A set of two "two-tier" (thermotroph-psychrotroph) single quadrant plates (QPs) was dev... more A set of two "two-tier" (thermotroph-psychrotroph) single quadrant plates (QPs) was developed previously to allow convenient enumeration of numbers of colony-forming units of most pertinent pathogenic bacteria or marker bacteria in foods. These include Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, thermotrophic and psychrotrophic Enterobacteriaceae, Clostridium spp., and Enterococcus spp. As the QPs had given excellent results in monitoring samples of marketed food products potentially involved in food-transmitted illnesses, the approach was tested for practicability under military deployment and other constraints. Three approaches were envisaged: (i) validating lapse-free adherence to meticulously codified good military catering practices; (ii) acceptance/rejection testing of locally procured foods or meals; and (iii) employing rapid culture in support of evidence obtained by microscopy in attempts to identify foods involved in infectious or toxic diseas...
Nederlands tijdschrift voor geneeskunde, Jan 8, 2005
In the period July-September 2003, a multi-resistant Escherichia coli strain caused an outbreak o... more In the period July-September 2003, a multi-resistant Escherichia coli strain caused an outbreak on a surgical ward in the Deventer Hospital, the Netherlands. This strain produced a beta-lactamase with an extended spectrum, making it resistant to third generation cephalosporins. Furthermore, the strain was resistant to trimethoprim-sulphamethoxazole (co-trimoxazole), gentamicin and quinolones, so that only treatment with carbapenems was possible. 8 patients were colonised. Genotyping of the strains by means of amplified fragment length polymorphism indicated the spread of a single strain. A multidisciplinary crisis team coordinated the infection control measures and the communication to involved persons and the press. Control measures consisted of contact isolation of colonised patients and extra attention to hand hygiene. After this proved to be ineffective, all patients on the ward were screened and the ward was closed for several days. The outbreak was stopped by strict cohorting ...
Varicella-zoster virus (VZV) can cause severe disease in premature neonates. The fetus receives p... more Varicella-zoster virus (VZV) can cause severe disease in premature neonates. The fetus receives protective maternal VZV-immunoglobulin G (IgG) mainly in the third trimester of pregnancy. Therefore, premature neonates are considered at risk for VZV infection. Administration of varicella-zoster immunoglobulin (VZIG) within 96 hours after exposure effectively prevents severe illness in susceptible patients. The objectives of this study were to define the major determinants of the neonatal VZV-IgG titer and to determine the half-life of transplacentally acquired VZV-IgG. Guidelines provided by the Centers for Disease Control and Prevention for the use of VZIG in (premature) neonates were evaluated. VZV-IgG titers were measured in sera of 221 neonates and 43 mothers using a quantitative enzyme-linked immunosorbent assay. In 27 neonates, VZV-IgG titers were followed for up to 14 weeks. In a linear regression model, the maternal antibody titer was the major determinant of the neonatal tite...
Nederlands tijdschrift voor geneeskunde, Jan 31, 2001
From December 1999 to March 2000 a nosocomial outbreak of multiresistant Enterobacter cloacae occ... more From December 1999 to March 2000 a nosocomial outbreak of multiresistant Enterobacter cloacae occurred in the neonatal intensive care unit (NICU) at the VU Medical Center, Amsterdam, the Netherlands. Twenty-six patients were infected or colonized with this strain resistant to third generation cephalosporins and with decreased sensitivity for aminoglycosides. Three neonates experienced sepsis with E. cloacae with serious clinical symptoms and two of them died. Comparison of the Enterobacter isolates by amplified-fragment length polymorphism indicated that this outbreak was caused by the spread of a single strain. Infection control precautions were initiated in order to stop further spread; barrier precautions, enforcement of hand disinfection and cohorting of colonized patients. A multidisciplinary crisis team coordinated these infection control precautions and informed all persons involved. Analysis of antibiotic usage in 1999 showed an increase in the use of third generation cephal...
In 1998, an outbreak of systemic infections caused by Bacillus cereus occurred in the Neonatal In... more In 1998, an outbreak of systemic infections caused by Bacillus cereus occurred in the Neonatal Intensive Care Unit of the University Hospital Vrije Universiteit, Amsterdam, The Netherlands. Three neonates developed sepsis with positive blood cultures. One neonate died, and the other two neonates recovered. An environmental survey, a prospective surveillance study of neonates, and a case control study were performed, in combination with molecular typing, in order to identify potential sources and transmission routes of infection. Genotypic fingerprinting by amplified-fragment length polymorphism (AFLP) showed that the three infections were caused by a single clonal type of B. cereus. The same strain was found in trachea aspirate specimens of 35 other neonates. The case control study showed mechanical ventilation with a Sensormedics ventilation machine to be a risk factor for colonization and/or infection (odds ratio, 9.8; 95% confidence interval, 1.1 to 88.2). Prospective surveillanc...
