Environmental surveillance and molecular investigation of Legionella spp. in Apulia, in the years 2008-2011.

Legionella spp. is considered an emerging microorganism involved in aquatic environments contamination and cause of Legionnaires' disease. The aims of the study are to evaluate the level of contamination of Legionella spp. in the water system of the largest Hospital of Apulia region during a 4-year surveillance and to establish, by molecular method, the presence of a predominant genotype of L. pn. sg 1. The results showed that Legionella spp. was present in 36% of water samples with Legionella pneumophila serogroup 1 (L. pn. sg 1) the most prevalent species and serogroup and the wards most contaminated are the high risk units. In addition, despite four main clones of L. pn. sg 1 were identified, a predominant genotype existed. In conclusion the study demonstrates the necessity for periodic evaluation on hospitals water system to assess the potential contamination of Legionella spp., performing decontamination in the presence of bacterial contamination, even low, in particular in high risk wards. Moreover, the switching of the disinfection methods may be suggested in order to prevent resistance phenomenon by some L. pn. sg 1 clones.

Epidemiology of invasive fungal infections in the intensive care unit: results of a multicenter Italian survey (AURORA Project).

PURPOSE: The aims of this study are to evaluate the epidemiology of invasive fungal infections (IFIs) in patients admitted to an intensive care unit (ICU) in Southern Italy and the in vitro antifungal susceptibility of isolates. METHODS: A surveillance program was implemented in 18 ICUs. IFI cases were recorded using a standardized form. RESULTS: A total of 105 episodes of IFIs occurred in 5,561 patients during the 18-month study. The main infections were caused by yeasts, more than filamentous fungi (overall incidence of 16.5 cases per 1,000 admissions and 2.3 cases per 1,000 admissions, respectively). The overall crude mortality rate was high (42.8 %), particularly for mold infections (61.5 %). All yeast infections were Candida bloodstream infections. Over half (59.8 %) were caused by Candida non-albicans, with C. parapsilosis being the most common (61.8 %). In the multivariate model, trauma admission diagnosis, prolonged stay in the ICU, and parenteral nutrition were independently associated with candidemia due to C. parapsilosis [odds ratio (OR) 3.5, (1.8-5.2); OR 3.5, (1.02-3.5); OR 3.6, (1.28-6.99), respectively]. Among mold infections, 12 patients suffered from invasive pulmonary aspergillosis, with Aspergillus fumigatus as the predominant pathogen (41.7 %). One case of brain scedosporiosis was identified. Overall, azoles and echinocandins resistance was uncommon. CONCLUSIONS: Candida non-albicans species are the most frequent cause of candidemia in ICU patients. Mold infections are associated with a high mortality rate. This study confirms the importance of the epidemiological surveillance on IFIs in the ICU setting for documenting species distribution and antimicrobial susceptibility patterns to guide therapeutic choices.

Sequence based typing of Legionella pneumophila sg 1 isolated in nosocomial acquired infections in Apulia, Southern Italy.

OBJECTIVE: The present report aims to molecularly characterize seven clinical L. pneumophila (L. pn.) sg 1 isolated from nosocomial acquired infections in Apulia region, using the European Working Group on Legionella Infections (EWGLI), sequence-based typing (SBT) and amplified fragment length polymorphism (AFLP) protocols and to compare the identified sequence types (STs) with those available in the EWGLI database. METHODS: In the period, January 2000-December 2012, 151 is cases (136 of community and 15 of nosocomial origin) of Legionnaires' disease were notified to the Regional Center for Epidemiology. With regard to nosocomial cases, 8 were confirmed by the isolation of Legionella spp. from respiratory secretions. These clinical isolates were characterized by amplified fragment length polymorphism (AFLP) and sequence-based typing (SBT), using the EWGLI standardized protocol. RESULTS: The clinical isolates belong to ST42, ST23 and ST1. The AFLP confirms the SBT results. Comparing the STs herein detected with those already in the EWGLI SBT database, the 3 STs are frequent in other European countries. CONCLUSIONS: The molecular analysis demonstrates that the 3 STs are the most frequent in Italy and in Europe, supporting the hypothesis that some specific L. pn. sg 1 clones have gained widespread dissemination probably due to a common ecological niche. Further researches are required to investigate the potential changing incidence of STs and the fitness of emerging strains or clonal groups in environmental strains.

Antifungal susceptibility testing of a 10-year collection of Candida spp. isolated from patients with candidemia.

Nosocomial yeast infections have increased significantly worldwide and especially in surgical and intensive care unit (ICU) patients. Although Candida species have various degrees of susceptibility to frequently used drugs, antifungal resistance is rare. A ten-year retrospective surveillance of candidemia was carried out in a University Hospital of Southern Italy. The aim of this study was the determination of Candida bloodstream infections (BSI) and central venous catheter (CVC)- related episodes, prevalence and in vitro susceptibility. 320 candidemia episodes were registered and 374 yeasts collected. Etest and Sensititre methods were used to test the isolates' susceptibility to amphotericin B, anidulafungin, caspofungin, fluconazole, itraconazole, posaconazole and voriconazole. The results were compared with those of CLSI reference broth microdilution method. Most yeasts were susceptible to all antifungal drugs, with the exception of C. Glabrata susceptibility to triazoles and C. tropicalis to fluconazole and voriconazole. As expected, C. parapsilosis isolates were generally associated with higher echinocandin minimum inhibitory concentrations (miCs) than the other Candida species. This study confirms the different antifungal susceptibility patterns among species, and underlines the need to perform antifungal susceptibility testing of clinically relevant yeasts.

Retrospective analysis of microorganisms isolated from cystic fibrosis patients in Southern Italy, 2002-2010.

OBJECTIVE: This study aim was to determine the prevalence of microorganisms in the respiratory tract of patients with cystic fibrosis (CF) admitted to the CF Reference Centre in Southern Italy between 2002-2010. METHODS: Microbiology assessment of samples (sputum and tracheal aspirates) collected from patients with pulmonary exacerbation admitted to hospital was carried out. All patients were registered in a database and clinical and microbiological data were retrospectively analysed. RESULTS: Overall, 188 patients were included and a total of 1217 samples were analysed. The most common microorganisms were Staphylococcus aureus (78.7% of the patients) and Pseudomonas aeruginosa (58%), followed by Candida albicans (19.1%), Haemophilus influenzae (13.3%) and Aspergillus fumigatus (9.6%). CONCLUSION: Compared to similar studies performed in other European countries, our microbiological data, especially the low occurrence of filamentous fungi, suggest a specific local epidemiology, probably related to some uncommon CFTR mutations, which are specific to Southern Italy.