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Staphylococcus aureus is responsible for life-threatening conditions, while in the meantime it has rapidly acquired resistance to several antibiotic classes. In the context of an effective empirical antibiotic therapy, an accurate evaluation of the resistance rates of S. aureus may be critical. The aim of this study was to determine the resistance rates of S. aureus in the years 2015-2018 and to assess the impact of specimen stratification on the resistance rates. We have retrospectively analysed S. aureus strains isolated from blood, bronchial aspirate, pus, sputum and urine collected from hospitalized and ambulatory care patients. The comparison between resistance rates from 2015 to 2018 and among different specimens was assessed by Fisher's exact test followed by Benjamini and Hochberg's correction of the p-values. Higher resistance rates were detected for penicillin followed by oxacillin, levofloxacin, erythromycin and clindamycin. Differences in the annual resistance rates were not statistically significant after the BH's correction. The comparison between cumulative S. aureus resistance rates stratified by specimens showed some statistically relevant differences among the five specimen types. In particular, p-values were statistically significant for clindamycin, erythromycin, gentamicin, levofloxacin, oxacillin, penicillin and vancomycin. Annual resistance rates of S. aureus clinical isolates remained constant over the course of time. Moreover, the stratification of the data by specimen may significantly impact on the evaluation of the resistance rates, at least for some antibiotics. Therefore, if the number of data is high, stratification by specimens may be recommendable to better approach an empirical antibiotic therapy.

Klebsiella pneumoniae is a common nosocomial pathogen involved in many infectious diseases such as bacteraemia, urinary and respiratory tract infections. It is responsible for the rise in morbidity and mortality rates since most clinical isolates exhibit resistance to several antibiotics. Moreover, the epidemiology of these nosocomial infections is variable across countries and regions. From January 2015 to December 2017 we retrospectively analysed the bloodstream infections caused by K. pneumoniae strains in hospitalised patients with the aim of studying the temporal trends of wild type (WT), multi-drug resistant (MDR), extended drug resistant (XDR), pan-drug resistant (PDR) and carbapenem-resistant (CR) strains. In all, 439 K. pneumoniae isolates from 356 patients were collected from all units of the Policlinico of Bari. The majority of clinical isolates were collected from the intensive care unit (125, 28.47%), haematology (34, 7.74%), rehabilitation (27, 6.15%) and cardiac surgery wards (25, 5.69%). Moreover, the majority of the isolates were classified as CR (325, 74.03%, 95%CI: 69.61-78.19) and XDR (255, 58.09%, 95%CI: 53.31-62.72). Annual prevalence rates and monthly counts were analysed using the Chi Squared test for trends and the Poisson regression with multiple p-value correction according to Benjamini and Hochberg's procedure. The annual relative frequencies of the XDR and CR K. pneumoniae isolates decreased significantly from 63.37% to 48.44% and from 78.48% to 63.28% respectively, while WT K. pneumoniae significantly increased from 13.95% to 23.44%. Poisson regression analysis confirmed the presence of a decreasing monthly trend for the XDR and CR K. pneumoniae count series. In order to control the spread of antibiotic resistance, more inclusive surveillance data will be needed to either confirm these results or improve antibiotic stewardship measures.

The aim of this study was to determine the frequency of multiple type human papillomavirus (HPV) infections, and whether any types are involved in multiple HPV-type infections (mHPV) more or less frequently than expected. From January 2012 to February 2018, 2848 cervico-vaginal swabs were analysed in the UOC Microbiology and Virology of Policlinico of Bari, Italy. HPV DNA detection was performed using initially nested-polymerase chain reaction (PCR) and subsequently multiplex real-time PCR assay. 1357/2848 samples (47.65%) were HPV DNA positive and 694/1357 (51.14%) showed mHPVs. The median number of mHPVs was 2 (interquartile range: 2-3). HPV-types more frequently detected were 42 (9.97%), 16 (8.92%), 53 (7.23%) and 31 (7.16%). Each detected HPV-type was involved in mHPVs in more than 50% of cases. Statistical analysis showed significant associations for all HPV-types except for 33, 43, 51, 58 and 82 HPV-types. The major number of significant pairwise associations were detected for the types 42 and 70. Only positive associations were detected. Further data are necessary to evaluate the clinical impact of the single combinations.

