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A C Pignatari

Publications and source records attributed to A C Pignatari.

At least 19 recordsLinked to original sources

Bloodstream infections in late-stage acquired immunodeficiency syndrome patients evaluated by a lysis centrifugation system.

Opportunistic infections, which affect acquired immunodeficiency syndrome (Aids) patients, are frequently disseminated and may cause bloodstream infections (BSI). The aim of this study was to evaluate the main causes of BSI in Aids patients with advanced stage of the disease, with special emphasis on the identification of fungemia. During a 21 months period, all patients with Aids (CD4 < 200) and febrile syndrome admitted to 3 university hospitals were systematically evaluated. For each patient presenting fever, a pair of blood cultures was collected and processed by using a commercial lysis-centrifugation system. One hundred and eleven patients (75 males) with a mean age of 36 years (median 33 years) and mean CD4 count of 64 cells/ml were included. Among the 111 patients evaluated we documented 54 episodes of BSI, including 46 patients with truly systemic infections and 8 episodes considered as contaminants. BSI were caused by gram-positive bacteria (43%), fungi (20%), gram-negative bacteria (15%), mycobacteria (15%), and mixed flora (7%). The crude mortality rate of our patients was 39%, being 50% for patients with BSI and 31% for the others. In conclusion, BSI are a common related to systemic infections on Aids patients with advanced stage of disease and is associated with a high rate of mortality.

AIDS-Related Opportunistic Infections↗

Typing of Enterococcus faecium by polymerase chain reaction and pulsed field gel electrophoresis.

Polymerase chain reaction (PCR) with JB1 or REP consensus oligonucleotides and pulsed field gel electrophoresis (PFGE) were used to study genomic DNA extracted from 31 strains of enterococci. Eleven ATCC strains, representative of 11 species of Enterococcus, were initially tested by JB1-PCR, revealing that Enterococcus malodoratus and Enterococcus hirae presented identical banding patterns. Eight Enterococcus faecium isolates from Stanford University and 12 from São Paulo Hospital were studied by JB1-PCR, REP-PCR (1/2)R and PFGE. Among the isolates from Stanford University, 5 genotypes were defined by JB1-PCR, 7 by REP-PCR (1/2)R and 4 by PFGE. Among the isolates from São Paulo Hospital, 9 genotypes were identified by JB1-PCR, 6 by REP-PCR and 5 by PFGE. The three methods identified identical genotypes, but there was not complete agreement among them.

Bacterial Typing Techniques↗

Comparative study of agar diffusion test and the NCCLS macrobroth method for in vitro susceptibility testing of Candida spp.

We performed a prospective double-blind study to evaluate the correlation between inhibition zones obtained by a disk-diffusion test, using Neo-sensitabs of fluconazole (Rosco Diagnostica), and the MICs generated by the NCCLS macrobroth dilution assay. Eighty clinical isolates, representing 5 of the clinically relevant species of Candida, were tested simultaneously by both methods. A clear inverse correlation was found between the results obtained by both tests (r = -0.69). In addition, there was high degree of agreement between methods in the identification of susceptible isolates. However, the resistance definition by disk-diffusion test had a positive predictive value of only 17%. Our data support the hypothesis that Rosco Fluconazole Neo-sensitabs have potential as a screening test for the identification of Candida isolates susceptible to fluconazole. Resistant isolates should be further investigated by standardized broth procedures.

Antifungal Agents↗

Geographic distribution of penicillin resistance of Streptococcus pneumoniae in Brazil: genetic relatedness.

From January 1993 through December 1996, 1,252 Streptococcus pneumoniae strains from different geographic regions of Brazil were studied for penicillin (Pen) susceptibility. All pneumococci were isolated from normally sterile fluids from patients, newborns to 88 years old. Pen resistance (R) had a mean rate of 15.1%, with 14.5% of strains showing intermediate level Pen-R and 0.6% showing high-level Pen-R. Similar Pen-R rates were observed in different regions of the country, in the range of 9.5% to 17.1%. A Pen-R increase was noted from 9.6% in 1993 to 20.6% in 1996. Pen-R was mostly associated to serotypes 6B, 14, 19A, and 23F (89%). Chromosomal DNA relatedness of Pen-R strains was determined by pulsed field gel electrophoresis (PFGE). High genetic diversity was identified, being represented by 27 patterns among the 92 strains. Two important features were observed: the predominance of relatively low-level Pen MIC (range 0.1-0.5 mg/L) in 86 of the 92 strains, and the presence of 60.8% as four major PFGE clusters unique to Brazil. Another feature was the geographic spread of these clusters over large distances in the country. The city of São Paulo seems to be a Pen-R focus (18.4%) in Brazil. Only two strains representing the international clone B widely spread in France, Portugal, and Spain, belonging to serotype 14, were found.

