Real-life efficacy and safety of Ustekinumab as second- or third-line therapy in Crohn's disease: results from a large Italian cohort study.

OBJECTIVE: Ustekinumab (UST) is an anti-IL12/23 antibody for the treatment of Crohn's Disease (CD). The aim of this study was to compare the efficacy and safety of UST in a large population-based cohort of CD patients who failed previous treatment with other biologics. PATIENTS AND METHODS: 194 CD patients (108 males and 86 females, mean age 48 years (range 38-58 years) were retrospectively reviewed. 147 patients were already treated with anti-TNFα (75.8%), and 47 (24.2%) patients were already treated with anti-TNFα and vedolizumab. Concomitant treatment with steroids was present in 177 (91.2%) patients. RESULTS: At week 12, clinical remission was achieved in 146 (75.2%) patients. After a mean follow-up of 6 months, clinical remission was maintained in 135 (69.6%) patients; at that time, mucosal healing was assessed in 62 (31.9%) patients, and it was achieved in 33 (53.2) patients. Three (1.5%) patients were submitted to surgery. Steroid-free remission was achieved in 115 (59.3%) patients. Both serum C-Reactive Protein and Fecal Calprotectin (FC) levels were significantly reduced with respect to baseline levels during follow-up. A logistic regression, UST therapy as third-line therapy (after both anti-TNFα and vedolizumab), FC >200 µg/g, and HBI ≥8 were significantly associated with lack of remission. Adverse events occurred in 5 (2.6%) patients, and four of them required suspension of treatment. CONCLUSIONS: UST seemed to be really effective and safe in CD patients unresponsive to other biologic treatments, especially when used as second-line treatment.

The EBV-DNA Can be Used as a Diagnostic and Follow-up Parameter of the Rhinopharyngeal Tumors in the Non-Endemic Population of the Western Sicily.

To evaluate whether EBV-DNA can be used as a diagnostic and follow-up parameter for nasopharyngeal tumors in a non-endemic population. The study was carried out in a university hospital. A retrospective study was conducted on 40 paraffin samples of histological preparations. EB-DNA was detected by real-time PCR technique. A prospective study was also conducted on a group of 30 patients who underwent nasopharyngeal biopsy for suspected nasopharyngeal carcinoma (NPC) by comparing EBV-DNA concentrations between the histological specimen and the serum. Quantification of genomic copies of EBV-DNA in serum and detection of anti-EBV antibodies was performed. In both groups the presence of high viral load of EBV-DNA was found in nonkeratinizing squamous cell carcinomas, in three cases of lymphepitomyoma and in 4 out of 6 cases of non-differentiated non-carcinoma lymph node metastases. squamous keratinizing cells. In all cases of NPC, an antibody pattern typical of reactivations (IgGVCA+, IgG-EA+, IgG-EBNA+) and IgA-EA-D, frequently positive in cases of NPC, has been highlighted. A good correlation between the high EBV-DNA charges and the histological diagnosis was highlighted. Our study also found that the assessment of viral EBV load can also be considered in the prognostic evaluation and in the follow-up of patients with NPC.

First report of Salmonella 1,4,[5],12:i:- in free-ranging striped dolphins (Stenella coeruleoalba), Italy.

Between 2015 and the beginning of 2018 (January-March), 30 cetaceans were found stranded along the Ligurian Sea coast of Italy. Necropsies were performed in 22 cases and infectious diseases resulted the most common cause of death. Three striped dolphins, showed a severe coinfection involving the monophasic variant of Salmonella Typhimurium (Salmonella 1,4,[5],12:i:-). The isolates were characterized based on antimicrobial resistance, Multiple-Locus Variable-number tandem-repeat Analysis (MLVA) and whole-genome sequencing (WGS). All isolates demonstrated the same multidrug resistant genotype (ASSuT isolates), showed three different MLVA profiles, two of which closely related, and were identified as Sequence Type 34. Moreover, Single nucleotide polymorphisms (SNP) analysis confirmed strong correlations between two out of the three isolates. To our knowledge, S. 1,4,[5],12:i:-, one of the most common serovars in cases of human infection and food sources worldwide, has not previously been described in marine mammals, and reports of Salmonella-associated disease in free-ranging cetaceans are rare. These results highlight the role of cetaceans as sentinel species for zoonotic and terrestrial pathogens in the marine environment, suggest a potential risk for cetaceans and public health along the North Western Italian coastline and indicate cetaceans as a novel potential reservoir for one of the most widespread Salmonella serovars.

