From a case-control survey to a diagnostic viral gastroenteritis panel for testing of general practitioners' patients

OBJECTIVE

To evaluate the pathogenicity of a broad range of 11 possible gastroenteritis viruses, by means of statistical relationships with cases vs. controls, or Ct-values, in order to establish the most appropriate diagnostic panel for our general practitioner (GP) patients in the Netherlands (2010-2012).

METHODS

Archived stool samples from 1340 cases and 1100 controls were retested using internally controlled multiplex real-time PCRs for putative pathogenic gastroenteritis viruses: adenovirus, astrovirus, bocavirus, enterovirus, norovirus GI and GII, human parechovirus, rotavirus, salivirus, sapovirus, and torovirus.

RESULTS

The prevalence of any virus in symptomatic cases and asymptomatic controls was 16.6% (223/1340) and 10.2% (112/1100), respectively. Prevalence of astrovirus (adjusted odds ratio (aOR) 10.37; 95% confidence interval (CI) 1.34-80.06) and norovirus GII (aOR 3.10; CI 1.62-5.92) was significantly higher in cases versus controls. Rotavirus was encountered only in cases. We did not find torovirus and there was no statistically significant relationship with cases for salivirus (aOR 1,67; (CI) 0.43-6.54)), adenovirus non-group F (aOR 1.20; CI 0.75-1.91), bocavirus (aOR 0.85; CI 0.05-13.64), enterovirus (aOR 0.83; CI 0.50-1.37), human parechovirus (aOR 1.61; CI 0.54-4.77) and sapovirus (aOR 1.15; CI 0.67-1.98). Though adenovirus group F (aOR 6.37; CI 0.80-50.92) and norovirus GI (aOR 2.22, CI: 0.79-6.23) are known enteropathogenic viruses and were more prevalent in cases than in controls, this did not reach significance in this study. The Ct value did not discriminate between carriage and disease in PCR-positive subjects.

CONCLUSIONS

In our population, diagnostic gastroenteritis tests should screen for adenovirus group F, astrovirus, noroviruses GI and GII, and rotavirus. Case-control studies as ours are lacking and should also be carried out in populations from other epidemiological backgrounds.

Bacterial agents in vulvovaginitis and vaginal discharge: a 10-year retrospective study in the Netherlands

Vulvovaginitis is a common problem in the GP's practice. Causes are bacterial vaginosis (BV), Candida infection and sexually transmitted infections (STIs). Only if empirical treatment fails, a vaginal swab is sent in for culture and BV detection. However, without culture essential, bacterial pathogens may escape diagnosis. Many molecular BV assays have recently appeared on the marketplace, all quite differing in price and targets. However, for years, the Nugent score has been the gold standard for BV detection. We analysed retrospectively 10 years of microbiology results of vulvovaginal swabs, focusing on less frequently reported bacterial pathogens, and assessed the characteristics of BV diagnostics. Vulvovaginal swabs sent in between 2010 and 2020 from > 11,000 GP patients with vulvovaginitis associated symptoms, but negative STI tests, were analysed. First cultures and repeat cultures after at least 6 months were included in four age groups: < 12, 12-17, 18-51 and > 51 years. Candida species and BV were most frequently found, with the highest prevalence in premenopausal women. Haemophilus influenzae, beta-haemolytic streptococci, Streptococcus pneumoniae and Staphylococcus aureus were isolated in 5.6% of all cultures, with the highest percentages in children and postmenopausal women. If empirical treatment of vulvovaginitis fails, bacterial culture should be performed to detect all potentially pathogenic microorganisms to obtain a higher rate of successful diagnosis and treatment, avoiding unnecessary antimicrobial use and costs. For BV detection, molecular testing may seem attractive, but Nugent scoring still remains the low-cost gold standard. We recommend incorporating the above in the appropriate guidelines.

Room Sharing in Hospitalized Children With Bronchiolitis and the Occurrence of Hospital-Acquired Infections: A Prospective Cohort Study

OBJECTIVES

To determine the prevalence and severity of hospital-acquired infections (HAIs) in children hospitalized for bronchiolitis when patients share a room, irrespective of the causative virus.

