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The aim of our study was to evaluate a frequency of isolation and susceptibility to antibiotics of Streptococcus pneumoniae penicillin resistant among 154 strains S. pneumoniae isolated between 2003 and 2006 in University Hospital of Dr. A. Jurasza in Bydgoszcz. Antimicrobial susceptibility was assessed by disc-diffusion method according to the guidelines of Clinical and laboratory Standards Institute and The national Reference Centre for Antimicrobial Susceptibility. Minimal inhibitory concentrations for penicillin and cefotaxime were assessed by E-test method. Study shows increasing isolation of SPPR strains from 8,2% in 2003 to 32,0% in 2006. Strains were mostly isolated from patients ofNeurosurgery and Neurotraumatology Clinic and Rehabilitation Clinic. SPPR strains were mainly isolated from respiratory tract. Over 68% of SPPR showed intermediate resistance to penicillin and 73,3% of strains were susceptible to cefotaxime. Between 2003 and 2006 increased percentage of resistance strains to erythromycin, tetracycline and sulphometoxasol.

The phage types of 78 S. aureus strains isolated from nose swabs obtained from a medical students in 2005 -2006 was determined and antibiotic resistance of the phage types was analysed. 680 students were tested in order to obtain the strains and 11.5% of them were carriers of S. aureus. Phage typing was performed using basic set of23 phages and 3 additional phages: 88, 89 and 187. Drug resistance was determined by the disc-diffusion method. The most frequent in studied population were the group III (21.8%) and strains lysed by phages belonging to varied groups (21.8%). Highly different phage patterns were observed among strains belonging to each of the group. Strains belonging to the group III as the strains lysed by phages from varied groups were most frequently resistant only to penicillin (52,9% respectively). Resistance to penicillin was also most often observed in the strains belonging to another groups and phage types. Usefulness of the additional phages 88,89 and 187 was in the investigations as no more than 51% of strains was lysed by this phages.

Phenotype and genotype identification of 179 Neisseria meningitidis strains isolated from cerebrospinal fluid or blood of patients with meningococcal infection, hospitalized in Poland, was performed. This is the first analysis of that type conducted in Poland. We analyzed strains collected in 1995-2000 from laboratories located all over the country. Phenotype Neisseria meningitidis B:22:P1.14 was the predominant among analyzed invasive strains in Poland. Type 22 is characteristic to most of the strains isolated in our country. No strain from analyzed group belonged to known epidemic clusters. One penicillin resistant strain (MIC = 2 mg/l) and about 27% strains with decreased susceptibility to penicillin (0.1 = < MIC < 1.0 mg/l) were present among 166 N. meningitidis tested. All strains were susceptible to ciprofloxacin and rifampicin.

In mixed cultures of staphylococci a transfer of the resistance to methicillin and penicillinase plasmids as well as tetracycline and chloramphenicol plasmids was investigated. It was shown that the resistance to methicillin was transferred in mixed cultures from one strain of S. aureus to another and from S. epidermidis to S. aureus. In both cases transfer of methicillin resistance required, the presence of penicillinase plasmid in recipient or donor strain. In the case of other markers transmission was independent. Moreover it was shown that the transfer of resistance genes in mixed cultures was mediated by bacteriophage of the serologic group A.

The studies aimed at analysing the resistance to some beta-lactam antibiotics among E. coli and K. pneumoniae clinical isolates and at evaluating. The extended spectrum of beta-lactamases (ESBL) production in the isolates. The analysis included 137 E. coli strains and 52 K. pneumoniae strains, isolated from hospitalized patients and out-patients treated in the first trimester of 1998. The strains were identified using the ATB computer system. Antibiotic sensitivity of the isolates was determined by disc-diffusion tests. ESBL production capacity of E. coli and K. pneumoniae strains was estimated by double-disc and ATB BLSA tests. Most of the analysed E. coli strains were found to exhibit significant sensitivity to compound penicillin preparations containing beta-lactam inhibitor (Augmentin, Tazocin) and to the third generation cefalosporins, in contrast, K. pneumoniae strains much more frequently were resistant to the drugs. Among the obtained isolates, 3 (2.2%) E. coli strains and 21 (40.4%) K. pneumoniae strains produced ESBL but all the isolates proved sensitive to imipenem. In evaluation of ESBL production-detecting tests, the double-disc test was found to be more reliable than ATB BLSA test.