Notch-1 signaling activation sustains overexpression of interleukin 33 in the epithelium of nasal polyps.

BACKGROUND: Alterations in the nasal epithelial barrier homeostasis and increased interleukin 33 (IL-33) expression contribute to the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). AIMS: As Notch-1 signaling is crucial in repair processes of mucosa, the current study assessed Notch-1/Jagged-1 signaling and IL-33 in the epithelium of nasal polyps biopsies from allergic (A-CRSwNP; n = 9) and not allergic (NA-CRSwNP; n = 9) subjects by immunohistochemistry. We also assessed, in a model of nasal epithelial cells, the effects of stimulation of Notch-1 with Jagged-1 on the expression of IL-33 (by flow cytometry, immunofluorescence, and immunocytochemistry), Jagged-1 (by flow cytometry), and p-CREB transcription factor (by western blot analysis). RESULTS: Ex vivo (a) in normal epithelium, the expression of Notch-1 and IL-33 were higher in NA-CRSwNP than in A-CRSwNP; (b) in metaplastic epithelium, the expression of Notch-1, Jagged-1, and IL-33 were higher in NA-CRSwNP than in A-CRSwNP; (c) in hyperplastic epithelium, the expression of Notch-1, Jagged-1, and IL-33 were higher in A-CRSwNP than in NA-CRSwNP; and (d) in basal epithelial cells, no differences were observed in the expression of Jagged-1, IL-33, and Notch-1. The expression of Notch-1 significantly correlated with the expression of IL-33. In vitro, stimulation of Notch-1 with Jagged-1 induced the expression of (a) Jagged-1; (b) IL-33; and (c) p-CREB transcription factor. The inhibitor of Notch-1, DAPT, reduced all the effects of Jagged-1 on nasal epithelial cells. CONCLUSIONS: The data herein provided support, for the first time, a putative role of Notch-1/Jagged-1 signaling in the overexpression of IL-33 in the epithelium of nasal polyps from patients with CRSwNP.

Behavior of Escherichia coli O157:H7 during the manufacture and ripening of Fontina Protected Designation of Origin cheese.

This study was conducted to describe the cheese-making procedure of Fontina Protected Designation of Origin (PDO) cheese and to evaluate the behavior of Escherichia coli O157:H7 during cheese manufacture and ripening. The study was divided into 2 phases: the production of Fontina PDO cheese was monitored at 3 different dairies in the Aosta Valley and an E. coli O157 challenge was conducted at a fourth dairy. The dairies employ different commercial starter cultures for cheese making. The growth of lactic acid bacilli (LAB) and the decrease in pH were slower in the first hours and the LAB concentrations were overall higher in dairy A than in the other 2 dairies. The pH remained substantially unchanged during ripening (range 5.2 to 5.4) in all dairies. Water activity remained constant at around 0.98 until d 21, when it decreased to around 0.97 until d 80 in dairies A and B and 0.95 in dairy E. Whole raw cow milk was used for making Fontina cheese according to the standard procedure. For the experimental production, the milk was inoculated with E. coli O157:H7 at a concentration of approximately 5 log10 cfu/mL and commercial starter cultures were used according to the Fontina PDO regulation. An increase of 2.0 log10 cfu/g in E. coli O157:H7 was observed during the first 9.5 h of cheese making, followed by a decrease at 46 h when pH decreased to 5.4 in all trials. Fresh cheeses were salted and held at 10°C for ripening for 80 d. Water activity was decreased to 0.952 at the end of the ripening stage. The LAB concentrations declined gradually; this trend was more marked for the lactobacilli than either the thermophilic or the mesophilic lactococci. The increase in LAB count and the decrease in pH in the first hours did not seem to affect E. coli O157 growth. Ripening was found to inhibit pathogen survival, however, as seen in the reduction of 3 log10 from the maximum concentration measured during the earlier stages of production.

