Fusobacterium nucleatum Bacteremia Presenting with Portal Vein Thrombosis: An Abdominal Lemierre Syndrome?

Fusobacterium nucleatum Bacteremia Presenting as Isolated Superior Mesenteric Vein Thrombophlebitis

Fusobacterium nucleatum (F. nucleatum) is a commensal Gram-negative anaerobic bacterium that lives in the oral cavity and gastrointestinal tract of humans. While it is a regular resident of the human oral cavity, F. nucleatum has been implicated in various infections and inflammatory conditions. This case report highlights an unusual association between F. nucleatum and isolated superior mesenteric vein (SMV) thrombosis.

Gastrointestinal Variant of Lemierre's Syndrome: A Systematic Review and Comprehensive Analysis of 36 Case Reports

Background

A gastrointestinal (GI) variant of Lemierre's syndrome (LS) involving Fusobacterium species causing pylephlebitis and possibly liver abscesses was recently identified. This systematic review aims to summarize the literature on this variant.

Methods

PubMed, Embase, Scopus, and Cochrane databases were searched up to November, 2nd, 2023 for case reports or case series detailing the GI variant of LS. Data regarding demographics, clinical features, and management were extracted. Descriptive statistics were used for analysis, including means, standard deviations, and percentages.

Results

The cohort included 36 patients (mean age 50.8 years; predominantly men 72%). Positive blood cultures were detected in 88.8% of cases, primarily growing Fusobacterium nucleatum (47.2%) and Fusobacterium necrophorum (33.3%). The GI tract was the primary infection source (58.3%), mostly related to diverticular disease (25%). Common manifestations were fever (86.1%), abdominal pain (72.2%), and leukocytosis (86.1%). Thrombosis involved the portal vein in 77.7%, with isolated portal vein thrombosis (PVT) (44.4%) and PVT extending to the superior mesenteric vein (30.5%). Liver abscesses were detected in 50% of cases, with positive aspirate cultures in 92.3%. Treatment included penicillin/penicillin-lactamase inhibitors alone (17%) and ertapenem alone (17%). Abscess drainage (13/18) resulted in complete/near-complete resolution in 83%. Long-term anticoagulation therapy was given in 75% of cases, commonly using vitamin K antagonists (59.2%). No deaths occurred.

Conclusion

The GI variant of LS should be considered in patients with abdominal pain, fever, leukocytosis, and portal/superior mesenteric vein thrombosis. Identifying Fusobacterium species in blood cultures and liver abscesses further supports the diagnosis. Management involves antibiotic therapy, abscess drainage, and long-term anticoagulation.

Fusobacterium nucleatum Promotes Megakaryocyte Maturation in Patients with Gastric Cancer via Inducing the Production of Extracellular Vesicles Containing 14-3-3ε

Fusobacterium nucleatum colonization contributes to the occurrence of portal vein thrombosis in patients with gastric cancer (GC). However, the underlying mechanism by which F. nucleatum promotes thrombosis remains unclear. In this study, we recruited a total of 91 patients with GC and examined the presence of F. nucleatum in tumor and adjacent non-tumor tissues by fluorescence in situ hybridization and quantitative PCR. Neutrophil extracellular traps (NETs) were detected by immunohistochemistry. Extracellular vesicles (EVs) were extracted from the peripheral blood and proteins in the EVs were identified by mass spectrometry (MS). HL-60 cells differentiated into neutrophils were used to package engineered EVs to imitate the EVs released from NETs. Hematopoietic progenitor cells (HPCs) and K562 cells were used for megakaryocyte (MK) in vitro differentiation and maturation to examine the function of EVs. We observed that F. nucleatum-positive patients had increased NET and platelet counts. EVs from F. nucleatum-positive patients could promote the differentiation and maturation of MKs and had upregulated 14-3-3 proteins, especially 14-3-3ε. 14-3-3ε upregulation promoted MK differentiation and maturation in vitro. HPCs and K562 cells could receive 14-3-3ε from the EVs, which interacted with GP1BA and 14-3-3ζ to trigger PI3K-Akt signaling. In conclusion, we identified for the first time that F. nucleatum infection promotes NET formation, which releases EVs containing 14-3-3ε. These EVs could deliver 14-3-3ε to HPCs and promote their differentiation into MKs via activation of PI3K-Akt signaling.

Fusobacterium bacteremia presenting with inferior mesenteric vein thrombosis

Isolated mesenteric vein thrombosis associated with Fusobacterium is rare. Physicians should be aware regarding the association of Fusobacterium with thrombosis at various sites.

