Enterobacterales carrying chromosomal AmpC β-lactamases in Europe (EuESCPM): Epidemiology and antimicrobial resistance burden from a cohort of 27 hospitals, 2020-2022

INTRODUCTION

The ESCPM group (Enterobacter species including Klebsiella aerogenes - formerly Enterobacter aerogenes, Serratia species, Citrobacter freundii complex, Providencia species and Morganella morganii) has not yet been incorporated into systematic surveillance programs.

METHODS

We conducted a multicentre retrospective observational study analysing all ESCPM strains isolated from blood cultures in 27 European hospitals over a 3-year period (2020-2022). Diagnostic approach, epidemiology, and antimicrobial susceptibility were investigated.

RESULTS

Our study comprised 6,774 ESCPM isolates. MALDI-TOF coupled to mass spectrometry was the predominant technique for bacterial identification. Susceptibility to new β-lactam/β-lactamase inhibitor combinations and confirmation of AmpC overproduction were routinely tested in 33.3% and 29.6% of the centres, respectively. The most prevalent species were E. cloacae complex (44.8%) and S. marcescens (22.7%). Overall, third-generation cephalosporins (3GC), combined third- and fourth-generation cephalosporins (3GC + 4GC) and carbapenems resistance phenotypes were observed in 15.7%, 4.6%, and 9.5% of the isolates, respectively. AmpC overproduction was the most prevalent resistance mechanism detected (15.8%). Among carbapenemase-producers, carbapenemase type was provided in 44.4% of the isolates, VIM- (22.9%) and OXA-48-enzyme (16%) being the most frequently detected. E. cloacae complex, K. aerogenes and Providencia species exhibited the most notable cumulative antimicrobial resistance profiles, with the former displaying 3GC, combined 3GC + 4GC and carbapenems resistance phenotypes in 15.2%, 7.4%, and 12.8% of the isolates, respectively. K. aerogenes showed the highest rate of both 3GC resistant phenotype (29.8%) and AmpC overproduction (32.1%), while Providencia species those of both carbapenems resistance phenotype (42.7%) and carbapenemase production (29.4%). ESCPM isolates exhibiting both 3GC and combined 3GC + 4GC resistance phenotypes displayed high susceptibility to ceftazidime/avibactam (98.2% and 95.7%, respectively) and colistin (90.3% and 90.7%, respectively). Colistin emerged as the most active drug against ESCPM species (except those intrinsically resistant) displaying both carbapenems resistance phenotype (85.8%) and carbapenemase production (97.8%).

CONCLUSIONS

This study presented a current analysis of ESCPM species epidemiology in Europe, providing insights to inform current antibiotic treatments and guide strategies for antimicrobial stewardship and diagnostics.

Seasonal Variation in Fungi in Beach Sand in Summertime: Stintino (Italy)

BACKGROUND

The goal of this study was to monitor the microbial biodiversity in beach sand that is heavily visited by tourists during the summer, and to determinate whether the high presence of bathers (around 5000 per day) can modify sand microbial composition.

METHODS

Between 2016 and 2020, 150 sand samples were collected from nine different points at La Pelosa beach in Sardinia, Italy. Non-culturing methods were used; DNA extraction and meta-barcode sequencing were performed. All samples were analyzed with sequencing methods for 16S and ITS sequences.

RESULTS

Fungal genera differ on the three beaches and in the winter/summer zones. The ITS sequence showed the most common presence of Candida during summer and Paradendryphiella in the winter. The greatest diversity was found in the dune during winter, while in other parts of the beach, there are differences between bacteria and fungi, particularly in the wash zone during the winter, with high diversity for 16S sequences but low diversity for ITS sequences.

CONCLUSIONS

It appears reasonable that the sands, even on non-urban beaches, should be included in health monitoring programs in addition to the waters, and that access to them should be regulated by limiting the number of bathers with the aim of reducing the presence of pathogenic fungal species.

Diagnosis of Chronic Pulmonary Aspergillosis: Clinical, Radiological or Laboratory?

Chronic pulmonary aspergillosis (CPA) is a chronic progressive lung disease associated with a poor prognosis and a 5-year mortality rate of approximately 40-50%. The disease is characterized by slowly progressive destruction of the lung parenchyma, in the form of multiple cavities, nodules, infiltrates or fibrosis. CPA can be challenging to diagnose due to its non-specific symptoms and similarities with other respiratory conditions combined with the poor awareness of the medical community about the disease. This can result in delayed treatment even for years and worsening of the patient's condition. Serological tests certainly play a significant role in diagnosing CPA but cannot be interpreted without radiological confirmation of CPA. Although many data are published on this hot topic, there is yet no single definitive test for diagnosing CPA, and a multidisciplinary approach which involves a combination of clinical picture, radiological findings, microbiological results and exclusion of other mimicking diseases, is essential for the accurate diagnosis of CPA.

Polyclonal Multidrug ESBL-Producing Klebsiella pneumoniae and Emergence of Susceptible Hypervirulent Klebsiella pneumoniae ST23 Isolates in Mozambique

Globally, antibiotic-resistant Klebsiella spp. cause healthcare-associated infections with high mortality rates, and the rise of hypervirulent Klebsiella pneumoniae (hvKp) poses a significant threat to human health linked to community-acquired infections and increasing non-susceptibility. We investigated the phenotypic and genetic features of 36 Klebsiella isolates recovered from invasive infections at Hospital Central of Maputo in Mozambique during one year. The majority of the isolates displayed multidrug resistance (MDR) (29/36) to cephalosporins, gentamicin, ciprofloxacin, and trimethoprim-sulfamethoxazole but retained susceptibility to amikacin, carbapenems, and colistin. Most isolates were ESBLs-producing (28/36), predominantly carrying the blaCTX-M-15 and other beta-lactamase genes (blaSHV, blaTEM-1, and blaOXA-1). Among the 16 genomes sequenced, multiple resistance genes from different antibiotic classes were identified, with blaCTX-M-15, mostly in the ISEcp1-blaCTX-M-15-orf477 genetic environment, co-existing with blaTEM-1 and aac(3)-IIa in five isolates. Our results highlight the presence of polyclonal MDR ESBL-producing K. pneumoniae from eight sequence types (ST), mostly harbouring distinct yersiniabactin within the conjugative integrative element (ICE). Further, we identified susceptible hvKp ST23, O1-K1-type isolates carrying yersiniabactin (ybt1/ICEKp10), colibactin, salmochelin, aerobactin, and hypermucoid locus (rmpADC), associated with severe infections in humans. These findings are worrying and underline the importance of implementing surveillance strategies to avoid the risk of the emergence of the most threatening MDR hvKp.

Azole non-susceptible C. tropicalis and polyclonal spread of C. albicans in Central Vietnam hospitals

INTRODUCTION

Candida spp. are responsible for infections ranging from local to systemic, and resistance to antifungal first-line therapy is increasing in non-albicans Candida species. We aimed to determine the etiology of candidiasis and the antifungal resistance of Candida spp. isolated in Hue hospitals, Central-Vietnam.

