Effects of antiretroviral therapy on proprotein convertase subtilisin/kexin 9: focus on lipids, inflammation and immunovirological parameters.

OBJECTIVES: Plasma levels of proprotein convertase subtilisin/kexin type 9 (PCSK9), a major regulator of cholesterol metabolism, have been reported to have an increasing trend in people living with HIV (PLWH) compared with controls. We assessed the impact of different antiretroviral (ARV) regimens on plasma PCSK9 levels as well as plasma lipids, systemic inflammation and immunovirological parameters. METHODS: Eighty HIV-positive ARV therapy (ART)-naïve PLWH and 40 uninfected controls were retrospectively enrolled. At baseline and 3, 6 and 12 months after ART initiation, plasma PCSK9 levels, lipids, high-sensitivity C-reactive protein (hs-CRP), HIV-1 RNA levels and CD4 T-cell count were measured. RESULTS: Baseline PCSK9 levels were significantly more elevated in PLWH and were associated with HIV-1 RNA levels (P < 0.001), CD4 T-cell counts (P < 0.001), triglycerides (P < 0.001) and high-density lipoprotein (HDL) cholesterol (P < 0.001), but not with total cholesterol, low-density lipoprotein (LDL) cholesterol and lipoprotein(a) levels. The prescription of ART was paralleled by significant decreases in plasma PCSK9 and hs-CRP levels, and increases in total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides and lipoprotein(a), independent of regimen. CONCLUSIONS: PCSK9 levels, along with systemic inflammation, were progressively reduced following the initiation of an effective ART. However, at the end of the study PCSK9 levels remained higher than in controls and did not correlate with any of the lipid variables.

Five year experience of the treatment of squamous cell carcinoma of the anus.

OBJECTIVES: The best treatment of early stage anal squamous cell carcinoma (SCC) is under debated. Wide local excision (WLE) may be considered adequate for stage 1 anal margin cancer. This study demonstrates our experience in treatment of patients with SCC over 5 years. PATIENTS AND METHODS: We conducted a retrospective study of patients who had undergone anal screening or anal cancer surveillance between October 2010 and 2015 in our department. Each patient underwent anal Pap test, HPV test PCR HPV DNA and cytology by Thin Prep. The examinations were performed by Proctostation THD©. Data were collected and analysed. RESULTS: We included 25 patients, 16 male (64%) and 9 female (36%). Twenty-four patients had SCC and 1 patient had adenocarcinoma. Of this cohort: 10 underwent chemoradiotherapy (CRT) because T3-4 N1-2 M0, 13 underwent only surgery because T1/T2 and 2 patients had CRT and surgery because they already have had anal cancer treated in the past with CRT. Seventeen patients (68%) of this cohort, including 5 with micro-invasive SCCs, had regular follow-up without recurrences. Four patients (17%) died from metastatic disease and 4 patients (17%) had recurrent disease. CONCLUSIONS: In this small cohort we demonstrated satisfactory results in treatment of SCCs, underlining the effective role of surgery in early stages of SCC. Screening program and follow up were fundamental to identify early stage and recurrent disease. Also we found the High-resolution video-proctoscopy a valid diagnostic tool.

FXR activation improves myocardial fatty acid metabolism in a rodent model of obesity-driven cardiotoxicity.

BACKGROUND AND AIMS: Obesity-driven lipotoxicity is a risk factors for cardiovascular disease. The Farnesoid X Receptor (FXR) is a bile acids sensor and member of the nuclear receptor superfamily. Activation of FXR lowers plasma triacylglycerols and glucose levels through a mechanism that involves both the repression of key regulatory genes in the liver and the modulation of insulin sensitivity in peripheral tissues. In the present study we have investigated whether administering obese (fa/fa) Zucker rats, a genetic model of obesity associated with dyslipidemia and insulin resistance, with an FXR ligand protects against lipid-induced cardiomyopathy. METHODS AND RESULTS: FXR is expressed in neonatal cardiomyocytes and the treatment with FXR agonists, chenodeoxycholic acid (CDCA), and GW4064, increased the mRNA expression of FXR and its canonical target gene, the small heterodimer partner (SHP), as well as proliferator-activated receptor alpha PPARα, acyl-CoA oxidase (AOX) and pyruvate dehydrogenase kinase (PDK-4). Feeding obese fa/fa rats with CDCA, 12 weeks, reduced hyperinsulinemia and hyperlipidaemia. The histological-pathological analysis of hearts demonstrated that treatment with the FXR ligand reduced lipid heart content decreased the rate of apoptosis, fibrosis scores and restored heart insulin signalling. Chronic CDCA administration, in the heart, induced PPARα and PPARα-regulated genes involved in ß-oxidation. CONCLUSION: FXR agonism exerts beneficial effects in a genetic model of lipid-induced cardiomyopathy. The striking benefit of this therapy on cardiac function in this model warrants an effort to determine whether a counterpart of this activity translates in human settings.

