Added diagnostic value and impact on antimicrobial therapy of 16S rRNA PCR and amplicon sequencing on resected heart valves in infective endocarditis: a prospective cohort study.

OBJECTIVES: For adequate management and therapy of infective endocarditis (IE), identification of the causative pathogen is crucial but molecular testing results are not currently included in diagnostic criteria. The added diagnostic value and impact on antimicrobial therapy of 16S rRNA PCR and amplicon sequencing (16S rRNA PCR) performed on excised heart valves from patients with IE was evaluated alongside the effect of pre-operative antibiotics on the performance of blood culture (BC), valve culture (VC) and 16S rRNA PCR. METHODS: All patients undergoing valve surgery for definite or possible IE, according to modified Duke Criteria, were prospectively included from July 2013 up to and including June 2016. RESULTS: In all, 127 patients were included. Sensitivity for detecting the causative micro-organism in 120 post-operative definite IE patients was 26% for VC and 87% for BC and 16S rRNA PCR. 16S rRNA PCR, VC and BC were equally sensitive for different valve types and causative pathogens. In 27 (21%) definite IE patients, 16S rRNA PCR clarified discrepant culture results or was the only method identifying the causative pathogen. In 12 (10%) post-operative definite IE cases, molecular testing results influenced antimicrobial therapy. CONCLUSIONS: The very good performance characteristics, added diagnostic value and impact on antimicrobial therapy of molecular testing of heart valves should support the incorporation of molecular testing in diagnostic criteria and guidelines for IE.

Prevalence and distribution of beta-lactamase coding genes in third-generation cephalosporin-resistant Enterobacteriaceae from bloodstream infections in Cambodia.

Resistance to third-generation cephalosporins in Gram-negative bacteria is emerging in Asia. We report the prevalence and distribution of extended-spectrum beta-lactamase (ESBL), AmpC beta-lactamase and carbapenemase-coding genes in cefotaxime-resistant Enterobacteriaceae isolates from bloodstream infections (BSI) in Cambodia. All Enterobacteriaceae isolated from BSI in adult patients at Sihanouk Hospital Centre of HOPE, Phnom Penh, Cambodia (2007-2010) were assessed. Antimicrobial susceptibility testing was carried out by disc diffusion and MicroScan according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Screening for ESBL, plasmidic AmpC and carbapenemase-coding genes was performed by multiplex polymerase chain reaction (PCR) sequencing assays. Identification of the ST131 clone was performed in all CTX-M-positive Escherichia coli, using PCR targeting the papB gene. Out of 183 Enterobacteriaceae, 91 (49.7 %) isolates (84 BSI episodes) were cefotaxime-resistant: E. coli (n = 68), Klebsiella pneumoniae (n = 17) and Enterobacter spp. (n = 6). Most episodes were community-acquired (66/84; 78.3 %). ESBLs were present in 89/91 (97.8 %) cefotaxime-resistant isolates: 86 (96.6 %) were CTX-M, mainly CTX-M-15 (n = 41) and CTX-M-14 (n = 21). CTX-M of group 1 were frequently associated with TEM and/or OXA-1/30 coding genes and with phenotypic combined resistance to ciprofloxacin, sulphamethoxazole-trimethoprim and gentamicin (39/50, 78.0 %). Plasmidic AmpC (CMY-2 and DHA-1 types) were found alone (n = 2) or in combination with ESBL (n = 4). Eighteen E. coli isolates were identified as B2-ST131-O25B: 11 (61.1 %) carried CTX-M-14. No carbapenemase-coding genes were detected. ESBL among Enterobacteriaceae from BSI in Cambodia is common, mainly associated with CTX-M-15 and CTX-M-14. These findings warrant urgent action for the containment of antibiotic resistance in Cambodia.

Laboratory diagnosis of schistosomiasis and Katayama syndrome in returning travellers.

