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.

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.

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.

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.

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.

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.

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.

Risk control of surgical site infection after cardiothoracic surgery.

The purpose of this prospective study was to investigate whether a risk control programme based on risk assessment, new treatment modalities and the presence of a surveillance programme reduces the incidence of surgical site infections (SSI). Between January 2001 and December 2003, 167 patients were treated for a total of 183 SSIs. Data were collected on pre-operative risk factors, intra-operative data and postoperative recovery, including complications, infecting organisms, SSI treatment techniques and length of hospital stay. In this series, the total incidence of SSI was 5.6%. The mean age of affected patients was 65.1 years with a range of 20-87 years. Mean intensive care and hospital stay for SSI was 3.6 days and 18.8 days, respectively. Total mortality was 4.8%. Many risk factors were encountered, some of which were associated with a high morbidity. The majority of SSIs were treated by topical negative pressure therapy (N=81), which gave few side-effects and good clinical results. After starting the surveillance programme, a steady decline in prevalence was observed from 8.9% to 3.9%. This series adds to the evidence that SSI after cardiothoracic surgery is a major but mainly preventable cause of morbidity and mortality. Risk factor assessment, application of novel treatment modalities and an adequate surveillance system all increased patient safety.

Trends in fungaemia and antifungal susceptibility in the Netherlands.

We retrospectively evaluated fungaemia over the period 1996 to 2001 in five university hospitals. Over 350,000 blood cultures were collected during more than 7 million days of hospitalisation. The average rate of fungaemia over the six-year period was 0.82 per 10,000 patient days (range 0.65 to 1.21 per 10,000 patient days). The proportion of bloodstream infections caused by Candida albicans remained stable throughout the study period with a mean of 53% (range 48 to 62%). This is a change from trends described in previous studies, including a survey performed in the Netherlands. This study shows a new, stable rate of fungaemia and no further signs of increasing rate of infections due to non-albicans Candida species. Susceptibility to all tested antifungal agents remained stable throughout the study period.

[Neonatal infection with Listeria monocytogenes: rare, but serious]. / Neonatale infectie met listeria monocytogenes: zeldzaam, maar ernstig.

Between 1993 and 2003, three infants, two girls and a boy, were found to have an invasive infection with Listeria monocytogenes. They received intensive care including respiratory and circulatory support, antibiotics, and treatment of the neurological complications when possible. One of the girls survived without sequelae but the other two infants died in the neonatal period. In one of these two cases there was a clear clue to the source of the infection in the dietary history of the mother: she had consumed unpasteurised cow's milk. The mothers ofthe infants that died had developed fever shortly before parturition. In The Netherlands, the incidence of neonatal invasive infection with Listeria is estimated at 1.3 per 100,000 live-born children per year. This figure seems not to have changed in the last 20 years. Because of the risk of this rare but serious infection, dietary advice to pregnant women to avoid possibly contaminated food is still relevant.

[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.

[Increase in the number of invasive Haemophilus influenzae type b infections]. / Toename van het aantal invasieve infecties door Haemophilus influenzae type b.

OBJECTIVE: To describe the increase of invasive Haemophilus influenzae type b (Hib) infections in The Netherlands before and after the introduction of Hib vaccination in 1993, and to hypothesise about possible explanations. DESIGN: Descriptive. METHOD: Data on the prevalence of invasive Hib infections, such as meningitis and epiglottitis, during 1990-2004 were obtained from The Netherlands Reference Laboratory for Bacterial Meningitis, which collects Hib isolates from spinal fluid and blood from across the country. RESULTS: The incidence of invasive Hib infections decreased substantially for a few years after 1993. The total number of isolates was at a minimum in 1999 (n = 12) and increased to 49 in 2004. The annual number of patients with vaccine failure was 5 or less during 1995-2001, but was between 10 and 15 from 2002 onwards. A definite explanation for the increase in the incidence of invasive Hib infections cannot be given. Improbable causes are a surveillance artefact, an impaired response to the vaccine due to vaccination-scheme changes or interaction with other vaccines, or selection of Hib variants that are less sensitive to the vaccine-induced immunity. It most likely involves secondary vaccine failure: Hib carriership is decreased by mass vaccination, whereupon natural boosting occurs less frequently later in life. Subsequently, immunity decreases and susceptibility to invasive infection increases. Careful surveillance of invasive Hib infections in The Netherlands remains important.

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.

Severity of enterocolitis is predicted by IL-8 in paediatric oncology patients.

Enterocolitis in oncology patients remains an important complication, but there is a lack of insight into its likely severity from microbial, pathological and inflammatory aspects. Paediatric oncology patients admitted with neutropenic fever, who developed abdominal pain and diarrhoea, were monitored by the takers of rectal biopsies, cultures, and inflammatory marker measurements. Twenty-five patients were included (mean age 7.1 years). 8 patients (32%) needed intensive care treatment, 3 (12%) patients died. Gram-positive bacteraemia was diagnosed in 4 patients (16%). Most patients had negative blood and stool cultures. Predictors of a severe clinical course of the enterocolitis were an increased serum interleukin-8 (IL-8) (>1000 pg/ml) level and an increased serum C-reactive protein level (CRP) (>150 mg/l) level, both measured on the first day of clinical illness. Relative risks (RR) for admission to an Intensive Care Unit (ICU) were 11.3 (95% Confidence Interval (CI) 1.6-77.9) for elevated IL-8 levels and 6.4 (95% (CI) 0.92-45.1) for increased CRP levels. Rectal biopsies and pathology could not predict outcome (P=0.22). IL-8 analysis at the onset of enterocolitis symptoms can identify high-risk patients, which might be used clinically to design future intervention trials.