METHODS

Species identification was performed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry supported by fungal internal-transcribed-spacer amplification and sequencing. Antifungal susceptibility testing was performed by disk diffusion method and minimum inhibitory concentrations of azoles, caspofungin, and amphotericin B against C. tropicalis were determined by broth microdilution. Polymorphism of erg11 gene associated with fluconazole resistance was carried out by polymerase chain reaction and sequencing. Multilocus sequence typing (MLST) was used for typing selected C. albicans isolates.

RESULTS

Overall, 196 Candida isolates were detected, mostly C. albicans (48%), followed by C. tropicalis (16%), C. parapsilosis (11%), C. glabrata (9%), C. orthopsilosis (6%) and to a lesser extent another eight species. High rates of resistance to fluconazole and voriconazole (18.8%) were observed in C. tropicalis with five isolates co-resistant to both agents. Y132F and S154F missense mutations in the ERG11 protein were associated with fluconazole-resistance in C. tropicalis (67.7%). Resistance to caspofungin was found in one isolate of C. albicans. MLST identified a polyclonal population of C. albicans with multiple diploid sequence types, and with few lineages showing potential nosocomial spread.

CONCLUSIONS

Resistance to triazole agents should be considered in C. tropicalis infections in the studied hospitals, and surveillance measures taken to avoid Candida diffusion.

Acute hepatitis in a paediatric patient: immune-mediated drug-induced liver injury or albendazole-induced autoimmune hepatitis?

INTRODUCTION

Drug-induced liver injury (DILI) is one of the most common causes of liver damage. A large number of drugs, dietary supplements, and herbal medications can cause hepatotoxicity. In some situations, it is difficult to distinguish between DILI and autoimmune hepatitis, especially when the mechanism is immune-mediated. Albendazole is a drug that has been used for decades for the treatment of parasitic infections in humans. One of the side effects is liver enzyme elevation, but rarely requires the discontinuation of therapy. Previous experience has shown that hypersensitivity is the most common mechanism of albendazole hepatotoxicity.

CASE REPORT

Here we presented a paediatric patient in whom albendazole induced severe liver injury. In laboratory analyses, in addition to markedly elevated transaminases and parameters of cholestasis, there was also a significant increase in IgG, so autoimmune hepatitis was considered. Even though the liver histology indicated toxic liver disease, prednisolone was started. Corticosteroid therapy resulted in the complete normalization of liver function, as well as IgG. With the cessation of corticosteroid therapy, transaminases, bilirubin and gamma-glutamyl transferase (GGT) remained within normal levels, but an increase in anti-smooth muscle antibodies (SMA) was noted in immunological analyses after one year of follow-up.

CONCLUSIONS

Immune-mediated hepatotoxicity from albendazole is one possible mechanism of liver injury. The use of albendazole in the treatment of parasitic infections, especially in children, requires close monitoring. The question remains as to whether albendazole is a drug that can induce autoimmune hepatitis in the paediatric population.

Metagenomic detection of eumycetoma causative agents from households of patients residing in two Sudanese endemic villages in White Nile State

Eumycetoma is a chronic debilitating fungal disease endemic to tropical and subtropical regions, with Sudan featuring the highest eumycetoma incidence. Among the 50 species of fungi most commonly associated with eumycetoma Madurella mycetomatis (M. mycetomatis) is often referenced as the most common pathogen. However, there is an enormous knowledge gap related to this neglected disease and its pathogenesis, epidemiological features, and host-specific factors that could contribute to either the host susceptibility and resistance. In this study, we were able to utilize a metagenomic approach and samples collected from clinical black grains (BG) and familiar household environments aimed to assay both the habitat of eumycetoma-associated fungi and its possible connection with eumycetoma patients living in two different eumycetoma endemic villages within the White Nile State of Sudan. DNA sequencing targeting the fungal ITS2 domain was performed on soil, animal dung, housing walls and roofs, and Acacia-species thorn samples and compared with culture-dependent methods of fungal isolation. Additionally, we compared the soil samples obtained in the endemic zone with that from non-endemic zones, including Wagga village in Kassala State and Port Sudan suburb in Port Sudan State. Overall, a total of 392 Amplicon Sequence Variants (ASVs) were detected by ITS2 metagenomics Eumycetoma causative organisms accounted for 10% of total ASVs which included 11 genera: Exserohilum (2%), Aspergillus (1.7%), Curvularia (1%), Alternaria (0.9%), Madurella (0.5%), Fusarium (0.4%), Cladosporium (0.2%) Exophiala (0.15%), and, in a lesser extent, Microascus (0.05%) Bipolaris and Acremonium (0.01%) for each. Only five genera were identified by culture method, which included Fusarium (29%), Aspergillus (28%), Alternaria (2.5%), Bipolaris (1.6%), and Chaetomium (0.8%). M. mycetomatis was detected within all the studied patients’ houses, accounting for 0.7% of total sequences. It was the first common eumycetoma-associated agent detected in soil samples and the third common in the dung and wall samples. In contrast, it was not detected in the roof or thorn samples nor in the soils from non-endemic regions. Exserohilum rostratum, Aspergillus spp and Cladosporium spp were detected in all samples. M. mycetomatis and other eumycetoma-associated fungal identified in the patients’ black grains (BG) samples by metagenomics were identified in the environmental samples. Only Acremonium alternatum and Falciformispora senegalensis, responsible for eumycetoma in two patients were not detected, suggesting the infections in these patients happened outside these endemic areas. The soil, animal dung, and houses built from the same soil and dung are the main risk factors for M. mycetomatis infection in these endemic villages. Furthermore, the poor hygienic and environmental conditions, walking barefooted, and the presence of animals within the houses increase the risk of M. mycetomatis and other fungi causing eumycetoma.

In this pilot study, using a metagenomic approach, we revealed in two Sudanese eumycetoma endemic villages within the While Nile State in Sudan, the habitat of M. mycetomatis and other fungal species responsible for eumycetoma. Although never isolated in culture, M. mycetomatis represented the most abundant eumycetoma-associated species found within soil samples and the third most common species within dung and housing wall samples. All the eumycetoma-associated fungal species detected by metagenomic in black grains samples were identified in patient’s houses, except Falciformispora senegalensis and Acremonium alternatum. The findings obtained in this study provided insight into the habitat of eumycetoma-associated causative species and improved knowledge on eumycetoma origin and risk factors in endemic villages. Furthermore, despite the limited number of samples, these results suggest the main prevention measurements to contain eumycetoma in these endemic areas. These measurements include using gloves and alternative materials to endemic soil and animal dung in building the wall of the houses walls, constructing animal fences and appropriate use of footwear.