Short communication: Characterization of Staphylococcus aureus isolated along the raw milk cheese production process in artisan dairies in Italy.

Staphylococcus aureus is a common cause of food-borne intoxications. Several staphylococcal food poisoning outbreaks have been linked to consumption of raw milk cheeses and artisanal cheese production. However, information on Staph. aureus isolated from artisanal raw milk cheeses and small-scale dairy production environments is very limited. Therefore, we aimed to characterize Staph. aureus isolated along the artisanal raw milk production chain by determining (1) the population structure, and (2) the presence/absence of enterotoxin genes, mecA/C, and pvl. We collected 276 samples from different production stages (raw milk, whey, curd, brine, drying worktops, and cheese) at 36 artisan dairies in Italy. A total of 102 samples from 25 dairies tested positive for Staph. aureus, with 80% positive samples among the tested artisan cheeses. All isolates were further characterized by spa typing and PCR screening for staphylococcal enterotoxin genes, the mecA/mecC genes characteristic for methicillin-resistant Staph. aureus, and the pvl gene encoding Panton-Valentine leukocidin. The 102 isolates represented 15 different spa types and were assigned to 32 different Staph. aureus strains. The spa type most frequently detected was t2953 (30%), which is associated with genotype B strains causing high within-herd levels of bovine mastitis. In addition, 3 novel spa types (t13269, t13277, and t13278) were identified. Although none of the strains harbored mecA/mecC or pvl, 55% of the isolates exhibited at least one enterotoxin gene. Many strains were present in samples from multiple dairies from different regions and years, highlighting the spread of Staph. aureus in small-scale cheese production plants. Our findings demonstrate that enterotoxigenic Staph. aureus and in particular t2953 (genotype B) isolates commonly occur in artisanal dairies and raw milk cheeses in Italy. It is particularly alarming that 80% of the artisan cheeses sampled in our study were positive for Staph. aureus. These findings stress the need for effective measures preventing staphylococcal food poisoning by limiting Staph. aureus growth and enterotoxin formation along the production chain and in the final product.

Clarithromycin in the Management of Chronic Rhinosinusitis: Preliminary Results of a Possible Its New Use.

The aim of this study is to evaluate the efficacy and safety of prolonged therapy with low-dose clarithromycin in patients with chronic rhinosinusitis with polyps (CRSwP) after endoscopic sinus surgery (ESS). A total of 10 patients with CRSwP were identified and subjected to bilateral ESS. In post-operative patients they were treated with nasal wash with saline solution and steroid sprays (beclomethasone). During follow-up, after 30-40 days after the operation (M = 35.4 SD = +4.33), patients reported a worsening of symptoms with onset of nasal obstruction; reduction/loss of smell; headache; onset of viscous secretions and therefore all patients continued therapy with saline nasal irrigation, topical steroid therapy and started macrolide (clarithromycin 500 mg/pill: 1 pill/day for 3 days a week for 1 month). 22-item SinoNasal Outcome Test (SNOT-22) and a score to the endoscopic evaluation (endoscopic appearance score, EAS) before and after treatment were performed to evaluate efficacy of treatment. The results of the SNOT-22 and EAS showed statistically significant improvements (p < 0.05) for some parameters such as: the need to blow nose, sneezing, hyposmia, viscous mucous secretions about the SNOT-22 and reduction of secretions and edema of the nasal mucosa about the EAS. The preliminary results of our study show that the low-dose clarithromycin for a period of 1 month can improve patient complaints with CRSwP not only through the antibacterial properties but also for the immunomodulatory characteristics.

Vitamin a decreases after a maximal incremental stress test in non-professional male runners with low aerobic performance.

