Clinical characteristics and prognosis of pediatric Listeria monocytogenes meningitis based on 10-year data from a large children's hospital in China.

This study aims to summarize the clinical characteristics and prognosis of Listeria monocytogenes (LM) meningitis in children in Chongqing, China. A retrospective analysis of the clinical data and follow-up results of 20 LM meningitis patients admitted to the Children's Hospital of Chongqing Medical University (CHCMU) from January 2012 to December 2022 was performed. The LM meningitis incidence rate was between 0 and 14.3 per 100,000 persons. The median age at onset was 8.98 months. There were five neonate cases, which all had perinatal abnormalities. Seven non-neonatal cases (7/15, 46.7%) had a documented history of contaminated food intake. One case had primary immunodeficiency. The most common symptoms were fever (20/20), altered consciousness (19/20), and vomiting (15/20). Seven cases had seizures, eight cases had cranial nerve involvement, eight cases had positive Babinski sign, and 10 cases had positive meningeal signs. The most common complications were hyponatremia (6/20), hypokalemia (6/20), respiratory failure (5/20), subdural effusion (3/20), and hydrocephalus (2/20). Treatment primarily involved monotherapy or combination therapy with meropenem (15/20) and ampicillin (10/20). Fifteen cases were treated with monotherapy or combination therapy using vancomycin. Twelve cases were successfully followed up from 10 months to 9 years and 6 months, and all had favorable long-term outcomes. LM meningitis incidence in children is low and with nonspecific clinical manifestations. Strengthening food hygiene and safety education, and avoiding infections during pregnancy are important to prevent LM infection in neonates and high-risk individuals. Meropenem and ampicillin are the preferred treatments. Early diagnosis and treatment can improve prognosis.IMPORTANCEThe incidence of LM meningitis is extremely low, and there is currently no standardized treatment. We conducted a retrospective analysis of ten years of data from CHCMU regarding diagnosed LM meningitis cases, aiming to provide clinical evidence for the diagnosis and treatment.

Characteristics and Outcomes of Neonates With Blood Stream Infection Due to Listeria monocytogenes.

BACKGROUND: Infection due to Listeria monocytogenes (LM) is rare in neonates; thus, its clinical presentation and outcomes are not commonly reported, especially in low- and middle-income countries. In 2017, South Africa had an outbreak due to LM. OBJECTIVE: To determine demographic characteristics, clinical and laboratory findings and outcomes of all neonates infected with LM during the outbreak period. METHODS: This is a retrospective analytic study. Clinical and laboratory records of neonates admitted at Chris Hani Baragwanath Academic Hospital from January 2017 to May 2018 with positive blood and cerebrospinal fluid culture with LM were reviewed for demographic characteristics, clinical presentation, ancillary laboratory test results and outcomes at hospital discharge. RESULTS: There were 42 neonates with positive cultures due to LM. Thirty-four (81%) were born preterm. Mode of delivery was vaginal in 78.6% and 31.0% were HIV exposed. All patients presented within the first 6 days of life as an early-onset disease. Common clinical presentation was respiratory depression (52.4%) and respiratory distress (38.1%) with 69% requiring invasive or noninvasive respiratory support. Common abnormal laboratory findings were high C-reactive protein (77.1%) followed by leukopenia (23.8%). Fourteen patients (40%) had features of meningitis based on blood and cerebrospinal fluid findings (4 culture proven). There were 11 deaths at hospital discharge, giving a mortality rate of 26.2%. CONCLUSIONS: The majority of neonates infected with LM were born preterm, raising the possibility that LM itself may have been responsible for preterm labor. All presented in the first 6 days of life and most presented with respiratory distress or depression. A high proportion had meningitis, and there was a high-mortality overall.

Etiology, clinical presentation, outcome and the effect of initial management in immunocompromised patients with community acquired bacterial meningitis.