Genomic Snapshot of SARS-CoV-2 in Migrants Entering Through Mediterranean Sea Routes

In December 2019, a novel coronavirus emerged in Wuhan, China, rapidly spreading into a global pandemic. Italy was the first European country to experience SARS-CoV-2 epidemic, and one of the most severely affected during the first wave of diffusion. In contrast to the general restriction of people movements in Europe, the number of migrants arriving at Italian borders via the Mediterranean Sea route in the summer of 2020 had increased dramatically, representing a possible, uncontrolled source for the introduction of novel SARS-CoV-2 variants. Importantly, most of the migrants came from African countries showing limited SARS-CoV-2 epidemiological surveillance. In this study, we characterized the SARS-CoV-2 genome isolated from an asymptomatic migrant arrived in Sardinia via the Mediterranean route in September 2020, in comparison with SARS-CoV-2 isolates arrived in Sicily through the Libyan migration route; with SARS-CoV-2 isolates circulating in Sardinia during 2020; and with viral genomes reported in African countries during the same summer. Results showed that our sequence is not phylogenetically related to isolates from migrants arriving in Sicily, nor to isolates circulating in Sardinia territory, having greater similarity to SARS-CoV-2 genomes reported in countries known for being sites of migrant embarkation to Italy. This is in line with the hypothesis that most SARS-CoV-2 infections among migrants have been acquired prior to embarking to Italy, possibly during the travel to or the stay in crowded Libyan immigrant camps. Overall, these observations underline the importance of dedicated SARS-CoV-2 surveillance of migrants arriving in Italy and in Europe through the Mediterranean routes.

"Swab Team" in the SARS-CoV-2 outbreak containment among healthcare workers

INTRODUCTION

To analyze the virus spread among Sassari Hospital staff in the first Covid-19 wave and the impact of the Swab Team, a multidisciplinary task force entitled of nasopharyngeal swab collection and testing.

METHODOLOGY

Nasopharyngeal swabs from HCWs between March 6 and May 28 2020 are evaluated.

RESULTS

4919 SARS-CoV-2 tests were performed on 3521 operators. Nurses and doctors are the categories at highest risk. After the Swab Team institution, the average number of swabs raised from 47/day to 86/day (p = 0.007). Positive samples decreased from 18.6% to 1.7% (p < 0.0001).

CONCLUSIONS

The Swab Team is effective in increasing the cases tested and in reducing the reporting time. Procedure standardization reduces the risk for all the subjects involved (no transmission among swab team members, nor during the sample collection).

Metagenomics of black grains: new highlights in the understanding of eumycetoma

BACKGROUND

Eumycetoma is a chronic subcutaneous granulomatous disease that is endemic in Sudan and other countries. It can be caused by eight different fungal orders. The gold standard diagnostic test is culture, however, culture-independent methods such as imaging, histopathological and molecular techniques can support diagnosis, especially in cases of negative cultures.

METHODS

The amplicon-based internal transcribed spacer 2 metagenomic technique was used to study black grains isolated from 14 tissue biopsies from patients with mycetoma. Furthermore, mycological culture and surgical biopsy histopathological examinations of grains were performed.

RESULTS

Madurella mycetomatis (n=5) and Falciformispora spp. (n=4) organisms were identified by culture and confirmed by metagenomics. Metagenomics recognised, at the species level, Falciformispora as Falciformispora tompkinsii (n=3) and Falciformispora senegalensis (n=1), while in culture-negative cases (n=5), Madurella mycetomatis (n=3), Falciformispora senegalensis (n=1) and Fusarium spp. (n=1) were identified. Interestingly, the metagenomics results showed a 'consortium' of different fungi in each sample, mainly Ascomycota phylum, including various species associated with eumycetoma. The microbial co-occurrence in eumycetoma showed the co-presence of Madurella with Trichoderma, Chaetomium, Malasseziales and Sordariales spp., while Falciformispora co-presented with Inocybe and Alternaria and was in mutual exclusion with Subramaniula, Aspergillus and Trichothecium.

CONCLUSION

Metagenomics provides new insights into the aetiology of eumycetoma in samples with negative culture and into the diversity and complexity of grains mycobiota, calling into question the accuracy of traditional culture for the identification of causative agents.

Extraintestinal Pathogenic Escherichia coli ST405 Isolate Coharboring blaNDM-5 and blaCTXM-15: A New Threat in Mozambique

The development of carbapenem resistance in extraintestinal pathogenic Escherichia coli (ExPEC) has significant clinical implications, particularly in countries where second-line antimicrobials are not readily available, rendering treatments ineffective, and ExPEC infections untreatable. Thus, early detection of high-risk ExPEC lineages and raising awareness of the specific mechanisms underlying carbapenem resistance are mandatory for the selection of appropriate treatment options and the prevention of E. coli spread. This study aims to investigate the phenotypic and genotypic features of the first NDM-5 carbapenemase-producing ExPEC strain isolated from the blood of a patient admitted to the Maputo Central Hospital (MCH), in Mozambique. E. coli SSM100 isolate was identified by MALDI-TOF, it displayed high-level resistance to third generation cephalosporins, carbapenems, fluoroquinolones, and aminoglycosides, performing antimicrobial susceptibilities testing by VITEK 2 system. E. coli SSM100 isolate was classified through whole-genome sequencing as ST405-D-O102: H6, a globally distributed lineage associated with antimicrobial resistance, carrying the blaNDM-5 gene located on an F1:A1:B49 plasmid, coharboring blaCTX-M-15, blaTEM-1, aadA2, sul1, and dfrA12 genes. In addition, mutations in gyrA (S83L and D87N), parC (S80I and E84V), and parE (I529L) conferring fluoroquinolone resistance were also found. Moreover, SSM100 isolate carried 88 virulence genes, of which 28 are reported to be associated with UPEC. The emergence of NDM-5 carbapenemase in a pandemic ST405-D-O102:H6 clone in Mozambique is of great concern. Locations of extended-spectrum β-lactamase determinants and NDM-5 carbapenemase gene on IncF-plasmid can increase their spread reinforcing the need for antimicrobial surveillance and the urgent introduction of carbapenemase detection tests in diagnostic laboratories of the country.

Multi-parasite infection in an immigrant from Ghana: potential for new epidemic foci

INTRODUCTION

Imported parasitosis, which do not require an invertebrate vector, are extremely dangerous and can lead to the occurrence of disease in currently parasite free areas. In the present study we report a case of multi-parasitic infection in a young immigrant from Ghana to Italy caused by filaria, Schistosoma sp. and Strongyloides sp.

CASE PRESENTATION

A 27-year-old Ghanaian man attended the Hospital of Nuoro (Sardinia), Italy, at the end of August 2015, claiming pain to the kidney and hypertensive crisis; the patient presented with dyspnea and epistaxis, chronic itchy skin of the back, shoulders, arms and legs, anuria and high creatinine, metabolic acidosis and hypereosinophilic syndrome. Serological test for parasitic infections were done, and showed a marked positivity for filaria, Schistosoma sp. and Strongyloides sp. The patient started the treatment immediately with two doses per day of Bassado Antibiotic (tetracycline) for twenty days and then with a single dose of 3 mg of ivermectin that was repeated after 3 months.

CONCLUSIONS

Immigrant patients from endemic areas who show clinical signs, such as a general itching on the back, shoulders and arms and legs, should have a thorough history in order to make early diagnosis and prevent further complications. Therefore, general practitioners and doctors in Europe and in other parasitosis non-endemic countries, should consider to test for parasites in any immigrant from endemic countries to aid in establishing the final diagnosis and prevent further complications.

