Effects of Fusobacterium necrophorum on the mesenteric microcirculation of guinea pigs

Retropharyngeal abscess due to Fusobacterium necrophorum complicated by progressive internal carotid artery stenosis and multiple cranial nerve palsies

BACKGROUND

A case of retropharyngeal abscess complicated by both artery and nerve injury has rarely been reported.

METHODS

A 36-year-old woman suddenly presented with right eye visual loss, dilated pupil, reduced direct light reflex, ptosis and ocular motility disorder on the side of inflammation progression, and was diagnosed with retropharyngeal abscess due to Fusobacterium necrophorum. The patient was treated only with antibiotics and, no further surgery was necessary but tracheotomy. Four months later, MRA showed right ICA occlusion and left ICA stenosis. MRI revealed continuous spread of inflammation due to the abscess from the retropharyngeal to the intracranial space.

RESULTS

These severe complications would be attributed to an endothelial damage to the arterial wall and an ischemic neuropathy caused by inflammation and thrombogenesis due to Fusobacterium necrophorum.

CONCLUSIONS

This case should provide a better understanding of the mechanism of vascular and cranial nerve injury due to retropharyngeal infections, and highlights the need for early antibiotic therapy and repeated vascular evaluation.

Proteomic Characterization of Plasma in Lemierre's Syndrome

BACKGROUND

 The underlying mechanisms of thrombosis in Lemierre's syndrome and other septic thrombophlebitis are incompletely understood. Therefore, in this case control study we aimed to generate hypotheses on its pathogenesis by studying the plasma proteome in patients with these conditions.

METHODS

 All patients with Lemierre's syndrome in the Skåne Region, Sweden, were enrolled prospectively during 2017 to 2021 as cases. Age-matched patients with other severe infections were enrolled as controls. Patient plasma samples were analyzed using label-free data-independent acquisition liquid chromatography tandem mass spectrometry. Differentially expressed proteins in Lemierre's syndrome versus other severe infections were highlighted. Functions of differentially expressed proteins were defined based on a literature search focused on previous associations with thrombosis.

RESULTS

 Eight patients with Lemierre's syndrome and 15 with other severe infections were compared. Here, 20/449 identified proteins were differentially expressed between the groups. Of these, 14/20 had functions previously associated with thrombosis. Twelve of 14 had a suggested prothrombotic effect in Lemierre's syndrome, whereas 2/14 had a suggested antithrombotic effect.

CONCLUSION

 Proteins involved in several thrombogenic pathways were differentially expressed in Lemierre's syndrome compared to other severe infections. Among identified proteins, several were associated with endothelial damage, platelet activation, and degranulation, and warrant further targeted studies.

Patients with Lemierre syndrome have a high risk of new thromboembolic complications, clinical sequelae and death: an analysis of 712 cases

BACKGROUND

Lemierre syndrome is characterized by head/neck vein thrombosis and septic embolism usually complicating an acute oropharyngeal bacterial infection in adolescents and young adults. We described the course of Lemierre syndrome in the contemporary era.

METHODS

In our individual-level analysis of 712 patients (2000-2017), we included cases described as Lemierre syndrome if these criteria were met: (i) primary site of bacterial infection in the head/neck; (ii) objectively confirmed local thrombotic complications or septic embolism. The study outcomes were new or recurrent venous thromboembolism or peripheral septic lesions, major bleeding, all-cause death and clinical sequelae.

RESULTS

The median age was 21 (Q1-Q3: 17-33) years, and 295 (41%) were female. At diagnosis, acute thrombosis of head/neck veins was detected in 597 (84%) patients, septic embolism in 582 (82%) and both in 468 (80%). After diagnosis and during in-hospital follow-up, new venous thromboembolism occurred in 34 (5.2%, 95% CI 3.8-7.2%) patients, new peripheral septic lesions became evident in 76 (11.7%; 9.4-14.3%). The rate of either was lower in patients who received anticoagulation (OR: 0.59; 0.36-0.94), higher in those with initial intracranial involvement (OR: 2.35; 1.45-3.80). Major bleeding occurred in 19 patients (2.9%; 1.9-4.5%), and 26 died (4.0%; 2.7-5.8%). Clinical sequelae were reported in 65 (10.4%, 8.2-13.0%) individuals, often consisting of cranial nerve palsy (n = 24) and orthopaedic limitations (n = 19).