Summary  T1 and T2 weighted mr images of the brain are very suitable to demonstrate the integrity... more Summary  T1 and T2 weighted mr images of the brain are very suitable to demonstrate the integrity of the infant's brain. Diffusion weighted mri is a new promising technique which is sensitive to conditions with restricted water diffusion, e.g. cytotoxic edema in infection and ischaemia. The value of this new mri technique will be discussed in relation to two patients with
Between December 2010 and April 2012, intensive care unit (ICU) patients in our hospital were inf... more Between December 2010 and April 2012, intensive care unit (ICU) patients in our hospital were infrequently colonized with extended-spectrum β-lactamase-positive bacteria (ESBLs). We hypothesized that these ESBLs originated from patients' room sinks, and this was prospectively investigated by weekly culturing of patients and sinks during a 20-week period. ESBLs were isolated from all 13 sinks. Four patients became colonized with ESBLs that were genetically identical to ESBLs that had previously been isolated from the sink. One of these patients died of pneumonia caused by the ESBL. Transmission from sinks to patients was stopped by integrating self-disinfecting siphons to all sinks on the ICU.
Treatment of choice for rectal carcinoma is short-term preoperative radiotherapy (5 x 5 Gy) follo... more Treatment of choice for rectal carcinoma is short-term preoperative radiotherapy (5 x 5 Gy) followed by a total mesorectal excision (TME) of the rectum. This treatment has led to a reduction in local recurrence 2 years after surgery from 8.2 to 2.4%. Side effects of this treatment seem to be marginal and of no consequence. After introduction of short-term preoperative radiotherapy we noticed a rise in the postoperative presacral abscess formation which is difficult to treat and results in readmissions and prolonged hospital stay. Research was needed to investigate whether short-term preoperative radiotherapy can be held accountable for the presumed rise in presacral abscess formation in the treatment of rectal carcinoma. A retrospective study was performed over the period January 2000-October 2004. Two groups were formed. Group 1 existed of 30 patients who underwent a TME of the rectum without short-term preoperative radiotherapy. Group two existed of 35 patients who underwent a TME of the rectum with short-term preoperative radiotherapy. Statistical analysis showed a significant increase in presacral abscess formation (13 vs. 40%) after introduction of short-term preoperative radiotherapy. Radiotherapy proved to be an important risk factor. Reduction in incidence of local recurrence was not evident. We found a significant increase in presacral abscess formation strongly suggestive due to the introduction of short-term preoperative radiotherapy in the treatment of rectal carcinoma. We noticed no reduction in incidence of local recurrence. We advocate that additional research is needed in order to formulate extra patient selection criteria for the use of preoperative radiotherapy in the treatment of rectal cancer.
A set of two "two-tier" (thermotroph-psychrotroph) single quadrant plates (QPs) was dev... more A set of two "two-tier" (thermotroph-psychrotroph) single quadrant plates (QPs) was developed previously to allow convenient enumeration of numbers of colony-forming units of most pertinent pathogenic bacteria or marker bacteria in foods. These include Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, thermotrophic and psychrotrophic Enterobacteriaceae, Clostridium spp., and Enterococcus spp. As the QPs had given excellent results in monitoring samples of marketed food products potentially involved in food-transmitted illnesses, the approach was tested for practicability under military deployment and other constraints. Three approaches were envisaged: (i) validating lapse-free adherence to meticulously codified good military catering practices; (ii) acceptance/rejection testing of locally procured foods or meals; and (iii) employing rapid culture in support of evidence obtained by microscopy in attempts to identify foods involved in infectious or toxic diseas...
Nederlands tijdschrift voor geneeskunde, Jan 8, 2005
In the period July-September 2003, a multi-resistant Escherichia coli strain caused an outbreak o... more In the period July-September 2003, a multi-resistant Escherichia coli strain caused an outbreak on a surgical ward in the Deventer Hospital, the Netherlands. This strain produced a beta-lactamase with an extended spectrum, making it resistant to third generation cephalosporins. Furthermore, the strain was resistant to trimethoprim-sulphamethoxazole (co-trimoxazole), gentamicin and quinolones, so that only treatment with carbapenems was possible. 8 patients were colonised. Genotyping of the strains by means of amplified fragment length polymorphism indicated the spread of a single strain. A multidisciplinary crisis team coordinated the infection control measures and the communication to involved persons and the press. Control measures consisted of contact isolation of colonised patients and extra attention to hand hygiene. After this proved to be ineffective, all patients on the ward were screened and the ward was closed for several days. The outbreak was stopped by strict cohorting ...
Varicella-zoster virus (VZV) can cause severe disease in premature neonates. The fetus receives p... more Varicella-zoster virus (VZV) can cause severe disease in premature neonates. The fetus receives protective maternal VZV-immunoglobulin G (IgG) mainly in the third trimester of pregnancy. Therefore, premature neonates are considered at risk for VZV infection. Administration of varicella-zoster immunoglobulin (VZIG) within 96 hours after exposure effectively prevents severe illness in susceptible patients. The objectives of this study were to define the major determinants of the neonatal VZV-IgG titer and to determine the half-life of transplacentally acquired VZV-IgG. Guidelines provided by the Centers for Disease Control and Prevention for the use of VZIG in (premature) neonates were evaluated. VZV-IgG titers were measured in sera of 221 neonates and 43 mothers using a quantitative enzyme-linked immunosorbent assay. In 27 neonates, VZV-IgG titers were followed for up to 14 weeks. In a linear regression model, the maternal antibody titer was the major determinant of the neonatal tite...
