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Mario Venditti

Publications and source records attributed to Mario Venditti.

18 recordsLinked to original sources
PubMed2006

Staphylococcus haemolyticus endocarditis: clinical and microbiologic analysis of 4 cases.

Only 3 cases of infective endocarditis (IE) due to methicillin-resistant Staphylococcus haemolyticus (MRSH) have been reported in English literature. Here we report 4 cases of IE due to MRSH encountered in a single university hospital. Population analysis of the strains was performed to assess the presence of vancomycin/teicoplanin heteroresistant subpopulations. Pulsed-field gel electrophoresis was used for molecular typing of isolates. IE was defined in 3 cases as health care associated, and in 1 case, as community acquired. A causative strain was lost. Two strains were heteroresistant to teicoplanin, and 1 also to vancomycin. Genome macrorestriction profile studies demonstrated that 2 MRSH isolates belonged to clones A and E, possessing a class C1 mecDNA, whereas 1 clone was sporadic. All patients were treated with vancomycin plus rifampin. Two patients were cured with antibiotic therapy alone, 1 patient needed surgery, and 1 patient died. Methicillin-resistant multiresistant S. haemolyticus may represent a difficult-to-treat cause of both community and nosocomially acquired IE.

Aged↗
PubMed2006

A plasma expander-related Pseudomonas aeruginosa outbreak.

Nine patients developed P. aeruginosa bloodstream infection (BSI) in a neurosurgical intensive care unit (NSICU) during a 2-month period. Environmental strains were isolated from a plasma-expander solution and tap water. All clinical and plasma-expander strains displayed the same PFGE pattern, whereas the water strains were unrelated to the outbreak.

Bacteremia↗
PubMed2006

Relationship between biofilm formation, the enterococcal surface protein (Esp) and gelatinase in clinical isolates of Enterococcus faecalis and Enterococcus faecium.

One-hundred and twenty-eight enterococcal isolates were examined for their ability to form biofilm in relation to the presence of the gene encoding the enterococcal surface protein (esp), production of gelatinase and to the source of isolation. Neither esp nor gelatinase seemed to be required for biofilm formation: both Enterococcus faecalis and Enterococcus faecium did not show a correlation between the presence of either esp or the production of gelatinase and biofilm formation. However, in E. faecium while esp was found in isolates from either source, the presence of both esp and biofilm together was only found in strains from clinical settings, suggesting that there exists a synergy between these factors which serves as an advantage for the process of infection.

Bacterial Proteins↗
PubMed2005

Surveillance and infection control in an intensive care unit.

OBJECTIVE: To evaluate the effect of an infection control program on the incidence of hospital-acquired infection (HAI) and associated mortality. DESIGN: Prospective study. SETTING: A 2000-bed, university-affiliated hospital in Italy. PATIENTS: All patients admitted to the general intensive care unit (ICU) for more than 48 hours between January 2000 and December 2001. METHODS: The infection control team (ICT) collected data on the following from all patients: demographics, origin, diagnosis, severity score, underlying diseases, invasive procedures, HAI, isolated microorganisms, and antibiotic susceptibility. INTERVENTIONS: Regular ICT surveillance meetings were held with ICU personnel. Criteria for invasive procedures, particularly central venous catheters (CVCs), were modified. ICU care was restricted to a team of specialist physicians and nurses and ICU antimicrobial therapy policies were modified. RESULTS: Five hundred thirty-seven patients were included in the study (279 during 2000 and 258 in 2001). Between 2000 and 2001, CVC exposure (82.8% vs 71.3%; P < .05) and mechanical ventilation duration (11.2 vs 9.6 days) decreased. The HAI rate decreased from 28.7% in 2000 to 21.3% in 2001 (P < .05). The crude mortality rate decreased from 41.2% in 2000 to 32.9% in 2001 (P < .05). The most commonly isolated microorganisms were nonfermentative gram-negative organisms and staphylococci (particularly MRSA). Mortality was associated with infection (relative risk, 2.11; 95% confidence interval, 1.72-2.59; P < .05). CONCLUSION: Routine surveillance for HAI, coupled with new measures to prevent infections and a revised policy for antimicrobial therapy, was associated with a reduction in ICU HAls and mortality.

