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F Ardito

Publications and source records attributed to F Ardito.

34 records · Page 2Linked to original sources
PubMed2000

Comparison of the mycobacteria growth indicator tube with radiometric and solid culture for isolation of mycobacteria from clinical specimens and susceptibility testing of Mycobacterium tuberculosis.

We compared the mycobacteria growth indicator tube (MGIT) system with the BACTEC 460 TB and Loewenstein-Jensen (LJ) systems for the recovery of mycobacteria (acid-fast bacilli [AFB]) from 600 clinical specimens. A total of 50 AFB (32 Mycobacterium tuberculosis complex, 10 M. avium complex, 3 M. gordonae, 3 M. xenopi, 1 M. terrae and 1 M. fortuitum) were detected. MGIT recovered 50 isolates of AFB (100% sensitivity), and BACTEC 460 TB and LJ recovered 49 (98% sensitivity) and 19 (38% sensitivity) AFB isolates, respectively. The mean times to detect mycobacteria were 10, 10 and 25 days for MGIT, BACTEC 460, and LJ slants. All isolates of M. tuberculosis complex were tested for susceptibility to streptomycin, isoniazid, rifampin, and ethambutol with the MGIT and BACTEC 460 TB. Both systems yielded identical susceptibility data with different mean times to report (5.38 days for MGIT versus 7.33 days for BACTEC 460 TB, P<0.05). The results suggest that MGIT is equivalent to BACTEC 460 TB in its ability to support the growth of mycobacteria, but significantly more efficient than LJ. MGIT may also be used for susceptibility testing of primary antituberculosis drugs.

Anti-Bacterial Agents↗
PubMed1999

Application of molecular methods for detection and transmission analysis of mycobacterium tuberculosis drug resistance in patients attending a reference hospital in Italy.

A molecular analysis of drug-resistant isolates of Mycobacterium tuberculosis was done in a population with a high prevalence of human immunodeficiency virus infection. Seventy-one consecutive isolates were tested for genotypic resistance to isoniazid, rifampicin, streptomycin, and ethambutol by polymerase chain reaction-single strand conformation polymorphism analysis and automated sequencing of target regions. Phenotypic and genotypic resistance to isoniazid, rifampicin, streptomycin, and ethambutol were detected in 23.4%, 11.2%, 7%, and 5.6% of isolates and in 87%, 88%, 40%, and 100% of resistant isolates, respectively. Specificity was 100% for all target regions. When rpoB, katG, and ahpC mutation analysis were combined, 86% of resistant isolates to any drug were identified. No mutations in inhA were found in isoniazid-resistant isolates. Molecular detection of drug resistance, particularly for isoniazid and rifampicin, may represent a sensitive and very specific technique. The strategy of selecting rpoB, katG, and ahpC to quickly identify most resistant isolates, with a relevant saving of resources, is warranted.

Drug Resistance, Microbial↗
PubMed1998

Bacterial pneumonia in HIV-infected patients: analysis of risk factors and prognostic indicators.

This case control study assessed risk factors and prognostic indicators of 350 episodes of bacterial pneumonia in 285 HIV-infected patients. On univariate analysis, intravenous drug abuse (i.v.DA; p < .001 versus controls), regular cigarette smoking (p < .001), cirrhosis (p = .04), and history of a previous episode of pneumonia (p = .04) were risk factors for community-acquired episodes of bacterial pneumonia, whereas length of hospitalization (p = .01) was a risk factor only for nosocomial bacterial pneumonia. The small amount of circulating T CD4+ cells (<100/ mm3) was a risk factor in both groups of pneumonia (p < .05). Stepwise logistic regression analysis revealed that i.v.DA in community-acquired episodes and low levels of circulating T CD4+ cells, both in community-acquired and hospital-acquired episodes, were independent risk factors for the development of bacterial pneumonia. The case-fatality rate observed in our study was 27%. On stepwise logistic regression analysis, T CD4+ cell counts < or = 100/mm3 (p = .02), neutropenia (p = .04), PO2 arterial level < or = 70 mm Hg (p = .01), and Karnofsky score < or = 50 (p = .04) were independent indicators of mortality. According to a personally developed prognostic score, 211 episodes of pneumonia (60%) were classified as mild, 63 (18%) as moderate, and 76 (22%) as severe. Clinicians must carefully evaluate those variables that can influence the prognosis of bacterial pneumonia to make early identification of affected patients and to promptly establish the most appropriate therapeutic strategy in each case.