Brazil↗

Staphylococcus aureus prophylaxis in hemodialysis patients using central venous catheter: effect of mupirocin ointment.

Central venous catheterization is a common technique to establish rapid and temporary access for hemodialysis. However, it is a known risk factor for Staphylococcus aureus infection and bacteremia. Mupirocin is a topical antibiotic with high in vitro anti-staphylococcal activity. A randomized prospective trial was conducted to assess the effectiveness of mupirocin ointment in the prevention of Staphylococcus aureus skin and catheter colonization, and episodes of bacteremia in 136 end-stage renal disease patients. Of these, 67 received skin disinfection at the venous catheter insertion site with povidone iodine (control group), and 69 received the same treatment followed by application of 2% mupirocin ointment at the cannula site after catheter placement and at the end of each dialysis session. Patients were followed until catheter removal and were monitored for the development of Staphylococcus aureus skin/catheter colonization and episodes of bacteremia. Median duration of catheter use was greater in the mupirocin than in the control group (37 versus 20 d, P < 0.01). Patients in the mupirocin group had a significantly lower rate of Staphylococcus aureus isolation from the pericatheter skin (1.76 per 1000 versus 14.27 per 1000 patient-days, P < 0.001) and from the catheter surface (3.17 per 1000 versus 14.27 per 1000 patient-days, P < 0.001). The proportion of patients with Staphylococcus aureus skin infection at the insertion site was lower in the mupirocin group (4.3% versus 23.9%, P = 0.001). Staphylococcus aureus-associated bacteremia was observed in 17 patients (two in the mupirocin group [0.71 episodes per 1000 patient-days] and 15 in the control group [8.92 per 1000 patient-days], P < 0.001). The hazard ratio of developing Staphylococcus aureus bacteremia was 7.2 (95% confidence interval, 1.6 to 31.6) times greater in patients not receiving mupirocin. Mupirocin applied to the insertion site significantly reduces the risk of Staphylococcus aureus skin and catheter colonization, exit-site infection, and Staphylococcus aureus bacteremia in hemodialysis patients.

Adolescent↗

Use of macrorestriction analysis to demonstrate interhospital spread of multiresistant Acinetobacter baumannii in São Paulo, Brazil.

We evaluated the spread of Acinetobacter baumannii strains among three hospitals located in São Paulo, Brazil. A total of 46 isolates, which were typed by chromosomal DNA analysis with use of pulsed field gel electrophoresis (PFGE), were tested for susceptibility to the fluoroquinolones, carbapenems, aminoglycosides (amikacin), cephalosporins, polymyxin B, and ampicillin/sulbactam by means of the broth microdilution method, disk diffusion, and the E-test. Isolates with an identical PFGE pattern (pattern B) that were susceptible only to carbapenems, polymyxin B, and ampicillin/ sulbactam were recovered in all three hospitals. In addition, isolates with PFGE pattern A that were susceptible only to polymyxin B and ampicillin/sulbactam were recovered in hospitals 1 and 2. The results of our study strongly suggest the interhospital transmission of multiresistant epidemic strains of A. baumannii in São Paulo. Once in the hospital, these strains can disseminate and cause outbreaks with devastating consequences.

Acinetobacter↗

Antimicrobial activity of FK-037, a new broad-spectrum cephalosporin. International in vitro comparison with cefepime and ceftazidime.

