Added diagnostic value of broad-range 16S PCR on periprosthetic tissue and clinical specimens from other normally sterile body sites.

AIMS: Evaluation of 16S PCR in addition to the standard culture to improve the pathogen detection rate in clinical specimens. METHODS AND RESULTS: Microbiological culture and direct 16S PCR was performed on specimens from suspected prosthetic joint infection patients (cohort-1) and on tissues and fluids from other normally sterile body sites (cohort-2). Based on clinical and microbiological data, the detection rate for both methods was assessed, assuming no superiority of either 16S PCR or culture. In cohort-1, 469 specimens were obtained. Culture was positive in 170 (36·2%) specimens, 16S PCR detected 70 (41·2%) of those pathogens. Additionally, 16S PCR detected pathogens in 13 of 299 (4·3%) culture-negative specimens. In cohort-2, pathogens were cultured in 52 of 430 (12·1%) specimens and 16S PCR revealed those pathogens in 32 (61·5%) specimens. 16S PCR detected pathogens in 31 of 378 (8·2%) culture-negative specimens. CONCLUSIONS: Overall, the yield with 16S PCR was low. For cohort-1 16S PCR detected pathogens in 4·3% of culture-negative specimens, where this was 8·2% for cohort-2. SIGNIFICANCE AND IMPACT OF THE STUDY: Although direct 16S PCR cannot replace culture, it may offer a valuable additional diagnostic option for detection of difficult to culture micro-organisms in culture-negative clinical specimens.

Secular trends in nosocomial bloodstream infections: antibiotic-resistant bacteria increase the total burden of infection.

BACKGROUND: It is unknown whether rising incidence rates of nosocomial bloodstream infections (BSIs) caused by antibiotic-resistant bacteria (ARB) replace antibiotic-susceptible bacteria (ASB), leaving the total BSI rate unaffected. METHODS: We investigated temporal trends in annual incidence densities (events per 100 000 patient-days) of nosocomial BSIs caused by methicillin-resistant Staphylococcus aureus (MRSA), ARB other than MRSA, and ASB in 7 ARB-endemic and 7 ARB-nonendemic hospitals between 1998 and 2007. RESULTS: 33 130 nosocomial BSIs (14% caused by ARB) yielded 36 679 microorganisms. From 1998 to 2007, the MRSA incidence density increased from 0.2 to 0.7 (annual increase, 22%) in ARB-nonendemic hospitals, and from 3.1 to 11.7 (annual increase, 10%) in ARB-endemic hospitals (P = .2), increasing the incidence density difference between ARB-endemic and ARB-nonendemic hospitals from 2.9 to 11.0. The non-MRSA ARB incidence density increased from 2.8 to 4.1 (annual increase, 5%) in ARB-nonendemic hospitals, and from 1.5 to 17.4 (annual increase, 22%) in ARB-endemic hospitals (P < .001), changing the incidence density difference from -1.3 to 13.3. Trends in ASB incidence densities were similar in both groups (P = .7). With annual increases of 3.8% and 5.4% of all nosocomial BSIs in ARB-nonendemic and ARB-endemic hospitals, respectively (P < .001), the overall incidence density difference of 3.8 increased to 24.4. CONCLUSIONS: Increased nosocomial BSI rates due to ARB occur in addition to infections caused by ASB, increasing the total burden of disease. Hospitals with high ARB infection rates in 2005 had an excess burden of BSI of 20.6 per 100 000 patient-days in a 10-year period, mainly caused by infections with ARB.

Successful containment of two vancomycin-resistant Enterococcus faecium (VRE) outbreaks in a Dutch teaching hospital using environmental sampling and whole-genome sequencing.