METHODS

A prospective cohort study during 4 winter seasons (2012-2016) was conducted in a Dutch general pediatric ward including otherwise healthy children <2 years of age hospitalized for bronchiolitis. Patients shared a 1-to-4-bed hospital room irrespective of virological diagnosis. The main outcome measures were HAIs assessed through multiplex polymerase chain reaction and disease severity.

RESULTS

HAIs occurred in 28 of 218 included patients (12.8%), most frequently with rhinovirus (17 of 28; 60.7%). In 3 (10.7%) of 28 HAIs, the same virus was identified in roommates. Only 1 patient became cross-infected with respiratory syncytial virus, although this patient never shared a room with a patient infected with respiratory syncytial virus. HAI was not associated with more severe disease. The median length of hospitalization was 3.5 days (interquartile range [IQR] 1-6) compared with 3 days (IQR 2-6; P = .86); the number of PICU admissions was 0% versus 5.3% (P = .21); the median days of oxygen supplementation was 2.5 (IQR 1-4) versus 2 (IQR 1-4; P = .58); the median days of tube feeding was 2 (IQR 0-5) versus 2 (interquartile range: 0-5; P = .77); and the readmission rate was 0% versus 5.8% (P = .19) in patients with and without HAI, respectively.

CONCLUSIONS

HAIs among patients with bronchiolitis are common but not associated with more severe disease. Room sharing with appropriate hygiene does not play a relevant role in the transmission of viruses between patients with bronchiolitis, regardless of the viruses involved. On the basis of these findings, we suggest that room sharing of patients with bronchiolitis is safe.

Distribution and relevance of Dientamoeba fragilis and Blastocystis species in gastroenteritis: results from a case-control study

The actual role of Dientamoeba fragilis and Blastocystis in patients with gastrointestinal symptoms is still under debate. A multicenter case-control study was performed in The Netherlands to elucidate the clinical relevance of molecular diagnostics results in gastroenteritis (GE). Samples from this case-control study were used to perform a detailed analysis on the presence of D. fragilis and Blastocystis in relation to gastrointestinal symptoms. In the present study, a real-time PCR for Blastocystis was performed on 1374 case samples and 1026 control samples from the multicenter gastroenteritis case-control study previously tested for D. fragilis. Prevalence of both micro-organisms was highest in children under 20 years of age and lowest in the oldest age group. A significantly lower overall detection of D. fragilis and Blastocystis was found in cases (both 25.8%) as compared to controls (37.6% and 40.0%, respectively). The difference for D. fragilis was statistically significant for subjects above 20 years of age. For Blastocystis, the difference was statistically significant in all age groups, except in children less than 5 years of age. A negative relation between D. fragilis-positive cases and diarrhea was found in this study population. More GE symptoms were reported in cases without D. fragilis or Blastocystis. In the present study, prevalence of both D. fragilis and Blastocystis is lower in cases with gastroenteritic symptoms than in controls. Besides, in cases with D. fragilis or Blastocystis, no association is shown between any of the GE symptoms. Interestingly, this suggests that the presence of these protozoans may be considered characteristic of a healthy intestinal microbiome.

High Treatment Uptake in Human Immunodeficiency Virus/Hepatitis C Virus-Coinfected Patients After Unrestricted Access to Direct-Acting Antivirals in the Netherlands

Background

The Netherlands has provided unrestricted access to direct-acting antivirals (DAAs) since November 2015. We analyzed the nationwide hepatitis C virus (HCV) treatment uptake among patients coinfected with human immunodeficiency virus (HIV) and HCV.

Methods

Data were obtained from the ATHENA HIV observational cohort in which >98% of HIV-infected patients ever registered since 1998 are included. Patients were included if they ever had 1 positive HCV RNA result, did not have spontaneous clearance, and were known to still be in care. Treatment uptake and outcome were assessed. When patients were treated more than once, data were included from only the most recent treatment episode. Data were updated until February 2017. In addition, each treatment center was queried in April 2017 for a data update on DAA treatment and achieved sustained virological response.

