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S Pauluzzi

Publications and source records attributed to S Pauluzzi.

At least 37 records · Page 2Linked to original sources

Technical factors influencing the bactericidal activity of teicoplanin against staphylococci.

Considering 99.9% Killing after 24h of incubation, mean bactericidal activity of teicoplanin against 48 clinical isolates of Staphylococci resulted to be 67.7 micrograms/ml. Fortyfour out of 48 strains (91.7%) resulted tolerant. The high percentage of tolerant was dependent on survivors above the 0.1% allowed in several tube dilutions. Prolonged incubation consistently reduced this number. Only 37.5% of our strains remained tolerant after 48h of incubation. Bactericidal activity of teicoplanin was also significantly influenced by other technical factors. Human serum enhanced the killing of teicoplanin. For 9 strains of Staphylococcus aureus geometric mean MBC decreased from 49.9 muug/ml to 3.9 micrograms/ml (p less than 0.05); also actively growing bacteria demonstrated a higher killing rate, resulting in lower MBCs (mean 3.8 micrograms/ml). Micromethod technique was greatly influenced by the carryover phenomenon. The spot subculture technique is not accurate for bactericidal studies. A standardized technique for determining the minimal bactericidal activity is needed.

Anti-Bacterial Agents↗

Killing rate and serum bactericidal activity of oxacillin, rifampin and ciprofloxacin against Staphylococcus aureus.

The bacterial activity of oxacillin, rifampin and ciprofloxacin was examined at two concentrations by the serum bactericidal rate (SBR) technique against 5 strains of methicillin-susceptible Staphylococcus aureus. The activity of oxacillin plus ciprofloxacin and oxacillin plus rifampin was also determined for 5 strains of staphylococci examining in vitro the SBR and the serum bactericidal activity (SBA). We simulated SBR and SBA in vitro using pooled human serum containing know concentrations of antimicrobial agents. The rate at which the antibiotics kill S. aureus did not rise by increasing the concentrations over the MBC. The oxacillin-ciprofloxacin combination was indifferent when tested by the rate of killing, whereas an antagonistic interaction was frequently observed with the oxacillin-rifampin combination. The SBA was determined by two methods: the technique of the Mayo Clinic that uses Mueller-Hinton broth (MHB) as the diluent and the method of Stratton in which the diluent was prepared with MHB supplemented with Ca++ and Mg++ and combined with 50% pooled human serum. The activities of oxacillin and rifampin were decreased in the presence of human serum. These results were attributed to the high protein binding of these antibiotics. Rifampin in combination with oxacillin showed antagonism against S. aureus also by the SBA method. The inhibitory activity of drugs in combination remained substantially the same as the single more active one.

Ciprofloxacin↗

Teicoplanin in empirical combined antibiotic therapy of bacteraemias in bone marrow transplant patients.

Teicoplanin in combination with amikacin and ceftazidime was used as empirical therapy in treating 46 febrile episodes in 34 consecutive patients undergoing allogenic bone marrow transplantation. All but four of these febrile episodes occurred in neutropenic patients and 50% of them proved to be bacteraemias (23/46). Cure was achieved in 90% of Gram-positive bacteraemias (18/20) and in six of them teicoplanin was the only antibiotic with activity in vitro against the infecting strain. All (3/3) Gram-negative bacteraemias were cured. Central venous catheter removal was required in five patients (three tunnel infections, one exit-site infection and one thrombophlebitis). Two failures occurred among Gram-positive bacteraemias and in one case the patient died of infection. Four instances of side effects were documented but only one was severe (hearing loss).

Adolescent↗

Septicaemia due to gram-positive cocci in cancer patients.

Episodes of septicaemia caused by Gram-positive bacteria in five separate investigations of empirical antibiotic treatment for fever in patients with neoplastic disease have been analysed according to the antimicrobial agents administered and the outcome. The results suggest that the addition of an 'anti-staphylococcal agent', such as co-trimoxazole, vancomycin or teicoplanin, to the standard two-drug regimen (a beta-lactam antibiotic and an aminoglycoside) may be advantageous in improving the prognosis, particularly in Staphylococcus aureus septicaemia.

Adolescent↗

The behaviour of specific antibody classes in human hydatid disease.

The behaviour of IgE antibodies was investigated by the micro-ELISA method (IgE-ELISA) in patients affected by hydatidosis or in patients who had already been operated on. The results were correlated with those obtained by IgG-ELISA, IgM-ELISA, IgA-ELISA and IHA tests. In the preoperative phase the IgG-ELISA method proved to be as sensitive (80%) as the IHA test (78.5%); the IgE-ELISA method showed a good sensitivity (72.8%) with a positive rate for the IgE-ELISA/IHA of 92.7%. The IgM- and IgA-ELISA methods were of moderate sensitivity. The IgE-ELISA proved to be much more suitable than the other methods for postoperative control, since the persistence of positivity 4 years after surgery suggests the involvement of a relapse.

Antibodies↗

[Study on the presence of Cryptosporidium in Umbria].

