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S Delia

Publications and source records attributed to S Delia.

At least 19 recordsLinked to original sources
PubMed2006

Pulmonary mycobacteriosis in a patient affected by mycosis fungoides: a diagnostic and therapeutic challenge.

Among patients with cutaneous T-cell lymphoma (CTCL), sepsis and pulmonary infections are the first cause of death. We report on a patient with CTCL who, after more than 10 years of aggressive antineoplastic treatments, showed extensive pulmonary infiltrations on staging CT scan. Repeated CT scans were inconclusive for an infectious process, and the patient was still asymptomatic. The diagnosis of mycobacteriosis was made on the microbiologic exam of bronchoalveolar lavage. Specific treatment was started with contemporary dosage reduction of chemotherapy. After six months of antibiotic treatment the pulmonary lesions improved, whereas CTCL progressed. Therefore, a new antineoplastic regimen was started obtaining control of CTCL, without aggravation of the pulmonary lesions. We highlight the diagnostic and therapeutic pitfalls encountered when pulmonary mycobacteriosis complicates the course and treatment of CTCL.

Adult↗
PubMed2001

An observational study on the epidemiology of respiratory tract bacterial pathogens and their susceptibility to four injectable beta-lactam antibiotics: piperacillin, piperacillin/tazobactam, ceftazidime and ceftriaxone.

Bacterial infections of the respiratory tract account for a large proportion of total medical consultations in general practice. In recent years, antibiotic resistance has increased alarmingly in a number of bacterial species that are common causes of these infections. The aim of this observational study was to determine the antibiotic resistance of microbial agents isolated from patients with acute or acutely exacerbated respiratory infections. Subjects recruited as potential sources of bacteria were either outpatients seen in a number of specialized clinics and hospital practices, or hospitalized patients. Overall, 648 consecutive patients (67% male, mean age 48.1+/-27.0 years) with infection of the upper or lower respiratory tract were observed during a 13-month period. A total of 551 pathogenic microbial strains were isolated and tested for their in vitro susceptibility to piperacillin, piperacillin/tazobactam, ceftazidime, and ceftriaxone. Among all isolates, the four most frequent pathogens were Pseudomonas aeruginosa (132 isolates, 24%), Streptococcus pyogenes (99 isolates, 18%), Staphylococcus aureus (93 isolates, 17%), and Klebsiella pneumoniae (46 isolates, 8%). The susceptibility of gram-positive isolates ranged from 97.5% to 95.1%, and no remarkable difference was found in the antibacterial activity of tested b-lactam antibiotics. The susceptibility of gram-negative isolates to piperacillin and piperacillin/tazobactam was also similar: 96.5% and 97.1%, respectively. In contrast, differences were found between piperacillin (or piperacillin/tazobactam) and either ceftazidime (p=0.003) or ceftriaxone (p<0.0003) in gram-negative isolates. We conclude that, despite the extensive use of beta-lactam antibiotics (piperacillin, ceftazidime, and ceftriaxone) in medical practice during the past three decades, the susceptibility of the most common pathogens involved in the etiology of upper and lower respiratory tract infections to these antibiotics is still high. In particular, bacterial resistance developed by gram-positive organisms against piperacillin is negligible and not alarming.

Adolescent↗
PubMed2001

Virulence factors in Vibrios and Aeromonads isolated from seafood.

Thirty-one isolates from seafood, identified as Aeromonas hydrophila (7), Aeromonas caviae (11), Vibrio parahaemolyticus (3), Vibrio fluvialis (5), Vibrio alginolytictus (3), Vibrio metschnikovii (1) and Vibrio damsela (1), were tested for possible virulence factors including extracellular hydrolytic enzymes, haemolysins, cytotoxins (VERO and HEp-2 cells) and adherence ability (HEp-2 cells). All the A. hydrophila strains were beta-haemolytic and produced cytotoxins as well as one strain of V. fluvialis. A. hydrophila and A. caviae strains, frequently adhesive, showed both aggregative and diffusive patterns, while five Vibrio strains only (three V. fluvialis, one V. parahaemolyticus and one V. alginolyticus) were adhesive with an aggregative pattern.