Results

Of 23574 HIV-infected patients ever linked to care, 1471 HCV-coinfected patients (69% men who have sex with men, 15% persons who [formerly] injected drugs, and 15% with another HIV transmission route) fulfilled the inclusion criteria. Of these, 87% (1284 of 1471) had ever initiated HCV treatment between 2000 and 2017, 76% (1124 of 1471) had their HCV infection cured; DAA treatment results were pending in 6% (92 of 1471). Among men who have sex with men, 83% (844 of 1022) had their HCV infection cured, and DAA treatment results were pending in 6% (66 of 1022). Overall, 187 patients had never initiated treatment, DAAs had failed in 14, and a pegylated interferon-alfa-based regimen had failed in 54.

Conclusions

Fifteen months after unrestricted DAA availability the majority of HIV/HCV-coinfected patients in the Netherlands have their HCV infection cured (76%) or are awaiting DAA treatment results (6%). This rapid treatment scale-up may contribute to future HCV elimination among these patients.

Contact precautions in single-bed or multiple-bed rooms for patients with extended-spectrum β-lactamase-producing Enterobacteriaceae in Dutch hospitals: a cluster-randomised, crossover, non-inferiority study

BACKGROUND

Use of single-bed rooms for control of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae is under debate; the added value when applying contact precautions has not been shown. We aimed to assess whether an isolation strategy of contact precautions in a multiple-bed room was non-inferior to a strategy of contact precautions in a single-bed room for preventing transmission of ESBL-producing Enterobacteriaceae.

METHODS

We did a cluster-randomised, crossover, non-inferiority study on medical and surgical wards of 16 Dutch hospitals. During two consecutive study periods, either contact precautions in a single-bed room or contact precautions in a multiple-bed room were applied as the preferred isolation strategy for patients with ESBL-producing Enterobacteriaceae cultured from a routine clinical sample (index patients). Eligible index patients were aged 18 years or older, had no strict indication for barrier precautions in a single-bed room, had a culture result reported within 7 days of culture and before discharge, and had no wardmate known to be colonised or infected with an ESBL-producing Enterobacteriaceae isolate of the same bacterial species with a similar antibiogram. Hospitals were randomly assigned in a 1:1 ratio by computer to one of two sequences of isolation strategies, stratified by university or non-university hospital. Allocation was masked for laboratory technicians who assessed the outcomes but not for patients, treating doctors, and infection-control practitioners enrolling index patients. The primary outcome was transmission of ESBL-producing Enterobacteriaceae to wardmates, which was defined as rectal carriage of an ESBL-producing Enterobacteriaceae isolate that was clonally related to the index patient's isolate in at least one wardmate. The primary analysis was done in the per-protocol population, which included patients who were adherent to the assigned room type. A 10% non-inferiority margin for the risk difference was used to assess non-inferiority. This study is registered with Nederlands Trialregister, NTR2799.

FINDINGS

16 hospitals were randomised, eight to each sequence of isolation strategies. All hospitals randomised to the sequence single-bed room then multiple-bed room and five of eight hospitals randomised to the sequence multiple-bed room then single-bed room completed both study periods and were analysed. From April 24, 2011, to Feb 27, 2014, 1652 index patients and 12 875 wardmates were assessed for eligibility. Of those, 693 index patients and 9527 wardmates were enrolled and 463 index patients and 7093 wardmates were included in the per-protocol population. Transmission of ESBL-producing Enterobacteriaceae to at least one wardmate was identified for 11 (4%) of 275 index patients during the single-bed room strategy period and for 14 (7%) of 188 index patients during the multiple-bed room strategy period (crude risk difference 3·4%, 90% CI -0·3 to 7·1).

INTERPRETATION

For patients with ESBL-producing Enterobacteriaceae cultured from a routine clinical sample, an isolation strategy of contact precautions in a multiple-bed room was non-inferior to a strategy of contact precautions in a single-bed room for preventing transmission of ESBL-producing Enterobacteriaceae. Non-inferiority of the multiple-bed room strategy might change the current single-bed room preference for isolation of patients with ESBL-producing Enterobacteriaceae and, thus, broaden infection-control options for ESBL-producing Enterobacteriaceae in daily clinical practice.

FUNDING

Netherlands Organisation for Health Research and Development.

