Fusobacterium necrophorum sepsis after tonsillitis/pharyngitis

Case report: Metagenomics next-generation sequencing in the diagnosis of septic shock due to Fusobacterium necrophorum in a 6-year-old child

Fusobacterium necrophorum (F. necrophorum) infection is rare in pediatrics. In addition, the detection time of F. necrophorum by blood culture is long, and the positive rate is low. Infection with F. necrophorum bacilli usually follows rapid disease progression, resulting in high mortality. In previous reports of F. necrophorum-related cases, the most dangerous moment of the disease occurred after the appearance of Lemierre's syndrome. We report an atypical case of a 6-year-old female patient who developed septic shock within 24 h of admission due to F. necrophorum infection in the absence of Lemierre's syndrome. F. necrophorum was identified in a blood sample by metagenomics next-generation sequencing (mNGS) but not by standard blood culture. The patient was finally cured and discharged after receiving timely and effective targeted anti-infection treatment. In the present case study, it was observed that the heightened virulence and invasiveness of F. necrophorum contribute significantly to its role as a primary pathogen in pediatric septic shock. This can precipitate hemodynamic instability and multiple organ failure, even in the absence of Lemierre's syndrome. The use of mNGS can deeply and rapidly identify infectious pathogens, guide the use of targeted antibiotics, and greatly improve the survival rate of patients.

Not always as simple as a UTI: An atypical case of Lemierre's syndrome, the forgotten disease

A 65-year-old man, who was previously fit and well with no known medical comorbidities, was admitted with symptoms of dysuria, urinary frequency, pyrexia, chills and lethargy. His vitals showed that he was hypotensive, tachycardic and pyrexial. Urine dip was heavily positive for leukocytes and nitrites and had markedly elevated inflammatory markers and mild acute kidney injury. He was commenced on piperacillin/tazobactam. He went on to develop severe left-sided neck swelling and erythema. Ultrasound of the neck with subsequent computed tomography revealed extensive internal jugular vein thrombosis with abscess collection around the vein. Microbiology grew Gram-negative bacilli, later identified as Fusobacterium necrophorum A diagnosis of Lemierre's syndrome was made. The patient was continued on intravenous piperacillin/tazobactam and metronidazole as per sensitivities and later switched to oral metronidazole. He was initiated on warfarin anticoagulation. He made a remarkable recovery and was discharged with outpatient ear, nose and throat and haematology follow-up.

Septic emboli of the lung due to Fusobacterium necrophorum, a case of Lemierre's syndrome

Fusobacterium necrophorum plays a causal role in a rare and life-threatening condition, Lemierre's syndrome. It is characterized by infection involving the posterior compartment of the lateral pharyngeal space complicated by septic suppurative thrombophlebitis of the internal jugular vein with F. necrophorum bacteremia and metastatic abscesses, primarily to the lung and pulmonary septic emboli. Herein, we present a very rare case of oropharyngeal infection complicated by Lemierre's syndrome with characteristic septic emboli to the lungs presenting as sore throat in a previously healthy patient. A 23-year-old woman presented with sore throat and was found to be in sepsis and acute kidney injury. She was found to have septic emboli in lung and Streptococcus anginosus and F. necrophorum in blood. She was diagnosed with Lemierre's syndrome and successfully treated with antibiotics. Lemierre's syndrome should be included in the differential diagnosis in young patients who deteriorate in the setting of a sore throat. If the suspicion is high, throat swabs from young patients with nonstreptococcal group A tonsillitis should be cultured anaerobically on selective medium to detect the presence of F. necrophorum. While clinicians of the infectious disease team may be familiar with this condition other departments including internal medicine and critical care team may less so. Unless clinicians are aware of this syndrome, diagnosis and treatment can be delayed leading to higher morbidity and mortality.