Short epidemiological overview of the current situation on COVID-19 pandemic in Southeast European (SEE) countries

We are living in times where a viral disease has brought normal life in much of the world to a halt. The novel coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease 2019 (COVID-19) started in December 2019 in Wuhan, China initially and in a short time crossed the European borders. After mitigating the epidemic in China, Italy became one of the most COVID-19 affected countries worldwide. International travelers are important sources of infectious diseases and a possible source of epidemic. Due to its political, geographic, and cultural similarities, Italy is one of the main economic partners of Southeast European (SEE) countries. Our data show that infection in index cases in all 11 SEE countries was travel-related with Italy being a source country for 8/11 countries. After the first case identifications on February 25, the number of cases in SEE countries is continually rising reaching the total number of 15,612 with 565 fatal cases and overall case fatality ratio (CFR) of 3.6 (median 3.8, range 0.8-5.5) by April 10, 2020. At a time when the COVID-19 pandemic is approaching its peak, apart from the problems with treatment of the disease and care for critically ill patients, there are other equally important problems, such as organization of outbreak response, provision of health care, lack of hospital personnel, disruption of personal protective equipment supply chains and health care workers (HCWs) protection. But what is more important is the heroic behavior of the HCWs who are showing their humanity by disregarding their lives.

Lyme Endocarditis as an Emerging Infectious Disease: A Review of the Literature

Lyme endocarditis is extremely rare manifestation of Lyme disease. The clinical manifestations of Lyme endocarditis are non-specific and can be very challenging diagnosis to make when it is the only manifestation of the disease. Until now, only a few cases where reported. Physicians should keep in mind the possibility of borrelial etiology of endocarditis in endemic areas. Appropriate valve tissue sample should be sent for histopathology, culture, and PCR especially in case of endocarditis of unknown origin PCR on heart valve samples is recommended. With more frequent PCR, Borrelia spp. may be increasingly found as a cause of infective endocarditis. Prompt diagnosis and treatment of Lyme carditis may prevent surgical treatment and pacemaker implantations. Due to climate change and global warming Lyme disease is a growing problem. Rising number of Lyme disease cases we can expect and rising number of Lyme endocarditis.

Risk factors associated with poor clinical outcome in pyogenic spinal infections: 5-years' intensive care experience

INTRODUCTION

Management of pyogenic spinal infections (PSI) after the development of neurological deficit has not been specifically addressed in the literature. We aimed to describe real-life clinical outcomes of PSI in patients admitted to an intensive care unit with neurological deficit and identify factors associated with good prognosis.

METHODOLOGY

Consecutive patients admitted to ICU with a possible diagnosis of spinal infection over five years' period were included. Descriptive statistics were performed to examine the demographics and clinical parameters.

RESULTS

The majority (71%) of patients were male. The mean age was 57.4 years (27-79), and 71% were > 50 years old. At least one underlying risk factor was identified in 68% of the patients; the most common comorbidity was diabetes mellitus (DM). All patients have presented with fever accompanied by a neurological deficit (86%) and back pain (79%). A complete recovery was achieved in 25% of patients. However, the majority of patients had adverse outcomes with 21.4% mortality, and 43% remaining neurological sequelae. Increased age with a cut-off of 65 years and pre-existing DM were identified as being associated with poor outcome.

CONCLUSION

Mortality among patients admitted to ICU with PSI was significantly higher than reported in the literature. The residual neurological deficit was common, one-third of patients had remaining neurological sequelae, and only one-fourth had complete recovery. Increased age and background DM were the most important determinants of poor clinical outcome. The impact of DM appears to be much more important than currently recognised in this population.

An exceptional case report of disseminated cryptococcosis in a hitherto immunocompetent patient

Cryptococcosis is an opportunistic fungal infection causes significant disease predominantly in immunocompromised patients. Here we present an excepcional case of disseminated cryptococcosis with pulmonary and cerebral involvement in an immunocompetent patient with no apparent predisposing factors at the time of hospital admission. We described a case of an apparently immunocompetent 66-years old man admitted to hospital with a one-month history of cough, fever and vertigo. During hospitalization, thorax imaging was suggestive of lung metastasis, therefore, he went through several investigations. During hospitalization, he developed neurological symptoms and subsequently underwent a lumbar puncture. Cerebrospinal fluid (CSF) culture was positive for Cryptococcus spp. isolated on Sabouraud's dextrose agar and bird seed agar. In addition, the direct microscopy examination was positive for the India ink test, as well as with the latex agglutination test for cryptococcal polysaccharide antigen (CrAg) in CSF, while serum CrAg was negative. Despite the absence of classic immunocompromising features, he was treated with amphotericin B and fluconazole due to suspected disseminated cryptococcal infection. Later, he was diagnosed with prostatic adenocarcinoma. Upon successful completion of treatment for disseminated cryptococcosis, the patient underwent radical prostate ablation surgery as a treatment forprostatic adenocarcinoma. This exceptional case emphasizes the high degree of suspicion of atypical infections, and in these cases, it is particularly important to consider fungal infections in hitherto healthy patients with no apparent predisposing factors. Although Cryptococcus spp. is predominantly reported in patients with hematological malignancies, cryptococcosis investigation should also be considered as part of the initial workup of patients with a new diagnosis of a solid tumour prior to chemotherapy or radiotherapy.

A rare case of pacemaker lead endocarditis successfully treated with open heart surgery

BACKGROUND

Cardiac device-related endocarditis has emerged as a serious complication in the era of advanced medical technology. Pacemaker related infections are rare and life-threatening with incidence from 0.06% to 7% and high mortality rate (30-35%). Diagnosis is hard, frequently delayed and could be even missed due to poor clinical findings. The average delay in diagnosis is 5.5 month. We report a case of the late-onset of pacemaker lead endocarditis caused by S. epidermidis successfully treated with open heart surgery.

CASE REPORT

Patient with persistent high fever for 11 month and suspicion for infective endocarditis was admitted in Cardiovascular Institute. No clinical signs of endocarditis were observed. TTE revealed large vegetation 30 × 17 mm attached to the atrial electrodes with high embolic potential. This finding was verified by transesophageal echocardiography (TEE), although CT scan did not reveal vegetation. Blood cultures were negative. A sternotomy with cardiopulmonary bypass was performed and electrodes were extracted with large vegetation. Intraoperative finding revealed large thrombus with vegetation around pacemaker leads. Cultures of the electrodes and vegetation revealed Staphylococcus epidermidis. Surgery was followed up with antibiotic treatment for 6 weeks. He has been followed up for the next 2 years, and without complications.

CONCLUSION

The absence of criteria for endocarditis and negative blood cultures should not keep the physician from ruling out lead endocarditis. This complication carries high risk of mortality if left untreated.