Efficacy of Pre-Operative Antimicrobial Prophylaxis in Patients Undergoing Pancreatoduodenectomy: A Multi-Center Retrospective Analysis

BACKGROUND

The most common complications after pancreaticoduodenectomy (PD) are infectious, despite the standard use of cefazolin and metronidazole prophylaxis. Pre-operative biliary drainage (PBD) is a well-known risk factor for infectious complications. The objective was to identify the pathogens in intra-operative bile cultures in patients undergoing PD-with and without PBD-to determine the optimal antimicrobial prophylaxis regimen.

PATIENTS AND METHODS

Patients who underwent PD between 2009 and 2016 were identified retrospectively in three major teaching hospitals in The Netherlands. Organisms isolated from intra-operative bile cultures were studied. If pathogen coverage by standard prophylaxis was incomplete, the most appropriate alternative regimen was determined.

RESULTS

Of this large cohort of 352 patients, 56% underwent PBD and 44% did not. Positive bile cultures were found in 87.9% in the PBD group, compared with 31.8% in the non-PBD group. The micro-organisms isolated most commonly were Enterococcus, Streptococcus, and Klebsiella species. Cefazolin and metronidazole were appropriate in only 71% of patients. Adding gentamicin would provide complete coverage in 99% of PBD and 100% of non-PBD patients.

CONCLUSIONS

Our data confirm that PBD prior to PD leads to microbial colonization and antibiotic resistance. To potentially prevent infectious complications, gentamicin may be added to the standard antimicrobial prophylaxis.

Epidemiology of Extended-Spectrum β-Lactamase-Producing E. coli and Vancomycin-Resistant Enterococci in the Northern Dutch-German Cross-Border Region

Objectives: To reveal the prevalence and epidemiology of extended-spectrum β-lactamase (ESBL)- and/or plasmid AmpC (pAmpC)- and carbapenemase (CP) producing Enterobacteriaceae and vancomycin-resistant enterococci (VRE) across the Northern Dutch–German border region.

Methods: A point-prevalence study on ESBL/pAmpC/CP producing Enterobacteriaceae and VRE was carried out in hospitalized patients in the Northern Netherlands (n = 445, 2012–2013) and Germany (n = 242, 2012). Healthy individuals from the Dutch community (n = 400, 2010–2012) were also screened. In addition, a genome-wide gene-by-gene approach was applied to study the epidemiology of ESBL-Escherichia coli and VRE.

Results: A total of 34 isolates from 27 patients (6.1%) admitted to Dutch hospitals were ESBL/pAmpC positive and 29 ESBL-E. coli, three pAmpC-E. coli, one ESBL-Enterobacter cloacae, and one pAmpC-Proteus mirabilis were found. In the German hospital, 18 isolates (16 E. coli and 2 Klebsiella pneumoniae) from 17 patients (7.7%) were ESBL positive. In isolates from the hospitalized patients CTX-M-15 was the most frequently detected ESBL-gene. In the Dutch community, 11 individuals (2.75%) were ESBL/pAmpC positive: 10 ESBL-E. coli (CTX-M-1 being the most prevalent gene) and one pAmpC E. coli. Six Dutch (1.3%) and four German (3.9%) hospitalized patients were colonized with VRE. Genetic relatedness by core genome multi-locus sequence typing (cgMLST) was found between two ESBL-E. coli isolates from Dutch and German cross-border hospitals and between VRE isolates from different hospitals within the same region.

Conclusion: The prevalence of ESBL/pAmpC-Enterobacteriaceae was similar in hospitalized patients across the Dutch–German border region, whereas VRE prevalence was slightly higher on the German side. The overall prevalence of the studied pathogens was lower in the community than in hospitals in the Northern Netherlands. Cross-border transmission of ESBL-E. coli and VRE seems unlikely based on cgMLST analysis, however continuous monitoring is necessary to control their spread and stay informed about their epidemiology.

Infectious Complications after Major Abdominal Cancer Surgery: In Search of Improvable Risk Factors

BACKGROUND

Major resections for esophageal, gastric, hepatic, pancreatic, and colorectal cancer continue to be associated with a high peri-operative morbidity of up to 30%-40%. To a large extent, this morbidity is caused by infectious complications that add up to a considerable burden to patients and hospital costs. The objective of this large retrospective cross-sectional study was to determine independent patient and operation-related risk factors for infectious complications after major abdominal cancer operations to elucidate how infection rates can be reduced and improve health-care quality.