AIDS-Related Opportunistic Infections↗
PubMed1998

Polymerase chain reaction-reverse cross-blot hybridization assay in the diagnosis of sporotrichoid Mycobacterium marinum infection.

In this paper, we report a patient in whom Mycobacterium marinum sporotrichoid infection was diagnosed using polymerase chain reaction (PCR) amplification of the 16S rRNA gene and subsequent analysis of the amplified product in a reverse cross-blot hybridization assay with mycobacterial species-specific probes. This molecular method allowed us rapidly to detect and identify this organism directly in the patient's lesional skin biopsy rather than in cultures in conventional media. The identification provided by PCR-reverse cross-blot hybridization assay was confirmed by examination of the morphological and biochemical features and by high-performance liquid chromatography analysis of mycolic acid from the clinical isolate, suggesting the validity of our molecular approach.

Adult↗
PubMed1998

Routine use of PCR-reverse cross-blot hybridization assay for rapid identification of Mycobacterium species growing in liquid media.

A PCR-reverse cross-blot hybridization assay procedure that is able to rapidly identify 13 species of clinically relevant mycobacteria was evaluated for routine use in the identification of acid-fast isolates growing in BACTEC 460 TB (12B and 13A) and BACTEC 9000 MB (Myco/F) liquid media. Eight of the probes used were already described by Kox et al. (L. F. F. Kox et al., J. Clin. Microbiol. 33:3225-3233, 1995). In addition, we used six other probes specific for M. chelonae, M. malmoense or M. szulgai, M. genavense, M. gordonae, M. terrae, and M. marinum/M. ulcerans that we designed ourselves. This procedure allowed us to identify 459 mycobacterial species directly from broth cultures of 5,466 clinical samples collected over 1 year and processed with the radiometric or nonradiometric BACTEC system. Our results were in agreement with those obtained by conventional identification methods and also with those obtained by mycolic acid analysis by high-performance liquid chromatography. This assay seems to be a reliable procedure for the routine identification of mycobacteria, providing an accurate identification of mycobacterial isolates more rapidly than conventional tests, with remarkable implications for an efficacious specific antimycobacterial therapy.

Chromatography, High Pressure Liquid↗
PubMed1998

Evaluation of the Abbott LCx Mycobacterium tuberculosis assay in comparison with culture methods in selected Italian patients.

A ligase chain reaction (LCR) DNA amplification method for the molecular diagnosis of Mycobacterium tuberculosis (Abbott LCx MTB) was evaluated in comparison with solid and liquid phase culture on 622 selected samples collected in two large Italian hospitals, of which 310 obtained from HIV-1 positive patients and 312 from HIV-negative individuals. The overall prevalence of mycobacteria by culture was 22% (137/622), and the apparent sensitivity and specificity of LCx vs. culture were 87.6% and 98.2%. Of the 26 culture positive/LCx negative samples, 22 were positive for MOTT and 4 for M. tuberculosis. All 9 samples positive by LCx and negative by culture were classified as true positive by clinical criteria. The final values of sensitivity, specificity, positive predictive value and negative predictive value for LCx rose to 96.8%, 100%, 100% and 99.2%, respectively. The adjusted sensitivity of culture methods was 89.5% for solid phase and 92.7% for Bactec. In view of the high sensitivity on both smear-positive (100%) and smear-negative (92.4%) samples and of the high negative predictive value, the LCR-based amplification method appears suitable as a routine screening method for the rapid diagnosis of M. tuberculosis in high-risk patients.

DNA, Bacterial↗
PubMed1997

Evaluation of a nonradiometric system (BACTEC 9000 MB) for detection of mycobacteria in human clinical samples.