The data on the effects of aerobic training on plasma antioxidant vitamins are conflicting. Additionally, most studies focus on the oxidative profiles of professional athletes, but limited information is available for amateur athlete populations. The aim of this study was to evaluate the effects of high-intensity exercise on antioxidant vitamins in non-professional runners with varying levels of aerobic power. Eighty-one male runners underwent an incremental test to exhaustion. The study population was then divided into the following tertiles according to VO2max: Group L (LowVO2max, less than 44.2 mLkg-1min-1), Group M (MediumVO2max, 44.2-49.7 mLkg-1min-1) and Group H (HighVO2max, >49.7). Comparative analyses were performed between Groups L and H. The total antioxidant capacity (TAC), Vitamin (Vit) E, Vitamin A, ß-carotene, lycopene and thiobarbituric acid-reactive substances (TBARS) were determined before and 60 min after exercise testing. After the stress test, Vit A decreased and TBARS increased in Group L, whereas no changes in the vitamin concentrations, TAC induction and TBARS reduction were observed in group H. In individuals with low VO2max, an incremental test determined lipid-peroxidation and Vitamin A consumption, whereas H Group increases TAC that buffer TBARS production.

Increased left atrial size in obese children and its association with insulin resistance: a pilot study.

Subclinical cardiac abnormalities represent predisposing factors for cardiovascular disease (CVD) in obese subjects. The aim of this study was to evaluate early cardiac abnormalities in obese youth and the potential association with insulin resistance (IR). Thirty obese (12 males (M)/18 females (F); age = 11.5 ± 2.4 years; body mass index (BMI)-standard deviation score (SDS) = +2.1 ± 0.5) and 15 normal weight (10 M/5 F; age = 12.8 ± 3.1 years; BMI-SDS = +0.3 ± 0.9) children and adolescents underwent Doppler two-dimensional echocardiographic assessments of left atrial (LA) and ventricular (LV) geometry and LV diastolic function (peak early [E] and late waves, E wave deceleration time, myocardial flow velocities). Homeostasis model assessment of IR (HOMA-IR) was used as an IR index. LA size was increased in obese children, as indicated by higher LA diameter (4.9 ± 0.5 vs 4.1 ± 0.4 cm, p < 0.001), area (14.3 ± 2.5 vs 10.7 ± 2.0 cm(2), p < 0.001), and volume (33.8 ± 10.6 vs 23.7 ± 6.4 ml, p = 0.003). LV mass was also increased in obese children (87.0 ± 16.6 vs 68.8 ± 13.2 g, p = 0.003), who also showed subtle diastolic dysfunctions, as indicated by higher values of E (97.1 ± 14.3 vs 86.2 ± 11.9 cm/s, p = 0.02). All the above parameters were significantly associated with BMI-SDS (p < 0.05). In addition, HOMA-IR was independently associated with LA diameter, area, and volume (ß = 0.314, p = 0.040; ß = 0.415, p = 0.008; ß = 0.535, p = 0.001). CONCLUSION: Obese children feature increased LA size, which emerged to be mainly correlated to, and possibly driven by IR, suggesting an increased CVD risk. WHAT IS KNOWN: Left atrial and ventricular alterations have been reported in obese adults, and they represent predisposing factors for cardiovascular disease. There is some evidence suggesting that obese children show increased left ventricular mass and also increased atrial size, although with conflicting results. WHAT IS NEW: Obese normotensive children showed a moderately increased atrial size, subtle alterations in left cardiac diastolic function, and ventricular mass. An association between insulin resistance and left cardiac changes was found, although its mechanism remains to be determined.

Bipolar Quantum Molecular Resonance versus Blunt Dissection tonsillectomy.