PATIENTS AND METHODS

In 1,389 cancer patients who underwent a major resection procedure between 2009 and 2013, infectious complications and their independent determinants were analyzed by multivariable logistic regression (p < 0.05).

RESULTS

Male gender was a risk factor for infections in general, whereas patients ≥65 y (odds ratio [OR] 1.75; p = 0.008), urinary tract infection (OR 0.51; p = 0.004), American Society of Anesthesiologists score (OR 1.55; p = 0.004), overall (OR 1.70; p = 0.037), vascular (OR 1.59; p = 0.020), and neurologic comorbidity (OR 2.22; p = 0.001) were associated significantly with pneumonia. Intra-abdominal drainage (OR 1.41; p = 0.024) and a duration of surgery of ≥180 min (OR 1.85; p = 0.001) were risk factors for surgical site infections. Total parenteral nutrition was significantly associated with intravascular catheter-induced infections (OR 18.09; p < 0.001) and sepsis (OR 6.69; p < 0.001).

CONCLUSIONS

In this study, several independent risk factors for infectious complications in major abdominal cancer operations were identified, providing opportunities for further reducing peri-operative infections. General awareness and focus on preventing infectious complications may have a significant impact on health-care outcomes and costs.

Co-infections in children hospitalised for bronchiolitis: role of roomsharing

BACKGROUND

Bronchiolitis is a major cause for hospitalisation in young children during the winter season, with respiratory syncytial virus (RSV) as the main causative virus. Apart from standard hygiene measures, cohorting of RSV-infected patients separately from RSV-negative patients is frequently applied to prevent cross-infection, although evidence to support this practice is lacking. The objective is to evaluate the risk of room sharing between RSV-positive and RSV-negative patients.

METHODS

We performed a prospective observational cohort study in children < 2 years hospitalised with acute bronchiolitis. During the first day of admission, patients shared one room, pending results of virological diagnosis (PCR). When diagnostic results were available, RSV-positive and RSV-negative patients were separated. Standard hygienic measures (gowns, gloves, masks, hand washing) were used in all patients.

RESULTS

We included 48 patients (83% RSV-positive). Co-infection was found in nine patients at admission, and two during hospitalisation (23%). The two patients with acquired co-infection had been nursed in a single room during the entire admission. None of 37 patients sharing a room with other bronchiolitis patients (20 with patients with a different virus) were co-infected during admission. Disease severity in co-infection was not worse than in mono-infection.

CONCLUSION

One in five patients with bronchiolitis was co-infected, but co-infection acquired during admission was rare and was not associated with more severe disease. Room sharing between RSV-positive and RSV-negative patients (on the first day of admission) did not influence the risk of co-infection, suggesting that cohorting of RSV-infected patients separate from non-RSV-infected patients may not be indicated.

Otitis externa following aural irrigation linked to instruments contaminated with Pseudomonas aeruginosa

BACKGROUND

The incidence of acute otitis externa, an infection of the external auditory canal, in general practitioners' (GP) practices in The Netherlands is about 14 per 1000 patients per year. In early 2010, one of the authors noted that some of the otitis externa patients in his GP practice had undergone cerumen removal by ear syringing a few weeks earlier. Bacterial cultures of samples taken from the instruments used showed contamination of an ear syringe by Pseudomonas aeruginosa. From then on, P. aeruginosa isolates from patients' ears were stored in the laboratory.

AIM

It was assessed whether cross-contamination with P. aeruginosa between patients in the same GP practice could occur through the use of contaminated ear lavage instruments.

METHODS

From 17 GP practices, the otolaryngology Outpatient Department and the Out-of-Hours GP Service, instruments used for examining and cleaning the outer ear were swabbed. Strains of P. aeruginosa cultured from the instruments were genotyped together with isolates of patients registered in the same practice.

FINDINGS

In four practices where contaminated instruments were found, genotyping showed similarity between P. aeruginosa strains isolated from a patient and the ear syringe, and/or between strains of different patients in the same practice.