OBJECTIVES: The aim was to analyze differences in clinical presentation, etiology, management, and outcome between immunocompromised and immunocompetent patients with acute bacterial meningitis (ABM). METHODS: Data were extracted from 1056 adult ABM patients prospectively registered in the national Swedish quality register for ABM during 2008-2017. Primary endpoint was 30-day mortality and secondary endpoints 90-day mortality and unfavorable outcome. RESULTS: An immunocompromised state was observed in 352 (33%) of the 1056 patients. Streptococcus pneumoniae dominated in both immunocompromised and immunocompetent patients (53% in both groups), whereas L monocytogenes occurred in 11% and 2%, respectively. The unadjusted odds ratio (OR) for 30-day mortality in immunocompromised compared to immunocompetent patients was 1.68 (95% confidence interval (CI): 1.07-2.63). Adjusted for age, sex, and mental status on admission the OR was 1.34 (CI: 0.82-2.21). Adjusted also for time to antibiotic treatment and corticosteroids the OR was 1.10 (CI: 0.59-2.05), and in patients without Listeria meningitis 0.98 (CI: 0.50-1.90). Although, the ORs were higher for 90-day mortality and unfavorable outcome the effects of adjustments were similar. CONCLUSION: Mortality in immunocompromised patients with ABM is only moderately increased unless caused by Listeria. This difference is further reduced in patients given early antibiotic treatment and adjunctive corticosteroids. FUNDING: This work was supported by Stockholm County Council.

High incidence of severe neurological manifestations and high mortality rate for adult Listeria monocytogenes meningitis in Taiwan.

The clinical characteristics and therapeutic outcomes of adult Listeria monocytogenes meningitis are not commonly examined in isolation in the literature. During a study period of 19 years (2000-2018), 366 patients with culture-proven adult bacterial meningitis (ABM) were identified in the author's hospital (264 patients in 2000-2010 and 102 patients in 2011-2018). Of the 366 ABM patients, 330 had monomicrobial infections while the other 36 had mixed infections. L. monocytogenes infection was identified in 11 of the 330 patients with monomicrobial ABM (3 in 2000-2010 and 8 in 2011-2018). These 11 patients included 5 males and 6 females, aged 47 to 76 years (median age = 61.7). None of the 11 patients had a postneurosurgical state as the underlying cause, but 3 of them contracted the infection nosocomially. Common underlying conditions included liver cirrhosis (4), systemic malignancy (3), diabetes mellitus (3), and renal disease (2). The most common clinical manifestations were fever (11), altered consciousness (8), seizure (8), bacteremia (7) and hydrocephalus (5). The therapeutic result revealed a mortality rate of 72.7% (8/11), but no significant prognostic factors were identified. The clinical features of 8 additional Taiwanese L. monocytogenes ABM patients reported in the literature, were also included for analysis. The present study revealed an increase in L. monocytogenes ABM in recent years and most patients presented with severe neurological manifestations. The current study is a preliminary overview of L. monocytogenes meningitis in adults and a further large-scale study is needed for improved delineation of this specific infectious syndrome.

The clinical course and outcome of Listeria monocytogenes meningitis: A retrospective single center study.

BACKGROUND: The aim of the study was to determine clinical manifestations and outcome of Listeria monocytogenes meningitis (LM) and to compare with other forms of bacterial meningitis (BM). MATERIAL AND METHODS: We analyzed records of all adult patients with BM who were hospitalized between January 2010 and December 2017 in the largest neuroinfection center in Poland. RESULTS: Out of 343 analyzed patients with BM 24 were diagnosed to have LM. Patients with LM were older compared to patients with other forms of BM (62 years vs. 57 years, p=0.039), were more likely to have cancer (16.7% vs. 4.7%, p=0.045), receive immunosuppressive treatment (45.8% vs. 10.7%, p<0.001), or be immunocompromised in any way (62.5% vs. 35.5%, p=0.016). Blood tests showed lower WBC (10.7 × 103 cells/µl vs. 15.5 × 103 cells/µl, p=0.004), C-reactive protein (150 mg/L vs. 221 mg/L, p=0,019) and procalcitonin (1.27 ng/mL vs. 3.78 ng/mL, p=0.003) in LM group. Analysis of cerebrospinal fluid showed lower cell count (531.5 cells/µL vs. 1100 cells/µL, p<0.001) and lower chloride (113 mmol/L vs. 117 mmol/L, p=0.036) in patients with LM. In the multiple logistic regression analysis, immunosuppressive therapy was the only variable independently associated with LM (OR:8.72, CI 95%:1.41-64.34, p=0.024). CONCLUSIONS: LM is associated with older age, cancer and immunosuppressive therapy. However, in multivariate analysis only immunosuppressive therapy turned out to be an independent risk factor for LM.

