Prolonged persistence of Listeria monocytogenes after intragastric infection in corticosteroid-treated mice

Listeria brain abscess in a patient with autoimmune hepatitis

Listeria monocytogenes is an uncommon cause of brain abscesses. Immunocompromised hosts, pregnant women and patients at extremes of age are especially susceptible. We discuss the successful management of a woman with autoimmune hepatitis on prednisone and azathioprine therapy with a L. monocytogenes brain abscess. Previously thought to be a rare cause of central nervous system (CNS) infection, the incidence of CNS listeriosis has increased due to a rise in organ and bone marrow transplantation requiring immunosuppressive medications. L. monocytogenes brain abscesses are now more frequently described and are associated with high rates of concomitant bacteremia suggesting a hematogenous route of infection.

Mortality from Listeria monocytogenes meningoencephalitis following escalation to alemtuzumab therapy for relapsing-remitting Multiple Sclerosis

We report the case of a patient who died from the rare complication of Listeriosis in the immediate phase following alemtuzumab administration one month after discontinuing dimethyl fumarate (DMF). There is considerable overlap with typical post-infusion symptoms therefore high surveillance and low threshold for empirical or possible prophylactic antibiotic therapy is advocated.

Listeria monocytogenes infection associated with alemtuzumab - - a case for better preventive strategies

Background

The mortality of septicaemia, meningitis and encephalitis caused by Listeria monocytogenes is 20–40%. Twenty-one cases of invasive listeriosis associated with alemtuzumab, including at least 16 in patients with multiple sclerosis, have been published or reported to the World Health Organization Case Safety Reports Database. Three cases were fatal, including at least one patient treated for multiple sclerosis in 2016.

Case presentation

We report a patient with multiple sclerosis who developed pyrexia, nausea and abdominal discomfort few hours after the third and last infusion of her second alemtuzumab cycle. An infusion related reaction was suspected. The patient had however eaten soft cheese and raw sausage 3 days prior to treatment, and L. monocytogenes septicaemia was diagnosed based on positive blood cultures.

Conclusion

Listeriosis associated with alemtuzumab is a potentially fatal condition that can mimic an infusion related reaction. As in most other previously reported cases symptoms started rapidly after the last infusion, suggesting that the patient already carried the bacteria prior to the alemtuzumab infusions. The summary of product characteristics recommends patients to avoid foods associated with listeria at least 1 month after treatment. This recommendation should include also the last weeks prior to treatment.

Listeria Meningitis Complicating Alemtuzumab Treatment in Multiple Sclerosis--Report of Two Cases

Alemtuzumab, a humanized monoclonal antibody targeting the surface molecule CD52, leads to a rapid depletion of immune cells in the innate and adaptive immune system. In phase 2 and 3 trials in multiple sclerosis (MS), infections have been reported more frequently in alemtuzumab than in interferon beta treated patients. Here we report two patients treated with alemtuzumab for MS developing Listeria meningitis few days after the first infusion cycle. Both patients recovered completely after prompt diagnosis and adequate treatment. Physicians and patients should be aware of this serious, but treatable complication.

Dexamethasone effects on group B streptococcal infection in newborn rats

BACKGROUND

We previously published that human neutrophil-mediated bacterial killing of group B Streptococcus (GBS) in vitro was dependent on the timing and concentration of dexamethasone exposure.

HYPOTHESIS

Dexamethasone treatment would affect neutrophil mediated killing of GBS in an animal model.

METHODS

Wistar rat pups were randomly allocated to receive placebo or dexamethasone before, early or late after GBS infection. Suckling rats were infected with 104 or 105 colony-forming units of GBS or nothing. Pups were followed for survival, quantitative bacteremia, growth and neutrophil-mediated bacterial killing. Neutrophils for bacterial killing were obtained via cardiac puncture before infection. Statistics included chi square for survival, Mann-Whitney U test for bacteremia, analysis of variance for growth and paired Student's t test for bacterial killing analyses.

RESULTS

Dexamethasone treatment before invasive GBS infection decreases quantitative bacteremia, improves survival and improves neonatal neutrophil-mediated bacterial killing in suckling rats, whereas dexamethasone treatment after infection increases bacteremia and decreases survival. Regardless of timing of dexamethasone treatment, before or after invasive GBS infection, growth was significantly impaired in all suckling rats receiving dexamethasone compared with controls.