The gold standard for laboratory diagnosis of schistosomiasis is the presence of typical eggs in stool or urine. The laboratory diagnosis of schistosomiasis and Katayama syndrome in returning travellers is difficult because the number of excreted eggs is often very limited. In early infections and in patients with only a few contacts with contaminated water, the total number of parasites, migrating larvae or schistosomulae, and adult worms, is very low. Eggs can only be found in faeces or urine when there is at least one pair of adult worms at the final location. The number of parasites increases as a function of the number of contacts with infected water. The exact latency between contamination and egg production is unknown. It is estimated that excretion of eggs starts after 40-50 days. The specific diagnosis of early schistosomiasis and Katayama fever relies essentially on serologic tests or preferably on PCR (if available). These assays are much more sensitive (up to four times) in the early phase of schistosomiasis than microscopic examination for typical eggs. Eosinophilia (sometimes exceeding 50%) is often present in patients with acute schistosomiasis (Katayama fever), but may be limited or absent in late fibrotic manifestations of the disease.

The aetiology and antibiotic management of community-acquired pneumonia in adults in Europe: a literature review.

The purpose of this paper was to generate up-to-date information on the aetiology of community-acquired pneumonia (CAP) and its antibiotic management in adults across Europe. Structured searches of PubMed identified information on the aetiology of CAP and its antibiotic management in individuals aged >15 years across Europe. We summarise the data from 33 studies published between January 2005 and July 2012 that reported on the pathogens identified in patients with CAP and antibiotic treatment in patients with CAP. Streptococcus pneumoniae was the most commonly isolated pathogen in patients with CAP and was identified in 12.0-85.0 % of patients. Other frequently identified pathogens found to cause CAP were Haemophilus influenzae, Gram-negative enteric bacilli, respiratory viruses and Mycoplasma pneumoniae. We found several age-related trends: S. pneumoniae, H. influenzae and respiratory viruses were more frequent in elderly patients aged ≥65 years, whereas M. pneumoniae was more frequent in those aged <65 years. Antibiotic monotherapy was more frequent than combination therapy, and beta-lactams were the most commonly prescribed antibiotics. Hospitalised patients were more likely than outpatients to receive combination antibiotic therapy. Limited data on antibiotic resistance were available in the studies. Penicillin resistance of S. pneumoniae was reported in 8.4-20.7 % of isolates and erythromycin resistance was reported in 14.7-17.1 % of isolates. Understanding the aetiology of CAP and the changing pattern of antibiotic resistance in Europe, together with an increased awareness of the risk factors for CAP, will help clinicians to identify those patients most at risk of developing CAP and provide guidance on the most appropriate treatment.

Stimulation of the i.v. to oral switch of bioavailable drugs by phone calls in a Belgian tertiary care hospital.

INTRODUCTION: Early switch from intravenous to oral administration of drugs with an almost complete oral bioavailability, can have important benefits. Drugs with almost complete bioavailability, like clindamycin (Dalacin), levofloxacin (Tavanic) and paracetamol (Perfusalgan/Dafalgan), are very suitable for an early intravenous to oral switch in patients whose gastrointestinal absorption is intact. The aim of this study was to investigate the impact of direct phone contact between pharmacist and clinician on the intravenous to oral switch and to evaluate the reasons, mentioned by clinicians, that prevented an early switch. MATERIALS & METHODS: The project was initiated in a Belgian 1900-bed tertiary care hospital with a poster, communicated through the hospital's intranet and spread to every hospital ward. During one month, all prescriptions for intravenous clindamycin, levofloxacin and paracetamol were evaluated. The treating clinician was contacted by phone to evaluate if an intravenous to oral switch was possible. RESULTS: Clinicians were contacted concerning 377 patients. For 58.7% of patients, the switch from intravenous to oral administration was made. In case of refusal, several reasons were mentioned by the clinician, some more appropriate than others. CONCLUSION: Despite several appropriate reasons preventing an early intravenous to oral switch, there are still some aberrant opinions circulating in the hospital environment. Active interventions of pharmacists to stimulate intravenous to oral switch, using phone contact with the treating clinicians, can possibly be an adequate technique to stimulate intravenous to oral switch, but this needs to be further optimized.

