Severe meningitis due to Listeria monocytogenes. A review of 40 cases in adults

Listeria monocytogenes encephalitis in France

PURPOSE

The authors had for aim to describe the characteristics of listeriosis encephalitis patients enrolled in a national study.

METHODS

Listeria monocytogenes was identified as the forth etiology of encephalitis, in a prospective study in France, in 2007. We analyzed 12 cases with confirmed listeriosis (seven with rhombencephalitis, five with encephalitis) and compared them with encephalitis of other etiologies and with listeriosis encephalitis, mandatorily notified during the same year.

RESULTS

L. monocytogenes strains were genoserotyped as IVb (n=6), IIa (n=3), and IIb (n=3). Cerebrospinal fluid (CSF) median protein level was 2.5g/L and the median WBC counts was 367cells/mm(3). Among twelve patients, seven patients had ongoing comorbidities. The case fatality rate during hospitalization was 50%. Patients presenting with listeriosis enrolled in the study did not differ from those reported to the mandatory surveillance system according to their demographical characteristics and comorbidities. They were older, presented more frequently with cancer, or were more often under corticosteroid treatment than patients presenting with encephalitis due to other etiologies.

CONCLUSIONS

Neurolisteriosis has a poor prognosis, thus it should be considered early in patients presenting with encephalitis to improve its management.

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.

Three-year multicenter surveillance of community-acquired Listeria monocytogenes meningitis in adults

Background

Listeria monocytogenes is the third most frequent cause of bacterial meningitis. The aim of this study is to know the incidence and risk factors associated with development of acute community-acquired Lm meningitis in adult patients and to evaluate the clinical features, management, and outcome in this prospective case series.

Methods

A descriptive, prospective, and multicentric study carried out in 9 hospitals in the Spanish Network for Research in Infectious Diseases (REIPI) over a 39-month period. All adults patients admitted to the participating hospitals with the diagnosis of acute community-acquired bacterial meningitis (Ac-ABM) were included in this study. All these cases were diagnosed on the basis of a compatible clinical picture and a positive cerebrospinal fluid (CSF) culture or blood culture. The patients were followed up until death or discharge from hospital.

Results

Two hundred and seventy-eight patients with Ac-ABM were included. Forty-six episodes of Lm meningitis were identified in 46 adult patients. In the multivariate analysis only age (OR 1.026; 95% CI 1.00-1.05; p = 0.042), immunosupression (OR 2.520; 95% CI 1.05-6.00; p = 0.037), and CSF/blood glucose ratio (OR 39.42; 95% CI 4.01-387.50; p = 0.002) were independently associated with a Lm meningitis. The classic triad of fever, neck stiffness and altered mental status was present in 21 (49%) patients, 32% had focal neurological findings at presentation, 12% presented cerebellum dysfunction, and 9% had seizures. Twenty-nine (68%) patients were immunocompromised. Empirical antimicrobial therapy was intravenous ampicillin for 34 (79%) of 43 patients, in 11 (32%) of them associated to aminoglycosides. Definitive ampicillin plus gentamicin therapy was significantly associated with unfavourable outcome (67% vs 28%; p = 0.024) and a higher mortality (67% vs 32%; p = 0.040).The mortality rate was 28% (12 of 43 patients) and 5 of 31 (16.1%) surviving patients developed adverse clinical outcome.

Conclusions

Elderly or immunocompromised patients, and a higher CSF/blood glucose ratio in patients with Ac-ABM must alert clinicians about Lm aetiology. Furthermore, we observed a high incidence of acute community-acquired Lm meningitis in adults and the addition of aminoglycosides to treatment should be avoid in order to improve the patients' outcome. Nevertheless, despite developments in intensive care and antimicrobial therapy, this entity is still a serious disease that carries high morbidity and mortality rates.

Listeria monocytogenes encephalitis mimicking West Nile encephalitis

We present a case of a 50-year-old man who presented to Winthrop-University Hospital in the midst of the 2002 West Nile encephalitis (WNE) outbreak with the cardinal clinical findings of WNE, ie, fever, encephalopathy, weakness, and muscle tremors. During the summer of 2002, several cases of aseptic meningitis/viral encephalitis were admitted to our emergency room weekly. In addition, cases of WNE were being admitted at the same time. During this period we had 3 cases of WNE. Our patient presented with the clinical findings of WNE. However, laboratory and radiologic findings suggested the possibility of Listeria monocytogenes encephalitis. The cerebrospinal fluid findings included red blood cells, which, in the absence of a traumatic tap or HSV encephalitis, argue against the diagnosis of WNE but are consistent with L. monocytogenes encephalitis. Computed tomography scan showed communicating hydrocephalus, which also suggests the possibility of L. monocytogenes and argued against the diagnosis of WNE. Clinicians should be vigilant for the mimics of WNE in geographical areas where WNE outbreaks are occurring.