CONCLUSIONS

Transmission of P. aeruginosa from ear lavage instruments to patients appears to occur with otitis externa as a result. Together with the Infection Control Unit of our hospital we have formulated recommendations for the appropriate cleaning, disinfection and storage of re-usable ear lavage instruments for the GP practices to implement.

[Should all dermatologists still be considered 'dermato-venereologists' in the year 2013?]

This commentary primarily focuses on the appropriateness of the predicate 'venereologist' for dermatologists in the Netherlands. If the quantity of care delivered were to be the most important factor needed for the qualification 'venereologist', the answer to the title question would undoubtedly be 'no' because more than 70% of sexually transmitted disease (STD) care is delivered in primary care centres. After the reorganisation of STD care in the Netherlands in 2006, 8 coordinating municipal STD centres were allocated for the primary care of pre-defined risk groups. By utilizing multidisciplinary guidelines, the Dutch Society of Dermatologists and Venereologists plays an important coordinating and supervisory role in current primary and in-hospital STD care.

[A man with neutropenic fever]

A 43-year-old patient with recurrent acute myeloid leukemia (AML) was treated with high-dose cytarabine. After two weeks of neutropenic fever, multiple cutaneous nodules appeared. Histopathological examination of a skin biopsy showed a mycosis and Fusarium solani was cultured. Despite antimycotic therapy, the patient died due to complications of his AML treatment.

Does electronic clinical microbiology results reporting influence medical decision making: a pre- and post-interview study of medical specialists

Background

Clinicians view the accuracy of test results and the turnaround time as the two most important service aspects of the clinical microbiology laboratory. Because of the time needed for the culturing of infectious agents, final hardcopy culture results will often be available too late to have a significant impact on early antimicrobial therapy decisions, vital in infectious disease management. The clinical microbiologist therefore reports to the clinician clinically relevant preliminary results at any moment during the diagnostic process, mostly by telephone. Telephone reporting is error prone, however. Electronic reporting of culture results instead of reporting on paper may shorten the turnaround time and may ensure correct communication of results. The purpose of this study was to assess the impact of the implementation of electronic reporting of final microbiology results on medical decision making.

Methods

In a pre- and post-interview study using a semi-structured design we asked medical specialists in our hospital about their use and appreciation of clinical microbiology results reporting before and after the implementation of an electronic reporting system.

Results

Electronic reporting was highly appreciated by all interviewed clinicians. Major advantages were reduction of hardcopy handling and the possibility to review results in relation to other patient data. Use and meaning of microbiology reports differ significantly between medical specialties. Most clinicians need preliminary results for therapy decisions quickly. Therefore, after the implementation of electronic reporting, telephone consultation between clinician and microbiologist remained the key means of communication.

Conclusions

Overall, electronic reporting increased the workflow efficiency of the medical specialists, but did not have an impact on their decision-making.

Comparison of two commercial molecular assays for simultaneous detection of respiratory viruses in clinical samples using two automatic electrophoresis detection systems

Two molecular assays were compared with real-time RT-PCR and viral culture for simultaneous detection of common viruses from respiratory samples: a multiplex ligation-dependant probe amplification (MLPA) and a dual priming oligonucleotide system (DPO). In addition, the positive detections of MLPA and DPO were identified using two different automatic electrophoresis systems. A panel of 168 culture-positive and negative samples was tested by the molecular assays for the presence of influenza A and B virus, respiratory syncytial virus, human metapneumovirus, rhinovirus, coronaviruses, parainfluenza viruses and adenovirus.

One hundred and twenty-nine (77%) samples were positive as detected by at least one method. Sixty-nine (41%) samples were positive by cell culture (excluding human metapneumovirus and coronaviruses), 116 (69%) by RT-PCR, 127 (76%) by MLPA and 100 (60%) by DPO. The MLPA yielded results in one attempt for all samples included while 12 (7.2%) samples had to be repeated by the DPO assay due to inconclusive results. The MLPA assay performed well in combination with either electrophoresis system, while the performance of the DPO assay was influenced by the electrophoresis systems.

Both molecular assays are comparable with real-time RT-PCR, more sensitive than viral culture and can detect dual infections easily. Results can be obtained within 1 day.