The in vitro activity of FK-037, a new parenteral 7-aminothiazolyl-methoxyimino cephalosporin, was compared with cefepime and ceftazidime against 6094 aerobic isolates collected in six medical centers worldwide. FK-037 demonstrated potent activity against the Enterobacteriaceae family except for some Enterobacter spp., Providencia spp., and Serratia liquefaciens (MIC90s, > or = 16 micrograms/ml). Against nonenteric Gram-negative bacilli, all compounds tested showed similar, but more limited activity. The FK-037 MIC50s for Pseudomonas spp. and P. aeruginosa were 2 and 4 micrograms/ml, respectively. The least susceptible organisms were Xanthomonas maltophilia, enterococci, and Bacillus spp. (MIC50s, > 16 micrograms/ml), followed by Flavobacterium spp., other nonenterics, and oxacillin-resistant Staphylococcus aureus (MIC50s, 16 micrograms/ml). Good FK-037 activity was observed against oxacillin-susceptible staphylococci as well as against beta-hemolytic and viridans-group streptococci (MIC90 range, < or = 0.12 to 2 micrograms/ml). While FK-037 was slightly more active than cefepime against Gram-positive organisms, enteric bacilli were most susceptible to cefepime. Overall, the antibacterial spectrum of both FK-037 and cefepime was superior to ceftazidime.

Cefepime↗

Levofloxacin in vitro activity: results from an international comparative study with ofloxacin and ciprofloxacin.

Levofloxacin, the S-(-)-isomer of ofloxacin, was compared to ofloxacin and ciprofloxacin against > 6000 recent clinical isolates of Gram-positive and Gram-negative bacteria from six different countries. This international multicenter study demonstrated a high level of antibacterial activity of levofloxacin against all the members of Enterobacteriaceae [minimum inhibitory concentration (MIC)50s, < or = 0.03 to 0.12 mg/L] except Providencia rettgeri (MIC50, 2 mg/L), and Providencia stuartii (MIC50, 1 mg/L). Oxacillin-susceptible staphylococci (MIC50s, 0.12 to 0.25 mg/L), enterococci (MIC50s, 0.5 to 2 mg/L), and streptococci (MIC50s, 0.5 mg/L) were also susceptible to levofloxacin, but most isolates of oxacillin-resistant staphylococci had MICs of > or = 4 mg/L. Levofloxacin was also active against non-enteric Gram-negative bacilli, including Acinetobacter species (MIC50s, < or = 0.03 to 1 mg/L), Pseudomonas species (MIC50s, 0.5 to 1 mg/L) and Xanthomonas maltophilia (MIC50, 0.5 mg/L). Overall, levofloxacin inhibited 50% and 90% of all the tested strains at the concentrations of 0.12 and 4 mg/L, respectively. The activity of levofloxacin was generally two-fold greater than ofloxacin and equal to or slightly less potent than ciprofloxacin.

Asia↗

Evaluation of interhospital spread of methicillin-resistant Staphylococcus aureus in Sao Paulo, Brazil, using pulsed-field gel electrophoresis of chromosomal DNA.

To evaluate the interhospital spread of methicillin-resistant Staphylococcus aureus (MRSA) clone in Sao Paulo, we analyzed the restriction fragment length polymorphisms (RFLP) of chromosomal DNA from isolates from nine Sao Paulo hospitals. Restriction digestion of genomic DNA was performed with SmaI and the fragments were separated by pulsed-field gel electrophoresis. Only six different RFLP patterns were demonstrated among 30 MRSA isolates. Isolates possessing an identical RFLP pattern were demonstrated in eight of the nine Sao Paulo hospitals evaluated. Our results documented the widespread dissemination of a single clone of MRSA in several hospitals. Furthermore, the small clonal variability among multidrug-resistant MRSA coupled with the wide spread of this clone could make the intrahospital epidemiological evaluation of RMSA outbreaks very difficult.

Brazil↗

Epidemiologic typing of multiply drug-resistant Pseudomonas aeruginosa isolated from an outbreak in an intensive care unit.

From June to August 1991, there was an outbreak of Pseudomonas aeruginosa infections in an intensive care unit in a general hospital in Sao Paulo, Brazil. We obtained 14 isolates from 14 patients, 11 from tracheal aspirate, and 3 from surgical wound exudates. These strains were typed by serotyping, pyocin typing, and pulsed-field electrophoresis (CHEF) of chromosomal DNA (chrDNA), and the different typing methods were analyzed. These three methods demonstrated seven identical strains. We also performed an extensive antibiogram (33 drugs) in all 14 isolates. The incidence of resistance to aminoglycosides, extended-spectrum beta-lactams, and quinolones was very high among the seven identical isolates; however, the antibiogram profile differed significantly among the isolates. Our results suggest that a unique strain caused several cross-transmitted infections during this period of time, and the emergence of antimicrobial resistance has been occurring before and after the establishment of the epidemic strain by selective drug use. The chrDNA fingerprinting proved to be versatile and precise for epidemiologic investigations of P. aeruginosa infections.