Clostridium difficile is an emerging cause of healthcare-associated infections. The increasing frequency and severity is attributed to highly virulent ribotypes such as 027. The aim of this study was to retrospectively analyze the prevalence of CDI and ribotype 027 in 481 clinical samples collected from hospitalized patients and sent to the laboratory of molecular biology, UOC Microbiology and Virology, Azienda Ospedaliera-Universitaria, Policlinico of Bari, Italy. Toxins A+B and DNA C. difficile detections were performed using immunochromatographic test and a multiplex real-time PCR assay, respectively. Overall, 37/366 (10.11%) patients were positive at the immunochromatographic assay. This result was confirmed in 31 (8.47%) samples from 31 different patients by molecular assay. Logist regression confirmed age >50 years (adjusted odds ratio [aOR]: 4.29, 95%CI:1.44-18.50) and hospitalization in the Infectious Diseases (aOR: 3.77, 95%CI: 1.34-9.85) ward were risk factors for CDI. The associated 027 ribotype deletion D117tcd was detected in seven (22.58%) of 31 positive patients. Exploratory analysis of monthly prevalence of 027 ribotype suggested a slight increase after August 2015. Our results show that a monitoring program is needed to either better assess the diffusion of CDI and ribotype 027 or also to establish the risk factors associated with the transmission in our healthcare facilities.

Human papillomavirus (HPV) is considered the most important risk factor for the development of ano-genital region cancer in both women and men. Whereas low-risk genotypes are responsible for cutaneous and genital lesions, high-risk genotypes are associated with ano-genital cancer. The aim of this study was to retrospectively analyse the prevalence, genotype distribution and temporal dynamics of HPV infection in 2312 specimens from 2312 subjects (2149 women and 163 men) who attended the laboratory of molecular biology, UOC Microbiology and Virology, Azienda Ospedaliera-Universitaria, Policlinico of Bari, Italy. HPV DNA detection and genotyping was performed using a multiplex real-time PCR assay. In all, 1123/2312 subjects (48.57%) resulted positive for HPV DNA. In particular, HPV DNA was detected in (1056) 49.14% of females and (67) 41.10% of males. HPV co-infections were detected in 565 (24.44%) patients. High-risk and low-risk HPV genotypes were detected in 887 (38.37%) and 600 (25.95%) patients, respectively. The most prevalent HPV genotypes were HPV-42 (10.29%), HPV-16 (8.56%), HPV-31 (7.40%) and HPV-53 (7.14%). Statistically significant differences between female and male patients were not detected. Moreover, HPV prevalence remained constant in time while HPV-16, but not HPV-6, 11 and 18, showed a decreasing trend from 2013 (11.24%) to 2016 (6.67%). Other HPV genotypes showed some complex and different patterns. Our data showed an unusually high frequency of HPV-42 and a high prevalence of HPV infection in the patients analysed. Although evidence of a decreasing trend of HPV-16 could be a consequence of anti-HPV vaccination, corroboration from further studies will be needed. Moreover, the small number of studied males and the similarity to females in terms of HPV prevalence suggest that more active HPV screening and anti-HPV vaccination in the male population should be considered important tools to eliminate HPV sexual transmission.

Schistosomiasis is the most prevalent tropical disease in the world after malaria. According to the World Health Organization, the disease afflicts more than 240 million people in about 80 countries. Recently, an epidemiological surveillance study performed between 1997 and 2010 by the European Network for Tropical Medicine and Health Travel regarding schistosomiasis between immigrants and travelers has been published. No data are available in the literature regarding the situation in South Italy. Herein, we report the prevalence of urinary schistosomiasis in a population of migrants in Apulia referring to our outpatient clinic for immigrant diseases in the period 2006-2016. Since all cases of schistosomiasis were related to the last three years of observation, the demographic and clinical characteristics of the study population were compared before and after 2014. Nearly 51% of all patients visited (1762) were from high/moderate endemic countries for schistosomiasis, and nine cases of urinary schistosomiasis were diagnosed. Prevalence was 1% among migrants from endemic areas and 10% in those from Mali and Senegal. Our findings confirm that schistosomiasis is a widespread infection among immigrants, even if it is often underdiagnosed because of the multifaceted clinical presentation. Changes in migratory dynamics can affect clinical observations very quickly.