Pylephlebitis: A Systematic Review on Etiology, Diagnosis, and Treatment of Infective Portal Vein Thrombosis

Pylephlebitis, defined as infective thrombophlebitis of the portal vein, is a rare condition with an incidence of 0.37-2.7 cases per 100,000 person-years, which can virtually complicate any intra-abdominal or pelvic infections that develop within areas drained by the portal venous circulation. The current systematic review aimed to investigate the etiology behind pylephlebitis in terms of pathogens involved and causative infective processes, and to report the most common symptoms at clinical presentation. We included 220 individuals derived from published cases between 1971 and 2022. Of these, 155 (70.5%) were male with a median age of 50 years. There were 27 (12.3%) patients under 18 years of age, 6 (2.7%) individuals younger than one year, and the youngest reported case was only 20 days old. The most frequently reported symptoms on admission were fever (75.5%) and abdominal pain (66.4%), with diverticulitis (26.5%) and acute appendicitis (22%) being the two most common causes. Pylephlebitis was caused by a single pathogen in 94 (42.8%) cases and polymicrobial in 60 (27.2%) cases. However, the responsible pathogen was not identified or not reported in 30% of the included patients. The most frequently isolated bacteria were Escherichia coli (25%), Bacteroides spp. (17%), and Streptococcus spp. (15%). The treatment of pylephlebitis consists initially of broad-spectrum antibiotics that should be tailored upon bacterial identification and continued for at least four to six weeks after symptom presentation. There is no recommendation for prescribing anticoagulants to all patients with pylephlebitis. However, they should be administered in patients with thrombosis progression on repeat imaging or persistent fever despite proper antibiotic therapy to increase the rates of thrombus resolution or decrease the overall mortality, which is approximately 14%.

Suppurative Thrombosis of the Portal Vein (Pylephlebits): A Systematic Review of Literature

Suppurative portal vein thrombosis (pylephlebitis) is an uncommon condition usually associated with an intra-abdominal infection or inflammatory process. In this study, we aimed to synthesize data on previously published cases according to the PRISMA guidelines. A total of 103 patients were included. Patients were more commonly male (71.8%) and had a mean age of 49 years. The most common infection associated with pylephlebitis was diverticulitis (n = 29, 28.2%), and Escherichia coli was the most isolated pathogen (n = 21, 20.4%). Blood cultures were positive in 64 cases (62.1%). The most common site of thrombosis was the main portal vein (PV) in 59 patients (57.3%), followed by the superior mesenteric vein (SMV) in 40 patients (38.8%) and the right branch of the PV in 30 patients (29.1%). Sepsis developed in 60 patients (58.3%). The mortality rate in our review was 8.7%, and independent risk factors for mortality were the presence of pertinent comorbidities (OR 5.5, p = 0.02), positive blood cultures (OR 2.2, p = 0.02), and sepsis (OR 17.2, p = 0.049).

Fusobacterium nucleatum: More Than Just an Oral Anaerobe

Fusobacterium nucleatum is a strict anaerobe that is indigenous to the human oral cavity, where it coexists with more than 500 other species. It is associated with paranasal sinus, odontogenic, and pulmonary infections. In literature, cases of Fusobacterium nucleatum are rare. Here we report a case of a patient with multiple brain abscesses caused by Fusobacterium nucleatum. This case report looks to assist clinicians in determining the true etiology of this organism, which can change patient management based on the current literature review and similar case studies.

Pylephlebitis Caused by Fusobacterium nucleatum in a Septuagenarian Healthy Caucasian Male: Atypical Presentation of Lemierre’s Syndrome

Lemierre's syndrome (LS) is characterized by thrombophlebitis of the internal jugular vein caused primarily by Fusobacterium necrophorum. LS is usually suspected in fit young adults with prolonged or prior pharyngeal infection. Atypical Lemierre's syndrome is commonly defined as Fusobacterium-associated thrombophlebitis outside the head-neck veins and usually occurs in older patients than typical Lemierre's syndrome. Here we present a case of atypical LS in a septuagenarian healthy Caucasian male with no prior history of pharyngitis and in whom both computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated partial portal vein thrombosis associated with Fusobacterium nucleatum. This case report confirms previous reports of Fusobacterium nucleatum-associated LS variants presenting with abdominal vein thrombosis and illustrates clinical recovery after a combination of anticoagulation and antibiotic therapy.

A Rare Twist of the Forgotten Disease: A Case of Fusobacterium necrophorum Sepsis with Portomesenteric Thrombosis and a Review of the Literature

Abdominal variants of Lemierre's syndrome presenting with pylephlebitis are rare, and the role of anticoagulation in treatment is controversial. We hereby report a case of pylephlebitis secondary to F. necrophorum bacteremia in a 57-year-old female originating from bacterial translocation secondary to colitis, who developed a favorable outcome with prompt treatment with antibiotics and anticoagulation. We also perform a literature review on similar cases in the literature and discuss management options of this rare but potentially fatal complication.

Abdominal Variant of Lemierre's Syndrome in a Patient with Pancreatic Adenocarcinoma

Lemierre’s syndrome is an illness characterized by internal jugular vein thrombophlebitis related to infectious agents, primarily Fusobacterium necrophorum. These bacteria, residing in both the oropharynx and the gastrointestinal tract, may lead to pylephlebitis, a serious condition that could result in the development of hepatic abscesses. This manifestation of the disease is regarded as the abdominal variant of Lemierre’s syndrome. Patients with gastrointestinal malignancies, especially those who undergo surgeries, are susceptible to the abdominal variant of Lemierre’s syndrome. Timely diagnosis is required to avoid the life-threatening complications of the abdominal variant of Lemierre’s syndrome. Diffusion-weighted magnetic resonance imaging (MRI) might be very useful in differentiating this disease from liver metastasis in patients with malignancies. Radiologists and clinicians need to be aware of this challenging condition to prevent misdiagnosis, since prompt treatment is often lifesaving.

