Marina De Cesaris

Routine molecular identification of enterococci by gene-specific PCR and 16S ribosomal DNA sequencing.

ABSTRACT For 279 clinically isolated specimens identified by commercial kits as enterococci, genotypic identification was performed by two multiplex PCRs, one with ddlE. faecalis andddlE. faecium primers and another withvanC-1 and vanC-2/3 primers, and by 16S ribosomal DNA (rDNA) sequencing. For 253 strains, phenotypic and genotypic results were the same. Multiplex PCR allowed for the identification of 13 discordant results. Six strains were not enterococci and were identified by 16S rDNA sequencing. For 5 discordant and 10 concordant enterococcal strains, 16S rDNA sequencing was needed. Because many supplementary tests are frequently necessary for phenotypic identification, the molecular approach is a good alternative.

Group A Streptococcal Genotypes from Pediatric Throat Isolates in Rome, Italy

ABSTRACT In a study assessing genetic diversity, 114 group A streptococcus (GAS) isolates were recovered from pediatric pharyngitis patients in Rome, Italy. These isolates comprised 22 different M protein gene (emm) sequence types, 14 of which were associated with a distinct serum opacity factor/fibronectin binding protein gene (sof) sequence type. Isolates with the same emmgene sequence type generally shared a highly conserved chromosomal macrorestriction profile. In three instances, isolates with dissimilar macrorestriction profiles had identical emm types; in each of these cases multilocus sequence typing revealed that isolates with the same emm type were clones having the same allelic profiles. Ninety-eight percent of the pharyngeal isolates hademm types previously found to be highly associated withmga locus gene patterns commonly found in pharyngeal GAS isolates.

Erythromycin-Resistant Pharyngeal Isolates of Streptococcus pyogenes Recovered in Italy

ABSTRACT Three classes of macrolide resistance phenotypes and three different erythromycin resistance determinants were found among 127 erythromycin-resistant group A streptococcal (GAS) isolates recovered from 355 (35.8%) pediatric pharyngitis patients in Rome, Italy. According to emm and sof sequence typing results, erythromycin-resistant isolates comprised 11 different clonal types. Remarkably, 126 of the 127 macrolide-resistant isolates were serum opacity factor (sof) gene positive. These data suggest a strong association between macrolide resistance and the presence of sof among GAS isolates recovered from Italian pediatric pharyngitis patients.

Unusual microorganisms and antimicrobial resistances in a group of Syrian migrants: Sentinel surveillance data from an asylum seekers centre in Italy.

BACKGROUND Three years of civil war in Syria have caused death and increase of communicable diseases. The suffering population has been forced to migrate creating a fertile condition for epidemic spread of infection within the refugee camps. METHODS Forty-eight Syrian migrants, upon their arrival in Italy, were accommodated at the asylum seekers centre of Castelnuovo di Porto. They received a physical examination and were subjected to microbiological surveillance by blood, rectal, pharyngeal and nasal swabs collection and delivering to the Clinical Pathology and Microbiology Laboratory of the University Campus Bio-Medico of Rome. RESULTS All refugees resulted negative for HBV, HCV and HIV infections. In swabs a large number of unusual gram-negative bacteria species were isolated, such as Pseudomonas putida, Pseudomonas monteilii, Pseudomonas fulva, Pseudomonas moselii, Aeromonas veronii, Aeromonas caviae, Aeromonas hydrophila, Acinteobacter guilloviae, Acinteobacter lowffii; Acinetobacter johnsonii; Acinteobacter tjernbergae; Pantoea agglomerans; Pantoea calida. Among isolates, strains resistant to carbapenems, ESBL producers and methicillin resistant were found. CONCLUSIONS The microbiological surveillance performed represents a useful action to understand refugees health status and to trace unusual microorganisms movement even carriers of antimicrobial resistance during migrants traveling.

Procalcitonin, MR-Proadrenomedullin, and Cytokines Measurement in Sepsis Diagnosis: Advantages from Test Combination

Background. Elevated cytokines levels correlate with sepsis severity and mortality but their role in the diagnosis is controversial, whereas Procalcitonin (PCT) has been largely used. Recently, the mid-regional proadrenomedullin (MR-proADM) has been combined with PCT for diagnosis optimization. In this study the combined measurement of PCT, MR-proADM, and cytokines in patients with sepsis was evaluated. Methods. One hundred and four septic patients and 101 controls were enrolled. Receiver operating characteristic (ROC) analysis and multiple logistic regression were used to evaluate applicant markers for sepsis diagnosis. Markers with best Odds Ratio (OR) were combined, and the posttest probability and a composite score were computed. Results. Based upon ROC curves analysis, PCT, MR-proADM, IL-6, IL-10, TNF-α, and MCP-1 were considered applicant for sepsis diagnosis. Among these PCT, MR-proADM , IL-6, and TNF-α showed the best OR. A better posttest probability was found with the combination of PCT with MR-proADM and PCT with IL-6 or TNF-α compared to the single marker. A composite score of PCT, MR-proADM, and TNF-α showed the best ROC curve in the early diagnosis of sepsis. Conclusion. The combination of PCT with other markers should expedite diagnosis and treatment of sepsis optimizing clinical management.