Biodiversity of fungi in hot desert sands

The fungal community of six sand samples from Saudi Arabia and Jordan deserts was characterized by culture-independent analysis via next generation sequencing of the 18S rRNA genes and by culture-dependent methods followed by sequencing of internal transcribed spacer (ITS) region. By 18S sequencing were identified from 163 to 507 OTUs per sample, with a percentage of fungi ranging from 3.5% to 82.7%. The identified fungal Phyla were Ascomycota, Basal fungi, and Basidiomycota and the most abundant detected classes were Dothideomycetes, Pezizomycetes, and Sordariomycetes. A total of 11 colonies of filamentous fungi were isolated and cultured from six samples, and the ITS sequencing pointed toward five different species of the class Sordariomycetes, belonging to genera Fusarium (F. redolens, F. solani, F. equiseti), Chaetomium (C. madrasense), and Albifimbria (A. terrestris). The results of this study show an unexpectedly large fungal biodiversity in the Middle East desert sand and their possible role and implications on human health.

Helicobacter pylori 23S rRNA gene mutations associated with clarithromycin resistance in chronic gastritis in Vietnam

Introduction: Data about the prevalence of the A2142C, A2142G, and A2143G mutations in 23S rRNA gene is still limited. The aim of this study was to determine the prevalence of these mutations in 23S rRNA gene of H. pylori vietnamese strains. Methodology: One hundred and sixty-nine patients with H. pylori-positive chronic gastritis were examined. H. pylori was detected by rapid urease test and Polymerase chain reaction (PCR). Total DNA was extracted from gastric biopsy specimens. A2142C, A2142G, and A2143G mutations were detected by DNA sequencing and PCR-restriction fragment length polymorphism (PCR-RFLP). Results: A2143G mutation was detected in 36.1% of samples, A2142G mutation in 3.6%, while A2142C mutation was not found in any case. The mixture of wild-type and mutation strains was found in 50% of specimens with A2142G, in 23% of specimens with A2143G mutation. There was no association of 23S rRNA gene point mutations with gender or age. However, an association between the heterogeneity of mutation and age was evidenced, with mean age of the group of pure A2143G higher than the group of wild-type/A2143G mixture, and rate of the wild-type/A2143G mixture higher in patients under 40 years of age. Conclusion: A2143G mutation was prominent, while A2142C mutation was not found in the 23S rRNA gene. PCR-RFLP has revealed a reliable assay allowing a rapid and cost-effective detection of clarithromycin-resistant strains. This is useful in countries as Vietnam with high prevalence of clarithromycin-resistance before choosing optimal therapy for H. pylori eradication.

An Algerian perspective on non-typhoidal Salmonella infection

Non-typhoidal Salmonella (NTS) represents a leading cause of food-borne disease worldwide. It is a global public health concern: more than 94 million cases and 115,000 deaths are reported every year, with a disproportionate impact in developing countries. The prevalence of multi-drug-resistant (MDR) Salmonella strains is another major health concern which affects antimicrobial treatment, as many studies report that infections caused by MDR strains are more severe than those caused by susceptible strains. In Algeria, NTS represent one of the primary causes of salmonellosis in both humans and food animal production, especially poultry. Epidemiological surveillance systems and monitoring programs for Salmonella infections are essential requirements to provide data useful for the effective detection and control of Salmonella outbreaks. The present review will supply a perspective on NTS infection, pathogenesis and antimicrobial resistance with a focus on the epidemiology of salmonellosis in Algeria.

Vancomycin-resistant Enterococcus faecium high-resolution typing by core genome multilocus sequence typing

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Camellia sinensis Mediated Enhancement of Humoral Immunity to Particulate and Non-particulate Antigens

The most common drinking beverage in large portion of the world is Camellia sinensis (green tea). In the present study, we evaluated the adjuvant effect of green tea and tea polyphenols to particulate and non-particulate antigens. BALB/c mice were immunized with particulate and non-particulate antigens. Modulation of immunoglobulin-secreting splenocytes, IgG-mediated and IgM-mediated immunity, was evaluated by hemolytic plaque assay and enzyme-linked immunosorbent assay, respectively. Dose-dependent response of tea polyphenols was also assayed. Phenolic content was measured in crude preparations of green tea. We observed a stimulatory effect of green tea preparations on humoral immune response mediated by the increased number of antibody-secreted cells in spleen. A significant increase in IgM-mediated and IgG-mediated immune response to non-particulate antigen was also observed in green tea-treated animals. A dose-dependent adjuvant effect was seen in the case of tea polyphenols for a longer period of time compared with crude tea preparations. This study indicates polyphenols as major constituents responsible for the enhanced and sustained adjuvant activity of green tea. We suggest that tea polyphenols might be considered for real-life evaluation during adjuvant-mediated vaccination trial programs.

Antibiotic resistance determinants and genetic analysis of Salmonella enterica isolated from food in Morocco

Antimicrobial-resistant non-typhoidal Salmonella (NTS) are an important cause of infection in Africa, but there is a lack of information on their molecular mechanisms of resistance and epidemiology. This study contributes to fill this gap through the characterization by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), plasmid profiling and analysis of antibiotic-resistance determinants of 94 Salmonella enterica strains isolated from food in Morocco. PFGE revealed considerable heterogeneity among the strains, showing 32 pulsotypes. MLST of strains representative of the different serovars evidenced 13 sequence types (STs), three of which were newly identified (ST1694, ST1768 and ST1818) and nine not previously reported in Morocco. Thirty-four strains harbored from one to four plasmids, of IncI1 group in S. Mbandaka, IncFIIA in S. Typhimurium, IncL/M in S. Hadar and S. Blockley. For the first time in Morocco an intact Salmonella Genomic Island 1 (SGI1) carrying the resistance genes aadA2, floR, tetG, blaPSE-1 and sul1 was detected in S. Typhimurium DT104. In serovar Hadar resistance to ampicillin, tetracycline and streptomycin was associated to blaTEM-1, tetA and strA genes respectively, whereas one mutation in gyrA (Asp87Asn) and one in parC (Thr54Ser) genes conferred resistance to nalidixic acid. These findings improve the information on foodborne Salmonella in Morocco, evidencing the presence of MDR strains potentially dangerous to humans, and provide useful data for future studies.

Fasciolopsis buski infection in a Vietnamese pregnant woman with systemic lupus erythematosus

A clinical case of infection caused by Fasciolopsis buski in a 24 weeks pregnant woman from Vietnam affected by systemic lupus erythematosus (SLE) is reported here. On 22 February 2012 the patient was admitted to Hue Hospital in Hue, Vietnam, with a diagnosis of general illness and suspected acute anaemia. Laboratory analysis indicated possible SLE syndrome and coprological tests demonstrated the presence of F. buski eggs. During hospitalization the patient naturally eliminated the adult form in faeces suggesting the infection had already progressed at least for three months. One month after hospitalization due to the high severity of both SLE and fasciolopsiasis, a medical abortion was carried out and the following day the patient died. Even though infection due to Fasciolopsis buski is rare, this case highlights the importance of an accurate and prompt diagnosis of this infectious agent, which may have saved the foetus and mother’s lives.

Antimicrobial resistance in Helicobacter pylori: current situation and management strategy in Vietnam

Increasing antimicrobial resistance to key antibiotics in Helicobacter pylori has become a main cause of treatment failures in many countries, including Vietnam. For this reason it is advisable to perform antimicrobial sensitivity tests to provide more focused regimens for H. pylori eradication. However, this approach is generally unavailable for H. pylori in Vietnam and the selection of treatment regimens is mainly based on the trend of antibiotic use in the population, resistance development in the region, and history of H. pylori eradication of patients. The aim of this review is to examine the current situation of antimicrobial resistance in Vietnam and suggest management strategies for treatment selection.