The need for European professional standards and the challenges facing clinical microbiology

Microorganisms spread across national boundaries and the professional activities of clinical (medical) microbiologists are critical in minimising their impact. Clinical microbiologists participate in many activities, e.g. diagnosis, antibiotic therapy, and there is a need for a set of professional standards for Europe with a common curriculum, to build upon the current strengths of the specialty and to facilitate the free movement of specialists within the European Union. Such standards will also better highlight the important contribution of clinical microbiologists to healthcare. There is a move to larger centralised microbiology laboratories often located off-site from an acute hospital, driven by the concentration of resources, amalgamation of services, outsourcing of diagnostics, automation, an explosion in the range of staff competencies and accreditation. Large off-site centralised microbiology laboratories are often distant to the patient and may not facilitate the early detection of microbial spread. Ultimately, the needs of patients and the public are paramount in deciding on the future direction of clinical microbiology. Potential conflicts between integration on an acute hospital site and centralisation can be resolved by a common set of professional standards and a team-based approach that puts patients first.

Parasitological diagnosis combining an internally controlled real-time PCR assay for the detection of four protozoa in stool samples with a testing algorithm for microscopy

Molecular detection of gastrointestinal protozoa is more sensitive and more specific than microscopy but, to date, has not routinely replaced time-consuming microscopic analysis. Two internally controlled real-time PCR assays for the combined detection of Entamoeba histolytica, Giardia lamblia, Cryptosporidium spp. and Dientamoeba fragilis in single faecal samples were compared with Triple Faeces Test (TFT) microscopy results from 397 patient samples. Additionally, an algorithm for complete parasitological diagnosis was created. Real-time PCR revealed 152 (38.3%) positive cases, 18 of which were double infections: one (0.3%) sample was positive for E. histolytica, 44 (11.1%) samples were positive for G. lamblia, 122 (30.7%) samples were positive for D. fragilis, and three (0.8%) samples were positive for Cryptosporidium. TFT microscopy yielded 96 (24.2%) positive cases, including five double infections: one sample was positive for E. histolytica/Entamoeba dispar, 29 (7.3%) samples were positive for G. lamblia, 69 (17.4%) samples were positive for D. fragilis, and two (0.5%) samples were positive for Cryptosporidium hominis/Cryptosporidium parvum. Retrospective analysis of the clinical patient information of 2887 TFT sets showed that eosinophilia, elevated IgE levels, adoption and travelling to (sub)tropical areas are predisposing factors for infection with non-protozoal gastrointestinal parasites. The proposed diagnostic algorithm includes application of real-time PCR to all samples, with the addition of microscopy on an unpreserved faecal sample in cases of a predisposing factor, or a repeat request for parasitological examination. Application of real-time PCR improved the diagnostic yield by 18%. A single stool sample is sufficient for complete parasitological diagnosis when an algorithm based on clinical information is applied.

[Gastroenteritis caused by Salmonella from pet snakes]

A Salmonella subspecies associated with reptiles (Salmonella enterica subspecies diarizonae) was isolated from the stool of a 19-year-old man with gastroenteritis. The same species was isolated from stool and urine samples taken from terraria found in the home of the patient's parents where snakes were kept. A high percentage of reptiles in the wild and in captivity are asymptomatic carriers of Salmonella species that can be transmitted to humans who come in contact with these animals. Unlike in the United States of America, for example, cases of reptile-associated infections have scarcely been published in the Netherlands and targeted information on the risk of infection is lacking. Because the popularity of exotic pets--and thereby the risk of infection--is increasing in The Netherlands, targeted information for veterinarians, traders and owners of exotic pets is warranted to prevent reptile-associated salmonellosis.

[A patient with serious viral myositis following flu]

A 16-year-old girl presented at the emergency unit with myalgia following a flu-like episode. Laboratory tests indicated severe rhabdomyolysis and nephritis. Autoimmune-induced myositis was excluded on the basis of negative tests for antinuclear antibodies; prednisolone treatment was discontinued 1 week later. The patient recovered gradually and was discharged with physiotherapy 2 weeks later. High positive titres of complement-binding antibody against influenza B virus were found, i.e. 1:125 and 1:250 on days to and 25 of illness, respectively. Viral myositis is an uncommon disease entity that occurs following a viral infection, especially with influenza virus, that has been experienced for the first time. It usually runs a benign course: children often present with calf tenderness that resolves within a few days. There are cases, however, with a more serious course involving severe rhabdomyolysis and acute renal failure that can be sometimes fatal.

