Diffusion and transmission of carbapenem-resistant Klebsiella pneumoniae in the medical and surgical wards of a university hospital in Milan, Italy

Summary: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is emerging as a public health problem worldwide. In Italy, a remarkable increase in CRKP cases has been reported since 2010. In this study, CRKP diffusion, distribution and in-hospital transmission trends were evaluated in a university hospital in Milan, Italy, from January 2012 to December 2013. Isolates from 63 newly detected CRKP-positive patients were genotyped, and possible transmission was determined by combining the molecular results with data concerning the patients' admission and in-hospital transfers. Most of the cases (90.4%) were from general medical and surgery wards, and the remaining 9.6% were from the intensive care unit. Fifteen of the 46 hospital-associated cases (32.6%) were attributable to in-hospital transmission. After the introduction of targeted and hospital-wide control measures, the transmission index significantly decreased from 0.65 to 0.13 (p = 0.01). There was also a decrease in the overall nosocomial case incidence, from 0.37 to 0.17 per 1000 person-days (p = 0.07).Our findings indicate that the spread of CRKP in Northern Italy hospitals may go far beyond high-risk settings (i.e., intensive care units) and that strict surveillance should be extended to general areas of care. Keywords: Multidrug-resistant agents, Carbapenem-resistant Klebsiella pneumoniae, Cross-transmission, Infections control measures, Active surveillance, Active screenin

Detection of ST1702 Escherichia coli blaNDM-5 and blaCMY-42 genes positive isolates from a Northern Italian hospital

We describe two multi drug-resistant (MDR) carbapenemase-producing Escherichia coli clinical isolates from an acute hospital in Milan. Both strains, isolated from a surgical wound sample and a surveillance rectal swab respectively, were positive for a blaNDM-type gene by Xpert Carba-R test. The whole-genome sequence characterization disclosed several resistance determinants: blaNDM-5, blaCMY-42, blaTEM-198, rmtB, mphA. The two isolates belonged to phylogenetic group A, sequence type (ST) 1702 and serotype O89:H9. PCR-based replicon typing and conjugation assay demonstrated an IncI1 plasmid localization for both blaNDM-5 and blaCMY-42 genes. This is the first report of a ST1702 NDM-5 and CMY-42- producing E. coli clone in Italy

Influenza A/H1N1/2009 virus - experience of the clinical microbiology laboratory of the "L. Sacco" University Hospital in Milan

In the spring of 2009, a new variant of influenza A/H1N1 virus that had never been isolated before, was identified. From April 27 to December 31, 2009 the respiratory samples of 974 patients, obtained from suspected cases of pandemic influenza A virus infection, were analyzed at the Clinical Microbiology Laboratory of the "L. Sacco" University Hospital in Milan. The diagnosis of influenza A/H1N1 infection was performed initially through the use of different molecular biological methods: Seeplex® RV12 ACE Detection (Seegene), NUCLISENS® EASYQ® INFLUENZA A/B (bioMérieux), Influenza A/B Q-PCR Alert (Nanogen) running in parallel with rRT-PCR (CDC) to confirm the positivity to the new influenza virus, then was used a single specific test, Fast set H1N1v (Arrow Diagnostics). Retrospective study of data showed that 293 (30.1%) patients were positive for the new strain of influenza A/H1N1 virus and 8 (0.8%) for influenza A other than H1N1 virus.The distribution of influenza A/H1N1 cases showed two peaks, one on July (62.9%) and the other one on October (36%), moreover we observed that 155 patients (53%) out of 293 positive for influenza A/H1N1 virus aged under 20 years old. The first positivity peak was found in travelers and the second one, occurred 2-3 months prior to the classic seasonal epidemic influenza, was attributed to autochthonous cases , by which the virus had spread worldwide. The highest proportion of cases were among subjects aged from 0 to 20 years and, over this age the positivity rate decreased proportionally with increasing age, in agreement with data reported in other countries

Presence of carbepenemase-producing Enterobacteriaceae in the River Lambro basin, Italy: might sediment represent an important resistance reservoir?

In the last years, the rapid spread in anthropized ecosystems of pathogens which are resistant to carbapenem antibiotics has raised great concern. In this study, KPC-producing Klebsiella pneumoniae was found in the River Lambro in June 2019, whereas KPC-producing Klebsiella oxytoca and Citrobacter braakii were identified in untreated wastewaters. Susceptibility profiles indicated resistance to imipenem, ertapenem and meropenem. Different carbapenamase genes (blaKPC, blaNDM, blaVIM, blaOXA-48) were also found in the River Lambro, although not associated to living bacteria. The presence of a wide set of carbapenemase genes and resistant pathogens show that river sediments could act as a reservoir of antibiotic resistance potentially threatening human health

Mingling of human and veterinary strains of Staphylococcus aureus : an emerging issue in health-care systems