BACKGROUND: Vancomycin-resistant enterococci (VRE) may cause nosocomial outbreaks. This article describes all VRE carriers that were identified in 2018 at Elisabeth-Tweesteden Hospital, Tilburg, The Netherlands. AIM: To investigate the genetic relatedness of VRE isolates and the possibility of a common environmental reservoir using environmental sampling and whole-genome sequencing (WGS). METHODS: Infection control measures consisted of contact isolation, contact surveys, point prevalence screening, environmental sampling, cleaning and disinfection. VRE isolates were sequenced using a MiSeq sequencer (Illumina, San Diego, CA, USA), and assembled using SPAdes v.3.10.1. A minimal spanning tree and a neighbour joining tree based on allelic diversity of core-genome multi-locus sequence typing and accessory genes were created using Ridom SeqSphere+ software (Ridom GmbH, Münster, Germany). FINDINGS: Over a 1-year period, 19 VRE carriers were identified; of these, 17 were part of two outbreaks. Before environmental cleaning and disinfection, 55 (14%) environmental samples were VRE-positive. Fifty-one isolates (23 patient samples and 28 environmental samples) were available for WGS analysis. Forty-four isolates were assigned to ST117-vanB, five were assigned to ST17-vanB, and two were assigned to ST80-vanB. Isolates from Outbreak 1 (N=22) and Outbreak 2 (N=22) belonged to ST117-vanB; however, WGS showed a different cluster type with 257 allelic differences. CONCLUSION: WGS of two outbreak strains provided discriminatory information regarding genetic relatedness, and rejected the hypothesis of a common environmental reservoir. A high degree of environmental contamination was associated with higher VRE transmission. Quantification of environmental contamination may reflect the potential for VRE transmission and could therefore support the infection control measures.

Short-course aminoglycosides as adjunctive empirical therapy in patients with Gram-negative bloodstream infection, a cohort study.

OBJECTIVE: Short-course aminoglycosides as adjunctive empirical therapy to ß-lactams in patients with a clinical suspicion of sepsis are used to broaden antibiotic susceptibility coverage and to enhance bacterial killing. We quantified the impact of this approach on 30-day mortality in a subset of sepsis patients with a Gram-negative bloodstream infection. METHODS: From a prospective cohort study conducted in seven hospitals in the Netherlands between June 2013 and November 2015, we selected all patients with Gram-negative bloodstream infection (GN-BSI). Short-course aminoglycoside therapy was defined as tobramycin, gentamicin or amikacin initiated within a 48-hour time window around blood-culture obtainment, and prescribed for a maximum of 2 days. The outcome of interest was 30-day all-cause mortality. Confounders were selected a priori for adjustment using a propensity score analysis with inverse probability weighting. RESULTS: A total of 626 individuals with GN-BSI who received ß-lactams were included; 156 (24.9%) also received aminoglycosides for a median of 1 day. Patients receiving aminoglycosides more often had septic shock (31/156, 19.9% versus 34/470, 7.2%) and had an eight-fold lower risk of inappropriate treatment (3/156, 1.9% versus 69/470, 14.7%). Thirty-day mortality was 17.3% (27/156) and 13.6% (64/470) for patients receiving and not receiving aminoglycosides, respectively; yielding crude and adjusted odds ratios for 30-day mortality for patients treated with aminoglycosides of 1.33 (95% CI 0.80-2.15) and 1.57 (0.84-2.93), respectively. CONCLUSIONS: Short-course adjunctive aminoglycoside treatment as part of empirical therapy with ß-lactam antibiotics in patients with GN-BSI did not result in improved outcomes, despite better antibiotic coverage of pathogens.

Extended-spectrum ß-lactamase (ESBL) polymerase chain reaction assay on rectal swabs and enrichment broth for detection of ESBL carriage.

BACKGROUND: Extended-spectrum ß-lactamase (ESBL) screening and contact precautions on patients at high risk for ESBL carriage are considered important infection control measures. Since contact precautions are costly and may negatively impact patient care, rapid exclusion of ESBL carriage and therefore earlier discontinuation of contact precautions are desired. AIM: In the present study, the performance of an ESBL polymerase chain reaction (PCR) targeting blaCTX-M genes was evaluated as a screening assay for ESBL carriage. METHODS: Two methods were assessed: PCR performed directly on rectal swabs and PCR on enrichment broth after incubation overnight. The reference standard was culture of ESBL-producing Enterobacteriaceae on selective agar after overnight enrichment and confirmation by the combination disc diffusion method. Microarray was used for discrepancy analysis. A secondary analysis was performed to evaluate the added value of including a blaSHV target in the PCR. FINDINGS: A total of 551 rectal swabs from 385 patients were included, of which 28 (5%) were ESBL positive in culture. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 86%, 98%, 67%, and 99%, respectively, for PCR directly on swabs, and 96%, 98%, 75%, and 100%, respectively, for PCR on enrichment broth. Adding a blaSHV target to the assay resulted in a lower PPV without increasing the sensitivity and NPV. CONCLUSION: Screening for ESBL by PCR directly on rectal swabs has a high negative predictive value, is up to 48h faster than traditional culture and therefore facilitates earlier discontinuation of contact precautions, thereby improving patient care and saving valuable resources in the hospital.