Genetic determinants of pathogenicity of Escherichia coli isolated from children with acute diarrhea in Maputo, Mozambique

INTRODUCTION

Diarrheagenic Escherichia coli (DEC) represents one of the leading cause of diarrhoea in developing countries. In this study a molecular approach was applied for the detection of diarrheagenic Escherichia coli (DEC) circulating in Maputo, Mozambique.

METHODOLOGY

All isolates were PCR tested for species-specific genes and for 11 molecular markers: stx1, stx2, eae, bfpA, lt, st, ipaH, aap, aggR CVD432 and daaE.

RESULTS

Of the 80 E. coli isolated, 74% were potential DEC: 21% EIEC, 19% EPEC, 15% EAEC, 13% ETEC, 5% DAEC and 1% hybrids.

CONCLISION

This study revealed the complexity of the etiology of diarrhea caused by pathogenic E. coli in Mozambique, and the risk of the emergence of new pathogenic variants due to the horizontal transmission of pathogenicity factors.

Synergistic antimicrobial activity of Camellia sinensis and Juglans regia against multidrug-resistant bacteria

Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR) bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, was tested against Camellia sinensis and Juglans regia extracts. Minimum inhibitory concentrations (MICs) were determined by agar dilution and microbroth dilution assays. Plant extracts were tested for synergistic antimicrobial activity with different antimicrobial agents by checkerboard titration, Etest/agar incorporation assays, and time kill kinetics. Extract treated and untreated bacteria were subjected to transmission electron microscopy to see the effect on bacterial cell morphology. Camellia sinensis extract showed higher antibacterial activity against MDR S. Typhi, alone and in combination with nalidixic acid, than to susceptible isolates." We further explore anti-staphylococcal activity of Juglans regia that lead to the changes in bacterial cell morphology indicating the cell wall of Gram-positive bacteria as possible target of action. The synergistic combination of Juglans regia and oxacillin reverted oxacillin resistance of methicillin resistant Staphylococcus aureus (MRSA) strains in vitro. This study provides novel information about antimicrobial and synergistic activity of Camellia sinensis and Juglans regia against MDR pathogens.

High rate of levofloxacin resistance in a background of clarithromycin- and metronidazole-resistant Helicobacter pylori in Vietnam

Antimicrobial resistance in Helicobacter pylori has increased worldwide and has become a major cause of treatment failure in many countries, including Vietnam. It is advisable to perform an antibiogram to provide optimal regimens for H. pylori eradication. This study evaluated the rate of antibiotic resistance to the four commonly used antibiotics against H. pylori at a tertiary care hospital in Central Vietnam and analysed point mutations in genes related to clarithromycin (CLA) and levofloxacin (LFX) resistance. A total of 92 H. pylori strains from gastric biopsy specimens were tested; 42.4% were resistant to CLA (primary, 34.2%; secondary, 73.7%), 41.3% to LFX (primary, 35.6%; secondary, 63.2%), 76.1% to metronidazole (MTZ) and 1.1% to amoxicillin. Multidrug resistance was observed in 56.5% (primary, 50.7%; secondary, 78.9%) of isolates (P<0.05). The rate of resistance to LFX was significantly higher in females than males (P<0.05). Most of the CLA- and LFX-resistant strains harboured resistance-associated mutations, with common positions at A2143G and T2182C in the 23S rRNA gene and at Asn-87 or Asp-91 in GyrA. Minimum inhibitory concentrations (MICs) increased in strains carrying quadruple mutations in their 23S rRNA gene and in strains with Asn-87 GyrA mutation (P<0.05). One high-level LFX-resistant strain (MIC=32mg/L) had new mutations with a combination of N87A, A88N and V65I. High resistance rates to CLA, MTZ and LFX discourage standard and LFX-based triple therapies as first-line treatment in Vietnam.

Diversity among human non-typhoidal salmonellae isolates from Zimbabwe

BACKGROUND

Non-typhoidal Salmonella infections are an important public health problem in sub-Saharan Africa, especially among children and HIV-seropositive patients in whom they may cause invasive disease.

METHODS

In order to better understand the epidemiology of Salmonella infections in southern Africa we typed, using serotyping, phage typing and multilocus sequence typing, 167 non-typhoidal Salmonella strains isolated from human clinical specimens during 1995-2000.

RESULTS

The most common serovars were Salmonella Typhimurium DT56/ST313, Salmonella Enteritidis PT4 and Salmonella Isangi ST216. Isolates of Salmonella Isangi showed a multidrug-resistant phenotype that was resistant to extended-spectrum cephalosporins. Twelve new sequence types and six new serotypes of Salmonella were identified.

CONCLUSIONS

Given the diversity detected in the study it seems likely that many new variants of S. enterica are extant in Zimbabwe and by implication across sub-Saharan Africa. We have demonstrated the presence in Zimbabwe of a multidrug-resistant strain of the serovar Salmonella Isangi and demonstrated the diversity of Salmonella circulating in one sub-Saharan African country. Further studies on the characteristics of Salmonella Isangi isolates from Zimbabwe, including plasmid typing and genotyping, are essential if effective control of the spread of this potential pathogen in sub-Saharan Africa is to be achieved.

Prevalence, diversity and disease association of Helicobacter pylori in dyspeptic patients from Pakistan

Introduction: The etiological association of Helicobacter pylori with gastric ulcer (GU), gastric cancer (GC), and duodenal ulcer (DU) is well-known. Understanding the epidemiology of H. pylori facilitates the estimation of disease burden in a certain population. This study presents the diversity of H. pylori genotypes and their association with different clinical outcomes among dyspeptic patients in Pakistan over a period of four years. Methodology: Gastric biopsy samples from a total of 450 dyspeptic individualswere subjected to PCR, genotypingand histology. Results: A total of 201 (45%) cases were found positive for H. pylori. The detection rate was high in GU (91%), DU (86%) and GC (83%) cases compared with those cases who had intact gastric mucosa (18%). Histology revealed the presence of infection in 68% of cases of mild/chronic nonspecific gastritis with others belonging to the GU sequel. cagA gene carriage was observed in 104 (51%) cases or mostly from DU, GU and GC groups, of which 97 were Western type strains while 3 were East-Asian type strains that are rarely observed in South Asia. vacA allelic variant s1am1 was most commonly observed, followed by s1am2, and s1bm1, with direct correlation in diseased cases (gastritis, GU, DU and GC). Prevalent genotypic combinations were s1am1/cagA- in gastritis and s1am1/cagA+ in DU, GU, and GC. Conclusions: Our study indicates the predominant circulation of Western type cagA and vacAs1am1 type H. pylori strains in Pakistan.

Influenza monitoring in Sardinia, Italy identifies H3 subtype in Mediterranean wild migratory birds

INTRODUCTION

Wild migratory birds are global distributors of pathogens. Sardinia, Italy, is the second largest Island in the Mediterranean and is a land bridge between Europe and Africa.

