniae, Enterobacter spp., Proteus mirabilis, Escherichia coli and Pseudomonas aeruginosa was tested by the quantitative dilution micromethod. Selected, highly susceptible strains of the above species were furthermore compared for minimal inhibitory concentration (MBC) and minimal bactericidal concentration (MBC) values. Aminoglycosides tended to be the most effective drugs for susceptible strains. In view of their relative toxicity possibly optimal combinations of individual aminoglycosides with individual cephalosporins are discussed.

Over the period 1983-1985, investigators from the Institute of Hygiene and Epidemiology, Prague, and the Central Research Institute of Epidemiology, USSR Ministry of Public Health, Moscow, carried out a joint study of drug resistance in S. aureus strains in relation to their enterotoxigenic properties and phage group specificity. Altogether 277 strains were explored which had been isolated at random from the clinical material from infant and adult inpatients. Most of the isolated strains featured multiple resistance to antibiotics: PNC (77.9%), CMP (52.7%), TET (21.6%), ERY (17.6%) and LIN (11.9%). The strains isolated from infants were most frequently resistant to TET and ERY. No correlation was found between the incidence of antimicrobial drugs resistance and toxigenic properties of the isolated strains.