Adult↗
PubMed2005

Invasive infections caused by Trichosporon species and Geotrichum capitatum in patients with hematological malignancies: a retrospective multicenter study from Italy and review of the literature.

Trichosporonosis is an uncommon but frequently fatal mycosis in immunocompromised patients. A multicenter retrospective study was conducted to characterize cases of proven or probable invasive trichosporonosis diagnosed over the past 20 years in Italian patients with hematological diseases. Of the 52 cases identified, 17 were classified as Trichosporon sp. infections and 35 were attributed to Geotrichum capitatum. Acute myeloid leukemia accounted for 65.4% of the cases. The incidence rates of Trichosporon sp. and G. capitatum infections in acute leukemia patients were 0.4 and 0.5%, respectively. Overall, 76.9% of cases had positive blood cultures. Pulmonary involvement was documented in 26.9% of cases. Death was reported for 57.1% of G. capitatum infections and for 64.7% of Trichosporon sp. infections. A literature review on trichosporonosis in patients with any underlying disease or condition reveals G. capitatum as a predominantly European pathogen, particularly in certain Mediterranean areas, while Trichosporon sp. infections are seen with similar frequencies on all continents. The majority of published Trichosporon sp. and G. capitatum infections occurred in patients with hematological diseases (62.8 and 91.7%, respectively). Well over half of these were suffering from acute leukemia (68 and 84% of patients with Trichosporon sp. and G. capitatum infections, respectively). Crude mortality rates were 77% for Trichosporon spp. and 55.7% for G. capitatum. The optimal therapy for trichosporonosis has yet to be identified; however, in vitro experiences are providing encouraging evidence of the potential role of the new triazoles, in particular, voriconazole.

Adolescent↗
PubMed2005

In vitro activity of fosfomycin in combination with vancomycin or teicoplanin against Staphylococcus aureus isolated from device-associated infections unresponsive to glycopeptide therapy.

Fosfomycin is a molecule that inhibits the early stage of peptidoglycan synthesis and shows a broad-spectrum bactericidal activity against Gram-positive and Gram-negative bacteria. Using the Killing-curve method, we tested the in vitro bactericidal activity of fosfomycin alone or in combination with vancomycin or teicoplanin at a concentration of 8 microg/mL, that is easily achievable in serum at standard dosing regimens, against seven methicillin-resistant Staphylococcus aureus strains, isolated from patients with well documented device-associated infections unresponsive to or relapsing after glycopeptide therapy. MICs of vancomycin ranged from 1 to 4 microg/mL, MICs of teicoplanin from 2 to 8 microg/mL; MICs of fosfomycin were 8 microg/mL for two strains and >128 microg/mL for the remaining strains. The seven strains proved tolerant when tested for vancomycin and teicoplanin used alone at 2x MIC concentration. Fosfomycin was bactericidal (reduction of 2 log of the inoculum) only against the two susceptible strains. In all cases both vancomycin and teicoplanin in combination with fosfomycin developed bactericidal synergism already at a concentration of 1x MIC. If these results are confirmed by in vivo experiments, the combination of fosfomycin with glycopeptides might be useful for treating device-associated infections, and in preventing the phenomenon of increasing MICs for glycopeptides.

Anti-Bacterial Agents↗
PubMed2004

Identification of a variant "Rome clone" of methicillin-resistant Staphylococcus aureus with decreased susceptibility to vancomycin, responsible for an outbreak in an intensive care unit.