Source tracking on a dairy farm reveals a high occurrence of subclinical mastitis due to hypervirulent Listeria monocytogenes clonal complexes.

AIMS: An extensive source investigation was conducted on a dairy farm with neurolisteriosis and subclinical mastitis cases to identify infection source and potential transmission routes of Listeria monocytogenes. METHODS AND RESULTS: A total of 36 L. monocytogenes isolates were obtained from animal clinical cases (neurolisteriosis and udder infection) and the farm environment (silage, faeces, water). Isolates were typed using pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS). Their virulence potential was assessed using the gentamicin protection assay and WGS-based identification of virulence genes. PFGE and WGS revealed a high genetic diversity of L. monocytogenes. An epidemiological link was confirmed for isolates from (i) several subclinical mastitis cases, (ii) silage and subclinical mastitis cases and (iii) different water sources. The neurolisteriosis isolate belonged to clonal complex (CC) 1, but infection source was not identified. A high occurrence (9/47 cows; 19·1%) of subclinical mastitis was observed with isolates belonging to CC2, CC4 and CC11. CONCLUSIONS: The dairy farm environment was contaminated with diverse L. monocytogenes strains, including genotypes associated with human disease. Several isolates harboured genetic determinants associated with increased infectious potential in humans. SIGNIFICANCE AND IMPACT OF THE STUDY: Results suggest that subclinical listerial mastitis should not be neglected as a potential source of milk contamination. The presence of hypervirulent CCs in subclinical mastitis cases calls for the implementation of improved mastitis detection.

Listeria Meningitis in Danish Children 2000-2017: A Rare Event Even in a Country With High Rates of Invasive Listeriosis.

Listeria monocytogenes meningitis in Danish children 1 month to 17 years from 2000 to 2017 was identified and patient files reviewed. There were 5 cases, equaling an annual incidence of 0.024 per 100,000 children or 0.014 when excluding 2 immunodeficient children. Even in a country with a high general incidence of listeriosis, Listeria meningitis is a rare event in healthy children.

Epidemiology and treatment of the commonest form of listeriosis: meningitis and bacteraemia.

Listeria monocytogenes is a Gram-positive bacillus and facultative intracellular bacterium whose transmission occurs mainly through the consumption of contaminated food. Listeriosis has an incidence estimated at around three-six cases per million per year and the most common forms of the infection are neurolisteriosis, bacteraemia, and maternal-neonatal infection. Those affected by listeriosis are at the extremes age of the life or report specific risk factors, such as malignancies, causing a defect of cellular immunity. Patients with L. monocytogenes meningitis present with signs and symptoms similar to those reported in the general population with community-acquired bacterial meningitis, but can experience a longer prodromal phase. Instead, patients with bacteraemia present generally with a febrile illness without focal symptoms, or with influenza-like symptoms and diarrhoea. These aspecific findings make the diagnosis difficult in the population of patients at the highest risk such as cirrhotics or those receiving chemotherapy. Mortality rate is estimated around 20% with a significant increase among those reporting a delay in diagnosis and treatment and in those with severe comorbidity. A number of antibiotics have been demonstrated to be active against L. monocytogenes, but penicillin, amoxicillin, and ampicillin are those used with the highest frequency and suggested by current guidelines and expert opinions. These antibiotics bind to PBP-3 with high affinity and are stored in the cytosol when taken up by cells. Although amoxicillin appears to have a better activity than ampicillin on the basis of in vitro studies, ampicillin is currently the drug of choice for the treatment of listeriosis. Cotrimoxazole could be administered as an alternative treatment; its use is associated with a favourable outcome probably due to the favourable penetration with brain. Quinolones have an excellent tissue and cell penetration and are rapidly bactericidal, but their clinical activity is not as high as we can predict on the basis of experimental model. Linezolid offers a number of advantages in the empiric treatment of meningitis due to its favourable penetration of CSF and the absence of bacteriolytic effect on S. pneumoniae as confirmed by a number of case-series highlighting its use as rescue therapy of pneumococcal meningitis, but data are currently limited particularly if we consider neurolisteriosis. Combination therapies have been proposed to enhance the activity of penicillins against Listeria in an attempt to achieve complete killing and decrease mortality. Steroids use is ineffective.