Aspergillus section Nigri includes species of interest for animal and human health, although studies on species distribution are limited to human cases. Data on the antifungal susceptibilities and the molecular mechanism of triazole resistance in strains belonging to this section are scant. Forty-two black Aspergillus strains from human patients (16 isolates), animals (14 isolates), and the environment (12 isolates) were molecularly characterized and their in vitro triazole susceptibilities investigated. Aspergillus tubingensis was isolated from humans, animals, and environmental settings, whereas Aspergillus awamori and Aspergillus niger were isolated exclusively from humans. Phylogenetic analyses of β-tubulin and calmodulin gene sequences were concordant in differentiating A. tubingensis from A. awamori and A. niger Voriconazole and posaconazole (PSZ) were the most active triazoles. One A. tubingensis strain was resistant to itraconazole and PSZ and one A. niger strain to PSZ. Sequence analysis of the cyp51A gene revealed different sequence types within a species, and A. tubingensis strains were also phylogenetically distinct from A. awamori/A. niger strains according to the strain origin and susceptibility profile. Genetic analysis of the cyp51A sequences suggests that two nonsynonymous mutations resulting in amino acid substitutions in the CYP51A protein (changes of L to R at position 21 [L21R] and of Q to R at position 228 [Q228R]) might be involved in azole resistance. Though azole resistance in black Aspergillus isolates from animals and rural environments does not represent a threat to public health in Southern Italy, the use of triazoles in the clinical setting needs to better monitored. The cyp51A sequence is useful for the molecular identification of black Aspergillus, and point mutations in protein sequences could be responsible for azole resistance phenomena., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

This study evaluated the diagnostic performances of an ELISA method and a molecular method for the detection of verotoxin in faecal samples during an outbreak of haemolytic-uraemic syndrome (HUS) occurring in Apulia, Southern Italy. Two of the 16 faecal samples were positive for verotoxin when analysed by ELISA and resulted PCR positive for stx1, stx2, eaeA and serogroup O26. The other 14 faecal samples resulted negative with both tests. The detection of verotoxin in faecal samples by ELISA is a simple, sensitive, specific and rapid method (2 hours) of considerable utility for routine clinical testing laboratories without access to more specialized diagnostic procedures.

Background: The aim of this study was the rapid identification of bla KPC gene in 38 Klebsiella pneumoniae clinical isolates with reduced susceptibility to carbapenems. The modified Hodge Test (MHT) was carried out to phenotypically determine whether resistance to carbapenems was mediated by a carbapenemase. The detection of the bla KPC gene was performed by real-time acid nucleic sequence-based amplification (NASBA™™), specifically designed for the detection of KPC RNA target., Results: Thirty-two/38 isolates evaluated by MHT showed the production of carbapenemases, while all the strains exhibited the production of KPC by inhibition test with phenylboronic acid (the combined disk test with IPM/IPM plus phenylboronic acid). The detection of bla KPC gene by Nuclisens EasyQ KPC yielded positive results in 38/38 (100%) strains. The presence of bla KPC gene was confirmed in all K. pneumoniae isolates when tested by the gold standard PCR assay., Conclusions: In consideration of the serious challenge represented by infections due to K. pneumoniae it appears necessary the rapid identification of carbapenemases in clinical settings as it is made possible by the use of NASBA™ assay.

The lack of rapidity and the low sensitivity and specificity of traditional laboratory methods limits their usefulness in the laboratory diagnosis of viral central nervous system (CNS) infections. This study describes the use of a commercially available multiplex polymerase chain reaction (mPCR)-based reverse hybridization assay (RHA) for the simultaneous detection of the genomes of 8 viruses and Toxoplasma gondii in cerebrospinal fluids (CSF) from 181 patients suspected of having viral meningitis. Twenty-two/181 (12.15%) CSF samples resulted positive by mPCR. Eighteen/22 were positive for 1 viral pathogen, whereas a dual infection was detected in 4/22 samples. Epstein-Barr virus (EBV) was the most commonly detected virus (6/22), followed by herpes simplex virus type-1 (HSV-1) (5/22) and -2 (HSV-2) (4/22). Cytomegalovirus (CMV), human herpesvirus-6 (HHV-6), and Epstein-Barr virus (EBV) were detected in 1 specimen each. Two CSF samples were co-infected by HSV-1/HSV-2, 1 sample by HHV-6/T. gondii, and 1 sample by EBV/EV, respectively. Our data support the usefulness of mPCR as a rapid molecular method for the simultaneous detection of major viral pathogens and T. gondii in aseptic meningitis also to allow the earlier application of specific antiviral therapy.