An unusual case of abdominal pain and splenomegaly in a paediatric patient

Fusobacterium species are members of the oral microbiota and have been found to cause a wide spectrum of opportunistic infections. We describe the case of a previously healthy teenager with a large splenic abscess secondary to Fusobacterium nucleatum, successfully managed with percutaneous drainage and intravenous antibiotics. Identification of the organism was achieved using anaerobic culture of the aspirated fluid and matrix-assisted laser desorption/ionization time of flight, later confirmed by 16S ribosomal RNA metagenomic sequencing of the fluid. Fusobacteria are typically associated with oropharyngeal infections but are very rarely implicated in splenic abscesses. Aerobic and anaerobic blood cultures should be drawn when an intra-abdominal infection is suspected in a paediatric patient, and empiric antimicrobial therapy should be administered with coverage for gram-positive, gram-negative, and anaerobic bacteria.

Sporadic Fusobacterium Bacteremia as an Atypical Cause of Acute Hepatitis in a Young Caucasian Woman

Fusobacterium species are gram-negative anaerobic non-spore-forming bacteria, which colonize mucous membranes in humans. Over the recent decade, the significance of these organisms has been increasingly recognized. We describe a rare case of acute hepatitis, which was found to be likely due to Fusobacterium nucleatum, grown on blood culture. In our case, the hepatitis caused by this microorganism resolved completely without any long-term sequelae to the liver, through conservative management namely intravenous antibiotics and supportive therapy only. This case highlights that early detection and prompt treatment in a case of acute hepatitis resulted in a good outcome. In addition, this case also illustrates that the differential diagnosis can be varied in cases of acute hepatitis.

Fusobacterium bloodstream infections: A literature review and hospital-based case series

BACKGROUND

Infections with Fusobacterium, an anaerobic bacterium, have various clinical presentations, including bacteremia and Lemierre syndrome. Here, we report a case series of Fusobacterium bacteremia (FBB) from the largest academic center in Riyadh, Saudi Arabia, and provide a review of cases in the available literature.

METHOD

Records were retrospectively reviewed for all patients with at least one blood culture positive for Fusobacterium spp. admitted at King Khalid University Hospital, Riyadh, Saudi Arabia, between May 2015 to April 2019.

LITERATURE REVIEW

We conducted a MeSH Search on MedLine using the following terms: ("Bacteremia"[Mesh]) AND "Fusobacterium"[Mesh] for studies conducted from January 1, 1990, until March 30, 2019, excluding articles that lacked adequate clinical or microbiological details for individuals patients. Odds ratios and results of Chi-Square testing obtained in SPSS (Version 23.0, SPSS, Inc., Chicago, IL, USA) were considered statistically significant at p-values < 0.05.

RESULTS

Seven cases from our center and 205 cases from the literature were reviewed in this first reported case series for the region. Our patient series was similar to previous ones in terms of median age (45 vs. 45.5 years) and male predominance (85% vs. 65.9%). The species of Fusobacterium cultured from our cases were F. nucleatum (4 cases), F. varium (1 case), F. mortiferum (1 case), and one that could not be identified to the species level (1 case). We also report one case of FBB with renal vein thrombosis resembling that of atypical Lemierre syndrome. Analysis of literature cases revealed that bacteremia caused by the species most commonly associated with FBB, F. necrophorum, tended to be present in patients less than 40 years of age and be associated with head and neck infections and other complications, whereas F. nucleatum tended to affect people more than 40 years of age and be associated with mortality.

CONCLUSION

Although FBB is rarely reported in the literature, this case series and review of the literature suggests it is associated with morbidity and mortality. The type and duration of therapy used in these cases are underreported. Further research is needed to determine the most appropriate screening approach for FBB-associated complications and explore the relationship between FBB and specific malignancies, as well as optimal treatment type and duration.

Small Intrahepatic Vein Budd-Chiari Syndrome Complicated by Fusobacterium nucleatum Peritonitis

Budd-Chiari syndrome is a rare disorder with significant liver-related complications. We present a 28-year-old woman with a 1-month history of weight loss and ascites. Hepatic venogram showed patent hepatic veins and inferior vena cava; however, there was an increased hepatic venous pressure gradient, which is clinically significant for portal hypertension. Hereditary and acquired thrombophilia workup was unrevealing. During admission, she developed peritonitis with Fusobacterium nucleatum and was treated with piperacillin-tazobactam. Liver biopsy showed vascular changes with features of venous outflow obstruction, and she was diagnosed with “small hepatic vein” Budd-Chiari syndrome. She was treated with transjugular intrahepatic portosystemic stent-shunt and tinzaparin, with significant clinical improvement.