Aeromonas↗
PubMed2000

Quantitation of polyomavirus DNA by a competitive nested polymerase chain reaction.

A new method to quantitate small amounts of DNA in clinical specimens is described. The method, a nested competitive polymerase chain reaction (ncPCR), is able to quantitate between 10 and 10(6) copies per tube of polyomavirus DNA and shows good reproducibility when clinical samples are analysed. Throughout the whole procedure, an internal standard (IS) competes for the primers with the target DNA. The internal standard, a heterologous sequence containing the four primer recognition sites, was constructed using a modification of the 'MIMIC' approach that is useful for obtaining competitor sequences for any viral, bacterial or eukaryotic target. The ncPCR method for polyomavirus was applied to cerebrospinal fluids (CSF) from AIDS patients with progressive multifocal leukoencephalopathy (PML) and urine specimens from bone marrow transplant patients affected by haemorrhagic cystitis. The results obtained suggest that the ncPCR method is a sensitive and useful method for quantitating genomic load in clinical samples.

Acquired Immunodeficiency Syndrome↗
PubMed1999

Multiplex polymerase chain reaction for the simultaneous detection and typing of polyomavirus JC, BK and SV40 DNA in clinical samples.

A novel multiplex nested PCR (nPCR) method was developed for detecting and differentiating simultaneously the DNA of polyomaviruses JC, BK and SV40 in a single tube. In the first amplification step the same set of primers were used to amplify a conserved DNA region of the large T antigen gene of JCV, BKV and SV40. The second round of multiplex nPCR was carried out using a set of primers designed to render products of different size for each related virus. The thermocycling parameters and concentration of each reaction component were optimised systematically to achieve optimal specificity and sensitivity for the nPCR assay. The sensitivity of the method ranged between one and 10 copies of polyomavirus genome. Cerebrospinal fluid (CSF) was examined from AIDS patients with clinical and neuroradiological evidence of progressive multifocal leukoencephalopathy (PML) and CSF from AIDS patients with other neurological alterations. Urine specimens from bone marrow transplant recipients affected by haemorrhagic cystitis were also tested. The results obtained suggest that the assay is a good tool for supporting the diagnosis of polyomavirus infection and could be used for epidemiological purposes and in other studies in order to define better the role of polyomaviruses in human disease.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Advanced laboratory techniques for diagnosing Toxoplasma gondii encephalitis in AIDS patients: significance of intrathecal production and comparison with PCR and ECL-western blotting.

The polymerase chain reaction (PCR) for detection of cerebral spinal fluid (CSF) Toxoplasma gondii DNA was combined with the study of intrathecal antibody synthesis by antibody specific index calculation (ASI) and the detection of specific oligoclonal IgG bands (OCB) by affinity mediated immunoblotting (AMI) in 11 AIDS patients with T. gondii encephalitis (TE) and in 20 control patients with or without neurological disorders. Enhanced chemiluminescence (ECL) western-blot technique was employed to evaluate the antigenic specificity of CSF-IgG towards individual T. gondii antigens. PCR was positive in all TE patients which displayed brain-derived or blood-derived specific OCB, even when comparative ASI failed. Four TE patients had a unique anti-T. gondii OCB restricted to the CSF and a strong antibody response toward the 29 kDa band by ECL western blot. This response could be an important marker to discriminate TE from other opportunistic central nervous system (CNS) infections in the course of AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Detection of Pneumocystis carinii among children with chronic respiratory disorders in the absence of HIV infection and immunodeficiency.