Cat scratch disease (CSD) is a relatively new diagnosed illness with clinical signs of self-limiting regional lymphadenopathy accompanied by symptoms of fever and malaise, to encephalopathy and neuropathy, occurring after a cat scratch or flea bite. Bartonella henselae is now accepted as the etiologic agent of CSD. From January 1994 to September 1998, 412 patients were evaluated for suspect CSD in Italy. Sera were tested for antibodies to B. henselae by a commercially available indirect immunofluorescent assay (IFA), based on B. henselae-infected Vero-cells as the antigen substrate. Of the 412 patients, 26 (6.3%) were considered positive having titers of immunoglobulin G (IgG) to B. henselae of 64 or higher. In these patients CSD was indeed confirmed by either histopathologic examination of lymph nodes biopsy or fourfold raise in antibody titers. Nevertheless, sera were tested by IFA for Afipia felis and one showed a double reactivity to B. henselae and A. felis. Finally, three sera, negative to B. henselae serology, were positive to A. felis. Three hundred and eighty-six patients received alternative diagnoses. One hundred and twenty-five serum samples from control subjects were negative by IFA for either B. henselae or A. felis. Moreover, a cross-reactivity with sera from patients affected by other diseases was not observed. Our study shows that the ascertained cases of CSD are etiologically determined by B. henselae, IFA assay is confirmed as a useful tool in the laboratory diagnosis and, over a 5 years period of study, the incidence of CSD in Italy has been low.

Phenotypic heterogeneity among isolates of Eubacterium lentum has been recognized for many years. To better delineate their taxonomic relatedness, 29 clinical isolates of E. lentum were examined for soluble-protein content, cellular fatty acid profile, and antimicrobial resistance pattern in order to ascertain whether differences in these characteristics could be correlated with differences in biochemical activities. Among 29 isolates we could identify 6 that were different from all the others. These strains were coccobacilli with translucent colonies; they were catalase and H2S negative, not fluorescent under UV light, and susceptible to beta-lactam drugs; growth was not stimulated by arginine; and fatty acid analysis revealed the presence of straight-chain fatty acids. The remainder of the strains, including the type species, were pleomorphic bacilli with speckled colonies and were catalase and H2S positive; all but two were fluorescent under UV light; they were resistant to beta-lactam antibiotics; growth was greatly stimulated by arginine; and they demonstrated saturated branched-chain fatty acids. Our data suggest that E. lentum can be further differentiated into different types.

OBJECTIVE: To evaluate the new non-radioactive automated method BACTEC 9000 MB system for the rapid detection of mycobacteria in clinical specimens. METHODS: Ninety clinical specimens from 90 patients with a clinical diagnosis of tuberculosis were tested by both BACTEC 9000 and standard microbiological methods, and the results compared. RESULTS: The BACTEC 9000, in comparison with the standard method, showed significantly higher detection rates (45 of 90 positive versus 34), shorter time to culture positivity (mean time 18.8 versus 27.4 days) and lower contamination rate (2.2% versus 5.5%). CONCLUSIONS: These results encourage the use of this new system and suggest its use in microbiological laboratories involved in mycobacteriology.

Antibiotic resistant pneumococci have been reported from all continents. Because of the importance of pneumococci in the aetiology of life-threatening diseases, the screening for penicillin resistance with oxacillin disc on all clinically significant isolates is suggested. However, discrepancy between the determination of penicillin resistance by oxacillin disc diffusion and the determination of penicillin minimum inhibitory concentration (MIC) has been reported. On this basis we have examined seven strains of Streptococcus pneumoniae isolated from patients recovered for the exacerbation of chronic bronchitis which were oxacillin-resistant. The assay of penicillin MICs showed that three isolates were moderately resistant to this agent, while four isolates resulted sensitive to penicillin as well as to cefotaxime. These results suggest that a further evaluation of penicillin MIC should be performed on those strains of S. pneumoniae resulting oxacillin-resistant.

The in vitro effect of a virulent and a nonvirulent strain of Leptospira interrogans serotype icterohaemorrhagiae on human peripheral mononuclear cells was investigated. After addition of bacteria to citrated whole blood the production of mononuclear cell procoagulant activity (tissue factor) was observed. Indeed mononuclear cells isolated from whole blood bacteria mixtures after prolonged incubation shortened the recalcification time of normal plasma. The virulent strain induced a significantly higher procoagulant activity than nonvirulent and this effect was dependent on the number of bacteria. The production of tissue factor, a potent trigger of blood coagulation, by Leptospira icterohaemorrhagiae could help to understand the mechanism(s) responsible for the activation of intravascular coagulation associated with leptospirosis.