Aim: Methicillin-resistant Staphylococcus aureus remains a leading cause of hospital and community infections. We report a retrospective molecular characterization of S. aureus strains from different settings: hospital workers and patients, and veterinarian surgeons and pets. Materials and Methods: Eighty-nine S. aureus isolates obtained from nasal swabs of 10 patients, 17 health-care workers (HCWs), 9 pets, and 53 veterinarians were genotypically characterized by means of repetitive extragenic palindromic polymerase chain reaction (Rep PCR) and whole-genome sequencing. Results: Thirteen different sequence types (STs) were detected: ST398, ST22, ST8, ST30, ST15, ST5, ST121, ST45, ST10, ST6, ST34, ST97, and ST1. Two new STs differing from ST22 and ST5 for a single multilocus sequence typing gene were also identified. Rep PCR documented a genetic relationship among isolates obtained from 5 veterinarians and 10 HCWs. Conclusion: The large diversity of S. aureus strains detected may reflect a larger epidemiology within the hospital and community, in which companion animals likely act as a reservoir. We identified the circulation of ST5, ST8, ST15, ST22, ST30, ST45, and ST121 both in the hospital and veterinarian environment. Starting from the idea of a unique setting where our population lives, we consider the relationship between community- and hospital-acquired S. aureus

Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020

We show the distribution of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three genomic nomenclature systems to all sequence data from the World Health Organization European Region available until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation, compare the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2

EPIDEMIOLOGICAL OBSERVATORY: spreading of ESBL and carbapenemase positive strains in the period between January 2007 - June 2012, at the Hospital - University Campus - Hospital “Luigi Sacco” in Milan

Infections caused by ESBL-producing Enterobacteriaceae and carbapenemases producing bacteria are a growing phenomenon which is one of the leading causes of death among elderly or immunosuppressed patients and is also associated with a higher cost of hospitalization. As worldwide, also in Italy a steady and alarming increase of these microorganisms is reported. With the present paper we present a brief review of the prevalence of ESBL-producing and carbapenemase strains isolated at the Hospital - University Campus - Hospital “Luigi Sacco” in Milan between January 2007 and June 2012. Samples ESBLs positive (Vitek2: bioMérieux, France) were subjected to phenotype confirmation by E-test method (bioMérieux, France). In addition 34 K. pneumoniae carbapenemases producing strains collected between 2011 and 2012, were firstly confirmed with an Hodge test and then tested with a NASBA EasyQ KPCv1.0 test (bioMérieux, France) able to detect the bla KPC gene. The data collected showed a high prevalence of ESBLs and carbapenemases producing strains. 1828 out of 15585 were positive for ESBL with the following distribution: 15.6% E. coli, 13.0% K. pneumoniae, 3.6% Enterobacter spp, 7.7% P. mirabilis and 6% P. aeruginosa. Out of 1828, 193 samples (10.5%) were confirmed as positive and respectively 89.4% were E. Coli, 80% were K. pneumoniae and 89.5% were P. mirabilis. The 3.6% of strains were positive for carbapenemase: 45.3% were A. baumannii and 41.8% were P. aeruginosa. K. pneumoniae strains carbapenemase positive were confirmed in 100% of cases by the Hodge test and in 97% of cases by molecular investigation

Rapid diagnosis of bacteric meningitis

Gram stain and bacterial antigen detection are economic and rapid tests for the identification of the bacteria in cerebrospinal fluid (CSF) for the diagnosis of meningitis. Even if culture is the gold standard of these diagnosis, it requires long time (growth time). The purpose of our study was to compare in the laboratory diagnosis of meningitis real time PCR (Eurospital, Italy). with standard methods. Samples were collected in patients referred to L. Sacco Universital Hospital (range of age: 16 to 70 years) from September 2008 to July 2009. 9 out of 130 CFS samples investigated were positive in PCR but they produced different results to the other methods used

New viral gastrointestinal agents associated with paediatrics illness

Objective Aim of our study was investigate the presence of enteric viruses like Norovirus, Bocavirus and Rotavirus in hospitalized children belong to Paediatrics Clinics of L. Sacco Hospital. Material and methods 150 faecal samples were investigated from January 2008- 2009, by PCR real time for Norovirus and Bocavirus; Rotavirus was detected by enzyme immunoassay. Results We obtain a positive result on total samples in percentage of 36%: Rotaviruses are estimated to cause more than 20% of gastroenteritis cases; Noroviruses 7.3% cases; Bocaviruses 6.6% cases. Rotaviruses infections occurred in children 1-4 years of age and for 2 cases at 7 and 13 years old. Illness typically happened in the cooler months from January to March even if there were few positive cases in September/October. Noroviruses and Bocaviruses infections occurred in children 1-2 years of age and their seasonality were respectively from September to December and from January to March for Bocaviruses. Conclusions The present results point out the importance to detect new viral gastrointestinal agents associated with paediatric illness

Norovirus circulation in pediatric patients

An eighteen-month study (2008-2009) was carried out on patients, aged on average 30 months, admitted with gastroenteritis to the Paediatric Unit of the L. Sacco Hospital in Milan, Italy. Faecal samples of 154 patients were investigated for Rotavirus, Norovirus,Adenovirus, Enterovirus and Bocavirus. A total of 25 norovirus positive samples were selected for nucleotide sequence analysis, that allowed identify GII.2, GII.3 and GII.4 2006 virus variants (06 a, 06 b)