OBJECTIVES: This study compared a quantum molecular resonance tonsillectomy (QMRT) to a standard blunt dissection tonsillectomy (BDT) for effectiveness and safety. METHODOLOGY: From January 2011 to September 2012, we recruited 80 children (ages 3 to 16 y) with paediatric obstructive sleep apnoea syndrome and/or recurrent tonsillitis. Patients were randomly assigned to receive QMRT (N = 40) or BDT (N = 40). The operating time and blood loss during surgery were evaluated. During the first postoperative week, the patients' parents completed a questionnaire to evaluate bleeding, ear and neck pain, nausea, vomiting, interrupted sleep, oral liquid intake or discomfort in fluid assumption, and analgesic consumption. RESULTS: The average tonsillectomy duration was significantly shorter in the QMRT group (22.07 min ± 9.05) than in the BDT group (35.12 min ± 13.32; p < 0.000005). The average blood loss during tonsillectomy was significantly lower for the QMRT group (5.62 ml ± 7.44) than for the BDT group (43 ml ± 33.20; p < 000000001). However, the BDT group reported significantly lower pain scores than the QMRT group on days 2 (p < 0.05), 5 (p < 0.05), and 6 (p < 0.05); on other days, the groups were not significantly different. The BDT group reported two early and one late bleeding episodes; the QMRT group recorded only two late bleeding episodes. CONCLUSIONS: QMRT significantly reduced the operating time and intra-operative blood loss. No significant differences were found between the two techniques in postoperative pain or bleeding.

Methicillin resistance in Staphylococcus aureus strains isolated from food and wild animal carcasses in Italy.

Following the detection of methicillin-resistant Staphylococcus aureus (MRSA) ST398 in food-producing animals, both livestock and wildlife, and derived products, are considered potential sources of MRSA in humans. There is a paucity of data on MRSA in foods in Italy, and the data regarding wild animals are particularly scarce. A total of 2162 food samples collected during official monitoring activities in 2008 were analyzed for the detection of S. aureus. Also, samples from 1365 wild animals collected by the National Reference Center for Wild Animal Diseases in 2003-2009 were subjected to anatomopathological examination. S. aureus isolates were processed for phenotypic and molecular methicillin resistance determinations. S. aureus was found in 2.0% of wild animal carcasses and in 3.2% of wild boar lymph nodes: none showed methicillin resistance. The prevalence of S. aureus in food was 17.1%. Two MRSA strains, both from bulk tank milk (prevalence 0.77%) were isolated: the strains were resistant to tetracycline, had spa-type t899, and were negative for the Panton-Valentine leukocidin gene. The low prevalence of MRSA suggests that the risk of transmission to humans via food is limited. However, attention should be paid to the cattle food chain, which may be a potential route of transmission of LA-MRSA.

The immunohistochemical peptidergic expression of leptin is associated with recurrence of malignancy in laryngeal squamous cell carcinoma.

Leptin is a peptide that plays a key role in the control of satiety, energy expenditure, food intake and various reproductive processes. In the last years, the expression of leptin had been found in malignant cells of various origins. The aim of this study is to evaluate leptin expression in human laryngeal squamous cell carcinoma (SCC) and to investigate its possible role in predicting prognosis. Leptin expression was determined by immunohistochemistry in pathological and healthy tissue specimens from 24 patients with laryngeal SCC. Specimens were stained with an anti-leptin antibody. All measurements were performed using a computer-based image analysis system and scale of staining intensity was determined. All tumoural specimens showed significant immunoreactivity for leptin compared to healthy tissues (p ≤ 0.05), but showed different immunoreactivity that was related to clinicopathological features. High leptin expression was not significantly related with TNM, histological grading (HG) or advanced (III and IV) clinical stage (p > 0.05). Recurrence of malignancy was found to be significantly related with high expression of leptin by Spearman's rank correlation test (r = 0.59; p = 0.002), Fisher's test (p = 0.017) and Kaplan- Meier product-limit estimate (Log-rank test, p ≤ 0.05). In particular, multivariate logistic regression analysis showed that recurrences were significantly related with nodal involvement, HG and leptin expression (p ≤ 0.05). These preliminary results suggest that leptin may be a valuable parameter for predicting prognosis in laryngeal SCC.

Glioblastoma multiforme and hepatitis B: do the right thing(s).