We describe the identification of a variant of the "Rome clone" of methicillin-resistant Staphylococcus aureus (MRSA), responsible for an outbreak involving 5 patients in a Cardiac Surgery Intensive Care Unit (CS-ICU) of a tertiary-care University Hospital in Rome. All strains isolated from patients and from nasal swabs obtained from four members of the CS-ICU personnel, belonged to the same identified clone. The characteristics of this clone were: (1) resistance to ampicillin, oxacillin, gentamicin, ciprofloxacin, erythromycin, clindamycin, rifampin, spectinomycin, and tetracycline; (2) vancomycin and teicoplanin MICs respectively of 2 and 4 mg/L; (3) heteroresistant subpopulations in the presence of 4 and 6 mg/L of vancomycin (10(-3) and 10(-5), respectively); (4) clonal type I::J::C determined following an established protocol (mec A::Tn 554 ::PFGE); (5) sequence type ST247 (3-3-1-12-4-4-16), obtained by multilocus sequence typing (MLST); and (6) the staphylococcal cassette chromosome mec (SCC) IA, obtained by multiplex PCR method. This new strain had different characteristics from the epidemic clone circulating in the same hospital from 1997 and designed "Rome clone," which was susceptible to erythromycin, clindamycin, and spectinomycin and belonged to the II::NH::C genetic background. A high genetic similarity between this Rome clone and the previously classified Archaic and Iberian clones was found, because they shared the same allelic profile (ST247), probably originating from the same S. aureus ancestor of the Iberian MRSA strains. Therefore, the strains responsible for the outbreak, with vancomycin MICs 2-4 mg/L, are variant clones, showing the genotype of the "Rome clone," the ST247 in association with SCC mec type IA (ST247-MRSA-IA), and are characterized by a uniform susceptibility to fosfomycin.

Anti-Bacterial Agents↗
PubMed2003

Fluconazole in combination with flucytosine in the treatment of fluconazole-resistant Candida infections.

Two patients with renal failure and fluconazole resistant but flucytosine susceptible Candida deep infection were successfully treated with the combination of the two drugs. In vitro susceptibility, determined by microdilution and time-kill methods, and fungostatic activity of the serum showed an additive interaction of fluconazole and flucytosine. In the event of infections by Candida isolates resistant to fluconazole but susceptible to 5-fluorocytosine, the combination of these drugs may be a possible therapeutic choice.

Antifungal Agents↗
PubMed2003

Tc-99m exametazime-labeled leukocyte scans in the study of infections in skull neurosurgery.

Diagnosis and follow-up of skull infections are usually performed by neurologic examination, laboratory tests and instrumental diagnostic methods such as computed tomography (CT) and magnetic resonance imaging (MRI). These have, however, shown some limitations for specificity. The aim of the current study was to evaluate the overall contribution of Tc-99m exametazime-labeled leukocyte imaging scan Tc-99m hexamethylpropyleneamine (HMPAO) labeled white blood cells (WBC) in the diagnosis and management of infections in skull neurosurgery. Thirty-four patients were subdivided into 4 groups on the basis of the suspected pathology: intracerebral lesions on CT or MRI (group A, n = 20), suspected postsurgical infections (group B, n = 6), suspected deep infection of the surgical wound (group C, n = 4), and suspected infection of the ventriculoperitoneal shunt (group D, n = 4). All patients underwent CT, MRI, and Tc-99m HMPAO WBC imaging. Patients in group C also underwent bacteriologic and culture examinations of wound secretions if present. In positive cases in group A, Tc-99m HMPAO WBC imaging was repeated. The scintigraphic results were compared with histologic findings in patients who underwent surgery and with the results of a 12-month clinical follow-up in the remaining patients. Tc-99m HMPAO WBC scans correctly detected the infections in all groups. Furthermore, such imaging proved to be able to document recovery from the disease in all of the assessed cerebral abscesses. This study may have an important role both in the diagnosis and in the management of infections in skull neurosurgery, which, it is hoped, will be confirmed in the future.

Adult↗
PubMed2003

Outbreak of Saccharomyces cerevisiae subtype boulardii fungemia in patients neighboring those treated with a probiotic preparation of the organism.

We report an outbreak of Saccharomyces cerevisiae subtype boulardii fungemia among three intensive care unit roommates of patients receiving lyophilized preparations of this fungus. The fungemia was probably due to central venous catheter contamination and resolved after fluconazole treatment. The need for stringent application of proper hygiene when using a probiotic preparation of this organism is emphasized.