Nederlands tijdschrift voor geneeskunde, Jan 31, 2001
From December 1999 to March 2000 a nosocomial outbreak of multiresistant Enterobacter cloacae occ... more From December 1999 to March 2000 a nosocomial outbreak of multiresistant Enterobacter cloacae occurred in the neonatal intensive care unit (NICU) at the VU Medical Center, Amsterdam, the Netherlands. Twenty-six patients were infected or colonized with this strain resistant to third generation cephalosporins and with decreased sensitivity for aminoglycosides. Three neonates experienced sepsis with E. cloacae with serious clinical symptoms and two of them died. Comparison of the Enterobacter isolates by amplified-fragment length polymorphism indicated that this outbreak was caused by the spread of a single strain. Infection control precautions were initiated in order to stop further spread; barrier precautions, enforcement of hand disinfection and cohorting of colonized patients. A multidisciplinary crisis team coordinated these infection control precautions and informed all persons involved. Analysis of antibiotic usage in 1999 showed an increase in the use of third generation cephal...
In 1998, an outbreak of systemic infections caused by Bacillus cereus occurred in the Neonatal In... more In 1998, an outbreak of systemic infections caused by Bacillus cereus occurred in the Neonatal Intensive Care Unit of the University Hospital Vrije Universiteit, Amsterdam, The Netherlands. Three neonates developed sepsis with positive blood cultures. One neonate died, and the other two neonates recovered. An environmental survey, a prospective surveillance study of neonates, and a case control study were performed, in combination with molecular typing, in order to identify potential sources and transmission routes of infection. Genotypic fingerprinting by amplified-fragment length polymorphism (AFLP) showed that the three infections were caused by a single clonal type of B. cereus. The same strain was found in trachea aspirate specimens of 35 other neonates. The case control study showed mechanical ventilation with a Sensormedics ventilation machine to be a risk factor for colonization and/or infection (odds ratio, 9.8; 95% confidence interval, 1.1 to 88.2). Prospective surveillanc...
Summary  T1 and T2 weighted mr images of the brain are very suitable to demonstrate the integrity... more Summary  T1 and T2 weighted mr images of the brain are very suitable to demonstrate the integrity of the infant's brain. Diffusion weighted mri is a new promising technique which is sensitive to conditions with restricted water diffusion, e.g. cytotoxic edema in infection and ischaemia. The value of this new mri technique will be discussed in relation to two patients with
Between December 2010 and April 2012, intensive care unit (ICU) patients in our hospital were inf... more Between December 2010 and April 2012, intensive care unit (ICU) patients in our hospital were infrequently colonized with extended-spectrum β-lactamase-positive bacteria (ESBLs). We hypothesized that these ESBLs originated from patients' room sinks, and this was prospectively investigated by weekly culturing of patients and sinks during a 20-week period. ESBLs were isolated from all 13 sinks. Four patients became colonized with ESBLs that were genetically identical to ESBLs that had previously been isolated from the sink. One of these patients died of pneumonia caused by the ESBL. Transmission from sinks to patients was stopped by integrating self-disinfecting siphons to all sinks on the ICU.
Treatment of choice for rectal carcinoma is short-term preoperative radiotherapy (5 x 5 Gy) follo... more Treatment of choice for rectal carcinoma is short-term preoperative radiotherapy (5 x 5 Gy) followed by a total mesorectal excision (TME) of the rectum. This treatment has led to a reduction in local recurrence 2 years after surgery from 8.2 to 2.4%. Side effects of this treatment seem to be marginal and of no consequence. After introduction of short-term preoperative radiotherapy we noticed a rise in the postoperative presacral abscess formation which is difficult to treat and results in readmissions and prolonged hospital stay. Research was needed to investigate whether short-term preoperative radiotherapy can be held accountable for the presumed rise in presacral abscess formation in the treatment of rectal carcinoma. A retrospective study was performed over the period January 2000-October 2004. Two groups were formed. Group 1 existed of 30 patients who underwent a TME of the rectum without short-term preoperative radiotherapy. Group two existed of 35 patients who underwent a TME of the rectum with short-term preoperative radiotherapy. Statistical analysis showed a significant increase in presacral abscess formation (13 vs. 40%) after introduction of short-term preoperative radiotherapy. Radiotherapy proved to be an important risk factor. Reduction in incidence of local recurrence was not evident. We found a significant increase in presacral abscess formation strongly suggestive due to the introduction of short-term preoperative radiotherapy in the treatment of rectal carcinoma. We noticed no reduction in incidence of local recurrence. We advocate that additional research is needed in order to formulate extra patient selection criteria for the use of preoperative radiotherapy in the treatment of rectal cancer.
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