Role of Neutrophil Gelatinase-Associated Lipocalin in the Diagnosis and Early Treatment of Acute Kidney Injury in a Case Series of Patients with Acute Decompensated Heart Failure: A Case Series

Patients with acute decompensated heart failure (ADHF) frequently develop worsening in renal function until Acute Kidney Injury (AKI). The use of kidney injury biomarkers could be useful in the early diagnosis of AKI. In the present study, the role of the neutrophil gelatinase-associated lipocalin (NGAL), compared to the standard creatinine, in ADHF patients, was analyzed to evaluate if an early treatment could affect the outcome. A case series of 24 ADHF patients was enrolled and patients randomly divided in two groups (Group A and Group B). In Group A, NGAL, creatinine, and eGFR were measured, while in Group B, creatinine and eGFR alone were measured. NGAL was measured by turbidimetric immunoassay and creatinine using an enzymatic spectrophotometric method. In presence of AKI, creatinine increase and eGFR decrease were significantly lower in Group A than in Group B, whereas in absence of AKI the difference between the two groups was not significant. Hospitalization stay was significantly lower in Group A (receiving early treatment based on NGAL) than in Group B. In ADHF patients, plasma NGAL in combination with creatinine was superior to the standard creatinine in the diagnosis and early treatment of AKI with a better outcome and a decreased hospital stay.

Laboratory Automation and Intra-Laboratory Turnaround Time Experience at the University Hospital Campus Bio-Medico of Rome

Intra-laboratory turnaround time (TAT) is a key indicator of laboratory performance. Improving TAT is a complex task requiring staff education, equipment acquisition, and adequate TAT monitoring. The aim of the present study was to evaluate the intra-laboratory TAT after laboratory automation implementation (June 2013–June 2014) and to compare it to that in the preautomation period (July 2012–May 2013). Intra-laboratory TAT was evaluated both as the mean TAT registered and the percentage of outlier (OP) exams. The mean TAT was 36, 38, and 34 min during the study periods, respectively. These values respected the goal TAT established at 45 min. The OP, calculated at 45 min as well as at 60 min, decreased from 26 to 21 and from 11 to 5, respectively. From a focused analysis on blood count cell, troponin I, and prothrombin (PT) test, TAT improvement was more evident for tests requiring longer preanalytical process. The follow-up of TAT from June 2013 to June 2014 revealed the reduction of the mean TAT as well as of the OP exams after automation implementation and that automation more strongly affects the test in the preanalytical phase including centrifugation of the sample, such as troponin I and PT.

Multi-drug resistant Klebsiella pneumoniae strains circulating in hospital setting: whole-genome sequencing and Bayesian phylogenetic analysis for outbreak investigations

Carbapenems resistant Enterobacteriaceae infections are increasing worldwide representing an emerging public health problem. The application of phylogenetic and phylodynamic analyses to bacterial whole genome sequencing (WGS) data have become essential in the epidemiological surveillance of multi-drug resistant nosocomial pathogens. Between January 2012 and February 2013, twenty-one multi-drug resistant K. pneumoniae strains, were collected from patients hospitalized among different wards of the University Hospital Campus Bio-Medico. Epidemiological contact tracing of patients and Bayesian phylogenetic analysis of bacterial WGS data were used to investigate the evolution and spatial dispersion of K. pneumoniae in support of hospital infection control. The epidemic curve of incident K. pneumoniae cases showed a bimodal distribution of cases with two peaks separated by 46 days between November 2012 and January 2013. The time-scaled phylogeny suggested that K. pneumoniae strains isolated during the study period may have been introduced into the hospital setting as early as 2007. Moreover, the phylogeny showed two different epidemic introductions in 2008 and 2009. Bayesian genomic epidemiology is a powerful tool that promises to improve the surveillance and control of multi-drug resistant pathogens in an effort to develop effective infection prevention in healthcare settings or constant strains reintroduction.

Susceptibility to measles in migrant population: implication for policy makers

Background Despite a large measles outbreak is taking place in WHO European region, currently no data are available on measles immunization coverage in the asylum seeker and migrants hosted in this area. Methods Two hundred and fifty-six migrants upon their arrival in Italy on March, April and May 2016 were screened for measles virus IgG antibodies by chemiluminescence immunoassay (Liaison XL analyzer, Diasorin, Italy). The virus susceptibility in this cohort, the differences between the official country reported and the observed measles immunization coverage and the impact of current measles outbreak on the asylum seekers hosted in the largest Asylum Seeker centres of Italy, were evaluated. Results The prevalence of subjects with positive result for measles IgG antibodies ranged between 79.9% and 100%. In Senegal, Mali, Nigeria, Pakistan and Bangladesh, the measles IgG seroprevalence observed was greater than the vaccinal coverage reported by WHO after I dose of vaccine. Based on data regarding the II dose coverage, the ASs population presented a seroprevalence greater to that expected. Conclusion On the basis of the results obtained, extraordinary screening and vaccination campaigns in the migrant population, especially in the course of large outbreaks, could represent a resource to reach an adequate measles immunization coverage and to control this infectious disease.