Adult↗
PubMed2003

Staphylococcus aureus bacteremia in patients with hematologic malignancies: a retrospective case-control study.

BACKGROUND AND OBJECTIVES: Staphylococcus aureus bacteremia (SAB) continues to be a major problem related to both community and nosocomially acquired infection. Nevertheless few data are presently available in literature about this infection in patients with hematologic malignancies. DESIGN AND METHODS: The purpose of this retrospective study was to report further data on the clinical characteristics and outcome of patients with SAB. All episodes of SAB occurring between January 1997 and June 2001 were identified and defined by analysis of the patients' clinical records. RESULTS: The nosocomial mortality rate was only 3.5% and no patient developed secondary complications. Comparison between neutropenic hematologic patients with SAB and neutropenic hematologic patients with Gram-negative bacteremia (GNB) revealed an higher mortality in the latter group (p=0.03); furthermore, severe sepsis and septic shock were more frequent in patients with GNB (p<0.001). Comparison between neutropenic patients with hematologic malignancies and non-neutropenic ones with other underlying diseases revealed significantly higher morbidity and mortality rates in the latter group. Non neutropenic patients seemed to be more susceptible to both early complications, such as severe sepsis or septic shock (p=0.002) and to later ones, such as endocarditis and metastatic abscesses (p=0.02). INTERPRETATION AND CONCLUSIONS: Our results seem to suggest that SAB in patients with hematologic malignancies is often a low inoculum infection associated with negligible morbidity and mortality rates, especially when adequate antistaphylococcal therapy is administered promptly.

Adolescent↗
PubMed2003

[Non-tubercular and non-brucellar spondylodiscitis: preliminary clinico-microbiologic analysis of 37 cases].

Disk-space infection caused by organisms other than Mycobacterium tuberculosis or Brucella species seems to be an emerging disease due to an increase of the population at risk. However, few data are presently available from Italian institutions. In this article we report our "tot" month prospective experience on etiology and clinical presentation of disk-space infections in relation to their community (COM) or nosocomial (postoperative [POS] or non-postoperative [NPOS]) acquisition. Major results were: 1) a different microbial distribution among etiologies of COM, NPOS and POS infections; 2) more frequent distance infection as predisponing factor among NPOS infection than among COM and NPOS ones; 3) absence of fever and more frequent radicular extension of pain among POS infections. Due to the numerous potential microbial etiologies, culture of TC guided-disk aspirated material is of paramount importance for pathogen-targeted antimicrobial therapy.

Discitis↗
PubMed2002

[Piperacillin-tazobactam in the treatment of severe nosocomial infections].

Epidemiology and clinical manifestations of nosocomial infections have been progressively evolving through last three decades. New pathogens, often associated to multiple antibiotic-resistances, are now among the leading etiologies in a patient population mainly represented by individuals debilitated by serious underlying diseases, immunosuppressive treatments and multiple diagnostic and therapeutic invasive procedures. Under these circumstances, when an infectious complication develops, prompt initiation of empiric antibiotic therapy, based on general and/or local epidemiology of nosocomial infections, may be crucial for survival of more critically ill patients. Based on recent data, the antibiotics of choice for treatment of nosocomial infections should have not only a bactericidal activity and a broad antibacterial spectrum, but also poor propensity to induce antibiotic-resistance and a satisfactory pharmacoeconomy profile. After a detailed description of the above mentioned context, the pre-eminent role of piperacillin-tazobactam in the treatment of nosocomial infections is reviewed and discussed.

Bacteria↗
PubMed2002

[Microbiological surveillance in an intensive care unit of a large Roman hospital].