OBJECTIVE: Hepatitis B virus (HBV) reactivation is a well-known complication related to immunosuppression. Clinical manifestations of HBV relapse range from self-limiting anicteric hepatitis to acute hepatic failure. Temozolomide (TMZ) is an alkylating agent used for the treatment of glioblastoma multiforme (GBM), the most common and deadliest of malignant primary brain tumors. CASE REPORT: We report the case of a 52-year old man with a history of serological positivity for hepatitis B surface antigen (HBsAg) who was diagnosed with GBM. Since the tumor was multifocal and thus inoperable, the patient received radiotherapy with concomitant TMZ and corticosteroids, without a prophylactic therapy for HBV infection. Acute hepatitis developed five months later the beginning of anticancer therapy. We started antiviral entecavir, which led to a decrease of HBV-DNA titer to 20 IU/ml, allowing the prosecution of the TMZ therapy. CONCLUSIONS: Up to now only four other cases of HBV relapse during TMZ therapy have been reported in literature. These cases underline the need of HBV screening and antiviral prophylaxis before starting TMZ administration.

Reproducibility study for the detection of Staphylococcal enterotoxins in dairy products between official Italian national laboratories.

Staphylococcal food poisoning is a common foodborne disease caused by the ingestion of staphylococcal enterotoxins (SEs) produced mainly by enterotoxigenic strains of Staphylococcus aureus. To date, 21 SEs and/or enterotoxin-like types have been identified, several of which represent a potential hazard for consumers. To protect consumer health and to reduce the amount of SE-contaminated food entering the market, European Union legislation regulating food safety requires testing for SEs. The Italian National Reference Laboratory organized a ring trial to test technical and analytical proficiency in the national network of official food laboratories. Twenty-four laboratories took part, and each received and analyzed 24 blind dairy samples. Reproducibility of the results from the laboratories was assessed by the Cohen k index, and accuracy (sensitivity and specificity) was evaluated according to the International Organization for Standardization definition (ISO 16140:2003). Trial results revealed partially satisfactory agreement: 254 of 276 possible paired participants (92%) reached a k value >0.60, which is conventionally recognized as satisfactory. Accuracy was deemed satisfactory; 100% sensitivity and 100% specificity were achieved by 22 and 18 of the 24 laboratories, respectively.

Validation according to ISO 16140:2003 of a commercial real-time PCR-based method for detecting Campylobacter jejuni, C. coli, and C. lari in foods.

Campylobacteriosis was the most frequently reported zoonosis in the European Union (EU) in 2010, with Campylobacter jejuni, Campylobacter coli, and Campylobacter lari as the most frequently reported species in foodborne outbreaks (FBOs). Relatively sensitive to environmental factors, these species may be present in low numbers. In line with EU policy for food control and FBO detection and in view of the need to reduce response time, we validated an alternative molecular method according to ISO 16140:2003 which establishes the general principle and technical protocol for the validation of alternative methods in the microbiological analysis of food. We used a qualitative real-time PCR commercial kit for the detection of C. jejuni, C. coli, and C. lari in two food categories "fruit and vegetable-based products" and "dairy products". The validation protocol comprises two phases: the first is a method comparison study of the alternative method against the reference method, and the second is an interlaboratory study of each of the two methods. In the first step, ISO 16140:2003 validation examines the following parameters: limit of detection (LOD); relative accuracy, relative specificity and sensitivity; relative detection level (RDL); and inclusivity and exclusivity. Except for LOD, inclusivity and exclusivity, the other steps were performed against the reference method (ISO 10272:2006). The LOD of the real-time PCR method was set at 4CFU/25g or mL for both food categories. Relative accuracy (98.33%), specificity (96.77%), and sensitivity (100%) were recorded for the food category "fruit and vegetable-based products" and 93.3%, 88.24%, 100%, respectively, for "dairy products". The RDL according to Fisher's exact test was p=1 for both food categories, for each level, and each food/strain combination. The interlaboratory study results showed correct identification of all 24 blind samples with both methods by all the participating laboratories. The results show that this commercial kit is suitable for the rapid detection of C. jejuni, C. coli, and C. lari on fruit, vegetables and dairy products and may aid in official controls. In conclusion, the use of alternative methods is recommended for the rapid identification of positive samples and the identification of the possible bacterial source in a FBO within 48 h.