Streptococcus pneumoniae strains are exhibiting increasing rates of antibiotics resistance. A rapid increase of resistance was seen not only to penicillin but also other antimicrobial agents and therefore this paper describes the study of resistance and multiresistance of pneumococci to 7 antibiotics: penicillin (P), erythromycin (E), clindamycin (CC), tetracycline (T), co-trimoxazole (SXT), cefotaxime (CTX) and vancomycin (Va), using the disk-diffusion technique according to NCCLS procedure. We tested a total of 218 S. pneumoniae strains isolated from various materials: from sputum (54), noses (117), throats (28) and different swabs specimens (19). The overall percentage of resistant isolates to penicillin was 3.7%, to erythromycin--4.1%, to clindamycin--10.6%, to tetracycline--17.4%, to co-trimoxazole--15.6%, to cefotaxime--2.3%. In the sputum was most the monoresistant strains (66.7%). The multiresistance was highest in the penicillin resistant pneumococci. With the exception of vancomycin, the number of resistant strains to non-beta-lactam antibiotics (erythromycin, clindamycin, tetracycline, co-trimoxazole) was higher in penicillin-resistant strains compared with penicillin susceptible isolates. All isolates were susceptible to vancomycin.

Staphylococcus aureus is a very important pathogen in humans about 20% of all bacterial infections are caused by S. aureus. Because the staphylococcal sensitivity patterns have changed, the aim of this study was to investigate the current susceptibility of the S. aureus strains to 9 antibiotics: penicillin (P), amoxacillin/clavulanic acid (AMC), erythromycin (E), cortimoxazole (SXT), tetracycline (T), chloramphenicol (C), mupirocin (MUP), gentamicin (Ge) and vancomycin (Va). Susceptibility testing was performed by disc diffusion technique, by the procedure outlined by the National Committe for Clinical Laboratory Standards (NCCLS). Susceptibility to methicillin was determined using 5 micrograms methicillin disks. beta-lactamase production in the penicillin-resistant strains was detected with nitrocefin impregnated disk (Cefinase, BBL Microbiology system). The microbiological characteristics of the samples: 338 of the isolates were derived, from noses and the throats 382--from surgical wound secretions. The analysis of the results showed that most S. aureus strains (82.8%) are penicillin resistant and beta-lactamase producing 13.5% of all strains were methicillin-resistant. 16.5%--were erythromycin resistant; 3.2%--were cotrimoxazole resistant; 51.4%--were mupirocin resistant; 20.6%--were gentamicin resistant. All of the strains were vancomycin sensitive.

On the basis of vaginal secretion cultures in 520 pregnant women admitted for labour, the susceptibility to drugs was studied of bacteria present in it. Four basic antibiotic groups were taken into account: penicillin derivatives, tetracyclines, aminoglycosides, cephalosporins. A higher resistance to the studied drugs was found of Gram (+) than Gram (-) bacteria, while the highest susceptibility was found to cephalosporins, and the lowest to aminoglycosides. Of interest was the high sensitivity of microorganisms to penicillin derivatives, which is of significant importance in view of their slight side effects and relatively low treatment cost.