Cryptosporidium is an intestinal protozoan parasite belonging to the same family as Isospora and Toxoplasma. Cryptosporidium can cause severe, life-threatening enteritis in immunocompromised patients; he can also cause much less severe diarrhea in immunocompetent humans and in several animal species. Cryptosporidiosis has been diagnosed by identification of characteristic cocysts in fecal smear. In order to detect the small numbers of oocysts excreted, a modified Teleman-Miyagawa concentration technique was used. After, the faecal smears were stained by means of the dimethyl-sulfoxide (DMSO) acid-fast method. During 12 months, 157 specimens of faeces of patients with diarrhoea and 75 stool samples of asymptomatic humans were examined. Cryptosporidium was identified, only, in 2 of 157 stools of patients with diarrhoea. These two patients were less than 2 years of age. Cryptosporidial oocysts not were seen in the faeces of 75 asymptomatic humans and of 35 (only 20 with diarrhoea) immunocompromised patients. Failure to detect the agent in immunosuppressed patients in likely related to poor number of examinated cases. In conclusion, routine laboratory studies to identify Cryptosporidium in the stools of immunocompromised patients seem justified, since the parasite causes in these patients severe opportunistic also extra-intestinal infections.

Adolescent↗

Viridans streptococci septicemia in cancer patients: a clinical study.

Viridans streptococci septicemia was documented in ten cancer patients, 7 of whom were neutropenic (less than 1000/mmc). Pneumonia was presumed to be the source of bacteremia in six patients. Viridans streptococci isolated from sputum culture in an immunocompromised host must be regarded as the potential etiological agent, then further characterized and checked for antibiotic sensitivity.

Adolescent↗

Treatment of infections by staphylococci and other gram-positive bacteria with teicoplanin: an open study.

Teicoplanin, 200-400 mg (3-6 mg/kg) daily iv or im, was used to treat 71 episodes of infection. The average duration of treatment was 22 days. The 64 evaluable episodes comprised 24 skin/soft tissue, 20 osteoarticular, ten urinary tract and one ventriculo-atrial shunt infections; one case of primary bacteraemia, three of endocarditis, two of pneumonia and three of pleural empyema. Fifty-five episodes were treated with teicoplanin monotherapy and nine with teicoplanin in association to other antibiotics. Overall 61% (39/64) of the evaluable infections were cured, 25% (16/64) improved and 14% (9/64) failed. Staphylococcus aureus was the most frequent pathogen, with 46 isolates. Infections by both methicillin-sensitive and resistant Staph. aureus strains showed favourable clinical and microbiological responses to teicoplanin. Side effects were observed in eight of the 64 episodes (12.5%). Bronchospasm was observed in two other cases at the beginning of therapy and the antibiotic administration was discontinued. Teicoplanin is an effective and well tolerated antibiotic for infections by Gram-positive bacteria, and it is effective against methicillin-resistant staphylococci.

Adolescent↗

Prospective randomized clinical trial of teicoplanin for empiric combined antibiotic therapy in febrile, granulocytopenic acute leukemia patients.

The increasing prevalence of bacteremia caused by gram-positive bacteria in granulocytopenic acute leukemia patients prompted us to evaluate, in a prospective randomized trial, the role of teicoplanin, a new glycopeptide antibiotic, when it was added to amikacin plus ceftazidime, as an empiric therapy of fever in these patients. Of 47 evaluable episodes, 22 were treated with the teicoplanin regimen and 25 were treated with the combination of amikacin and ceftazidime. The overall response to therapy of patients treated with teicoplanin was slightly better (82% improvement) than that obtained with amikacin plus ceftazidime (52%). The response rate of patients with gram-positive bacteremias was 80% (4 of 5) to the regimen that included teicoplanin; 25% (1 of 4) of the patients treated with amikacin plus ceftazidime responded to treatment; and for patients with gram-negative bacteremias, the response rates were, respectively, 100% (4 of 4) and 70% (7 of 10). The better results obtained with amikacin-ceftazidime-teicoplanin treatment were most evident in patients with profound (less than 100/mm3) and persistent neutropenia (83 versus 30% improvement). Furthermore, a good response rate of patients with gram-positive bacteremias (seven of eight; 87% improvement) was achieved in a small group of bone marrow transplant patients who were all treated with amikacin-ceftazidime-teicoplanin. No severe side effects were documented in any patient. Teicoplanin, as a drug administered as a single daily dose, seems to be a safe and useful anti-gram-positive agent when used in combination with amikacin-ceftazidime as an empiric therapy of febrile episodes in granulocytopenic acute leukemia patients.

Acute Disease↗

Effects of the monobactam antibiotic aztreonam on platelet function and blood coagulation.