Management of hepatitis B virus reactivation in patients with hematological malignancies treated with chemotherapy.

INTRODUCTION: Hepatitis B virus (HBV) reactivation is a major cause of morbidity and mortality in patients with hematological malignancies who receive cytotoxic chemotherapy. We have therefore carried out a prospective observational study out to assess the incidence, prevalence, and clinical course ina cohort of these patients. METHODS: HBV and HCV markers and liver function indices were monitored prospectively in 318 consecutive patients(171 males, 147 females; mean age 57 years) with hematological malignancies, who had been referred to the Hematology Division, Perugia University, between October 2005 and March 2007 and followed up for at least 6 months. RESULTS: At diagnosis, 32 patients (10%) had received HBV vaccination; 30 were responders. At least one HBV marker was positive in 70/318 patients (22%): 14 (20%) were HBsAg-positive(HBV surface antigen-positive), 13 (19%) were only anti-HBc positive (antibodies to HB core antigen), and 43(61%)were anti-HBc and anti-HBs positive. Twelve HBsAg+ patients received nucleoside/nucleotide analogs (adefovir [six patients],lamivudine [four], and combined adefovir/lamivudine[two non-responders to lamivudine]). After 6 months of therapy, HBV-DNA was negative and transaminases were normal in nine of these 12 patients (adefovir [six], lamivudina[two], adefovir + lamivudina [one]). Seroreversion was achieved in 3/13 patients (23%) who were only anti-HBc positive;all were on rituximab therapy and received adefovir. Seroreversion was not observed in any of the 43 patients who were anti-HBc- and anti-HBs positive. CONCLUSIONS: Essential to the management of patients with hematological malignancies undergoing chemotherapy are surveillance and prophylaxis of HBV infection together with prompt administration of nucleoside/nucleotide analogs in cases of reactivation and/or seroreversion.

Occult hepatitis B virus infection in a cohort of HIV-positive patients: correlation with hepatitis C virus coinfection, virological and immunological features.

BACKGROUND: An evaluation of the prevalence of occult hepatitis B virus (HBV) infection in HIV-positive individuals is important as HBV infection may have an impact on the outcome of the liver disease in these patients. MATERIALS AND METHODS: Of the 1,593 HIV-positive subjects enrolled in the Italian Cohort Naïve Antiretroviral (ICONA) program, 175 (10.9%) were selected for inclusion in the study on the basis of hepatitis B surface antigen (HBsAg) negativity and antibody to hepatitis B core antigen (anti- HBc) positivity; 101/175 (58%) were also anti-hepatitis C virus (HCV) positive. HBV-DNA was detected in plasma using a highly sensitive PCR assay (detection limit: 2.6 copies/ml). Two different genomic regions were assayed. Quantification was performed by real-time PCR. The HBV genotype was determined in 20 cases with occult HBV infection. Data on the antiretroviral therapy (ART) regimen was obtained in 169 individuals: 53 (31.4%) patients were ART-naive, 46 (27.2%) were under ART without lamivudine or tenofovir, and the remaining 70 (41.4%) were under ART including lamivudine or tenofovir. RESULTS: 27/175 (15%) patients had detectable HBV-DNA in their plasma: 21/101 (21%) were anti-HCV positive and 6/74 (8%) were anti-HCV negative. Genotype D was invariably found in the 20 cases analyzed. Occult HBV infection was significantly higher in HCV-coinfected subjects: adjusted OR 5.02, 95% CI 1.31-19.26, p = 0.02. The value was not associated with immune status, HIV load, or ART regimen. CONCLUSIONS: In relation to the high prevalence of occult HBV infection, particularly in HIV/HCV-coinfected individuals, it is necessary to clarify the clinical impact of this cryptic infection by monitoring HBV-DNA in plasma using the correct approach. Similarly to HBsAg-positive individuals of the Mediterranean area, HBV genotype D is invariably detected in this cohort of HIV-infected patients with occult HBV infection.