The investigation was performed on 923 strains of S. aureus isolated from clinical material obtained from several regions of Poland. Resistance to methicillin was tested by a dilution method on a solid Mueller-Hinton medium supplemented with 2% of NaCl. Strains exhibiting MIC higher than 4 micrograms/ml were determined as resistant. Resistance to other antibiotics (P, Am, CB, CF, CH, MA, Ge, Bs, E, L, Dx) was tested by a disc method. Bacteriophage typing of S. aureus was performed by a method described by Blair and Williams in RTD and RTD x 100, using basic set of phages and additional phages (88, 89, 187). MRSA were present in various regions of the country with similar frequency (from 3.3% to 8.3%). In one center only the percentage was as high as 52.3%. High percentage of MRSA was noted in burned patients (59.9) and these strains were obtained at one center. Within the MRSA III phage group was dominating as well as non-typable strains and inhibited at 100 x RTD-35.4%. MRSA most frequently were typing with phages 88-40.9%, 89-35.0%, 85-24.0%, and they rarely belonged to the phage group II. Among MRSA strains higher percentage of antibiotic-resistance was noted, as compared with other strains. About 60% of MRSA strains were resistant to 6-8 antibiotics. The dominating resistance concerned penicillins, cephalosporins, aminoglycosides, tetracyclines and erythromycin.

Methicillin-resistant strains of Staphylococcus aureus (MRSA) constitute a serious diagnostic and therapeutic problem. Over 500 strains of Staphylococcus aureus were tested for susceptibility to methicillin. By application of a screening method, 13.7% of these strains were classified as methicillin-resistant. Over 95% of these strains were isolated from hospital infections. Applying criteria of belonging of these strains to methicillin-resistance classes it was found that 49.3% belonged to class II, 31.2% to class III and 19.5% to class IV. Analysis of susceptibility to antibiotics of MRSA strains demonstrated significant differences between class II and between class III and IV in resistance to imipenem, gentamycin, erythromycin and tetracycline. All tested strains were susceptible to ciprofloxacin, ofloxacin, vancomycin and teicoplanin. The screening method (25 mg methicillin/l of TSA medium) results in obtaining of univocal results of determination of methicillin-resistance in S. aureus.

Whole cells or isolated membranes of Streptococcus pneumoniae were treated with labelled benzyl penicillin and the penicillin binding proteins (PBPs) were visualized by fluorography after SDS-PAGE electrophoresis. The PBP profiles obtained for strains sensitive and resistant to penicillin strongly differed depending not only on the concentrations of acrylamide and bis-acrylamide used in the separating gel but also on the batch used (different manufacturers). The latter was also true for sodium dodecyl sulfate.

Beta-lactamase-positive gonorrhoea was rather sporadic in Poland. In spring 1988 a marked rise was observed in the proportion of therapeutic failures in the treatment of gonorrhoea with procaine penicillin (4.8 million u) with probenecid among patient treated in the outpatient clinic of the Venereology Institute in Warsaw. The cause was infection with beta-lactamase producing gonococci. Up to June 1989 beta-lactamase production ability was tested in gonococci cultured from 415 patients (363 men and 52 women) with positive results in 73 cases (61 men and 11 women) that is in 18%. Most (85%) patients were treated with spectinomycin (2 g intramuscularly in men and 4 g in women in one dose) with cure in all cases. Treatment with tetracycline (2 g daily for 7 days) given to 12 patients failed in 2 cases. These results, if confirmed in other parts of the country, will cause the necessity of revision of the presently accepted indications for gonorrhoea treatment with penicillin with probenecid as the basic method.

Potassium penicillin G was administered intravenously 4 times daily in doses of 6 million u for 10 days to 49 patients, 36 with central nervous system syphilis and 13 with latent seroresistant syphilis. Forty six patients were followed up after treatment. In 16 patients with central nervous system syphilis treated by this method another cerebrospinal fluid examination was done. Cerebrospinal fluid changes regressed completely in 13 patients, in three cases the improvement was incomplete. The titres of VDRL and FTA tests decreased in 23 patients with central nervous system syphilis and in 11 with latent seroresistant syphilis. In eight patients treated by this method seroresistance persisted and in four cases the titre fluctuated. The results of the study demonstrate the effectiveness and advantages of the treatment of central nervous system syphilis and latent seroresistant syphilis with crystalline penicillin administered intravenously.