A nested polymerase chain reaction (PCR) assay was investigated for detection of Pneumocystis carinii in 96 respiratory tract specimens from 82 children, of whom 28 were immunocompetent but with chronic lung disorders (CLD), eight had AIDS and P. carinii pneumonia (PCP), 16 had AIDS but no respiratory symptoms, and 30 were healthy immunocompetent children. Gomori methenamine silver stain (GMS) and indirect immunofluorescence assay (IFA) were performed in parallel. Of 36 specimens from children with CLD, 12 were P. carinii PCR-positive compared to 10 positive by GMS-IFA. Of eight specimens from children with AIDS and PCP, seven were P. carinii-positive by PCR and six by GMS-IFA, and of 22 specimens from HIV-positive children without respiratory symptoms, two were positive by PCR and none by GMS-IFA. P. carinii DNA was also detected by PCR in blood samples from four children with P. carinii-positive nasopharyngeal aspirates. Specimens from healthy children were negative for P. carinii by both PCR and GMS-IFA. Of the seven children with CLD, who were P. carinii-positive, two had clinical and microbiological improvement with co-trimoxazole treatment, two improved initially but relapsed, and one had P. carinii cysts persistently in follow-up specimens despite co-trimoxazole treatment. These results suggest an association between P. carinii and exacerbations of CLD in childhood, in the absence of HIV infection or other immunodeficiency syndromes.

AIDS-Related Opportunistic Infections↗
PubMed1998

Rhodococcus equi infection of monocytes/macrophages from human immunodeficiency virus (HIV)-infected patients and healthy individuals: evaluation of intracellular killing and nitric oxide production.

Monocytes/macrophages from human immunodeficiency virus (HIV)-infected patients had a defect in their ability to kill Rhodococeus equi in vitro, as compared with healthy HIV-seronegative individuals. Virulent and avirulent R. equi strains isolated from humans and horses showed no significant intracellular replicative differences within both HIV-positive and -negative monocytes/macrophages. Infection with R. equi induced the production of nitric oxide (NO) by monocytes/macrophages from healthy individuals, but not by cells from HIV-positive patients. The NO formation was significantly inhibited by L-NG-monomethyl arginine and arginase. However. neither competitive inhibition of NO synthesis from L-arginine with L-NMMA nor depletion of arginine with arginase altered the killing activity of human monocytes/macrophages against R. equi, thus suggesting that L-arginine:NO pathway is not required for the intracellular antirhodococcal mechanisms of human monocytes/macrophages.

AIDS-Related Opportunistic Infections↗
PubMed1997

Cerebrospinal fluid cytokines in patients with tuberculous meningitis.

The level of tumor necrosis factor (TNF)-alpha, soluble TNF receptors p75 (sTNFR-75) and sTNFR-55, interferon (IFN)-gamma, and interleukin (IL)-10 and IL-12 were measured in 59 cerebrospinal fluid (CSF) samples from 15 patients with tuberculous meningitis (TBM). TBM was associated with elevated concentrations of TNF-alpha, sTNFR-75, sTNFR-55, IFN-gamma, and IL-10, while CSF IL-12 was undetectable in all TBM patients. A significant correlation between cytokines and CSF adenosine deaminase activity was also found. The levels of TNF-alpha did not decrease over time, being still detectable in the CSF 16 months after starting antibiotic therapy, whereas IFN-gamma along with anti-inflammatory mediators sTNFR-75, sTNFR-55, and IL-10 remained elevated in the CSF for 4-8 months. The chronic release of cytokines in the CSF compartment was related neither to the TBM stage nor to the clinical outcome of the disease, thus suggesting the presence of a continuous activity of the inflammatory process at the site of infection.

Adenosine Deaminase↗
PubMed1996

Serologic responses to Rhodococcus equi in individuals with and without human immunodeficiency virus infection.