Evaluation of a chromogenic agar (MRSASelect) for the detection of meticillin-resistant Staphylococcus aureus with clinical samples in The Netherlands.

A novel chromogenic medium for the detection of meticillin-resistant Staphylococcus aureus (MRSA), MRSASelect (Bio-Rad), was evaluated with clinical samples in a public health laboratory in The Netherlands. In total, 3000 samples were tested in the period January to March 2005, including 972 nose, 972 throat, 968 perineum, and 88 wound or urine samples. Presumptive MRSA colonies appeared pink/mauve on the MRSASelect medium. The performance of MRSASelect medium was compared with the routine screening method. Evaluation of the colony morphology showed that all confirmed MRSA isolates grew as pink/mauve colonies. None of the white colonies were MRSA strains. The number of false-positive pink/mauve colonies increased after prolonged incubation from 20 to 48 h. The specificity decreased from 92 % after 20 h incubation to 89 % after 48 h incubation. In total 70 MRSA strains were isolated, 55 of which were detected by the MRSASelect medium and 55 were detected by the routine screening method. Sensitivity was 78.6 % for both test procedures, and specificities were 99.5 and 100 %, respectively for the MRSASelect medium and the routine screening method. The addition of an enrichment broth to the MRSASelect medium increased the number of MRSA strains detected by 12 %. In total, 18 patients were MRSA positive, 4 of these were detected by the MRSASelect medium only and 1 was detected by the routine screening method only. Sensitivity on patient level was 94.4 and 77.8 % for the MRSASelect medium and the routine screening method, respectively, while specificities were 99.7 and 99.0 %.

Identification and susceptibility testing of Staphylococcus aureus by direct inoculation from positive BACTEC blood culture bottles.

This study explored the possibility of combining direct inoculation of tube coagulase and DNase tests, and the VITEK2 system, from BACTEC blood culture bottles in order to achieve rapid identification and susceptibility testing of Staphylococcus aureus. All isolates were identified correctly as S. aureus or coagulase-negative staphylococci (CNS). Antimicrobial susceptibility testing with the VITEK2 system gave 99.6% correct category agreement, with 0.1% very major errors and 0.3% minor errors among S. aureus isolates, and 97.4% correct category agreement, with 0.9% very major errors and 1.7% minor errors among CNS isolates. The results suggested that direct identification and susceptibility testing is sufficiently accurate for immediate reporting.

Procoagulant activity of endocardial vegetations and blood monocytes in rabbits with Streptococcus sanguis endocarditis.

To investigate activation of the coagulation system in bacterial endocarditis, we determined the procoagulant activity of blood monocytes isolated from rabbits with Streptococcus sanguis-infected or sterile catheter-induced endocardial vegetations. This activity was determined directly after isolation from the peripheral blood and after stimulation in vitro by either endotoxin or by phagocytosis of S. sanguis. The procoagulant activity of the vegetations of these rabbits was also determined. The procoagulant activity of blood monocytes of rabbits with S. sanguis endocarditis was found to be similar to the activity of monocytes of rabbits with sterile vegetations, both at the time of isolation and after stimulation in vitro by exposure to endotoxin or phagocytosis of bacteria. The procoagulant activity of infected vegetations was significantly higher than that of sterile vegetations. We conclude that in bacterial endocarditis the coagulation system is activated locally at the site of the vegetation. Triggering probably occurs by thromboplastin generated by monocytes activated by phagocytosis of bacteria on the vegetational surface.

Prevalence and determinants of fecal colonization with vancomycin-resistant Enterococcus in hospitalized patients in The Netherlands.