Daily bathing with 4% chlorhexidine gluconate in intensive care settings: a randomized controlled trial.

OBJECTIVES: To investigate whether daily bathing with a soap-like solution of 4% chlorhexidine (CHG) followed by water rinsing (CHGwr) would decrease the incidence of hospital-acquired infections (HAI) in intensive care settings. METHODS: Randomized, controlled trial; infectious diseases specialists were blinded to the intervention status. All patients admitted to the Intensive Care Unit (ICU) and to the Post-operative Cardiosurgical Intensive Care Unit (PC-ICU) of the University Hospital of Perugia were enrolled and randomized to the intervention arm (daily bathing with 4% CHGwr) or to the control arm (daily bathing with standard soap). The incidence rate of acquisition of HAI was compared between the two arms as primary outcome. We also evaluated the incidence of bloodstream infections (BSI), central-line-associated BSI (CLABSI), ventilator-associated pneumonia (VAP) and catheter-associated urinary tract infections (CAUTI), and 4% CHGwr safety. RESULTS: In all, 449 individuals were enrolled, 226 in treatment arm and 223 in control arm. Thirty-four individuals of the 226 (15%) and 57 (25.6%) suffered from at least an HAI in the intervention and control arms, respectively (p 0.008); 23.2 and 40.9 infections/1000 patient-days were detected in the intervention arm and control arm, respectively (p 0.037). The incidence of all bloodstream infections (BSI plus CABSI) was significantly reduced in the intervention arm (9.2 versus 22.6 infections/1000 patient-days, p 0.027); no differences were observed in the mortality between the two arms. CONCLUSIONS: Daily bathing with 4% CHGwr significantly reduced HAI incidence in intensive care settings. CLINICALTRIAL. GOV REGISTRATION: NCT03639363.

Topical cidofovir for severe warts in a patient affected by AIDS and Hodgkin's lymphoma.

We describe a 42-year-old man with AIDS and Hodgkin's lymphoma whose severe and recalcitrant cutaneous warts resolved following treatment with local 1% cidofovir. Clinically significant improvements were observed in a two-week period of therapy. In advanced HIV disease complicated by additional haematological malignancy, cutaneous warts may be difficult to treat and present a challenge for the attending physicians. In similar clinical condition topical anti-human papillomavirus therapy may prove to be safe and curative.

Treatment of post-traumatic hand Staphylococcus aureus osteomyelitis with oral linezolid.

The Authors report on the use of linezolid for the treatment of three patients with osteomyelitis. All three patients had post-traumatic multisensitive hand bone methicillin-susceptible Staphylococcus aureus osteomyelitis, which did not respond to antimicrobial regimens including drugs in vitro active against the isolated strains. Clinical cure and microbiologic eradication was obtained with oral linezolid in all three patients. Linezolid was well tolerated. Mild thrombocytopenia was observed in one patient at the end of the third week of treatment and it was promptly resolved after the discontinuation of linezolid. Linezolid minimum inhibitory concentrations (MICs) consisted of 2 mg/l for all three S. aureus isolates while the bactericidal activity in vitro was not present up to the linezolid concentration of 32 mg/l. In spite of a lack of in vitro bactericidal activity, linezolid was effective in curing the patients and eradicating the infection. Trough and peak plasma concentrations of linezolid were above the MICs of the isolates. These values ranged from 3.93 to 14.95 mg/l at trough and 5.03 to 25.91 mg/l at peak. The oral bioavailability, pharmacokinetic profile and antibacterial spectrum of linezolid make this oxazolidonone antimicrobial an attractive drug for the treatment of chronic osteomyelitis. Prolonged administration requires careful surveillance for side effects, until these complications are better understood.

Clinical efficacy and tolerability of caspofungin in a renal transplant patient with Aspergillus flavus lung infection: case report.