The use of in-line intravenous filters in sick newborn infants

AIM

This study assesses the improvement in outcome for newborn infants by decreasing major complications associated with intravenous fluid therapy by using an in-line filter, and evaluates the economical impact this might have in relation to daily changing of i.v. lines.

METHODS

In a prospective controlled study, 88 infants were randomly assigned to receive either filtered (except for lipids, blood and blood products) or non-filtered infusions via a central catheter. Main outcome measures such as bacteraemia, phlebitis, extravasation, thrombosis, septicaemia and necrosis were all scored. The costs attributable to patients during a standard 8-day stay were also recorded.

RESULTS

Significant reductions were found in major complications such as thrombi and clinical sepsis (control group (21), filter group (8); p < 0.05). Bacterial cultures of the filters showed a contamination rate on the upstream surface of 15/109 filters (14%). The mean costs of disposables were less in the filter group, showing a reduction from 31.17 euros to 23.79 euros.

CONCLUSIONS

The use of this in-line filter leads to a significant decrease in major complications and substantial cost savings.

Identification and susceptibility testing of Enterobacteriaceae and Pseudomonas aeruginosa by direct inoculation from positive BACTEC blood culture bottles into Vitek 2

Inoculation of an automated system for rapid identification (ID) and antimicrobial susceptibility testing (AST) directly from positive blood culture bottles will reduce the turnaround time of laboratory diagnosis of septicemic patients, which benefits clinical outcome and decreases patient costs. Direct test results, however, must always be confirmed by testing a pure overnight culture, which is the "gold standard." We studied the accuracy of direct testing versus repeat testing in order to investigate the possibility of refraining from repeat testing. We also assessed the clinical risk of reporting results based on direct testing only. We inoculated Vitek 2 (bioMérieux) directly from 410 positive BACTEC 9240 (BD) blood culture bottles containing gram-negative rods and studied the ID and AST results. In a comparison of direct inoculation with the standard method, a total of 344 isolates of Enterobacteriaceae and Pseudomonas aeruginosa were tested, and 93.0% were correctly identified. Of the 39 (10.2%) samples that contained bacilli not identifiable by Vitek 2, only 1 gave a conclusive, correct result. The overall MIC agreement among 312 isolates was 99.2%, with 0.8% very major and 0.02% major error rates. Of only three (polymicrobial) samples, the direct susceptibility pattern would be reported to the clinician as too sensitive. Vitek 2 results obtained from direct inoculation of blood culture bottles containing gram-negative bacilli are safe enough for immediate reporting, provided that ID and AST are consistent. Repeat testing is not necessary, unless Gram stain or overnight subculture results raise doubt about the purity of the culture.

Detection of a nosocomial outbreak of salmonellosis may be delayed by application of a protocol for rejection of stool cultures

In October 2001 an outbreak of Salmonella enterica serovar enteritidis phage-type 6 occurred in a hospital and a nursing home, both served by the same hospital kitchen. Five nursing home residents died during the outbreak. S. enteritidis was isolated from three of them. Of 231 stool samples from nursing home residents, hospital patients and employees, 82 were culture-positive. All symptomatic patients were treated with oral ciprofloxacin. Inspection of the kitchen showed that during preparation of the desserts implicated in causing the outbreak, temperatures were not measured and storage temperatures were too high. No left-over food samples were available for analysis. According to the 'four-day rule' in use in this hospital, the stool samples related to the first outbreak were not cultured for Salmonella spp., whereas culturing afterwards from both stored specimens and repeats, showed that some of these samples would have been positive for S. enteritidis. Thus without the application of stool culture rejection criteria the outbreak would have been detected one day earlier. With the four-day rule in effect, the outbreak might have been detected much later, if an unusually high number of nursing home residents with gastroenteritis had not been noticed by nursing home physicians. The rule was revised to prevent a possible delay in the future. As a result of this outbreak, the government has announced legislation forbidding the sale of Salmonella-contaminated eggs. An official ban on the use of raw eggs will be included in several hygiene codes.