CONCLUSIONS

Patients with Lemierre syndrome were characterized by a substantial risk of new thromboembolic complications and death. This risk was higher in the presence of initial intracranial involvement. One-tenth of survivors suffered major clinical sequelae.

Lemierre's syndrome due to Fusobacterium necrophorum

We present a case of a patient with Lemierre's syndrome caused by Fusobacterium necrophorum who developed a right frontal lobe brain abscess. We summarise the epidemiology, microbiology, pathogenesis, clinical presentation, diagnosis, complications, therapy, and outcomes of Lemierre's syndrome. F necrophorum is most commonly associated with Lemierre's syndrome: a septic thrombophlebitis of the internal jugular vein. Patients usually present with an exudative tonsillitis, sore throat, dysphagia, and unilateral neck pain. Diagnosis of septic thrombophlebitis is best confirmed by obtaining a CT scan of the neck with contrast. Complications of the disease include bacteraemia with septic abscesses to the lungs, joints, liver, peritoneum, kidneys, and brain. Treatment should include a prolonged course of intravenous beta-lactam antibiotic plus metronidazole.

[Recent portal and mesenteric venous thrombosis associated with Fusobacterium bacteremia]

SUMMARY

Septic pylephlebitis is usually a complication of intraabdominal infection in the region drained by the portal venous system. We report two cases of portal and mesenteric venous thrombosis associated with Fusobacterium necrophorum bacteremia, which did not show any obvious intra-abdominal source of infection with noninvasive imaging procedures. In one case, early anticoagulation treatment was associated with repermeation of the portal vein and its right branch. As in Bacteroides bacteremia, portal and/or mesenteric venous thrombosis should be searched for in case of Fusobacterium bacteremia of unknown origin. Repermeation of the portal vein and relief of extrahepatic portal hypertension can be achieved in these cases with early anticoagulation.

Human infection with Fusobacterium necrophorum (Necrobacillosis), with a focus on Lemierre's syndrome

Human infection with Fusobacterium necrophorum usually involves F. necrophorum subsp. funduliforme rather than F. necrophorum subsp. necrophorum, which is a common pathogen in animals. Lemierre's syndrome, or postanginal sepsis, is the most common life-threatening manifestation. Tonsillitis is followed by septic thrombophlebitis of the internal jugular vein and then a septicemia with septic emboli in lungs and other sites. Recent evidence suggests that F. necrophorum can be limited to the throat and cause persistent or recurrent tonsillitis. F. necrophorum is unique among non-spore-forming anaerobes, first for its virulence and association with Lemierre's syndrome as a monomicrobial infection and second because it seems probable that it is an exogenously acquired infection. The source of infection is unclear; suggestions include acquisition from animals or human-to-human transmission. Approximately 10% of published cases are associated with infectious mononucleosis, which may facilitate invasion. Recent work suggests that underlying thrombophilia may predispose to internal jugular vein thrombophlebitis. Lemierre's syndrome was relatively common in the preantibiotic era but seemed to virtually disappear with widespread use of antibiotics for upper respiratory tract infection. In the last 15 years there has been a rise in incidence, possibly related to restriction in antibiotic use for sore throat.

Fusobacterium necrophorum infection associated with portal vein thrombosis

This report describes a patient without obvious upper respiratory tract or gastrointestinal infection who developed portal vein thrombosis secondary to Fusobacterium necrophorum septicaemia. The patient responded well to systemic antibiotic therapy. The implications of F. necrophorum infection caudal to the head are discussed.

Increased diagnosis of Lemierre syndrome and other Fusobacterium necrophorum infections at a Children's Hospital

OBJECTIVE

To assess the apparent increase in the diagnosis of Lemierre syndrome (LS) and other Fusobacterium necrophorum infections at a large children's hospital. Infections with F necrophorum ranged from peritonsillar abscess to potentially fatal LS. LS is an oropharyngeal infection characterized by septic thrombophlebitis of head and neck veins, complicated by dissemination of septic emboli to pulmonary and systemic sites.

