Risk factors for sporadic listeriosis in the Netherlands, 2008 to 2013.

Although the disease burden of listeriosis on population level is low, on individual level the impact is high, largely due to severe illness and a high case fatality. Identification of risk factors supports and specifies public health actions needed for prevention. We performed a case­control study to determine host- and food-related risk factors for non-perinatal listeriosis in the Netherlands. Patients with non-perinatal listeriosis reported between July 2008 and December 2013 were compared with controls from a periodic control survey who completed a questionnaire in the same period. Higher age, male sex, underlying disease, especially cancer and kidney disease, and use of immunosuppressive medicine were strong risk factors for acquiring non-perinatal listeriosis. Analysis of the food consumption in the group of cases and controls with underlying diseases did not reveal any high-risk food products. Information and advice should continue to be given to persons at risk of severe listeriosis. Univariate analyses indicate that patients using gastric acid inhibitors are at risk. It is worth adding these patients to the group of susceptible persons.

Ticking the right boxes: classification of patients suspected of Lyme borreliosis at an academic referral center in the Netherlands.

To provide better care for patients suspected of having Lyme borreliosis (LB) we founded the Amsterdam Multidisciplinary Lyme borreliosis Center (AMLC). The AMLC reflects a collaborative effort of the departments of internal medicine/infectious diseases, rheumatology, neurology, dermatology, medical microbiology and psychiatry. In a retrospective case series, characteristics of 200 adult patients referred to the AMLC were recorded, and patients were classified as having LB, post-treatment LB syndrome (PTLBS), persistent Borrelia burgdorferi sensu lato (s.l.) infection despite antibiotic treatment or no LB. In addition, LB, PTLBS and persistent B. burgdorferi s.l. infection cases were classified as 'definite,' 'probable' or 'questionable.' Of the 200 patients, 120 (60%) did not have LB and 31 (16%) had a form of localized or disseminated LB, of which 12 were classified as definite, six as probable and 13 as questionable. In addition, 34 patients (17%) were diagnosed with PTLBS, of which 22 (11%) were probable and 12 (6%) questionable. A total of 15 patients (8%) were diagnosed with persistent B. burgdorferi s.l. infection, of which none was classified as definite, three as probable and 12 as questionable. In conclusion, in line with previous studies, the number of definite and probable (persisting) LB cases was low. The overall high number of questionable cases illustrates the fact that it can sometimes be challenging to either rule out or demonstrate an association with a B. burgdorferi s.l. infection, even in an academic setting. Finally, we were able to establish alternative diagnoses in a large proportion of patients.

Fusobacterium necrophorum, an emerging pathogen of otogenic and paranasal infections?

Fusobacterium necrophorum is a rare causative agent of otitis and sinusitis. Most commonly known is the classic Lemièrre's syndrome of postanginal sepsis with suppurative thrombophlebitis of the jugular vein. We report five patients diagnosed recently with a complicated infection with F. necrophorum originating from otitis or sinusitis. Two patients recovered completely, one patient died due to complications of the infection, one patient retained a slight hemiparesis and one patient had permanent hearing loss. Diagnosis and management are discussed. A possible factor in the emergence of F. necrophorum is proposed.

Unsuccessful validation of 2004 model for predicting academic or behavioural limitations after childhood bacterial meningitis.

AIM: In 2004, a model identifying children at risk of academic or behavioural limitations after bacterial meningitis (BM) was presented. Risk factors were male gender, low birthweight, lower educational level of the father, Streptococcus pneumoniae, lower cerebrospinal fluid (CSF) leucocyte count, delay between admission and start of antibiotics, dexamethasone <2 days, seizures and prolonged fever. The aim of this study was to validate that prediction model in an independent cohort. METHODS: Academic or behavioural limitations were determined in 93 Dutch school-age BM survivors. Risk factors for limitations were obtained from medical files. Validation was performed by applying the model in the cohort, then assessing discrimination and goodness of fit. Multiple imputation techniques were used to deal with missing values. RESULTS: Although fit of the model appeared good when it came to similarity of expected and observed cases (p-value of the Hosmer-Lemeshow test 0.24-0.57), discrimination was poor. Area under the curve (AUC) of the receiver operated characteristics (ROC) curve of the model was 0.83 (95% CI: 0.77-0.89) in the development cohort and 0.53 (95% CI: 0.41-0.65) in the validation cohort. CONCLUSION: External validation of the model was unsuccessful. It is not suitable for implementation in practice.