CONCLUSION

Treatment with dexamethasone before invasive GBS infection improves survival and decreases bacteremia in suckling rats; this appears in part to be mediated by improved neonatal neutrophil-mediated bacterial killing. We speculate that this improvement in outcome may be a result of improved number or function of neutrophil cell surface receptors.

Listeriosis in patients at a comprehensive cancer center, 1955-1997

Listeria monocytogenes infection occurred in 94 patients during 1955-1997 at Memorial Sloan-Kettering Cancer Center. The incidence was 0.5 (1955-1966), 0.96 (1970-1979), and 0.14 (1985-1997) cases per 1000 new admissions. Eighty-five patients (90%) were bacteremic, and 34 (36%) had evidence of intracranial infection. In 91 patients with cancer, 70 (77%) received chemotherapy for advanced or relapsed malignancy (n=51; 56%); 64 (68%) received corticosteroids. Breast cancer was the most common solid-organ cancer (n=14; 45%), and 34 (36%) had preexisting advanced liver disease. In 14 (39%) of 37 patients who died of listeriosis, death occurred within 48 h of L. monocytogenes isolation. Four (80%) of 5 patients with extracranial foci of infection died of their infection, compared with 33 (37%) of 89 patients with isolated bacteremia and/or intracranial infection (odds ratio, 2.34; P=.05). Most infections (60%) were due to L. monocytogenes serotype 1/2, and the remainder (40%) were due to serovar 4b. Listeriosis in these patients with cancer occurred most often in individuals receiving antineoplastic therapy for advanced or relapsed malignancy and systemic corticosteroids. The presence of advanced liver disease may have increased the risk of systemic listeriosis in susceptible patients with underlying cancer.

Listeria monocytogenes virulence and pathogenicity, a food safety perspective

Several virulence factors of Listeria monocytogenes have been identified and extensively characterized at the molecular and cell biologic levels, including the hemolysin (listeriolysin O), two distinct phospholipases, a protein (ActA), several internalins, and others. Their study has yielded an impressive amount of information on the mechanisms employed by this facultative intracellular pathogen to interact with mammalian host cells, escape the host cell's killing mechanisms, and spread from one infected cell to others. In addition, several molecular subtyping tools have been developed to facilitate the detection of different strain types and lineages of the pathogen, including those implicated in common-source outbreaks of the disease. Despite these spectacular gains in knowledge, the virulence of L. monocytogenes as a foodborne pathogen remains poorly understood. The available pathogenesis and subtyping data generally fail to provide adequate insight about the virulence of field isolates and the likelihood that a given strain will cause illness. Possible mechanisms for the apparent prevalence of three serotypes (1/2a, 1/2b, and 4b) in human foodborne illness remain unidentified. The propensity of certain strain lineages (epidemic clones) to be implicated in common-source outbreaks and the prevalence of serotype 4b among epidemic-associated stains also remain poorly understood. This review first discusses current progress in understanding the general features of virulence and pathogenesis of L. monocytogenes. Emphasis is then placed on areas of special relevance to the organism's involvement in human foodborne illness, including (i) the relative prevalence of different serotypes and serotype-specific features and genetic markers; (ii) the ability of the organism to respond to environmental stresses of relevance to the food industry (cold, salt, iron depletion, and acid); (iii) the specific features of the major known epidemic-associated lineages; and (iv) the possible reservoirs of the organism in animals and the environment and the pronounced impact of environmental contamination in the food processing facilities. Finally, a discussion is provided on the perceived areas of special need for future research of relevance to food safety, including (i) theoretical modeling studies of niche complexity and contamination in the food processing facilities; (ii) strain databases for comprehensive molecular typing; and (iii) contributions from genomic and proteomic tools, including DNA microarrays for genotyping and expression signatures. Virulence-related genomic and proteomic signatures are expected to emerge from analysis of the genomes at the global level, with the support of adequate epidemiologic data and access to relevant strains.

Gastrointestinal infections in the immunocompromised host

Gastrointestinal disease is a significant cause of morbidity and mortality in the immunocompromised patient. This article focuses on the infectious gastrointestinal complications associated with the treatment of malignant disease and with solid organ transplantation but not HIV. Gastrointestinal defenses and the various mechanisms by which they are impaired are reviewed. The major pathogens and malignancies of this patient population and an approach to their diagnosis, treatment, and prevention are discussed.