Comparing normal saline versus diluted heparin to lock non-valved totally implantable venous access devices in cancer patients: a randomised, non-inferiority, open trial.

BACKGROUND: Heparin has been used for years as a locking solution in totally implantable venous access devices. Normal saline (NS) might be a safe alternative for heparin. However, evidence of non-inferiority of NS versus heparin is lacking. PATIENTS AND METHODS: We randomly allocated 802 cancer patients with a newly inserted port either to heparin lock (300 U/3 ml) or to NS lock groups in a 1:1 assignment ratio. The primary outcome was the number of functional complications, which was defined as 'easy injection, impossible aspiration' at port access. Secondary outcomes included all functional problems and catheter-related bacteraemia. We hypothesised that NS locks do not cause more functional problems and catheter-related bacteraemia than heparin locks. Non-inferiority is established if the upper limit of the confidence interval (CI) for the relative risk of NS versus heparin is <1.4. RESULTS: Three hundred and eighty-two patients from the NS group and 383 from the heparin lock group were included in the analysis. The incidence rate of our primary outcome (easy injection, impossible aspiration) was 3.70% (95% CI 2.91%-4.69%) and 3.92% (95% CI 3.09%-4.96%) of accesses in the NS and heparin groups, respectively. The relative risk was 0.94% (95% CI 0.67%-1.32%). Catheter-related bloodstream infection was 0.03 per 1000 catheter days in the NS group and 0.10 per 1000 catheter days in the heparin group. CONCLUSION: NS is a safe and effective locking solution in implantable ports if combined with a strict protocol for device insertion and maintenance.

Fever in HIV-infected patients: less frequent but still complex.

Fever was a common symptom in patients with Human Immunodeficiency Virus (HIV) infection in the early phases of the epidemic. Fever of Unknown Origin (FUO) was frequent in HIV-patients and conditions causing FUO were often opportunistic conditions. The HIV-epidemic continues to expand, but access to effective antiretroviral therapy is also expanding, resulting in a growing number of HIV-infected patients less likely to be severely immunocompromised and less likely to present opportunistic conditions. Yet part of newly diagnosed patients continue to present with advanced HIV-infection and are still at high risk of opportunistic conditions. This epidemiological evolution strongly influences the spectrum of conditions causing fever and FUO in HIV-patients. While some patients with HIV-associated fever and FUO may still be suffering from opportunistic conditions classically associated with HIV-related FUO, many others will have causes of fever that are similar to the non-HIV-infected population or to classical FUO. Strategies for diagnosis and treatment of fever and its causes in HIV-infected patients need to take into account this evolution.

Inhibition of staphylothrombin by dabigatran reduces Staphylococcus aureus virulence.

BACKGROUND: Staphylocoagulase and von Willebrand binding protein (VWbp) bind to prothrombin to form the staphylothrombin complex that converts fibrinogen into fibrin. OBJECTIVES: To study the role of staphylothrombin and its inhibition by dabigatran on Staphylococcus aureus virulence. METHODS: We studied the effect of staphylothrombin inhibition on bacterial attachment to polystyrene surfaces, leukocyte activation and bactericidal activity for S. aureus ATCC 25923, S. aureus Newman, and staphylocoagulase- and VWbp-negative S. aureus Newman mutants in the presence or absence of prothrombin and fibrinogen. We measured the abscess size after subcutaneous (s.c.) injection of S. aureus ATCC 25923 and S. aureus Newman, as well as an S. aureus Newman mutant strain lacking staphylocoagulase and VWbp, in mice treated with either dabigatran or placebo. RESULTS: Staphylothrombin-mediated fibrin increased the association of S. aureus to polystyrene surfaces and reduced the bactericidal activity of leukocytes. The absence or inhibition of staphylothrombin decreased the bacterial association, enhanced leukocyte activation and reduced bacterial survival in vitro. Abscess size was smaller in mice treated with dabigatran or infected with a coagulase-negative mutant. CONCLUSION: Inhibition or the absence of staphylothrombin reduced S. aureus virulence in in vitro and in vivo models.