This study was carried out to evaluate the rate of recovery and time required for detection of mycobacteria from pulmonary and extrapulmonary human clinical samples, by using a fluorescence-quenching-based oxygen sensor (BACTEC 9000 MB; Becton Dickinson Microbiology Systems, Sparks, Md.). The results were compared with those obtained by microscopy, conventional culture in Lowenstein-Jensen (LJ) medium, and a BACTEC radiometric system (BACTEC 460 TB; Becton Dickinson). Of the 779 clinical samples processed, 364 from pulmonary sites and 415 from extrapulmonary sites, 62 (7.9%) were positive for mycobacterial isolates; of the positive samples, 59 (95.1%) were detected with the fluorescent BACTEC 9000 MB system, 57 (91.9%) were detected with the radiometric system (BACTEC 460 TB), and 43 (69.3%) were detected with LJ conventional culture. The mean times to detection of all mycobacteria with BACTEC 9000 MB and BACTEC 460 TB were similar (10.3 and 10.0 days, respectively). The results obtained indicate that the nonradiometric BACTEC (BACTEC 9000 MB) system is as efficient as Bactec 460 TB and significantly more efficient than LJ for the rapid recovery of mycobacteria from both pulmonary and extrapulmonary clinical specimens. Though the BACTEC 9000 MB system is recommended for respiratory specimens, we demonstrated that it can be successfully used also for recovery of mycobacteria from clinical specimens from various extrapulmonary sites.

Bacteriological Techniques↗
PubMed1997

The role of bronchoalveolar lavage in the microbiological diagnosis of pneumonia in patients with haematological malignancies.

In the aetiological diagnosis of pulmonary infections in patients affected by haematological malignancies we evaluated the utility of bronchoalveolar lavage (BAL). One hundred and twenty-seven BAL were performed in 119 patients. In our series, we identified the agent of pneumonia in 53.5% of episodes with the best results in aspergillosis, very common in these patients. The previous empirical anti-infective treatment was modified in 14 episodes (11%). The procedure was generally well tolerated and only one patient bled. We maintain that BAL is a useful diagnostic tool for detecting the agents of pulmonary infections in patients with haematological malignancies, especially when the routine microbiological procedures fail, and it also represents a good alternative to more invasive procedures.

Adolescent↗
PubMed1985

A study on the incidence of nosocomial infections in a large university hospital.

The results of a study on the incidence of nosocomial infections in a 1800 bed University hospital are reported. The study, carried out over a 9 months period, included: continuous microbiological surveillance, and a clinical and epidemiological survey. On the basis of the microbiological data collected and analyzed by a computer data system, developed and employed for the control of nosocomial infections, a weekly bed-to-bed survey was carried out by the staff of the Institute of Infectious Diseases. Among 2777 suspected nosocomial infections, as revealed by microbiological monitoring, 701 were confirmed after the bed-to-bed survey. The nosocomial infection rate was 6.75 per 100 discharges. It was higher in the surgical than in the medical wards (7.3 and 6 per 100 discharges, respectively). Nosocomial urinary tract infections were the most frequent (74.2%). The urinary infection rate was higher in the surgical than in the medical wards (5.3 and 4.6 per 100 discharges, respectively). Escherichia coli (19.4%), Pseudomonas aeruginosa (19.3%), Proteus spp. (18.4%) were the pathogens most frequently associated with nosocomial infections. They were followed by Klebsiella pneumoniae (7.8%) and Staphylococcus aureus (6.5%) in frequency. Among the risk factors, involved in nosocomial infections, the importance of catheterization was confirmed: among our patients with nosocomial urinary tract infections, 73.4% and 79.5%--in the medical and surgical wards, respectively--underwent urological instrumentation, mainly catheterization. An analogous and more detailed study is now in progress and will be extended in the next years.

Aged↗
PubMedDate not supplied

No evidence of hematopoietic stem cell mobilization in patients submitted to hepatectomy or in patients with acute on chronic liver failure.

BACKGROUND: Liver regeneration is a heterogeneous phenomenon involving the proliferation of different cell lineages in response to injury. Under a strong positive selection pressure bone marrow derived stem cells may be involved in this process, by making a contribution to both parenchymal restoration and endothelial cell replacement. We investigate bone marrow stem cell migration to the liver in patients undergoing hepatectomy or with acute on chronic liver failure. METHODS: We enrolled 6 patients submitted to hepatectomy, 6 patients to cholecystectomy and 8 patients with acute decompensation of liver cirrhosis. Mobilization of CD34+ cells was evaluated by cytofluorimetry on peripheral blood samples at different time points; baseline, 1, 3, 7, 15 and 30 days after surgery and at admission, 1, 7 and discharge among patients with acute on chronic liver failure. 10 healthy subjects undergoing blood donation were also enrolled to evaluated the basal value of CD34+ cells. RESULTS: White blood cell counts remained in the normal range (4.1-9.8 x 10(9)/L) in all groups throughout the follow-up. In all patients of Groups 1, 2 and 3, circulating CD34+ failed to show statistically significant differences both as the absolute number and as the percentage at any time point compared to healthy controls. CONCLUSIONS: Bone marrow derived cell mobilization can not be detected after hepatectomy or during an acute decompensation on a cirrhotic liver. Under these circumstances liver regeneration can probably call upon mature hepatocytes and endogenous progenitor cells. The involvement of extrahepatic progenitors if any, is a rare and limited phenomenon.

