Bumping Into Doors: A Case Report of Brain Abscess as a Complication of Pulmonary Arteriovenous Malformation

Cerebral abscess is an infection of the central nervous system that can cause a variety of neurologic signs. The majority of infections are caused by distant haematogenous spread, neurotrauma, surgery, or contiguous infections. Another rare source of a brain abscess is a pulmonary arteriovenous malformation (PAVM). Late diagnosis and neurological complications associated with brain abscesses can cause significant morbidity or even mortality. We present the case of a 75-year-old Caucasian male with complaints of subfebrillitas, headache, and difficulty in estimating distances. A diagnosis of brain abscess was made. The abscess was drained, and ceftriaxone plus metronidazole was initiated. After the cultures were positive for <i>Streptococcus anginosus</i> and <i>Fusobacterium</i>, the therapy was de-escalated to penicillin G and metronidazole. In search of a focus, a PAVM was identified and subsequently embolised. Brain abscess is a relatively rare condition. The prevalence of PAVMs is also considered uncommon. The majority of cases is linked to hereditary haemorrhagic telangiectasia (HHT), an autosomal dominant hereditary disease, but PAVMs can also occur as a single-standing problem. Neurological events such as cerebral abscess, stroke, or migraine may occur in some cases of PAVMs. To prevent complications, embolisation of every radiographically visible PAVM needs to be considered. Moreover, PAVMs should be considered in the search for the aetiology of a brain abscess when routine investigations fail to detect other causes. The coexistence of HHT in every patient with PAVMs also needs to be considered.