Enterotoxin gene profiles of Staphylococcus aureus isolated from milk and dairy products in Italy.

UNLABELLED: Staphylococcal foodborne intoxication, occurring after consumption of staphylococcal enterotoxins (SEs) in food, is considered one of the most common forms of bacterial foodborne outbreaks worldwide. Milk and dairy products account for 5% of all the incriminated foods in staphylococcal outbreaks, referring to Europe. The distribution of genes encoding for enterotoxins in Staphylococcus aureus strains is highly variable, with some carried on stable regions of the chromosome and others carried on mobile genetic elements. The aim of this study was to analyse the distribution of genes encoding for SEs in Staph. aureus strains isolated from milk and dairy products. In the period from January 2010 to June 2011, a total of 1245 dairy samples (848 of raw milk and 397 of dairy products) were collected and analysed for detection of genes encoding for 11 SEs and SEls (SEA, SEB, SEC, SED, SEE, SEG, SEH, SEI, SER SElJ and SElP) according to the procedures of the Italian National Reference Laboratory for coagulase-positive Staphylococci including Staph. aureus. Staphylococcus aureus strains were isolated in 481 (39%) samples. Of the 481 isolates of Staph. aureus tested, 255 (53%) were positive for one or more SE genes, and thirty-five different enterotoxin gene profiles were distinguished among the isolates. ser gene, found in 134 (28%) of the isolates, was the most frequent, followed by sed (25%) and selj genes (25%). The identification of new SEs increased the isolation frequency of enterotoxigenic staphylococci, thus suggesting that the pathogenic potential of Staph. aureus may be of greater importance than previously thought. Further studies are needed to quantify the expression of these new enterotoxins, and to assess their contribution to foodborne disease burden. SIGNIFICANCE AND IMPACT OF THE STUDY: The analyses targeted 11 staphylococcal enterotoxins genes and 35 different enterotoxin gene profiles were distinguished among the isolates. A total of 255 Staph. aureus isolates were positive for one or more SE genes while ser gene was the most prevalent. In 93% of the isolates bearing genes located on the enterotoxin gene cluster (n = 89), both seg and sei genes were present.

Staphylococcal poisoning foodborne outbreak: epidemiological investigation and strain genotyping.

In June 2011, an outbreak of Staphylococcus aureus enterotoxin food poisoning gastroenteritis occurred in Turin, Italy, following a catered dinner party at a private home. Within a few hours, 26 of the 47 guests experienced gastrointestinal illness, and 9 were hospitalized. A retrospective cohort study using a standardized questionnaire was carried out, and the risk ratios for each food item were calculated. The analysis indicated consumption of seafood salad as the most probable cause of the outbreak (risk ratio = 11.72; 95 % confidence interval, 1.75 to 78.54). Biological samples were collected from four of the hospitalized guests (stool and vomit), nasal mucosa swabs from three food handlers employed with the caterer, and available food residuals. All stool and vomit samples tested positive for enterotoxigenic S. aureus. As residues of the seafood salad were no longer available for sampling, suspected contamination could not be verified. However, no other food was found contaminated by S. aureus or its enterotoxins. All isolates from the biological samples were characterized at the genomic level by means of two multiplex PCR protocols to determine the presence of genes encoding staphylococcal enterotoxins, pulsed-field gel electrophoresis and staphylococcal protein A gene (spa) typing to describe their genetic profiles. All the isolates presented genes encoding SEA and SEI; the pulsed-field gel electrophoresis genetic profiles revealed the same pulsotype in the microorganism isolated from the hospitalized guests as in one of the isolates from a food handler's nasal mucosa, and the spa typing analysis reported two closely related spa types (t701 and t267), implicating the food handler as the most likely outbreak source.