Fatal outcome of Bacillus cereus septicaemia.

Bacillus cereus is a ubiquitous environmental micro-organism which is often a contaminant of clinical cultures. Infections due to B. cereus are described, but mostly in immunocompromised patients. We report a fatal outcome of B. cereus septicaemia in an immunocompetent patient with a mechanical mitral valve.

The additional value of blood culture bottles in the diagnosis of endophthalmitis.

PURPOSE: To assess the additional value of blood culture bottles (BCBs) in the diagnosis of endophthalmitis by comparing its culture yield with that of conventional media (CM). DESIGN: Retrospective consecutive case series. METHODS: We included patients who were treated between January 2001 and January 2010 for clinically suspected endophthalmitis of any etiology, and had vitreous specimens cultivated in both BCB and CM. RESULTS: Specimens from 85 eyes from 85 patients were included. The culture yield of BCB was 69%, and that of CM was 72% (difference not significant). Adding the results of BCB improved the yield of CM significantly by 13%, resulting in a combined yield of 81%. The sensitivity of detection of Haemophilus influenzae in BCB seemed lower compared with CM, possibly due to the lack of growth factors in the BCB. There was no difference in yield between specimens obtained by tap or by vitrectomy. CONCLUSION: In contrast with earlier reports, we did not find BCB superior to CM. The combined use of BCB and CM increased the pathogen detection rate significantly and should therefore be considered as the microbiological method of choice in the work-up of endophthalmitis.

Highly resistant gram-negative microorganisms: incidence density and occurrence of nosocomial transmission (TRIANGLe Study).

OBJECTIVES: The objectives of this study were to determine the incidence density and the occurrence of horizontal spread of highly resistant gram-negative rods (HR-GNRs) in Dutch hospitals. The factors that influence these outcome measures were also investigated. METHODS: All patients with HR-GNRs, as determined by sample testing, who were hospitalized in 1 of 18 hospitals during a 6-month period (April through October 2007) were included in this study. For all available isolates, the species was identified, susceptibility was determined (including the presence of extended-spectrum ß-lactamases [ESBLs]), and molecular typing was performed. On the basis of a combination of species identification, molecular typing, and epidemiological data, the occurrence of nosocomial transmission was determined. RESULTS: The mean incidence density of patients with HR-GNRs was 55 per 100,000 patient-days (cumulative incidence, 39 per 10,000 patients admitted). A facility being a university hospital was a statistically significant (P = .03) independent determinant of a higher incidence of patients with HR-GNRs. The majority of HR-GNR isolates were ESBL producers. The adjusted transmission index-the ratio between secondary and primary cases-in the participating hospitals ranged from 0.0 to 0.2. The overall adjusted transmission index of HR-GNRs was 0.07. No determinants for a higher transmission index were identified. DISCUSSION: The nosocomial transmission rate of HR-GNRs was relatively low in all hospitals where well-established transmission-based precautions were used. The incidence density of patients with HR-GNRs was higher in university hospitals, probably due to the patient population and the complexity of the care provided.

Nationwide implementation of adjunctive dexamethasone therapy for pneumococcal meningitis.