Adult↗
PubMedDate not supplied

Surgery of differentiated thyroid carcinoma, lymph node metastases and locoregional recurrence.

Surgery of differentiated thyroid carcinoma is burdened with risk factors that significantly impact on prognosis, as age at diagnosis and tumor stage. Problems involved concern the extent of surgical resection and the indication for regional lymphadenectomy. As for the former, the most popular approach is total thyroidectomy "on principle" with neck lymphadenectomy. Lobectomy may represent an alternative to total thyroidectomy in low risk patients with unifocal papillary carcinoma 1 cm or less in size, or minimally invasive follicular carcinoma. As for lymphadenectomy, most authors do not agree with surgery "on principle" but rather "of necessity", that is, in presence of clinically evident lymphadenopathy and neck lymphadenectomy is the preferred surgical strategy. In most cases surgery is the treatment of choice of locoregional recurrence. Careful preoperative work-up and accurate surgical procedure are mandatory.

Carcinoma↗
PubMedDate not supplied

[Experimental model of hepatic tumor in the rat: description and results of intrahepatic implantation technique].

In order to investigate new therapeutic strategies for hepatocellular carcinoma (HCC), an animal model easily reproducible of hepatic tumor is necessary. Several techniques of intrahepatic tumor implantation have been reported in the literature. Many of them have the disadvantage of high rate of artificial neoplastic extrahepatic dissemination, both peritoneal and systemic. These drawbacks interfere with the evaluation of treatment efficacy. In this study we describe a modified technique of intrahepatic tumor implantation in the rat, previously reported by Yang in 1992, which is based on the insertion in the liver, after neoplastic tissue, of a piece of hemostatic sponge (Spongostan) that permits to significantly reduce the rate of artificial neoplastic dissemination. Nine ACI/T rats were used and Morris hepatoma 3924A was implanted in the right hepatic lobe. In all cases an intrahepatic tumor take was documented by MRI and by histological examination. No lung metastases were observed. In only one animal peritoneal and subcutaneous nodules were seen, likely due to a technique mistake. According to tumor growth curve it is possible to observe that, with this technique, a 1 cm tumor nodule is obtainable 10 days after the implantation, without extrahepatic metastases, easily detectable by imaging techniques such as MRI used in this study. In conclusion this modified technique of intrahepatic tumor implantation permits to obtain an intrahepatic tumor animal model which is easily reproducible and suitable for the evaluation of efficacy of experimental therapies for HCC.

Animals↗
PubMedDate not supplied

Incidence of genital tuberculosis in infertile patients submitted to diagnostic laparoscopy: recent experience in an Italian university hospital.

The incidence of genital tuberculosis is decreasing in industrialized countries. The authors report their experience in 254 patients with primary or secondary infertility. Out of 101 patients with a tubal factor of infertility, two patients were diagnosed as having tuberculosis by both endometrial biopsy and endometrial culture. In a third patient, even in the presence of laparoscopic findings suggesting genital tuberculosis Mycobacterium tuberculosis was isolated only from the urine.

Adult↗
PubMedDate not supplied

[Follow-up of residual renal function in patients with serious forms of posterior urethral valves].

We report the results of the trend of the residual renal function (RRF) of 15 patients with serious forms of hind urethral valves (HUV) which agreed to be long term regularly controlled after surgical correction at the Children's Surgical Hospital of Bologna University. The nephrological follow-up started in 1985 is based on a periodical control at least once a year, of some indicatives parameters of the glomerulars activity (creatinine clearance according Schwartz and creatinine reciprocal), of the tubular activity (urinary flux ml/kg/h, per cent fraction of Na excretion) and the dynamical test of the RRF started in 1991. The results although the low cases studies, are not statistically significant, the Authors underline the validity of the adopted method. Although of the simplified and/or indirect type, this is able to give clinically reliable informations of the renal functionality evolution avoiding particularly complex or invasive analysis.

Adolescent↗