Invasion of the central nervous system by intracellular bacteria

Infection of the central nervous system (CNS) is a severe and frequently fatal event during the course of many diseases caused by microbes with predominantly intracellular life cycles. Examples of these include the facultative intracellular bacteria Listeria monocytogenes, Mycobacterium tuberculosis, and Brucella and Salmonella spp. and obligate intracellular microbes of the Rickettsiaceae family and Tropheryma whipplei. Unfortunately, the mechanisms used by intracellular bacterial pathogens to enter the CNS are less well known than those used by bacterial pathogens with an extracellular life cycle. The goal of this review is to elaborate on the means by which intracellular bacterial pathogens establish infection within the CNS. This review encompasses the clinical and pathological findings that pertain to the CNS infection in humans and includes experimental data from animal models that illuminate how these microbes enter the CNS. Recent experimental data showing that L. monocytogenes can invade the CNS by more than one mechanism make it a useful model for discussing the various routes for neuroinvasion used by intracellular bacterial pathogens.

Bacterial meningitis

In recent years, investigators have made significant advances in understanding the pathogenesis of bacterial meningitis, particularly with regard to understanding the cascade of biologic events that cause excessive inflammation within the central nervous system (CNS). Nevertheless, the most important event in the field of bacterial meningitis in the past decade is the dramatic decline in the incidence of Haemophilus influenzae meningitis in children as a result of the widespread use of the conjugated H. influenzae type b vaccine. Currently, the most important clinical challenge in this field is the emergence of the drug-resistant Streptococcus pneumoniae. This problem has significantly complicated initial management of patients with suspected bacterial meningitis. Preliminary data show promise with new conjugated S. pneumoniae vaccines.

Central nervous system infection with Listeria monocytogenes. 33 years' experience at a general hospital and review of 776 episodes from the literature

We reviewed 776 previously reported and 44 new cases of CNS listeriosis outside of pregnancy and the neonatal period, and evaluated the epidemiologic, diagnostic, and therapeutic characteristics of this infection. Among patients with Listeria meningitis/meningoencephalitis, hematologic malignancy and kidney transplantation were the leading predisposing factors, but 36% of patients had no underlying diseases recognized. The infection occurred throughout life, with a higher incidence before the age of 3 and after the age of 45-50 years. Fever, altered sensorium, and headache were the most common symptoms, but 42% of patients had no meningeal signs on admission. Compared with patients with acute meningitis due to other bacterial pathogens, patients with Listeria infection had a significantly lower incidence of meningeal signs, and the CSF profile was significantly less likely to have a high WBC count or a high protein concentration. Gram stain of CSF was negative in two-thirds of cases of CNS listeriosis. One-third of patients had focal neurologic findings, and approximately one-fourth developed seizures over their course. Mortality was 26% overall, and was higher among patients with seizures and those older than 65 years of age. Relapse occurred in 7% of episodes. Ampicillin for a minimum of 15-21 days (with an aminoglycoside for at least the first 7-10 days) remains the treatment of choice. Cerebritis/abscess due to L. monocytogenes, without meningeal involvement, is less common but may be diagnosed by blood cultures and CNS imaging, or by stereotactic biopsy. Longer antibiotic therapy (at least 5-6 weeks) is needed in the presence of localized CNS involvement.

Listeriosis in 225 non-pregnant patients in 1992: clinical aspects and outcome in relation to predisposing conditions

Clinical information was collected on 225 cases of Listeria monocytogenes (LM) infection not associated with pregnancy occurring in France in 1992. Infections affected primarily men (62%) and persons over 65 years of age. Of the cases found, 81% occurred in persons with some underlying condition: 34% involved patients with severe immunosuppression; 37% were on dialysis or had diabetes mellitus, alcoholism, hepatic failure or malignancies without immunosuppressive therapy; and 10% had other underlying conditions not clearly associated with immunosuppression. The clinical presentation of listeriosis depended on the predisposing factors: in previously healthy adults central nervous system infection was the most frequent clinical form (80%), whereas the group characterized by severe immunosuppression or other immunosuppressive conditions tended to develop bacteraemia (52%). The rate of hospital-associated cases (11%) was lower than that reported in other countries. Mortality directly related to LM infection was 24%. Predisposing disease was the major prognostic factor. No fatal outcome was observed in the group of adults < 65 years old without underlying conditions. In summary, although classification based on the degree of alteration of T-cell-mediated immunity enables determination of the role of predisposing conditions in cases of listeriosis outside of pregnancy, clinical aspects and outcome of listeriosis vary within these groups and depend on the severity of each underlying disease.