METHODS

Review of the medical and laboratory records was conducted of all patients who were seen at or admitted to the Children's Hospital of Wisconsin with the diagnosis of LS and/or isolation of F necrophorum from a clinical specimen between January 1995 and January 2002.

RESULTS

During the 7-year period of the study, there was an increase in the isolation of F necrophorum from patients who were seen at Children's Hospital of Wisconsin, as well as the number of cases of LS. There was 1 isolation of F necrophorum from clinical specimens per year from 1996 to 1999, which increased to 10 isolates of the organism from January 2000 to January 2002. During the most recent period, January 2001-January 2002, 5 cases of LS were diagnosed, a distinctive entity not recognized previously at the institution.

CONCLUSIONS

The cause for the recent increase in the number of serious infections caused by F necrophorum infection diagnosed at our institution is unclear but does not seem to be related to changes in microbiologic techniques or patient demography. We speculate that it could be attributable, in part, to alterations in antibiotic usage patterns in our region. Clinicians need to be aware of the increasing clinical importance of F necrophorum infections and the life-threatening nature of LS.

Human necrobacillosis, with emphasis on Lemierre's syndrome

Lemierre's syndrome is the classical presentation of human necrobacillosis. It is characterized by a primary infection in the head in a young, previously healthy person who subsequently develops persistent high fever and disseminated metastatic abscesses, frequently including a septic thrombophlebitis of the internal jugular vein. The main pathogen is Fusobacterium necrophorum, an obligate anaerobic, pleomorphic, gram-negative rod. Clinical microbiologists have a key role in alerting clinicians and advising proper antibiotic treatment when the characteristic microscopic morphology of the pleomorphic F. necrophorum is seen in Gram stains from positive anaerobic cultures of blood and pus. Early diagnosis and prolonged appropriate antibiotic treatment with good anaerobic coverage are crucial to reduce morbidity and mortality. F. necrophorum also causes human necrobacillosis with foci caudal to the head, mainly in elderly patients with high mortality related to age and predisposing diseases, such as cancers of the primary focus.

Lemierre's Syndrome

Lemierre's syndrome is characterized by an oropharyngeal infection followed by internal jugular vein septic thrombophlebitis and metastatic emboli, most often to the lungs and joints. The syndrome is most commonly associated with the anaerobic gram-negative rod Fusobacterium necrophorum. Diagnosis is established with evidence of metastatic infection and internal jugular vein thrombophlebitis. CT is considered the diagnostic procedure of choice. Treatment should include an extended course of a beta-lactamase-resistant antibiotic and surgical drainage of any purulent fluid collection. Anticoagulation remains controversial, and ligation of the internal jugular vein is reserved for patients with persistent sepsis and recurrent emboli. With appropriate therapy, mortality is 4% to 12%; but mortality is increased when therapy is delayed.

Fusobacterium necrophorum infections: virulence factors, pathogenic mechanism and control measures

Fusobacterium necrophorum, a Gram-negative, non-spore-forming anaerobe, is a normal inhabitant of the alimentary tract of animals and humans. Two types of F. necrophorum, subspecies necrophorum (biotype A) and funduliforme (biotype B), have been recognized, which differ morphologically, biochemically, and biologically. The organism is an opportunistic pathogen that causes numerous necrotic conditions (necrobacillosis) such as bovine hepatic abscesses, ruminant foot abscesses and human oral infections. The pathogenic mechanism of F. necrophorum is complex and not well defined. Several toxins, such as leukotoxin, endotoxin, haemolysin, haemagglutinin and adhesin, have been implicated as virulence factors. Among these, leukotoxin and endotoxin are believed to be more important than other toxins in overcoming the host's defence mechanisms to establish the infection. F. necrophorum is encountered frequently in mixed infections and, therefore, synergisms between F. necrophorum and other pathogens may play an important role in infection. Several investigators have attempted to induce protective immunity against F. necrophorum using bacterins, toxoids, and other cytoplasmic components. Generally, none of the immunogens has afforded satisfactory protection against Fusobacterium infections. Because of the unavailability of suitable immunoprophylaxis, the control of F. necrophorum infection has depended mainly on the use of antimicrobial compounds.