OBJECTIVE: To determine the prevalence and determinants of fecal carriage of vancomycin-resistant enterococci (VRE) in intensive care unit (ICU), hematology-oncology, and hemodialysis patients in The Netherlands. DESIGN: Descriptive, multicenter study, with yearly 1-week point-prevalence assessments between 1995 and 1998. POPULATION: All patients hospitalized on the testing days in ICUs and hematology-oncology wards in nine hospitals in The Netherlands were included. METHODS: Rectal swabs obtained from 1,112 patients were screened for enterococci in a selective broth and subcultured on selective media with and without 6 mg/L vancomycin. Resistance genotypes were determined by polymerase chain reaction. Further characterization of VRE strains was done by pulsed-field gel electrophoresis (PFGE). We studied possible determinants of VRE colonization with a logistic regression analysis model. Determinants analyzed included gender, age, and log-transformed length of prior hospital stay. RESULTS: The results showed that 614 (55%) of 1,112 patients were colonized with vancomycin-sensitive enterococci, and 15 (1.4%) of 1,112 carried VRE. No increase in VRE colonization was observed from 1995 to 1998. Eleven strains were identified as Enterococcus faecium and four as Enterococcus faecalis. All E faecium and one E faecalis carried the vanA gene; the other E faecalis strains harbored the vanB gene. PFGE revealed that three vanB VRE isolated from patients hospitalized in one single ICU were related, suggesting nosocomial transmission. Though higher age seemed associated with VRE colonization, exclusion of patients with the nosocomial strain from the regression analysis decreased this relation to nonsignificant. Duration of hospital stay was not associated with VRE colonization. CONCLUSION: VRE colonization in Dutch hospitals is an infrequent phenomenon. Although nosocomial spread occurs, most observed cases were unrelated, which suggests the possibility of VRE acquisition from outside the hospital. Prolonged hospital stay, age, and gender proved unrelated to VRE colonization.

Decolonization of methicillin-resistant Staphylococcus aureus using oral vancomycin and topical mupirocin.

The objective of this study was to assess the efficacy and safety of a short course of oral vancomycin and intranasal mupirocin ointment in the eradication of methicillin-resistant Staphylococcus aureus (MRSA) colonization. During an outbreak of MRSA, the colonized subjects received oral vancomycin and topical mupirocin. They were screened for MRSA 1, 3, 6 and 12 months after decolonization. A questionnaire was developed to evaluate the side-effects of oral vancomycin. Thirty-five subjects were treated. Clearance was achieved in all cases, in 24 (69%) subjects after one course of therapy. Twenty-eight (80%) subjects experienced some side-effects, including six (17%) who did not tolerate oral vancomycin. Although oral vancomycin, in combination with topical mupirocin, is effective in the elimination of MRSA colonization, there is a need for further studies to confirm our results and to evaluate the safety of oral vancomycin.

Infectious complications and antibiotic use in renal transplant recipients during a 1-year follow-up.

OBJECTIVE: To evaluate infectious complications and antibiotic use in 192 renal transplant recipients. METHODS: Infectious complications and antibiotic use were monitored in all patients receiving renal transplantation at our center from 1992 to 1997. Risk factors for infectious complications were evaluated. Transplants and patient survival were monitored. The follow-up period was 1 year. RESULTS: One-hundred and ninety-two patients received renal transplants during the study period. The mean duration of urethral catheterisation after transplantation was 10.5 days (SD = 5). Seventy-one per cent (n = 137) of patients had at least one infectious episode. In all, 284 infectious episodes were monitored. The most frequent infections were: urinary tract infections 61%, respiratory tract infections 8%, intra-abdominal infections 7%, and cytomegalovirus infection 8%. Escherichia coli and Enterococcus faecalis were the most frequently isolated microorganisms. Seventy-four per cent (n = 142) of patients received 314 antimicrobial courses (284 for therapy, and 30 for prophylaxis). Female gender and duration of urethral catheterisation were risk factors for urinary tract infection. Cytomegalovirus reactivation was associated with acute graft rejection and additional immunosuppressive therapy. Overall mortality was 4%. Infection-related mortality was 2.6%. Mortality was associated with Enterobacteriaceae in three patients, with Pseudomonas aeroginosa in one patient and with Enterococcus faecalis in one patient. CONCLUSIONS: The incidence of infectious complications remains high in renal transplant recipients. Most cases of mortality were associated with infections. Early removal of the urethral catheter to reduce the risk of urinary tract infections is recommended.

The risk of Strongyloides stercoralis transmission from patients with disseminated strongyloidiasis to the medical staff.

To assess the risk of Strongyloides stercoralis transmission from two patients with disseminated strongyloidiasis to medical staff who had been in close contact with the patients, blood and stool specimens were obtained from medical staff two to three months after close contact with the patients. Antibodies to S. stercoralis were determined in blood. Stool specimens were tested for parasites with three different procedures.Forty-one medical staff were included. Culture and stool examination were negative in all subjects. Serology was negative in all subjects but one who had a borderline titer without signs or symptoms of strongyloidiasis. No evidence of transmission of S. stercoralis from patients with disseminated strongyloidiasis to medical staff was found.