Organ transplant recipients are at increased risk for severe invasive aspergillosis, and amphotericin deoxycholate has been the standard treatment for many years. Currently, however, lipid formulations are preferred due to their few side effects. Also, a number of new antifungal drugs have been developed including new azoles and echinocandins. Caspofungin is the first of the echinocandin derivatives patented to treat patients with invasive aspergillosis who are refractory or intolerant to other therapies. A renal transplant patient on immunosuppressive treatment with chronic hepatitis B virus infection was admitted with fever, hemophthisis and lung consolidation, diagnosed to be probably caused by Aspergillus flavus. The patient developed cholestatic hepatitis most likely related to itraconazole. Clinical failure and in vitro itraconazole resistance of the isolate was also documented while the patient was receiving itraconazole at a reduced dosage. Caspofungin was administered once a day as ambulatory treatment and was well tolerated. Clinical improvement was observed after 6 weeks of treatment and no hepatic toxicity was documented. Caspofungin seems to be a potentially useful antifungal agent in renal transplant patients with invasive aspergillosis. Further evaluation of the efficacy of caspofungin is needed.

Fatal haemolytic uraemic syndrome in an AIDS patient with disseminated adenovirus and cytomegalovirus co-infection.

We describe a fatal case of haemolytic uraemic syndrome in a young woman with AIDS, and disseminated adenovirus (ADV) and cytomegalovirus (CMV) co-infection. We hypothesize that ADV/CMV co-infection may have a causative role in this clinical picture.

The pp65 antigenaemia test as a predictor of cytomegalovirus-induced end-organ disease in patients with AIDS.

OBJECTIVE: To evaluate the predictive value of pp65 antigenaemia quantitative test for cytomegalovirus (CMV) end-organ disease in patients with advanced HIV infection. DESIGN AND PATIENTS: A prospective study in AIDS patients or HIV-infected subjects with CD4 count < 150 x 10(6)/l or CD4 percentage < 10% was carried out. Patients with a history of CMV disease or positive viraemia or antigenaemia tests and subjects under anti-herpes suppressive therapy were excluded. Clinical, ophthalmoscopic, biochemical and virological (antigenaemia test) evaluations were performed at baseline and every 1-3 months until the onset of CMV end-organ disease. SETTING: Institutional tertiary care centre. RESULTS: Forty-nine patients were evaluable for this study. End-organ disease was observed in 13 patients, 11 with at least one positive test, two with persistently negative assays. Thirteen patients without CMV disease had at least one positive test, whereas 23 always had negative tests. The 12-month Kaplan-Meier estimate of the incidence of CMV disease in our population was 30.9% and was 75% in antigenaemia-positive subjects. The negative predictive value (NPV) of the test was 92%, and the positive predictive value (PPV) was 45.8%. However, the NPV of quantitative (> 20 cells) antigenaemia assay was 92.1% and the PPV was 90.9%. CONCLUSIONS: The antigenaemia test is a quick, simple and easy to perform assay for diagnosing CMV infection. The NPV is fairly good, as is the PPV when the quantitative method (> 20 positive cells) is used. This test could be used as an alternative to polymerase chain reaction in order to select patients at higher risk of CMV disease who can be treated with pre-emptive anti-CMV therapy.

Normalization of anti-cryptococcal activity and interleukin-12 production after highly active antiretroviral therapy.

OBJECTIVE: To investigate the effect of highly active antiretroviral treatment (HAART) on antifungal and secretory functions of polymorphonuclear leukocytes (PMNL) from HIV-infected patients with high viral load. DESIGN: Antifungal activity, oxygen-dependent mechanisms and interleukin (IL)-12 secretion were evaluated in PMNL from HIV-infected patients before and 3 months after commencing HAART. METHODS: PMNL antifungal activity was evaluated by effects on fungal colony-forming units. Superoxide anion (O2-) production was determined by superoxide dismutase reduction and IL-12 was determined by enzyme-linked immunosorbent assay in supernatant fluids of PMNL cultured for 18 h. RESULTS: PMNL from HIV-infected patients showed dysregulation of antimicrobial and secretory functions. A selective defect in antimicrobial activity against encapsulated Cryptococcus neoformans correlated with baseline O2- overproduction, which drastically decreased upon microbial stimulation. Similarly, constitutive secretion of IL-12 was blocked by exposure to microbial products. PMNL analysed after 3 months of HAART showed restoration of antimicrobial activity against encapsulated C. neoformans, reduction in O2- formation by unstimulated cells and restoration of oxidative burst after appropriate stimulation, and reduction of IL-12 hypersecretion. CONCLUSIONS: PMNL from HIV-infected patients with high viral load have impaired function; HAART normalizes antimicrobial and secretory activities. The effects of HAART on innate immunity provide new prospects for reduction of HAART-mediated opportunistic infections.