The effects of the new monobactam antibiotic aztreonam on platelet function and blood coagulation were evaluated both in vitro and ex vivo. In the in vitro studies carried out on platelets from 6 healthy volunteers, therapeutic concentrations of aztreonam had no effect on platelet function. Aztreonam inhibited platelet aggregation only at concentrations far in excess of those clinically achievable. In the ex vivo studies carried out in 11 patients with aztreonam-sensitive infections, aztreonam, 1 g t.i.d. intravenously, did not produce any effect on platelet function and blood coagulation. We conclude that therapeutic doses of aztreonam appear not to affect haemostasis.

Adenosine Diphosphate↗

[Bacteriostatic and bactericidal activity, resistance and tolerance of 16 strains of thermophilic Campylobacter to 12 antibiotic drugs].

The majority of gastrointestinal infections due to "thermophilic" Campylobacter is self limiting and does not need antibiotic treatment. Anyhow there are some serious cases (sepsis, persistent and relapsing gastroenteritis, severe immunodeficient patients) which require appropriate therapy. The susceptibility of 15 strains of Campylobacter jejuni and of 1 strain of C. coli, isolated from patients with acute gastroenteritis, has been studied against 12 antibiotics with the broth microdilution method at two different inocula (10(3)-10(4) CFU/ml and 10(7)-10(8) CFU/ml), and with the standard agar disk diffusion test, modified to allow sensitivity testing of Campylobacter. For each antibiotic, the geometric mean of MIC and of MBC and the concentrations of the various drugs needed for inhibition and killing of 50 and 90% of the strains (MIC-MBC50 and MIC-MBC90 respectively) have been calculated. Finally the percentage of resistant strains and the percentage of tolerant strains (ratio MBC/MIC: greater than or equal to 32) at low and high inoculum was determined. Erythromycin and aminoglycosides resulted the most active antibiotics against Campylobacter, being bactericidal as well as bacteriostatic at both low and high inoculum. Among the beta-lactams, cefotaxime was the most active, followed by piperacillin and ampicillin. Ceftazidime, aztreonam and rifampin were inactive. Ciprofloxacin, cotrimoxazole and tetracyclines showed some activity against Campylobacter at low inoculum. The agar disk diffusion method cannot be used for the "routinary" assay of susceptibility of Campylobacter, because it is a "naggy" microaerophilic organism.

Anti-Bacterial Agents↗

[Cephalosporins].

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Cephalosporins↗

Norfloxacin versus pipemidic acid in complicated urinary tract infections due to susceptible pathogens: a comparative clinical trial.

Norfloxacin (NOR) was compared to pipemidic acid (PA) in complicated urinary tract infections (UTIs) caused by pathogens susceptible to both agents to evaluate the antibacterial activity of the new 4-quinolone derivative. Sixty-five patients were randomly allocated to receive NOR or PA, 400 mg bid for 7 days, and the results evaluated for treatment efficacy at 5 weeks after completion of therapy. Overall microbiological cure was significantly greater in NOR-treated patients, as 19 of 26 were cured (73%), compared to only 16 of 39 (41%) in the PA group (p less than 0.05). Failures and relapses, considered together, were significantly (p less than 0.05) less frequent in patients treated with NOR (4/26) than in those receiving PA (18/39). Clinical response was strictly related to microbiological outcome: NOR had a broader antibacterial spectrum than PA and in this study seemed to be more efficacious in the treatment of complicated UTIs caused only by bacteria susceptible to both agents. This may be related to greater antibacterial activity and/or tissue penetration by NOR, which is thus to be preferred, according to the results of our study, in the treatment of complicated UTIs.

Clinical Trials as Topic↗

Cross-resistance between methicillin and cephalosporins for staphylococci: a general assumption not true for cefamandole.

The antibacterial activity of cefamandole was evaluated against 120 methicillin-susceptible and methicillin-resistant Staphylococcus aureus and coagulase-negative staphylococcal strains, using both large (10(8) CFU per ml) and small (10(4) CFU per ml) inocula. Cefamandole appeared superior to cephalothin against methicillin-resistant strains, displaying at 10 micrograms/ml a bacteriostatic and for some strains a bactericidal action against a large inoculum of bacteria.

Cefamandole↗

Characterization of hyperlipidemia in two patients with analbuminemia.

The results of plasma lipid and lipoprotein analysis in two related patients, brother (R.U.) and sister (R.R.) with analbuminemia, and three first-degree relatives (parents and sister) are reported. Both patients showed a remarkable increase in cholesterol and phospholipid levels, and there was a corresponding increase in serum apo B and apo A-I. This hyperlipidemia is due to a selective increase in LDL and HDL concentrations. R.U. showed an increase in both HDL2- and HDL3-cholesterol, R.R. only in HDL3-cholesterol. VLDL concentration was reduced in R.U. and normal in R.R. The plasma lipoprotein electrophoretic pattern did not correspond to any of the phenotypes in Fredrickson's classification. Composition of the different lipoprotein fractions was normal in the patients and family members. Serum FFA level in R.R. was very low. An increase in the plasma protein fractions, particularly the transport fractions, was confirmed in both patients. The possible pathophysiology of the hypercholesterolemia in these patients is discussed. Unlike other reported cases, clinical signs of atherosclerotic complications were absent.

Adult↗