Brazil↗

Oxacillin- and quinolone-resistant Staphylococcus aureus in Sao Paulo, Brazil: a multicenter molecular epidemiology study.

OBJECTIVE: To investigate the possibility of interhospital spread of multiresistant Staphylococcus aureus in Sao Paulo, Brazil. DESIGN: We evaluated 13 nosocomial S aureus strains selected because of resistance to oxacillin and ciprofloxacin. SETTING: The strains were collected between March 1991 and September 1991 from four different hospitals in Sao Paulo. Two were teaching hospitals, and two were private hospitals. PATIENTS: Each strain was isolated from a different patient. All patients were hospitalized when the strains were isolated. INTERVENTIONS: The strains were typed by restriction endonuclease analyses of plasmid DNA (REAP) using EcoRI, HindIII, RsaI, and AluI and by extended antibiogram profile (34 drugs). RESULTS: All strains had identical plasmid and antibiogram profile. They demonstrated the same plasmid pattern as previously described in one of the hospitals studied. CONCLUSIONS: Our results suggest the dissemination of a unique oxacillin- and quinolone-resistant strain of S aureus in several hospitals of Sao Paulo, Brazil.

Bacterial Typing Techniques↗

Restriction endonuclease analysis of Staphylococcus aureus plasmid DNA from three continents.

Staphylococcus aureus isolates (n = 1201) from 20 centers in Europe, the USA and Brazil were evaluated for the presence of epidemiologic markers. Plasmid typing and restriction endonuclease analysis of plasmid DNA confirmed the presence of an apparently identical plasmid in 13% of clinical isolates. The plasmid was recovered from all 20 hospitals studied, with an overall frequency of greater than 10% on each of the three continents. Since relatively few staphylococcal plasmids may be shared by epidemiologically unrelated strains, there are inherent limitations to this otherwise useful technique. Additionally, these data demonstrate the importance of including unrelated strains of Staphylococcus aureus from the local region as controls when molecular typing methods are performed.

Brazil↗

In vitro activity of three carbapenem antibiotics. Comparative studies with biapenem (L-627), imipenem, and meropenem against aerobic pathogens isolated worldwide.

The in vitro activity of biapenem (formerly L-627 or LJC10, 627), a new carbapenem, was compared with that of imipenem and meropenem against > 6000 clinically significant pathogens isolated in six countries worldwide. Biapenem was active against members of the family Enterobacteriaceae with a 90% minimum inhibitory concentration (MIC90) ranging from < or = 0.06 to 2 micrograms/ml. Only Serratia spp. and Providencia spp. were less susceptible (MIC90, 8 micrograms/ml). Pseudomonas aeruginosa and Xanthomonas maltophilia displayed an MIC90 of > or = 8 micrograms/ml biapenem/ml whereas Acinetobacter spp. were susceptible at < or = 1 micrograms/ml. Oxacillin-resistant staphylococci were resistant to biapenem at > 8 micrograms/ml whereas oxacillin-sensitive staphylococci were susceptible at < or = 1 micrograms/ml. Biapenem, imipenem, and meropenem displayed poor activity against Ent. faecium (MIC90, > or = 8 micrograms/ml), and only imipenem displayed slightly better activity against Ent. faecalis (MIC90, 4 micrograms/ml). The rank order of activity against groups of isolates was Enterobacteriaceae (meropenem > biapenem > or = imipenem), Ps. aeruginosa (biapenem = meropenem = imipenem), oxacillin-sensitive staphylococci (imipenem > or = biapenem = meropenem), oxacillin-resistant staphylococci (biapenem = meropenem = imipenem), and Enterococcus spp. (biapenem = meropenem = imipenem). These in vitro suggest that further developmental work on biapenem is warranted.

Enterobacteriaceae↗