BACKGROUND: In this nationwide prospective cohort study, we evaluated the implementation of adjunctive dexamethasone therapy in Dutch adults with pneumococcal meningitis. METHODS: From March 2006 through January 2009, all Dutch patients over 16 years old with community-acquired pneumococcal meningitis were prospectively evaluated. Outcome was classified as unfavorable (defined by a Glasgow Outcome Scale score of 1 to 4 points at discharge) or favorable (a score of 5). Clinical characteristics and outcome were compared with a similar nationwide cohort of 352 patients with pneumococcal meningitis from a previous period before guidelines recommended dexamethasone therapy (1998-2002). A multivariable prognostic model was used to adjust for differences in case mix between the 2 cohorts. RESULTS: We evaluated 357 episodes with pneumococcal meningitis in 2006-2009. Characteristics on admission were comparable with the earlier cohort (1998-2002). Dexamethasone was started with or before the first dose of antibiotics in 84% of episodes in 2006-2009 and 3% in 1998-2002. At discharge, unfavorable outcome was present in 39% in 2006-2009 and 50% in 1998-2002 (odds ratio [OR] 0.63; 95% confidence interval [CI] 0.46-0.86; p = 0.002). Rates of death (20% vs 30%; p = 0.001) and hearing loss (12% vs 22%; p = 0.001) were lower in 2006-2009. Differences in outcome remained after adjusting for differences in case mix between cohorts. CONCLUSIONS: Dexamethasone therapy has been implemented on a large scale as adjunctive treatment of adults with pneumococcal meningitis in the Netherlands. The prognosis of pneumococcal meningitis on a national level has substantially improved after the introduction of adjunctive dexamethasone therapy. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that dexamethasone (10 mg IV, given every 6 hours for 4 days started before or with the first dose of parenteral antibiotics) reduced the proportion of patients with unfavorable outcomes (Glasgow Outcome Scale score of 1 to 4) in the 2006-2009 cohort, as compared to the 1998-2002 cohort (39% vs 50%; OR 0.63; 95% CI 0.46-0.86; p = 0.002). Mortality rate (20% vs 30%; absolute risk difference 10%; 95% CI 4%-17%; p = 0.001) was also lower in 2006-2009.

Kytococcus schroeteri pneumonia in two patients with a hematological malignancy.

Neutropenic patients are susceptible to infections with usually harmless microorganisms. We report two cases of severe pneumonia in hematological patients due to Kytococcus schroeteri, a saprophyte of the human skin. When blood cultures or respiratory specimens yield micrococcus-like colonies, Kytococcus species, which are often resistant to penicillin, should be considered and the antimicrobial therapy should be adjusted accordingly.

Pre-admission clinical course of meningococcal disease and opportunities for the earlier start of appropriate intervention: a prospective epidemiological study on 752 patients in the Netherlands, 2003-2005.

To improve the timeliness of health care delivery to patients with meningococcal disease, the early disease evolution and clinical manifestation at admission were studied in all 752 patients with invasive meningococcal disease in the Netherlands in 2003-2005. Eighty-eight percent (88%) had serogroup B disease. The case fatality rate (CFR) was 6.7% overall, but reached 16% among adults over 50 years of age. The CFR was similar for serogroups B (6.3%) and C (5.2%). Admission followed 17 h (median) after the onset of symptoms. The CFR in patients admitted within 12 h, 12-18 h, 18-36 h or >36 h after the first symptoms was 10.2, 7.8, 3.5 and 2.2%, respectively. Only 60% of patients had skin lesions, and admission followed 2 h (median) later. Earlier recognition can be achieved when non-petechial clues are included in the diagnosis. A short duration of disease before admission is a simple tool in the recognition of patients with severe disease.

Seizures in adults with bacterial meningitis.