Inhibition of fungicidal activity of polymorphonuclear leukocytes from HIV-infected patients by interleukin (IL)-4 and IL-10.

OBJECTIVE: To investigate the effect of human recombinant interleukin (hrIL)-4 or hrIL-10 on the functional status of polymorphonuclear leukocytes (PMNL) from normal subjects and HIV-infected patients. DESIGN: In an in vitro system we studied the effect of hrIL-4 or hrIL-10 on phagocytosis, fungicidal activity and superoxide anion production by PMNL. METHODS: PMNL were treated in vitro with hrIL-4 or hrIL-10 or their combination for 6 h and then candidacidal activity was evaluated in a colony-forming unit inhibition assay. Superoxide anion generation by PMNL was measured in the presence or absence of preopsonized zymosan or Candida albicans. RESULTS: Treatment in vitro with hrIL-4 or hrIL-10 of PMNL for 6 h was able to impair candidacidal activity of neutrophils in both normal or HIV-infected patients. The inhibitory effect was time- and dose-dependent and was more evident in PMNL from HIV-infected subjects, and reflected in these latter cells a decrease of superoxide anion generation. The impairment of candidacidal activity in PMNL from HIV-infected patients was accompanied by survival of the yeasts shown by budding formation into phagosomic organelles of cytokine-treated PMNL. CONCLUSIONS: Our data highlight new biological effects of IL-4 and IL-10 evidenced by suppressed effector function of neutrophils; this phenomenon is emphasized in HIV-infected patients suggesting a role for these cytokines in mediating increased susceptibility to microbial infection during AIDS progression.

Antibody to capsular polysaccharide enhances the function of neutrophils from patients with AIDS against Cryptococcus neoformans.

OBJECTIVE: To determine the contribution of anti-glucuronoxylomannan monoclonal antibody (MAb18B7) to the fungicidal capacity of polymorphonuclear leukocytes (PMNL) from HIV-infected patients towards Cryptococcus neoformans. DESIGN: Killing activity and superoxide anion generation were evaluated in the presence or absence of MAb18B7 in an in vitro system. METHODS: Killing activity was determined by colony forming unit inhibition assay. Superoxide generation was measured in the presence or absence of zymosan, C. neoformans, or Candida albicans. CD16, CD32, and CD64 molecules on PMNL were evaluated by cytofluorometric analysis. RESULTS: MAb18B7 strongly influenced the phagocytic and killing activities against encapsulated C. neoformans and consistently enhanced superoxide anion generation. Expression of CD16, and to a lesser extent CD64, on PMNL was required for MAb18B7-induced superoxide generation. By blocking CD16 and CD64 molecules with anti-CD16 and anti-CD64 MAb, a significant down-regulation of MAb18B7-induced fungicidal activity was observed. CONCLUSIONS: Our results demonstrate that MAb18B7 selectively enhances the killing mechanisms of PMNL from HIV-infected patients against encapsulated C. neoformans. The availability of CD16 and CD64 molecules on PMNL plays a critical role.

Granulocyte-macrophage colony-stimulating factor and fluconazole enhance anti-cryptococcal activity of monocytes from AIDS patients.

OBJECTIVE: To investigate the effect of human recombinant granulocyte-macrophage colony-stimulating factor (hrGM-CSF) and fluconazole on anti-cryptococcal activity of monocytes from AIDS patients and normal subjects. DESIGN: The effect of GM-CSF and fluconazole on fungistatic and fungicidal activity of monocytes was studied in an in vitro system. METHODS: Monocytes were treated in vitro with hrGM-CSF and fluconazole or either agent alone for 24 or 48 h, and fungistatic and fungicidal activity was evaluated in a colony-forming unit inhibition assay. CD11b/CD18 expression in monocytes was measured by flow cytometry analysis. Superoxide anion generation by peripheral blood monocytes was measured in the presence of pre-opsonized zymosan. RESULTS: Defective antifungal capacity of monocytes from AIDS patients was observed. GM-CSF treatment of monocytes from AIDS patients increased fungistatic activity, and the combination of hrGM-CSF and fluconazole resulted in fungicidal activity. The mechanisms involved in the GM-CSF-mediated effect appeared to be mediated by (i) enhancement of phagocytic activity, (ii) increase of superoxide anion generation, and (iii) upregulation of CD11b/CD18 expression on the monocyte surface. CONCLUSIONS: Our data highlight the effect of GM-CSF on anti-cryptococcal activity of human monocytes and show a synergistic effect of GM-CSF with fluconazole, suggesting a new therapeutic strategy in the treatment of cryptococcosis.