Long-term treatment of refractory invasive fungal infection with posaconazole: additive value of therapeutic drug monitoring.

Posaconazole is a recently developed broad-spectrum triazole antifungal with potential for long-term prophylaxis or therapy of invasive fungal infections. This case illustrates the additive value for therapeutic drug monitoring to guide clinical decision-making in high risk patients.

Clinical evaluation of the Copan ESwab for methicillin-resistant Staphylococcus aureus detection and culture of wounds.

The screening for and diagnosis of bacteriological infections often involves the collection and transportation of swab samples. The Copan ESwab was compared with the dry cotton Copan swab for methicillin-resistant Staphylococcus aureus (MRSA) screening (n = 200 paired samples) and with the Amies agar gel swab (Copan) for the sampling of burn and orthopaedic wounds (n = 203 paired samples) in terms of Gram staining and bacterial recovery. Gram stains performed with ESwab liquid showed significantly more Gram-negative rods, streptococci, Gram-positive cocci, Gram-positive rods, polymorphonuclear cells, lymphocytes and red blood cells than Gram stains from dry swabs. Bacterial recovery was significantly higher with ESwab (p < 0.01, for both MRSA screening and wounds, quantitative/semi-quantitative method). This lead to a slightly higher detection rate of MRSA (128 vs. 124 MRSA-positive ESwabs and dry swabs, respectively, p = 0.50) and a higher detection rate of coagulase-negative Staphylococcus spp. (44 isolates with ESwab vs. 29 with Amies gel swab, p = 0.001) and Enterococcus spp. (15 isolates with ESwab vs. 7 isolates with Amies gel swab, p = 0.005) with ESwab (quantitative method). We confirmed that ESwab has a high performance for Gram stains and a higher bacterial recovery than dry and Amies gel swabs when using clinical samples for MRSA screening and wound sampling.

Treatment of mycotic aneurysms with involvement of the abdominal aorta: single-centre experience in 44 consecutive cases.

OBJECTIVE: To review our management of mycotic aneurysms involving the abdominal aorta over the past 2 decades to assess the safety and efficacy of in-situ and extra-anatomic repair combined with antibiotic treatment. MATERIALS AND METHODS: From March 1990 to August 2008, 44 patients with a mycotic aneurysm involving the abdominal aorta were treated at our University Hospital. For all patients, we recorded the aetiology, clinical findings and anatomic location of the aneurysm, as well as bacteriology results, surgical and antibiotic therapy and morbidity and mortality. RESULTS: Twenty-one (47.7%) of the mycotic aneurysms had already ruptured at the time of surgery. Free rupture was present in nine patients (20.5%). Contained rupture was observed in 12 patients (27.3%). Urgent surgery was performed in 18 cases (40.9%). Revascularisation was achieved by in-situ reconstruction in 37 patients (84.1%), while extra-anatomic reconstruction was performed in six patients (13.6%). One patient (2.3%) was treated with a combined in-situ and extra-anatomic reconstruction. In one case (2.3%), endovascular aneurysm repair (EVAR) was performed. In-hospital mortality was 22.7%, 50% in the extra-anatomic reconstruction group and 18.9% in the in-situ repair group. One-third (33.3%) of our patients, who presented with a ruptured mycotic aneurysm died in the peri-operative period. This mortality was 13% in the patient-group presenting with an intact aneurysm. Of the 34 surviving patients, 12 patients (27.3% of surviving patients died after discharge from our hospital. In half of these patients, an acute cardiac event was to blame. Three patients (8%) showed re-infection after in-situ reconstruction. CONCLUSION: Management of mycotic aortic aneurysms remains a challenging problem. The results of surgery depend on many factors. In our experience, in-situ repair remains a feasible and safe treatment option for patients who are in good general condition at the time of surgery.

Significance of the isolation of Candida species from airway samples in critically ill patients: a prospective, autopsy study.