OBJECTIVE: To evaluate the occurrence and prognostic relevance of seizures in adults with community-acquired bacterial meningitis. METHODS: An observational cross-sectional study, in which patients with seizures are selected from a prospective nationwide cohort of 696 episodes of community-acquired bacterial meningitis, confirmed by culture of CSF in patients aged >16 years. We retrospectively collected data on EEGs. RESULTS: Seizures occurred in 121 of 696 episodes (17%). Death occurred in 41% of patients with seizures compared to 16% of patients without seizures (p < 0.001). The median number of seizures was 2 (interquartile range [IQR] 1 to 4). The median time between admission and the first seizure was 1 day (IQR 0 to 3). Patients with in-hospital seizures were more likely to have a CSF leukocyte count below 1,000 cells/mm(3) (36% vs 25%; p = 0.01), had higher median CSF protein levels (4.8 g/L [IQR 3.4 to 7.6] vs 4.1 g/L [IQR 2.1 to 6.8]), and higher median erythrocyte sedimentation rate (46 mm/hour [IQR 31 to 72] vs 36 mm/hour [IQR 18 to 69]; p = 0.02) than patients without in-hospital seizures. Focal cerebral abnormalities developed more often in patients with in-hospital seizures than in those without (41% vs 14%; p < 0.001). In a multivariate analysis, seizures were significantly more likely in patients with predisposing conditions, tachycardia, a low Glasgow Coma Scale score on admission, infection with Streptococcus pneumoniae, and focal cerebral abnormalities. Neuroimaging was performed on admission in 70% of episodes with prehospital seizures, with CT revealing a focal lesion in 32% of those episodes. Antiepileptic drugs were administered in 82% of patients with seizures and EEG was performed in 31% of episodes; a status epilepticus was recorded in five patients. CONCLUSIONS: Seizures occur frequently in adults with community-acquired bacterial meningitis. Seizures are associated with severe CNS and systemic inflammation, structural CNS lesions, pneumococcal meningitis, and predisposing conditions. The high associated mortality rate warrants a low threshold for starting anticonvulsant therapy in those with clinical suspicion of a seizure.

Nosocomial bacterial meningitis in adults: a prospective series of 50 cases.

In order to evaluate characteristics of nosocomial meningitis in adults, we performed a prospective cohort study of 50 episodes of nosocomial bacterial meningitis. These cases were confirmed by culture of cerebrospinal fluid (CSF) in patients aged >16 years. Classic symptoms of bacterial meningitis (headache, neck stiffness and fever) were present in >70% of the episodes, although only a minority (41%) presented with impairment of consciousness. Underlying conditions, such as a history of neurosurgery, recent head injury, CSF leakage or a distant focus of infection, were present in 94% of the episodes. Staphylococcus aureus was the most common pathogen in patients with a history of neurosurgery, causing 10 of 32 episodes (31%). Patients with a distant focus of infection, such as otitis, sinusitis or pneumonia were more likely to have meningitis due to Streptococcus pneumoniae than patients without [six of nine episodes (67%) vs seven of 41 (17%); P=0.01]. Complications occurred in 50% of the episodes and 16% of the patients died. Our study confirms that adults with nosocomial meningitis are a distinct patient group with specific bacterial pathogens, as compared to those with community-acquired bacterial meningitis. Underlying conditions, especially a history of neurosurgery or a distant focus of infection, were present in the large majority of patients, and mortality and morbidity rates were high.

Identification of genotypically diverse Cryptococcus neoformans and Cryptococcus gattii isolates by Luminex xMAP technology.

A Luminex suspension array, which had been developed for identification of Cryptococcus neoformans and Cryptococcus gattii isolates, was tested by genotyping a set of 58 mostly clinical isolates. All genotypes of C. neoformans and C. gattii were included. In addition, cerebrospinal fluid (CSF) obtained from patients with cryptococcal meningitis was used to investigate the feasibility of the technique for identification of the infecting strain. The suspension array correctly identified haploid isolates in all cases. Furthermore, hybrid isolates possessing two alleles of the Luminex probe region could be identified as hybrids. In CSF specimens, the genotype of the cryptococcal strains responsible for infection could be identified after optimization of the PCR conditions. However, further optimization of the DNA extraction protocol is needed to enhance the usability of the method in clinical practice.

Community-acquired Haemophilus influenzae meningitis in adults.

Haemophilus influenzae is an uncommon cause of bacterial meningitis in adults. This report describes a prospective evaluation of 16 episodes of community-acquired H. influenzae meningitis in a nationwide study on bacterial meningitis. Predisposing conditions were present in eight (50%) of the 16 episodes; the most common predisposing conditions were otitis or sinusitis (five episodes; 31%) and remote neurosurgery or head trauma (three episodes; 19%). One (6%) episode was fatal and hearing loss occurred in four (25%) episodes. It was concluded that H. influenzae meningitis in adults is a disease with a rather benign clinical course and a relatively good prognosis compared with pneumococcal meningitis.