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.

Post operative surveillance of human hydatidosis: evaluation of immunodiagnostic tests.

We investigated the kinetics of antibodies detected by indirect hemagglutination (IHA), IgE Elisa and immunoelectrophoresis (IEP) in patients with hydatid disease operated on and continuously followed in the pre-operative and post-operative periods. In the pre-operative phase the IgE Elisa test was found to be adequately sensitive (68.4%) compared with IHA (79%), with a ratio of IgE Elisa/IHA positivity of 87%, while IEP was positive in 55.3% of cases (IEP/IHA ratio = 70%). During post-operative follow-up IHA became negative late in patients who were cured (7 out of 11 were still positive after 4 yrs), whereas IEP and IgE Elisa became negative within 2 yrs of operation (apart from 1 patient with a persisting positive IgE Elisa 3 yrs later). However, IgE Elisa appeared clearly more sensitive in revealing postoperative recurrences (13 out of 13 patients had positive IgE Elisa, vs. 6 out of 13 IEP).

Monocyte dysfunction in patients with acquired immunodeficiency syndrome (AIDS) versus Cryptococcus neoformans.

In the present study we investigated the response of monocytes from AIDS patients, susceptible to cryptococcosis (<200 CD4 cells/microl), against Cryptococcus neoformans. Different patterns of response were observed in these cells compared to cells from healthy donors. In particular, fungicidal activity versus this fungus was impaired; this phenomenon could be due to the difficulty of monocytes to internalize C. neoformans in the presence of an intact complement system. Impairment of complement receptor type 3 and direct involvement of this receptor in phagocytosis of C. neoformans were found in monocytes from AIDS patients, which may account for the difficulty in phagocytosis of the fungus. Also, superoxide anion production was dramatically reduced in monocytes from AIDS patients. An increase of spontaneous tumor necrosis factor (TNF) production was evidenced after in vitro addition of C. neoformans. However, this did not activate the antifungal capacity of monocytes from AIDS patients. Moreover, cryptococcus-laden monocytes from AIDS patients were able to induce only a weak response of autologous T-lymphocytes. Hence, monocyte dysfunction could play a part in the progression of cryptococcosis in AIDS.

[Susceptibility of P. aeruginosa and enterobacteriaceae isolated from 1986 to 1994 in the Microbiology laboratory of the Infectious Diseases Institute of Perugia University]. / Variazione della sensibilita agli antibiotici di Pseudomonas aeruginosa e di alcune specie di enterobatteri isolati nel laboratorio di Batteriologia dell'Istituto di Malattie Infettive dell'Università di Perugia dal 1986 al 1994.

From 1986 to 1994, 812 P. aeruginosa, 1997 E. coli, 437 P. mirabilis, 400 Klebsiella spp., 238 Enterobacter spp., 130 Serratia spp. strains were isolated from clinical materials in the Microbiology laboratory of the Infectious Diseases Institute of Policlinico Monteluce, Perugia University. During the study period the Authors observed the following variations in the susceptibility patterns: increased resistance of P. aeruginosa to piperacillin from 20.8% to 27.2% (P<0.05), amikacin from 11.9% to 17.5% (P<0.05), netilmicin from 11.8% to 28.6% (P<0.01), pefloxacin from 74.4% to 87.8% (P<0.01); E. coli to norfloxacin, ciprofloxacin and pefloxacin, respectively from 1.3% to 3.6% (P<0.001), from 1.5% to 3.6% (P<0.05) and from 3.2% to 9% (P<0.001); Serratia spp. to ceftazidime from 14% to 33.3% (P<0.05); Enterobacter spp. to norfloxacin from 5.1% to 13.6% (P<0.05), cotrimoxazole from 12.8% to 23.5% (P<0.05) and chloramphenicol from 19.4% to 31.8% (P<0.05). Moreover cephalotin resistant strains of E. coli decreased from 29.3% to 21.3% in the last 4 years (P<0.001).