PURPOSE: Recovery of Candida from the respiratory tract is common. Large series on the incidence of histologically proven Candida pneumonia in intensive care unit (ICU) patients are lacking. METHODS: A two-year prospective study of all autopsies performed on patients who died in the ICU was conducted. For autopsy-proven cases of Candida pneumonia, we required microscopic demonstration of yeast invasion in lung autopsy specimens that showed inflammation. We looked for differences in incidence in patients with and without respiratory samples positive for Candida species pre-mortem. RESULTS: Of 1,587 patients admitted to the ICU, 301 (19%) died of whom 232 (77%) were autopsied. Of those, 135 patients (58%) had histopathological evidence of pneumonia. A total of 77 cases (57%) with pneumonia at autopsy had positive tracheal aspirate and/or BAL cultures for Candida spp. performed during the preceding two weeks. No cases of Candida pneumonia were identified amongst those 77 cases. In the other 58 patients with autopsy-proven pneumonia and no Candida isolation pre-mortem, no Candida pneumonia was observed either. CONCLUSIONS: Despite frequent isolation of Candida spp. from the airways, over a two-year period no single case of Candida pneumonia was found among the patients with evidence of pneumonia on autopsy. This study indicates that Candida pneumonia is an extremely rare occurrence in ICU patients and provides further evidence against the common use of antifungal therapy triggered by a microbiology report of Candida isolation from the respiratory tract.

Nosocomial infective endocarditis: should the definition be extended to 6 months after discharge.

Because the microbiology and patient population of infective endocarditis (IE) have evolved, the traditional definition of nosocomial IE may require revision. The question of whether this definition should be extended to 6 months after discharge was explored, and a high rate of episodes with nosocomial pathogens (coagulase-negative staphylococci) and a low rate of episodes with community pathogens (streptococci) in the extended nosocomial group were found. Therefore, modification of the traditional definition is proposed, distinguishing between early (as traditionally described) and late nosocomial IE (IE in association with a significant invasive procedure performed during a hospitalization between 8 weeks and 6 months before the onset of symptoms).

Aggressive cutaneous squamous cell carcinoma associated with prolonged voriconazole therapy in a renal transplant patient.

A 69-year-old man, with a history of end-stage renal disease due to polyarteritis nodosa, followed by invasive pulmonary aspergillosis secondary to cyclophosphamide and corticosteroids, received a renal transplant 2 years ago under prophylactic treatment with voriconazole. Because of the severity of the aspergillosis, it was decided to continue voriconazole for a prolonged period. Eighteen months after transplantation, the patient developed a severe facial phototoxic reaction. A few months later, he developed multiple actinic keratoses and a large, rapidly expanding, poorly differentiated squamous cell carcinoma (SCC) with perineural invasion and metastatic lymph nodes, necessitating radical surgery and radiotherapy. Voriconazole therapy has been suggested to be involved in the development of multi-focal invasive SCC when complicated by a phototoxic reaction. Therefore, an alternative antifungal prophylaxis regimen (for instance with posaconazole) should be considered when evaluating patients for solid organ transplantation who are at high risk for the development of cutaneous malignancies.

Methicillin-resistant versus methicillin-sensitive Staphylococcus aureus infective endocarditis.