Hyponatraemia in adults with community-acquired bacterial meningitis.

BACKGROUND: Hyponatraemia in adults with bacterial meningitis has been described as a common complication, but its true prevalence and clinical importance are unknown. AIM: To investigate the prevalence, clinical characteristics and consequences of hyponatraemia in bacterial meningitis in adults. DESIGN: Nationwide observational cohort study. METHODS: We prospectively assessed the prevalence and clinical characteristics of hyponatraemia among 696 adults with community-acquired bacterial meningitis. Symptoms and signs on admission, blood and CSF test results, radiological examinations and complications during admission were recorded. RESULTS: Sodium levels were determined at admission in 685/696 episodes of bacterial meningitis (98%). Hyponatraemia (<135 mmol/l) was seen in 208/685 (30%) and was classified as severe (<130 mmol/l) in 38 (6%). Hyponatraemia developed during admission in an additional 53 episodes. Hyponatraemia was not associated with an increase in symptoms, with complications or with unfavourable outcome. Treatment for hyponatraemia was initiated in 16% of episodes, but did not influence its duration. DISCUSSION: Hyponatraemia appears both common and benign in adults with bacterial meningitis. In cases of severe hyponatraemia, we suggest the use of fluid maintenance therapy.

[Two adult patients with pneumococcal peritonitis]. / Twee volwassen patiënten met pneumokokkenperitonitis.

Two women, aged 31 and 37 years, had abdominal pain and fever several months after giving birth and a few weeks after receiving an intrauterine device. Both patients were admitted and treated under the working diagnosis of pelvic inflammatory disease (PID). They appeared to have pneumococcal adnexitis and pneumococcal peritonitis. Both patients recovered after initiating directed antibiotic treatment. Peritonitis in previously healthy adults is seldom caused by pneumococci. Standard antibiotics that are effective when given empirically for PID may be a suboptimal treatment for pneumococcal peritonitis.

Epidemiology of multiple Acinetobacter outbreaks in The Netherlands during the period 1999-2001.

An increase in the number of outbreaks of Acinetobacter infection was notified in The Netherlands during 1999-2001. The present study compared the outbreaks at the species and strain levels, and analysed the epidemiology and control measures at the different locations. For each institute, three representative isolates from three patients were identified to the species and strain levels by genotyping methods. A questionnaire investigated the impact of the outbreak, the control measures that were taken, and the possible effects of the measures. Seven outbreaks were associated with Acinetobacter baumannii (three outbreaks with a strain designated strain A, two outbreaks with a strain designated strain B, and one outbreak each with strains designated C and D). An additional outbreak was caused by genomic species 13TU, which is related closely to A. baumannii. Strains B and D were identified as European clones III and II, respectively. Except for two hospitals with outbreaks caused by strain A, there was no known epidemiological link between the participating hospitals. In all hospitals the outbreak occurred on one or several intensive care units, and spread to other departments was noted in two hospitals. The number of patients affected ranged from six to 66 over a period of 2-22 months. In most outbreaks, patients were the likely reservoir from which spread occurred. In all hospitals, a large panel of measures was required to bring the outbreak to an end. Extensive environmental sampling yielded numerous positive samples in most but not all hospitals.

Widely distributed and predominant CTX-M extended-spectrum beta-lactamases in Amsterdam, The Netherlands.

Three hundred sixty Enterobacteriaceae and nonfermenting gram-negative bacilli, isolated during one week in May 2004 at five hospitals in Amsterdam, The Netherlands, were evaluated for the presence of extended-spectrum beta-lactamases (ESBLs). A prevalence of 7.8% was found, in contrast to the 1% observed in 1997. CTX-M ESBLs dominated, and four types were identified in 18 isolates.