Listeria monocytogenes meningitis in the Netherlands, 1985-2014: A nationwide surveillance study.

OBJECTIVES: Listeria monocytogenes can cause sepsis and meningitis. We report national surveillance data on L. monocytogenes meningitis in the Netherlands, describing incidence changes, genetic epidemiology and fatality rate. METHODS: We analyzed data from the Netherlands Reference Laboratory of Bacterial Meningitis for cases of L. monocytogenes meningitis. Strains were assessed by serotyping and bacterial population structure by multi-locus sequence typing. RESULTS: A total of 375 cases of Listeria meningitis were identified between 1985 and 2014. Peak incidence rates were observed in neonates (0.61 per 100,000 live births) and older adults (peak at 87 year; 0.53 cases per 100,000 population of the same age). Neonatal listerial meningitis decreased 17-fold from 1.95 per 100,000 live births between 1985 and 1989, to 0.11 per 100,000 live births between 2010 and 2014. Overall case fatality rate was 31%, in a multivariate analysis older age and concomitant bacteremia were associated with mortality (both p < 0.01). Clonal complexes (CC) CC1, CC2 and CC3 decreased over time from respectively 32% to 12%, 33% to 9% and 10% to 2% (all p < 0.001), while CC6 increased from 2% to 26% (p < 0.001). CONCLUSIONS: The incidence of neonatal listerial meningitis has declined over the past 25 years. The genotype CC6 has become the predominant genotype in listerial meningitis in the Netherlands. Mortality of listeria meningitis has remained high.

Predictive risk factors for Listeria monocytogenes meningitis compared to pneumococcal meningitis: a multicenter case-control study.

PURPOSE: Various immunocompromised conditions increase the risk of meningitis caused by Listeria monocytogenes. However, the relative importance of these risk factors has not been well established. We determined the risk factors that predict meningitis due to L. monocytogenes compared to that caused by Streptococcus pneumoniae. METHODS: A nationwide multicenter case-control study was conducted in Korea. Cases of meningitis caused by L. monocytogenes between 1998 and 2013 were included. Patients with pneumococcal meningitis were included as controls. Multivariate logistic regression analysis was used to predict the risk factors of Listeria meningitis. RESULTS: A total of 36 cases and 113 controls were enrolled. The most significant predictive risk factor of Listeria meningitis was a prior history of receiving immunosuppressive therapy (odds ratio 8.12, 95 % CI 2.47-26.69). Chronic liver disease was the second most important predictive risk factor (OR 5.03, 95 % CI 1.56-16.22). Delaying appropriate antibiotic therapy by more than 6 h (hazard ratio 2.78) and fatal underlying disease (hazard ratio 2.88) were associated with increased mortality. CONCLUSIONS: Patients with a prior history of receiving immunosuppressive therapy within 1 month and chronic liver disease have 8.1-fold and 5-fold increased risk of meningitis by L. monocytogenes compared to S. pneumoniae, respectively.

Listeria monocytogenes meningitis in the elderly: epidemiological, clinical and therapeutic findings.

Listeria monocytogenes is a Gram-positive bacillus and facultative intracellular bacterium whose transmission occurs mainly through the consumption of contaminated food, L. monocytogenes invades the host cells using various protein and can escape to the human T-cell immune system by cell-to-cell spreading. If the infection is not controlled at the stage in which the bacterium is in the liver, for instance, due to a severe immunodepression, a secondary bacteraemia can be developed and L. monocytogenes reaches the preferred sites transgressing the blood-brain barrier or the placental barrier. Individuals with T-cell dysfunction, such as pregnant women, the elderly, and those receiving immunosuppressive therapy are at the highest risk of contracting the disease. Average life expectancy throughout developed countries has rapidly increased during the latter half of the 20th century and geriatric infectious diseases have become an increasingly important issue. L. monocytogenes meningitis in young previously healthy adults has been reported only in anecdotal observations. Differently, L. monocytogenes is the third most common cause of bacterial meningitis in the elderly population, after Streptococcus pneumoniae and Neisseria meningitidis. Patients with L. monocytogenes meningitis presented with signs and symptoms that were similar to those of the general population with community-acquired bacterial meningitis, but reported a longer prodromal phase. According to literature data, the prevalence of the classic triad of fever, neck stiffness, and altered mental status is 43%, and almost all patients present with at least 2 of the 4 classic symptoms of headache, fever, neck stiffness, and altered mental status. On the basis of our published data, in patients aged over 50 years, diagnosing L. monocytogenes meningitis was more challenging than pneumococcal meningitis, as demonstrated by the lower percentage of cases receiving a correct diagnosis within 48 hours from the onset of symptoms. No significant difference was observed in respect to the presenting symptoms, but progression to respiratory failure was not as rapid as pneumococcal meningitis.

