Search

The patient is a 66-year-old man with hereditary telangiectasia. He was diagnosed with pulmonary arteriovenous malformation (PAVM), which was revealed by contrast-enhanced chest computed tomography at the age of 65. He developed headache, right homonymous hemianopsia, and right hemiparesis and was admitted to our hospital. Contrast-enhanced magnetic resonance imaging revealed multiple lesions in the left hemisphere, which indicates brain abscesses. Thus, the diagnosis of brain abscess mediated through PAVM was established. Following management with drainage and coil embolization, all neurological symptoms resolved. Therefore, coil embolization should be considered for PAVM at an early stage to prevent brain abscess, even if it is asymptomatic.

Here, we report brain abscess due to Fusobacterium necrophorum (F. necrophorum) in a 78-year-old healthy man. He developed convulsion and did not have any signs of meningitis. Although the brain magnetic resonance imaging findings of the left occipital lobe were typical of a brain abscess, his cerebrospinal fluid examination revealed only slight pleocytosis and mild increase in protein levels. Thus, it was difficult to rule out the possibility of metastatic brain tumor; the patient's condition was provisionally diagnosed as symptomatic epilepsy secondary to brain abscess. His convulsion disappeared soon after administration of antiepileptic, antibacterial, and steroid agents. A craniotomy was performed to evacuate the abscess, and F. necrophorum was identified by culturing the abscess contents. After the operation, he was treated with appropriate antibacterial agents, which resulted in resolution of the brain abscess. Although Fusobacterium species are gram-negative anaerobic bacilli commensal of the human oropharynx, we need to recognize that Fusobacterium species can be a primary pathogen causing brain abscesses and may leave residual neurological sequelae without early appropriate treatment.

A 24-year-old woman presented subdural empyema developing from sinusitis caused by Porphyromonas and Fusobacterium infection. She experienced fever and progressive headache with gradually worsening symptoms. Neurological examination revealed drowsiness and neck stiffness. A CSF examination detected pleocytosis and a low glucose level. Gadolinium-enhanced T1-weighted images from brain MRI showed thickening enhancement at the leptomeninges in the left frontal to temporal lobes and interhemispheric fissure with edema. Based on the diagnosis of bacterial meningoencephalitis and subdural empyema developing from sinusitis primary to odontogenic infection, she received antibacterial chemotherapy with meropenem hydrate and vancomycin hydrochloride, after which motor aphasia and consciousness disturbance occurred. No bacteria were isolated from a trans-sphenoidal biopsy specimen and CSF culture. Molecular typing also was performed by sequencing the 16S ribosomal RNA intergenic spacer region, and Porphyromonas and Fusobacterium were identified. She was given cephalosporin and metronidazol, after which her neurological symptoms and signs gradually lessened. Physicians need to be aware that patients may develop subdural empyema subsequent to sinusitis associated with Porphyromonas and Fusobacterium infection and that amplification and sequence analysis of partial bacterial 16S ribosomal RNA gene should be examined when no bacteria is identified by culture.

We experienced 108 cases of Fusobacterium associated infections, including otolaryngeal, oral, pleuropulmonary, intraabdominal, skin and soft tissue infections, at Aomori Prefectural Hospital during The 5 year-period from 1995 to 1999. A total of 433 organisms, included 113 Fusobacterium spp. (80 Fusobacterium nucleatum, 18 Fusobaterium necrophorum, 5 Fusobacterium varium, 4 Fusobacterium mortiferum, 6 Fusobacterium spp.), were recovered with an average of 4.0 organisms per case of the 108 cases, 68% were mixed aerobic and anaerobic and yielded 185 anaerobic bacteria (2.5 per case) and 137 aerobic bacteria (1.9 per case) with an average of 4.4 per case. The remaining 32% were purely anaerobic and yielded 111 organisms with an average of 3.2 per case, Prevotella spp., Bacteroides fragilis group, Streptococcus milleri group, Enterobacteriaceae, Peptostreptococcus spp. Staphylococcus spp. were most frequently coisolated with Fusobacterium spp.

A patient with epilepsy, 45 years of age, developed a lung abscess due to Fusobacterium nucleatum which was successfully treated with intravenous lincomycin. Quantitative anaerobic cultures of washed sputum proved to be useful in detecting the causative organism.