The incidence of methicillin-resistant Staphylococcus aureus (MRSA) infective endocarditis (IE) is increasing. This study compared clinical characteristics and mortality in patients with methicillin-sensitive S. aureus (MSSA) IE versus MRSA IE, based on a prospectively collected series of 72 consecutive patients with definite S. aureus IE according to the modified Duke criteria between June 2000 and December 2006. Sixteen of 72 IE patients (22%) were caused by MRSA. Nosocomial origin, surgical site infection, surgery in the previous 6 months, the presence of a catheter and persistent bacteremia were significantly associated with MRSA. MSSA patients had significantly more unknown origin of bacteremia and experienced a significantly higher rate of major embolism than MRSA patients. MSSA patients underwent more frequently combined surgical and antimicrobial therapy, and MRSA patients were treated more frequently with antimicrobial therapy due to a contraindication to surgery. The 6-month mortality was higher in patients with MRSA than MSSA. In the MSSA group treated with antimicrobial therapy without an indication to surgery, all patients survived, and in the combined surgical and antimicrobial group 29% died. The mortality in MRSA patients was lowest if combined surgical and antimicrobial therapy was performed. Both in MSSA and MRSA patients with antimicrobial therapy due to a contraindication to surgery, the mortality was extremely high. These data suggest that in S. aureus IE patients with a nosocomial origin, the presence of a catheter or recent surgery, initial therapy should include antimicrobial agents active against MRSA. Antimicrobial therapy alone with close monitoring of the therapeutic effect and signs of complicated course is an acceptable approach in selected patients with MSSA IE. Denial of surgery because of local or general factors in patients that meet criteria for surgical intervention in acute IE is prognostically ominous.

Influenza vaccination is efficacious and safe in renal transplant recipients.

Whether influenza vaccination in solid-organ transplant recipients is efficacious remains a controversial issue. Furthermore, theoretical concerns have been raised regarding the safety of vaccination as it might trigger rejection of the allograft. The present prospective trial is aimed at investigating the antibody response and safety of influenza vaccination in renal transplant recipients (RTR). A total of 165 RTR and 41 healthy volunteers were vaccinated with a standard trivalent inactivated influenza vaccine. Hemagglutination-inhibiting (HI) antibodies were quantified before and 1 month after vaccination. Seroprotection (SP) and seroresponse (SR) were defined as a titer > or =40 and a 4-fold rise in HI titer, respectively. Similar SR rates were observed in both groups. Postvaccination SP rates in RTR amounted to 92.7%, 78.7% and 82.9% for A/H1N1, A/H3N2 and B, respectively. High baseline SP rates, most probably reflecting frequent preimmunizations, explain partly the high postvaccination SP rates. SR rate was independently and inversely associated with baseline SP rate. Mycophenolate mofetil (MMF) usage was associated with a 2.6-5-fold lower SR. Nonetheless, these patients showed good postvaccination SP rates. A booster dose did not enhance SP or SR rates. Influenza vaccination neither affected allograft function nor caused rejection episodes. In conclusion, influenza vaccination is efficacious and safe in renal transplantation.

Infective endocarditis.

The diagnosis of infective endocarditis remains difficult. The complication rate is very high. Serious complications may occur and the overall mortality is still 20-25%. The sooner the treatment is started, the better the final result. Antibiotic therapy is essential but cardiac surgery is frequently necessary. Early surgery improves outcome. A multidisciplinary approach by internal medicine, cardiology and cardiac surgery facilitates the efficiency of diagnosis and treatment.

Fungemia at a tertiary care hospital: incidence, therapy, and distribution and antifungal susceptibility of causative species.

The aim of this study was to review fungal bloodstream infections at a large tertiary care hospital to evaluate the incidence of fungemia and the distribution of causative species during the period 2001-2005. Another aim was to assess the extent of antifungal resistance. A review of all episodes of fungemia at the University Hospitals of Leuven (Belgium) was conducted between January 2001 and December 2005. For the first yeast isolate collected from each non-mould fungemic episode during a 1-year period (June 2004-June 2005), susceptibility to seven antifungal agents was determined using Sensititre YeastOne plates (Trek Diagnostic Systems, East Grinstead, UK), and the antifungal therapy was reviewed. The annual incidence of fungemia ranged between 1.30 and 1.68 episodes per 10,000 patient-days (on a total of 2,680,932 patient-days), with a decreasing trend observed over the 5-year study period. The most common species were Candida albicans (59%), Candida glabrata (22%), Candida parapsilosis (10%), and Candida tropicalis (4%). Overall, fluconazole resistance was rare (1.6%) and was detected only in C. glabrata and C. krusei. Voriconazole and caspofungin inhibited 100% of the isolates at a concentration of