Community-acquired bacterial meningitis in adults with cancer or a history of cancer.

OBJECTIVES: To study the incidence, clinical presentation, causative bacteria, and outcome of community-acquired bacterial meningitis in adults with cancer. METHODS: We evaluated incidence and characteristics of patients with cancer included in a nationwide prospective cohort study of adults with community-acquired meningitis performed in the Netherlands from March 1, 2006, to September 31, 2014. All patients underwent a neurologic examination at hospital discharge, and outcome was graded using the Glasgow Outcome Scale. RESULTS: Active cancer was identified in 68 of 1,351 episodes (5%) and a history of cancer in 87 (6%). The annual incidence of community-acquired bacterial meningitis was 2.71-fold (95% confidence interval [CI] 1.68-4.36, p < 0.001) increased for patients with cancer compared to patients without cancer in 2010, and 3.52-fold (95% CI 2.16-5.73, p < 0.001) in 2013. The clinical presentation of bacterial meningitis in patients with cancer compared to patients without cancer was similar. Patients with active cancer presented with lower leukocyte count in blood (12.1 × 10(9) cells/L vs 17.3 × 10(9) cells/L, p < 0.001) and CSF (670 cells/mm(3) vs 2,567 cells/mm(3), p < 0.001) and were more likely to be infected with Listeria monocytogenes (21% vs 5%, p < 0.001) than patients without cancer. Active cancer was identified as an independent risk factor for unfavorable outcome in bacterial meningitis (odds ratio 1.85, 95% CI 1.09-3.13). CONCLUSIONS: One of 8 patients with community-bacterial meningitis was identified to have a history of cancer and cancer was considered active in half of these patients. Patients with active cancer present with lower CSF leukocyte counts, are more likely to be infected with L monocytogenes, and are at high risk of unfavorable outcome.

Neonatal bacterial meningitis: Results from a cross-sectional hospital based study.

OBJECTIVE: The aim of the study was to determine the epidemiological characteristics of bacterial meningitis observed in neonates born in the Department of Gynaecology and Obstetrics, University Clinical Centre Tuzla, Bosnia and Herzegovina, admitted to Intensive care unit (NICU) or readmitted, because of suspected infection, after discharge from the nursery. SUBJECTS AND METHODS: This study was carried out from July 1, 2012 to June 30, 2013. During this period 4136 neonates were born. All neonates admitted to the Intensive care unit with signs and symptoms of systemic infections, and neonates readmitted to the Intensive care unit, after discharge from the nursery for sepsis work up were included in the study. RESULTS: Eighteen of 200 neonates (9%) admitted or readmitted to the NICU developed meningitis. 61% cases were late onset meningitis. The overall incidence was 4.4/1000 live births. The mortality rate was 11.1%. The mean age of symptom presentation was 8.7 days. The most common clinical features were: fever, respiratory distress and jaundice. Significant risk factors for acquiring meningitis were: male gender, Caesarean delivery, stained amniotic fluid. Positive CSF finding were detected in 6/18 (33.3%) of cases. Gram-positive bacteria were more frequently responsible for confirmed meningitis. In all neonates with meningitis blood culture was examined and 5 (50%) yielded Gram-negative bacteria. CONCLUSION: The high rates of neonatal meningitis with predominant late onset may suggest nosocomial origin. Measures to improve antenatal, intrapartum and delivery care and measures during NICU hospitalisation are necessary to lower the risk of nosocomial infections.

Disease Burden of Invasive Listeriosis and Molecular Characterization of Clinical Isolates in Taiwan, 2000-2013.