Chronic meningococcaemia: a case report.

Chronic meningococcaemia (CM), caused by the bacterium Neisseria meningitidis is reported in a 27-year-old Indonesian man. The main symptoms were intermittent fever, skin rash and arthralgia. The pathogenesis, symptoms, differential diagnoses and treatment of CM are discussed.

Aortic graft infection by Lactobacillus casei: a case report.

A 65-year-old man with an abdominal aortic endoprosthesis presented with fever without other symptoms. Investigations revealed Lactobacillus casei bacteraemia. The Lactobacillus graft infection was at first successfully treated by antibiotic therapy. However, during follow-up a relapse occurred, and after surgical replacement of the graft the patient was cured. At surgery an aortoenteric fistula was found as source of the infection.

BCG immunotherapy: be cautious of granulomas. Disseminated BCG infection and mycotic aneurysm as late complications of intravesical BCG instillations.

We describe a 65-year-old man with a granulomatous hepatitis and a progressive mycotic aneurysm of the abdominal aorta. One year before he received intravesical bacillus Calmette--Guérin (BCG) for carcinoma of the bladder without any complaints. Only post-mortem investigations could confirm that he suffered from a systemic BCG infection. Literature is reviewed for this rare complication.

Optimisation of the antibiotic guidelines in The Netherlands. VII. SWAB guidelines for antimicrobial therapy in adult patients with infectious endocarditis.

The Working Party on Antibiotic Policy (Dutch acronym is SWAB) is a Dutch organisation that develops guidelines for in-hospital antimicrobial therapy of bacterial infectious diseases. This present guideline describes the antimicrobial treatment for adult patients with infective endocarditis. The choice and duration of antimicrobial therapy is determined by the infecting micro-organism, sensitivity of this micro-organism for antimicrobial therapy, location of the endocarditis, left-sided or right-sided, and presence of intracardial prosthetic material. In this guideline, the empirical therapy for endocarditis is discussed as well as the therapy for the most frequent causative organisms: streptococci, enterococci, staphylococci and HACEK micro-organisms.

[Diagnostic image (157). A man with fever and a 'tache noire' after a holiday in South Africa. Rickettsiosis, probably African tick-bite fever]. / Diagnose in beeld (157). Een man met koorts en een 'tache noire' na een vakantie in Zuid-Afrika. Rickettsiose, waarschijnlijk Afrikaanse tekenkoorts.

A 54-year-old man presented with fever and an eschar, probably caused by African tick-bite fever, contracted during a holiday in South Africa. He recovered rapidly after treatment with doxycyclin.

[An unusual hospital infection: Aeromonas hydrophila infection due to the use of leeches]. / Een ongewone ziekenhuis-infectie: Aeromonas hydrophila-infectie bij gebruik van bloedzuigers.

A patient is described with an infection with Aeromonas hydrophila after the use of medical leeches to improve the circulation of a congested region of surgery. The use of medical leeches and the treatment of a leech-related infection are discussed.

[Mycetoma of the foot; a disease from the tropics]. / Mycetoom van de voet; een ziekte uit de tropen.

Two patients, a Surinamese man aged 50 and a Surinamese woman aged 56 exhibited a mycetoma of the foot, 30 and 28 years, respectively, after a local injury. Pathological examination revealed an aspecific chronic granulomatous inflammation. As causative agents a Fusarium species and a Cladosporium normodendrum, respectively, were cultured. The treatment consisted of curettage of fistulous ducts and administration of itraconazole.

[A patient with chronic mucormycosis]. / Een patiënt met chronische mucormycosis.

Rhinocerebral mucormycosis was diagnosed in a 75-year-old woman with a history of type II diabetes mellitus. This rare opportunistic infection is caused by fungi belonging to the order of Mucorales. The patient had a severe osteomyelitis of the base of the skull, resulting in complaints of headache and diplopia. She was treated with intravenous colloidal amphotericin B, surgical excision, and later with liposomal amphotericin B. She died of respiratory failure. Mucormycosis is usually a rapidly fulminant infection. This patient showed a remarkably chronic course.