Thirty healthy blood donors, 15 workers from horse-breeding farms, 69 human immunodeficiency virus (HIV)-negative persons at risk for HIV infection, 125 HIV-infected subjects without Rhodococcus equi infection, and nine HIV-infected patients with Rhodococcus equi pneumonia were evaluated in order to detect serum antibodies to Rhodococcus equi precipitate-soluble antigen by an enzyme immunoassay (EIA). Whereas EIA values for healthy donors, horse farm workers, individuals at risk for HIV infection, and HIV-positive subjects without Rhodococcus equi infection were comparable, HIV-infected patients with rhodococcal disease had significantly higher Rhodococcus equi antibody levels (p < 0.0001). The clinical outcome of Rhodococcus equi pneumonia was more severe in subjects who had low levels of specific antibodies, whereas patients who recovered had elevated Rhodococcus equi antibody levels over time. Immunoblot studies showed that both Rhodococcus equi-infected patients and foals recognized a protein band of approximately 60 kDa in the Rhodococcus equi precipitate-soluble antigen. On the other hand, the Rhodococcus equi-infected patients did not react with the diffuse 15 to 17 kDa virulence-associated proteins that represent important virulence factors both in mice and horses.

Actinomycetales Infections↗
PubMed1996

Chlamydia pneumoniae seroprevalence among HIV-1-infected and uninfected people with known HIV risk factor.

OBJECTIVE: To evaluate the prevalence of Chlamydia pneumoniae antibodies in an Italian population of HIV-infected and uninfected individuals in relation to the presence of HIV risk factors. DESIGN AND METHODS: A prospective evaluation of C. pneumoniae microimmunofluorescence immunoglobulin (Ig) G and IgM titres, in relation to sex, age, HIV clinical stage, and the presence of different HIV acquisition risk factors. SETTING: The Department of Infectious and Tropical Diseases, a secondary and tertiary care institution in the 'La Sapienza' University of Rome, during 1994 and 1995. PARTICIPANTS: HIV-infected and uninfected subjects (n = 322), all of them without respiratory symptoms. RESULTS: A statistically significant higher C. pneumoniae seroprevalence was found to be related, by multivariate analysis, to sex, age, and presence of HIV risk factor, but not to the presence of HIV infection itself. Among HIV-positive subjects, C. pneumoniae seroprevalence appeared to decrease with absolute CD4+ cell count and was low in Centers for Disease Control and Prevention (CDC) stage C of HIV infection. Furthermore, high C. pneumoniae IgG titres (> or = 1:512) were not found in subjects with CDC stage C disease or in those with low CD4+ cell count (< 200 x 10(6)/l). CONCLUSION: C. pneumoniae seroprevalence is higher in injecting drug users and in subjects with promiscuous heterosexual activity. A previous report of a higher C. pneumoniae seroprevalence among HIV-1-infected subjects (in relation to the normal population) was probably due to the presence of HIV risk factor and not to the HIV infection itself. HIV-infected subjects seem to have progressively lost their C. pneumoniae IgG antibodies in middle and advanced stages of HIV infection. High C. pneumoniae IgG titres are rarely found in advanced stage HIV-infected patients.

AIDS-Related Opportunistic Infections↗
PubMed1996

Cytomegalovirus in bronchoalveolar lavage specimens from patients with AIDS: comparison with antigenaemia and viraemia.

Pulmonary infection with cytomegalovirus (CMV) is a well recognised complication of AIDS. It is often possible to detect CMV-infected cells in bronchoalveolar lavage (BAL) specimens with monoclonal antibodies, but the clinical significance of their presence remains unclear. To investigate this, 24 AIDS patients were tested for CMV antigenaemia and viraemia, in addition to CMV detection in BAL. CMV was detected in the BAL of nine patients (38%), five with clinical and laboratory evidence of pulmonary infection and four without pulmonary involvement. Blood samples positive for CMV antigen were observed in two patients with CMV-positive BAL specimens and, in both cases, antigenaemia resolved without therapy. No case of viraemia was detected. Pneumocystis carinii was detected concomitantly with CMV in the BAL of four of the patients with pulmonary involvement and in one without signs of pulmonary infection. These data suggest that CMV-positive BAL results are of limited significance in the diagnosis of CMV pneumonia in AIDS patients, unless associated with high levels of antigenaemia or viraemia and compatible clinical symptoms.

AIDS-Related Opportunistic Infections↗
PubMed1995

Diagnosis of Toxoplasma gondii infection in AIDS patients by a tissue-culture technique.