Antimicrobial chemotherapy of human infection due to Listeria monocytogenes

Listeriosis is an uncommon infection, but when it occurs it carries a high mortality rate. Early diagnosis is essential and thereafter appropriate antimicrobial chemotherapy. Ampicillin or penicillin plus gentamicin remains the treatment of choice for most manifestations of listeriosis, and adequate doses must be given, i.e. greater than 6g/day of ampicillin or penicillin. Co-trimoxazole appears to be an excellent alternative agent with good penetration into the cerebrospinal fluid. Vancomycin is an appropriate agent for the treatment of primary bacteraemia but does not cross the blood-brain barrier sufficiently well to be useful in meningitis, while erythromycin may be used to treat listeriosis in cases of pregnancy. Treatment of bacteraemia requires one to two weeks' therapy, while meningitis cases may need to be treated for longer; for example, it has been found that most patients with acute meningitis in the UK were treated for 20 days. Infective endocarditis needs treatment for six to eight weeks. Doses should be varied with patients' altered organ function and antimicrobial serum monitoring performed when appropriate.

Spectrum and outcome of microbiologically documented listeria monocytogenes infections in cancer patients

At the M.D. Anderson Cancer Center (Houston), Listeria monocytogenes was cultured from 14 patients between 1980 and 1987. The case records of 11 of these patients were reviewed. Underlying malignancies included acute leukemia (three), lymphoma (two), myeloma (one), adenocarcinoma of colon (two), carcinoma of breast (one), carcinoma of lung (one), and Kaposi's sarcoma associated with the acquired immune deficiency syndrome (one). Listeria monocytogenes was cultured from blood (eight patients), cerebrospinal fluid (CSF) (two patients), and from both blood and CSF in one patient. All patients were receiving immunosuppressive therapy including corticosteroids in seven. An absolute neutrophil count of less than 1000/mm3 was noted in five. Bacteremia was the predominant type of infection and ten patients responded to antimicrobial therapy.

Listeria monocytogenes meningitis in adults. Sixteen consecutive cases 1973-1982

16 adult patients with Listeria monocytogenes meningitis were reviewed to see whether clinical features or initial laboratory findings could discriminate between these patients and patients with purulent meningitis of other causes. Six patients suffered from known predisposing diseases and 4 were alcoholics. The initial clinical picture was indistinguishable from meningitis of other causes. Microscopy of cerebrospinal fluid (CSF) was negative in all cases but 2 where gram-positive rods were seen. CSF cytology and biochemistry could not discriminate from other causes of purulent meningitis although a low leucocyte content and a low percentage of neutrophils were often present. All L. monocytogenes strains isolated were sensitive to ampicillin and aminoglycosides whereas susceptibility to other antibiotics was low or varying. In adult patients suffering from purulent meningitis initial therapy should include ampicillin until an etiological diagnosis is established. The same is true in some cases of febrile encephalopathy with low content of neutrophils in CSF, especially when the glucose content is low.

Non-neonatal meningitis due to less common bacterial pathogens, the Netherlands, 1975-83

In the Netherlands, case histories of 160 patients aged more than 1 month, with meningitis due to bacteria other than Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae were reviewed in order to look for associations between the bacteriological data and the course of disease. The incidence of such cases was about 0.8/100,000/year. Escherichia coli and Listeria monocytogenes each accounted for about 15% of the cases. The case-fatality rate was 18.8% (Gram-negative bacteria, 25%; Gram-positives, 15%) and sequelae occurred in 13.3% of the surviving patients (14 and 13% Gram-negative and Gram-positive, respectively). Hearing loss was the most prevalent sequela (5.0%). Predisposing factors were present in 70% of patients (69 and 71% respectively), especially in meningitis due to enteric Gram-negative bacteria (except for salmonella) and due to staphylococci. Surveillance is important because the incidence of meningitis due to these micro-organisms is likely to increase and because the problems in antibiotic treatment have not yet been solved.