Immunoglobulin A antibodies against Pseudomonas aeruginosa in the tear fluid of contact lens wearers.

PURPOSE: Pseudomonas aeruginosa is the most important cause of contact lens-associated ulcerative keratitis, especially for those who use extended-wear lenses. Until now, the presence of specific anti-P. aeruginosa immunoglobulin A (IgA) antibodies in the tears of contact lens wearers has not been investigated and is the purpose of the current study. METHODS: The levels of specific IgA antibodies against P. aeruginosa and total secretory IgA (s-IgA) concentrations were measured in tears of various groups of contact lens and non-contact lens wearers using enzyme-linked immunosorbent assays. Contact lens groups were divided into the following categories: daily-wear rigid gas-permeable lenses (n = 23), daily-wear soft lenses (n = 22), extended-wear soft lenses (n = 17), and non-contact lens wearers (n = 23). As a positive control group, we tested tears obtained from patients with cystic fibrosis (n = 5) because the respiratory tract of these persons often are colonized by P. aeruginosa. RESULTS: The percentage of nonresponders (< 15 U/ml) varied between 9% in daily-wear rigid gas-permeable contact lens users to 23% in daily-wear soft contact lens users. The percentage of nonresponders in controls was 13%. The frequency of nonresponders was not significantly different among the different groups tested. All patients with cystic fibrosis showed a very high anti-P. aeruginosa IgA response in their tears. When analyzing the mean anti-P. aeruginosa IgA response, a significantly lower level was found in extended-wear contact lens users (38 U/ml) compared to non-contact lens wearers (82 U/ml). Total s-IgA levels in the tears of the various groups tested were not significantly different. CONCLUSIONS: A substantial number of persons in the population of contact lens wearers tested lack detectable IgA antibodies against P. aeruginosa in their tears and may be susceptible to P. aeruginosa keratitis if the physiological condition of their cornea is compromised.

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.

Meningitis due to viridans streptococci in adults.

Seven patients are reported with meningitis due to viridans streptococci. These patients represented 5% of culture-proven cases of bacterial meningitis in adults participating in a prospective multicentre clinical trial evaluating the use of dexamethasone. Meningitis was iatrogenic in three patients: one patient had been treated with endoscopic sclerotherapy for oesophageal varices, and two patients had undergone thermocoagulation of the gasserian ganglion for trigeminal neuralgia in the previous days.

Value of detecting leukocytospermia in the diagnosis of genital tract infection in subfertile men.

OBJECTIVES: To evaluate whether detection of leukocytospermia in a routine semen analysis is of diagnostic value in selecting men with an "actual" microbial infection and to assess the association between leukocytospermia and a history of bacterial and viral infections. DESIGN: Prospective clinical study. SETTING: Infertility clinic at the Center for Reproductive Medicine, Academic Medical Center, Amsterdam, the Netherlands. PATIENT(S): One hundred eighty-four men among subfertile couples attending our infertility clinic. INTERVENTION(S): The number of leukocytes was assessed in three semen samples. Serologic tests were performed, as was transurethral culture after digital prostatic massage. MAIN OUTCOME MEASURE(S): Diagnosis of actual bacterial and viral infections in relation to seminal leukocyte concentrations. The association of a history of sexually transmitted diseases with seminal leukocyte concentration. RESULT(S): An actual bacterial infection was present in 39% of men, and 11% of men had an actual viral infection. The area under the receiver operating curve, which was used to determine whether detection of leukocytospermia was of diagnostic value in identifying men with actual bacterial or viral infections, was 0.55 and 0.56 for bacterial and viral infection, respectively. A past infection with N. gonorrhoeae was associated with the presence of leukocytospermia. A past viral infection was not associated with leukocytospermia. CONCLUSION(S): Detection of leukocytospermia appears to be of no diagnostic value for selection of men with actual microbial infections, but leukocytospermia is associated with a history of gonorrhea.

Long-term prognosis in patients treated for erythema chronicum migrans and acrodermatitis chronica atrophicans.

OBJECTIVE: To determine whether Lyme borreliosis persisted or had recurred in patients treated for erythema chronicum migrans and acrodermatitis chronica atrophicans. DESIGN: Retrospective follow-up study. Mean time between treatment and follow-up study was 8.8 years (SD, 66.6 years). SETTING: Department of dermatology. PATIENTS: Patients (N = 52) treated from July 1964 to October 1992 for erythema chronicum migrans (ECM; n = 44) or acrodermatitis chronica atrophicans (ACA; n = 8). Fifty-two of the 56 successfully contacted and registered patients agreed to participate, for a response rate of 93%. MAIN OUTCOME MEASURES: Signs and symptoms of Lyme borreliosis; serum antibodies to Borrelia burgdorferi. RESULTS: The interval from the time of diagnosis to study entry was 0.8 to 28.7 years (mean, 8.2 years). No symptoms or signs of active Lyme borreliosis were observed in the 52 patients. Antibodies to B burgdorferi were found in the ECM group in 1 of the 23 patients who received a recommended treatment and 2 of the 21 patients who received other treatments; antibodies were found in the ACA group in all 5 adequately treated patients who received a recommended treatment and in 1 of the 3 patients who received other treatments. CONCLUSIONS: There was no association between serologic results and type of treatment or between serologic results and complaints or symptoms at the time of the study in either of the patient groups. The prognosis in most patients with Lyme borreliosis is excellent.