Toxoplasma gondii infection was investigated in 14 AIDS patients with neurological involvement who showed clinical and computer tomographic scan signs suggestive of toxoplasmic encephalitis or extraneuronal localization suggestive of toxoplasmic infection. Blood, lung secretion (bronchoalveolar lavage and/or induced sputum sample) and cerebral spinal fluid (CSF) samples were cultured, and the results compared with the results of direct examination by Giemsa and by immunofluorescence of lung secretions and CSF. Toxoplasma gondii were observed directly in only four patients by immunofluorescence in bronchoalveolar lavage, induced sputum and CSF samples, and in three of these patients by Giemsa staining of bronchoalveolar lavage and CSF smears. In contrast, parasites were detected after 48 h in blood cultures from 11 of the 14 AIDS patients, in CSF cultures from eight of them and also in cultures of bronchoalveolar lavage and induced sputum from the six patients with respiratory and radiological features indicative of lung tissue damage. The findings indicate the value of tissue culture for diagnosis of toxoplasmosis as well as for monitoring the effects of treatment and also indicate that culture of induced sputum could be a powerful tool in establishing the incidence of pulmonary toxoplasmosis in AIDS patients.

AIDS-Related Opportunistic Infections↗
PubMed1995

Evidence of Pneumocystis carinii in cell line cultures infected with peripheral blood mononuclear cells isolated from AIDS patients with P. carinii pneumonia.

The detection of Pneumocystis carinii was investigated in an in-vitro system consisting of a human lung epithelial cell line (A-549) inoculated with infected peripheral blood mononuclear cells (PMBC) from HIV-infected patients with proven or suspected P. carinii pneumonia (PCP), and from HIV-negative patients with other lung infections. Supernates from cultures were sampled daily and evaluated for the presence of P. carinii by Giemsa and immunofluorescence staining. P. carinii was isolated from 98 (95.1%) of 103 culture supernate samples from patients with proven pneumocystosis and 45 (66.1%) of 68 from patients with suspected PCP 40 or 72 h after PBMC inoculation. This system has been shown to support the growth of P. carinii but did not seem to be adequate for the production of large numbers of organisms, although long-term survival in vitro for up to 3 weeks was observed. Recovery of P. carinii from infected PBMC strongly supports previous observations about its ability to disseminate haematogenously and could represent a further advance in understanding the pathogenesis and diagnosis of PCP.

AIDS-Related Opportunistic Infections↗
PubMed1994

Myelin degrading activity in the CSF of HIV-1-infected patients with neurological diseases.

Degradation of purified myelin basic protein (MBP) was studied by SDS gel electrophoresis after addition of CSF samples obtained from HIV-1-infected patients. An increase in MBP degradation was detected in patients with neurological complications, such as AIDS dementia complex (ADC) or progressive multifocal leukoencephalopathy (PML), when compared with patients with no neurological symptoms (NA) or with other neurological opportunistic infections (OI). In the ADC and PML patients, in addition to CSF proteolytic activity, an increase in CSF-MBP levels and presence of white matter lesions were also observed by neuroimaging (MRI). In other opportunistic infections of the brain, MBP levels but not anti-MBP proteolytic activity increased. Results suggest the involvement of proteases in the virus-induced demyelination.

AIDS Dementia Complex↗
PubMed1994

Cytomegalovirus encephalitis in two patients with AIDS receiving ganciclovir for cytomegalovirus retinitis.

Cytomegalovirus (CMV) encephalitis has been reported with increasing frequency in patients with AIDS. Nevertheless, the management of CMV-related encephalitis appears to be problematic and data in the literature on the clinical efficacy of ganciclovir therapy is sparse and controversial. We describe two patients with AIDS who developed CMV encephalitis while receiving ganciclovir maintenance therapy for CMV retinitis. Moreover, there was no improvement in neurological status or virological and radiological response during a further induction course of ganciclovir. These observations suggest that the currently recommended therapeutic protocols with ganciclovir are not effective in the prevention and treatment of CMV encephalitis in patients with AIDS.

AIDS-Related Opportunistic Infections↗