The information about disease burden and epidemiology of invasive listeriosis in Asia is scarce. From 2000 to 2013, a total of 338 patients with invasive listeriosis (bacteremia, meningitis, and peritonitis) were treated at four medical centers in Taiwan. The incidence (per 10,000 admissions) of invasive listeriosis increased significantly during the 14-year period among the four centers (0.15 in 2000 and >1.25 during 2010-2012) and at each of the four medical centers. Among these patients, 45.9% were elderly (>65 years old) and 3.3% were less than one year of age. More than one-third (36.7%) of the patients acquired invasive listeriosis in the spring (April to June). Among the 132 preserved Listeria monocytogenes isolates analyzed, the most frequently isolated PCR serogroup-sequence type (ST) was IIb-ST87 (23.5%), followed by IIa-ST378 (19.7%) and IIa-ST155 (12.1%). Isolation of PCR serogroups IIb and IVb increased significantly with year, with a predominance of IIb-ST87 isolates (23.5%) and IIb-ST 228 isolates emerging in 2013. A total of 12 different randomly amplified polymorphic DNA (RAPD) patterns (Patterns I to XII) were identified among the 112 L. monocytogenes isolates belonging to eight main PCR serogroup-STs. Identical RAPD patterns were found among the isolates exhibiting the same PCR serogroup-ST. In conclusion, our study revealed that during 2000-2013, listeriosis at four medical centers in Taiwan was caused by heterogeneous strains and that the upsurge in incidence beginning in 2005 was caused by at least two predominant clones.

The clinical features, diagnosis, treatment, and prognosis of neuroinvasive listeriosis: a multinational study.

The aim of this study was to determine the independent risk factors, morbidity, and mortality of central nervous system (CNS) infections caused by Listeria monocytogenes. We retrospectively evaluated 100 episodes of neuroinvasive listeriosis in a multinational study in 21 tertiary care hospitals of Turkey, France, and Italy from 1990 to 2014. The mean age of the patients was 57 years (range, 19-92 years), and 64% were males. The all-cause immunosuppression rate was 54 % (54/100). Forty-nine (49 %) patients were referred to a hospital because of the classical triad of symptoms (fever, nuchal rigidity, and altered level of consciousness). Rhombencephalitis was detected radiologically in 9 (9 %) cases. Twenty-seven (64 %) of the patients who had cranial magnetic resonance imaging (MRI) performed had findings of meningeal and parenchymal involvement. The mean delay in the initiation of specific treatment was 6.8 ± 7 days. Empiric treatment was appropriate in 52 (52 %) patients. The mortality rate was 25 %, while neurologic sequelae occurred in 13 % of the patients. In the multivariate analysis, delay in treatment [odds ratio (OR), 1.07 [95 % confidence interval (CI), 1.01-1.16]] and seizures (OR, 3.41 [95 % CI, 1.05-11.09]) were significantly associated with mortality. Independent risk factors for neurologic sequelae were delay in treatment (OR, 1.07 [95 % CI, 1.006-1.367]) and presence of bacteremia (OR, 45.2 [95 % CI, 2.73-748.1]). Delay in the initiation of treatment of neuroinvasive listeriosis was a poor risk factor for unfavorable outcomes. Bacteremia was one of the independent risk factors for morbidity, while the presence of seizures predicted worse prognosis. Moreover, the addition of aminoglycosides to ampicillin monotherapy did not improve patients' prognosis.

Listeria monocytogenes sequence type 6 and increased rate of unfavorable outcome in meningitis: epidemiologic cohort study.

BACKGROUND: We analyzed clinical characteristics, treatment, genetic diversity, and outcome of 92 adults with Listeria monocytogenes meningitis included in 2 prospective nationwide cohort studies. METHODS: Episodes of community-acquired listerial meningitis confirmed by cerebrospinal fluid culture were included from 1998 to 2002 and 2006 to 2012. We compared patients and pathogen characteristics between cohorts and identified predictors for an unfavorable outcome according to the Glasgow Outcome Scale. RESULTS: Thirty episodes were included from 1998 to 2002 and 62 from 2006 to 2012; clinical and laboratory characteristics on admission were similar between cohorts. However, the rate of unfavorable outcome increased from 27% in the 1998-2002 cohort to 61% in the 2006-2012 cohort (P = .002). Differences between cohorts were increased use of adjunctive dexamethasone therapy (0% in 1998-2002 vs 53% in 2006-2012; P < .001) and emergence of infection by L. monocytogenes genotype sequence type 6 (ST6; 4% in 1998-2002 vs 29% in 2006-2012; P = .009). Multivariate regression analysis identified infection with L. monocytogenes ST6 as the sole predictor of unfavorable outcome (odds ratio, 3.77; 95% confidence interval, 1.07-13.33). Patients infected with genotypes other than ST6 also had an increased rate of unfavorable outcome over time (P = .03). CONCLUSIONS: The rate of unfavorable outcome among adults with listerial meningitis has increased over a 14-year period, from 27% to 61%. The emerging L. monocytogenes genotype ST6 was identified as the main factor leading to poorer prognosis. Adjunctive dexamethasone may be discontinued if L. monocytogenes is identified, as there is no proven benefit in Listeria meningitis.