METHODOLOGY

We designed a surveillance protocol to investigate wild migratory birds for presence, frequency, and type of avian influenza viruses. We collected over 4,000 avian samples and compared three sampling methods, fecal, cloacal, and tracheal, to determine the most productive for virus identification. To determine frequency of infection, RNA was extracted and RT-PCRs for avian influenza virus genes were run. Positive samples were cultivated for live virus, sub typed and sequenced.

RESULTS

Forty-four samples were positive for influenza nucleoprotein gene. We identified two previously unidentified H3 subtype strains and found cloacae to have the highest rate of virus identification and fecal sampling to provide quality RNA and repeatable results for determination of virus presence.

CONCLUSION

Our investigation provides information on the frequency of Mediterranean avian influenza viruses, and validates the initiation of an avian influenza surveillance protocol.  Taken together with global avian influenza findings, these results give insight into infectious disease distributions which is important for viral pandemic monitoring and design of preventative measures.

Intra- and inter-laboratory evaluation of an improved multiplex-PCR method for detection and typing of Salmonella

INTRODUCTION

We developed and evaluated a multiplex-PCR method for rapid detection of the most common Salmonella serovars in both developed and developing countries. Additionally, the stability of the premixed reagents at high room temperature was studied.

METHODOLOGY

Fifty-two Salmonella strains belonging to the collections of the University of Sassari, Italy, and to the University of the Basque Country, Spain, and a collection of a hundred blinded strains, were used to evaluate the multiplex-PCR. Primers targeting genes STY1599 and fliC were selected, and the method was evaluated both intra and inter-laboratories.

RESULTS

The inter-laboratory reproducibility was 95.92%, with a kappa index of 0.757 that indicates a substantial agreement and a high accuracy (80.81%). The sensitivity, specificity, accuracy and precision indexes for the Salmonella genus and S. Typhi targets were maximum, although the targets for Paratyphi A, Typhimurium and Enteritidis showed less accuracy. During a seven-week period, hot-start multiplex-PCR runs were performed with reagents mixed with wax to test their stability at 30ºC, and no significant variation in the patterns of amplification was observed.

CONCLUSIONS

An improved multiplex-PCR for rapid detection of the most common serovars of Salmonella operable in both developed and developing countries has been designed and tested intra and inter-laboratories. Following a careful optimization protocol will not only allow the confirmation of any suspicious colony by the amplification of the Salmonella genus target, but also the preliminary adscription to the prevalent serovars. Premixed reagents with wax facilitate the throughput and stability of reagents at high room temperatures.

Prune melanoidins protect against oxidative stress and endothelial cell death

The health-promoting effects of fruit and vegetable consumption are thought to be due to phytochemicals contained in fresh plant material. Whether processed plant foods provide the same benefits as unprocessed ones is an open question. Melanoidins from heat-processed plums (prunes) were isolated and their presence confirmed by hydroxymethylfurfural content and browning index. Oxidative-induced endothelial cell (EC) damage is the trigger for the development of cardiovascular diseases (CVD); therefore the potential protective effect of prune melanoidins on hydrogen peroxide-induced oxidative cell damage was investigated on human endothelial ECV304 cells. Cytoplasmic and mitochondrial redox status was assessed by using the novel, redox-sensitive, ratiometric fluorescent protein sensor (roGFP), while mitochondrial membrane potential (MMP) was investigated with the fluorescent dye, JC-1. Treatment of ECV304 cells with hydrogen peroxide dose-dependently induced both mitochondrial and cytoplasmic oxidation, in addition to MMP dissipation, with ensuing cell death. Pretreatment of ECV304 with prune melanoidins, significantly counteracted and ultimately abolished hydrogen peroxide elicited phenomena, clearly indicating that these polymers protect human EC against oxidative stress.

Bacteraemia with pleural effusions complicating typhoid fever caused by high-level ciprofloxacin-resistant Salmonella enterica serotype Typhi

An unusual case of bacteraemia with bilateral pleural effusion caused by Salmonella enterica serotype Typhi in a 10-year-old previously healthy girl is reported. The organism was isolated from pleural fluid aspirate and from blood, and exhibited high-level ciprofloxacin resistance (MIC 16 μg/ml) associated with triple mutations in the QRDRs of the gyrA and parC genes leading to the amino-acid changes Ser83→Phe and Asp87→Asn in gyrA and Ser80→Ile in parC. The patient was successfully treated with parenteral ceftriaxone and intercostal chest tube drainage. The case is notable because of the important issue of antimicrobial resistance in S. Typhi and the therapeutic dilemma faced by clinicians regarding the empirical use of ciprofloxacin and newer fluoroquinolones.

Prevalence and antibiotic-resistance of Salmonella isolated from food in Morocco

BACKGROUND

Salmonellosis remains one of the most frequent food-borne diseases worldwide, especially in developing countries. The emergence of antimicrobial resistance in Salmonella isolates from food can potentially compromise the treatment of these infections. This investigation was conducted for the first time in Morocco both to detect the occurrence of Salmonella in foods as well as to determine the antibiotic resistance profile of the Salmonella isolates.

METHODOLOGY

In total, 11,516 food samples collected from 2002 to 2005 were investigated. Isolated Salmonella were characterized by serotyping and susceptibilities were determined for 15 antimicrobial drugs using the disc diffusion assay.

RESULTS

The overall percentage of Salmonella prevalence (n=105) was 0.91% with rates of 71% for slaughterhouses and 9% for seafood. Sixteen different serotypes were identified among 104 Salmonella enterica isolates including serotypes Infantis (n=25), Bredeney (n=13), Blokley (n=11), Typhimurium (n=9), Mbandaka (n=8), Branderup II (n=7), and Kiambu (n=6); 1 isolate of Salmonella enterica belonged to subspecies II salamae. Twenty-nine percent of isolates (n=30/105) were resistant to at least one antimicrobial. Resistance to tetracycline was the most common finding (21%), followed by resistance to ampicillin (13%), amoxicillin+clavulanic acid (9%), streptomycin (7%), chloramphenicol (4%) and nalidixic acid (3,8%). None of the isolates was resistant to 3rd-cephalosporin and fluoroquinolones (i.e. ciprofloxacin). Multidrug resistance (MDR) was seen in 9.5% of the isolates, mainly in S.. Typhimurium DT104 with R-type ACSSuT and S. Hadar.

CONCLUSIONS

Despite a low frequency of Salmonella isolation, S. Typhimurium DT104 was identified in the first step of the food chain. The study points out the need control antibiotic resistance in Salmonella isolated from food in Morocco to avoid the spread of MDR.

Emergence of plasmid-mediated multidrug resistance in epidemic and non-epidemic strains of Salmonella enterica serotype Typhi from Jordan

BACKGROUND

Enteric fever caused by Salmonella enterica serovar Typhi has not been adequately explored in Jordan.

METHODOLOGY

In this study we investigated antibiotic resistance patterns and resistance determinants coupled with fingerprint methods of forty-eight isolates of S. Typhi obtained from 113 patients with suspected enteric fever admitted at six governmental hospitals in different directorates in Jordan. Twenty-four isolates were from an outbreak of typhoid fever that occurred between October 2004 and January 2005, and another twenty-four were from sporadic cases from 2005.