Infection surveillance in ICU is fundamental to monitor endemic rates, to identify outbreaks on-time in order to activate control procedures implementing a correct empirical antibiotic treatment. The data collection surveillance software CIN-20002 was established in the Teaching Hospital Umberto I ICU to monitor the following site-specific infection rates: urinary tract infections (UTI), pneumonia (PNE), blood stream infections (BSI), surgical site infections (SSI). According to CDC definitions all patients developing infection 48 hours or more after ward admission were included. Furthermore risk factors (i.e. age, sex, SAPS II), invasive procedures (i.e. endotracheal intubation, vascular and urinary catheterisation), microbiological isolates and their antibiotic susceptibility were screened. Overall 279 patients (183 men and 96 women) were admitted; age 54,8 20,3 years (mean), SAPS II 44,4 17,1 (mean) and average ward stay 13,3 17,8 days. Results showed a total of 121 infection episodes (56 PNE, 51 BSI, 10 UTI e 4 SSI) in 80 patients (28,7%). Standardized infection rates associated to invasive procedures were: Urinary catheter-associated UTI rate (2.9/1000), Ventilator-associated PNE rate (20.4/1000), Vascular catheter-associated BSI rate (19.1/1000). Among the infected patients the most common microrganisms isolated were P. aeruginosa (31,8%), MRSA (14,8%), A. baumanni (12,5%) e S. maltophilia (8,5%). Considering site-specific infections: PNE (P. aeruginosa 38,3% and MRSA 18,1%), BSI (MR CNS 21,9% and P. aeruginosa 17,2%), UTI (P. aeruginosa 70,0%). The surveillance software CIN-2000 proved to be very accurate, usefull and easy to use. The results showed a high incidence of infections associated to invasive procedures and the presence of multiresistant bacteria

Cross Infection↗
PubMedDate not supplied

[Staphylococcus aureus sepsis in hospitalized non neutropenic patients: retrospective clinical and microbiological analysis].

Staphylococcus aureus is one of the leading agents of nosocomial infection among adult patients. The aim of this study was to determine the predisposing factors and secondary complications of Staphylococcus aureus septicemia (SAS) in non neutropenic patients, as well as the predictors of the outcome in non neutropenic patients with SAS. We performed a retrospective study of 56 cases of SAS that occurred from January 1997 through June 2001 in patients hospitalized in medical wards at the Policlinico Umberto I, "La Sapienza" University of Rome; we excluded surgical patients and those admitted to the intensive care unit. The median age was 61.9 years (range 24-89 years), 29 (51%) patients were male, and infection was hospital-acquired in 83.5% of cases. Metastatic infections were found in 12 patients (21.4%), with 6 (10.7%) developing infectious endocarditis; the relapse rate was 8.9%; 30.3% of Staphylococcus aureus isolates were methicillin-resistant. The overall mortality was 41% and the attributable mortality 28.5%. Twenty-nine patients who developed metastatic infections or died for sepsis were compared with 27 patients who did not develop complications. At univariate analysis, the following factors were associated with a complicated course: delay to adequate antibiotic therapy (2.46 vs 1.15 days, p < 0.03), persistent Staphylococcus aureus bacteremia during antibiotic therapy (3.56 vs 1.51 days, p = 0.01), septic shock (58.6 vs 3.7%, p < 0.002), bacteremic pneumonia as the source of bacteremia (17.2 vs 0%, p = 0.02), and the increased severity of illness at the onset of SAS as evaluated using an "illness score" (4.2 vs 2.1, p < 0.002). At multivariate analysis, septic shock (p < 0.01) and delay to adequate antibiotic therapy (p = 0.05) were confirmed as associated with a complicated outcome. SAS in non neutropenic patients is associated with significant morbidity consequent to a high rate of metastatic infectious disease and with a considerable related mortality.

Adult↗
PubMedDate not supplied

Soft tissue infection caused by Mycobacterium chelonae following a liposculpture and lipofilling procedure.

Skin and soft tissue infections that usually follow minor traumatic events or surgical procedures are caused by a wide spectrum of bacteria. We describe a soft tissue infection caused by a Mycobacterium chelonae in an immunocompetent patient who underwent liposculpture and lipofilling of the gluteal-trochanteric region, emphasizing the importance of clinical suspicion and effective treatment of infection.

Female↗