[Meningitis due to Listeria monocytogenes in adults]. / Meningitis por Listeria monocytogenes en adultos.

INTRODUCTION: Listeria monocytogenes is the third most common cause of community-acquired bacterial meningitis in adults. AIMS: To describe the characteristics of meningitis caused by Listeria (LM) in adults and to compare them with those of meningitis due to other causations (nLM). PATIENTS AND METHODS: A retrospective analysis of a series of hospital cases was conducted, including patients aged between ≥ 14 years diagnosed with LM in a referral hospital between 1982 and 2011. RESULTS: The study involves 16 cases of LM, 12.1% of the cases of community-acquired meningitis with an identified aetiology. Predisposing factors were age (mean of 65 versus 52 years; p = 0.019) and immunosuppression/comorbidity (62.5% versus 3.4%; p < 0.001), treatment with corticoids (37.5%) and chronic liver disease (25%) being the most frequent. The classical triads of acute bacterial meningitis, clinical features and analysis of the cerebrospinal fluid (CSF) were observed in 50 and 75% of the cases, respectively. Patients with LM presented lower leukocyte counts in CSF, a lower percentage of neutrophils, a greater frequency of lymphocytic pleocytosis and a lower frequency of Gram stain positive than those with nLM. The mortality rate was 12.5%, similar to that of patients with nLM. CONCLUSIONS: LM mainly affects patients who are immunosuppressed or with comorbidity, as well as elderly patients, although it may occur in the absence of risk factors. Clinically it does not differ from other causes of meningitis, but the initial CSF study may suggest it. Its mortality rate is similar to that of meningitis due to other aetiologies.

[Nosocomial outbreak due to Listeria monocytogenes in a neonatal unit]. / Brote nosocomial por Listeria monocytogenes en una Unidad de Neonatos.

INTRODUCTION: Description of an outbreak of Listeria monocytogenes in a neonatal intensive care unit. METHODS: A questionnaire, environmental investigation and molecular study were performed. RESULTS: We identified a nosocomial outbreak of L. monocytogenes, confirmed by the genetic study, in a neonatal intensive care unit. Three infants were affected. Although the transmission mechanism could not be elucidated, cross-infection was strongly suggested. CONCLUSION: Adherence to universal hygiene standards is necessary to avoid nosocomial outbreaks.

Long-term mortality in patients diagnosed with Listeria monocytogenes meningitis: a Danish nationwide cohort study.

OBJECTIVES: To determine the long-term mortality, the causes of death and the incidence of cancer in listeria meningitis patients. METHODS: Nationwide, population-based cohort study including all adult patients diagnosed with listeria meningitis from 1977 to 2006 and alive 1 year after diagnosis, and an age-and gender-matched, population control cohort. Kaplan-Meier tables, Cox regression analysis and cumulative incidence function were used as outcome analyses. RESULTS: We identified 114 listeria meningitis patients and 1026 population controls. The adjusted mortality rate ratio (MRR) for listeria meningitis patients the first 5 years of follow-up was 2.35(95% confidence interval (CI) 1.60-3.45) thereafter the MRR was 0.93(95% CI: 0.56-1.55). Listeria meningitis patients had an increased risk of death due to cancer the first 5 years of follow-up, and in the same period patients above 50 years of age had a 2-fold increased risk of being diagnosed with cancer, thereafter the risks declined to that of the background population. CONCLUSIONS: The long-term mortality in adult patients diagnosed with listeria meningitis was increased the first 5 years of follow-up, mainly due to death from cancer, thereafter the mortality did not differ from the background population. To improve survival this patient population should be meticulously screened for predisposing conditions, mainly underlying malignant diseases.