RESULTS

All isolates of S. Typhi were resistant to streptomycin. A multidrug resistant (MDR) pattern of ampicillin, chloramphenicol, co-trimoxazole with tetracycline and streptomycin (R-type ACCoTS) was found in 58% of the epidemic strains causing the outbreak and in 98% of the strains from sporadic cases. MDR isolates harbored a single IncHI1 plasmid containing a class 1 integron (dfrA7). Plasmid conjugation studies demonstrated a genetic transfer of resistance (ACCoT). S. Typhi isolates were all sensitive to fluoroquinolones and cefotaxime, the alternative drugs recommended for treatment of typhoid fever. The genomic analysis using PFGE showed: a) the outbreak was caused by an introduced circulating clone with/without an MDR plasmid, and b) isolates from the sporadic cases from 2005 are the same MDR clone that persisted and spread in the country.

CONCLUSION

The emergence of MDR S. Typhi strains is a majorn important public health issue in Jordan. This study should guide selection of effective antibiotic therapy for the treatment of typhoid and monitoring of the spread of MDR of S. Typhi.

[1,2,3]Triazolo[4,5-h]quinolones. A new class of potent antitubercular agents against multidrug resistant Mycobacterium tuberculosis strains

In this preliminary study we report the activity of 3-methyl-9-substituted-6-oxo-6,9-dihydro-3H-[1,2,3]-triazolo[4,5-h]quinolone-carboxylic acids and their esters as a new class of antiinfective agents against MDR Mycobacterium tuberculosis. In antitubercular screening against H37Rv and 11 clinically isolated strains of M. tuberculosis several derivatives (1o,3a,c,i,j,p) showed MIC(90) in the range 0.5-3.2 microg/mL. 3c showed no cytotoxicity and proved to be the most potent derivative exhibiting MIC(90)=0.5 microg/mL against all M. tuberculosis strains and infected human macrophages (J774-A1) tested.

Molecular characterization of ciprofloxacin-resistant Salmonella enterica serovar Typhi and Paratyphi A causing enteric fever in India

OBJECTIVES

To define the genetic characteristics and resistance mechanisms of clinical isolates of Salmonella enterica serovar Typhi (S. Typhi) and S. enterica serovar Paratyphi A (S. Paratyphi A) exhibiting high-level fluoroquinolones resistance.

METHODS

Three S. Typhi and two S. Paratyphi A ciprofloxacin-resistant isolates (MICs > 4 mg/L) were compared with isolates with reduced susceptibility to ciprofloxacin (MICs 0.125-1 mg/L) by PFGE, plasmid analysis, presence of integrons and nucleotide changes in topoisomerase genes.

RESULTS

In S. Typhi and Paratyphi A, a single gyrA mutation (Ser-83-->Phe or Ser-83-->Tyr) was associated with reduced susceptibility to ciprofloxacin (MICs 0.125-1 mg/L); an additional mutation in parC (Ser-80-->Ile, Ser-80-->Arg, Asp-69-->Glu or Gly-78-->Asp) was accompanied by an increase in ciprofloxacin MIC (> or = 0.5 mg/L). Three mutations conferred ciprofloxacin resistance: two in gyrA (Ser-83-->Phe and Asp-87-->Asn or Asp-87-->Gly) and one in parC. This is the first report of parC mutations in S. Typhi. Ciprofloxacin-resistant S. Typhi and S. Paratyphi A differed in their MICs and mutations in gyrA and parC. Moreover S. Typhi harboured a 50 kb transferable plasmid carrying a class 1 integron (dfrA15/aadA1) that confers resistance to co-trimoxazole and tetracycline but not to ciprofloxacin. PFGE revealed undistinguishable XbaI fragment patterns in ciprofloxacin-resistant S. Typhi as well as in S. Paratyphi A isolates and showed that ciprofloxacin-resistant S. Typhi have emerged from a clonally related isolate with reduced susceptibility to ciprofloxacin after sequential acquisition of a second mutation in gyrA.

CONCLUSIONS

To our knowledge this is the first report of molecular characterization of S. Typhi with full resistance to ciprofloxacin. Notably, the presence of a plasmid-borne integron in ciprofloxacin-resistant S. Typhi may lead to a situation of untreatable enteric fever.

Role of the Salmonella abortusovis virulence plasmid in the infection of BALB/c mice

Following oral inoculation of BALB/c mice, Salmonella abortusovis strain SS44 was recovered in lower numbers from the Peyer's patches and mesenteric lymph nodes compared with S. typhimurium strain SL1344, whereas splenic infections were equivalent between the two serovars. SS44 was cured of its virulence plasmid or subjected to mutagenesis of the spv genes, and the Spv(-) derivatives were tested for virulence in mice. Plasmid-cured S. abortusovis SU40 retained virulence in BALB/c mice when inoculated intraperitoneally. On the other hand, mice infected orally with SU40 had greatly reduced splenic infection compared to those infected with wild-type SS44. Similar results were obtained after Tn5 insertion mutagenesis of the spvR gene or deletion of the spvABCD locus. These results suggest that in the gut-associated lymphoid tissues S. abortusovis may replicate less than S. typhimurium and that the S. abortusovis virulence plasmid primarily affects systemic infection after oral inoculation but not after intraperitoneal administration in the mouse model.

IS200 fingerprint of Salmonella enterica serotype Typhimurium human strains isolated in Sardinia

A collection of Salmonella enterica serotype Typhimurium human strains isolated in Northern Sardinia (Italy) was examined for the insertion sequence IS200, phage type, antibiotic profile, ribotyping polymorphisms and plasmid profile. All clinical isolates studied contained from 4 to 10 copies of the IS200 element. IS200 permitted to discriminate Typhimurium strains and to identify five IS200 types, some of them circulating in Sardinia at least since 1900. Strains belonging to phage DT104 predominated and correlated with a specific IS200 pattern.

Conventional and molecular approaches to isolates of Salmonella hadar from sporadic and epidemic cases

In September 1994 an outbreak of gastroenteritis occurred in 437 people who had consumed lunch in the canteen of a factory in Central Italy. Salmonella sp. was isolated from stools of 99 patients and in 73 of them Salmonella hadar was identified. This is the first outbreak caused by this serotype described in Italy. In order to examine the genotypic basis of the epidemic strains, molecular typing was applied to sporadic strains isolated before and after the outbreak episode. For this purpose phage type, resistance to antibiotics, DNA plasmid profile and sites of insertion of the mobile element of IS200 were determined. The epidemic strains were genetically distinct from the non-epidemic isolates; they were shown to be phage type 26, harbouring four small plasmids, were resistant to nalidixic acid and showed a unique characteristic IS200 fingerprint. The typing methods used in this study allowed the identification and discrimination of the outbreak strains from related isolates. They can thus be considered as a tool for epidemiological purposes. In addition we should point out the emerging resistance to nalidixic acid, largely used in veterinary medicine, in Salm. hadar.