Staphylococcus aureus brain abscess due to chronic sinusopathy and mastoiditis: a case report
Authors: Gomes Fernanda Klein , Mathias Antonio Sérgio , Kume Andressa Naomi , Cesar Eda Silva , Nogueira Gabriel Henrique Silva , Cerqueira Nicolas Kipman , Castilho Matheus Santos 
Published: July 2023

Introduction: A brain abscess is an intraparenchymal collection of pus and a life-threatening infection. Despite the advancements in imaging and diagnostic techniques, observational studies suggest mortality rate still remains high. The clinical presentation usually includes fever, headache and focal neurologic deficits. About 90% result from pericranial infection such as sinusitis, mastoiditis and otitis media, and many are hematogenous borne such as bacterial endocarditis. Bacteroides, Peptostreptococcus and Streptococcus are the most pathogens identified in brain abscesses due to contiguous spread from pericranial infection, while Peptostreptococcus and Streptococcus are the ones in patients with cardiac origin. Staphylococcus is common in posttraumatic and postoperative cases. The treatment must be individualized according to the pathogen and the patient. Initial therapy should include broad spectrum antibiotics. Most pyogenic abscess also requires a surgical intervention. The aim is to describe a brain abscess case as a result of an untreated chronic sinusopathy and mastoiditis. Case report: A 31-year-old man presented to the Emergency Department of our hospital with fever and progressive cognitive decline, which had been worsened the last five days. Associated with headache for over a year, that didn’t get relieved with analgesics, chronic cold and right otorrhea. His past medical history included splenectomy as a kid with immunizations up to date and a chronic sinusopathy and mastoiditis without any treatment. His social history included chronic alcohol consumption and smoking. Admitted with normal ranges of vital signs and physical examination, except for his neurological examination which showed notable disorientation. Complete blood count and metabolic panel results were normal. Serologic testing for human immunodeficiency virus and hepatitis were negative. Head computed tomography scan revealed a large mass (64 x 37 mm) involving the left frontal lobe with edema and 9 mm midline shift. After admission, empirical parenteral antibiotics were started with ceftriaxone 2 g, oxacillin 2 g, metronidazole 500 mg and the patient underwent immediate neurosurgical drainage of the large abscess. The cerebrospinal fluid cultures were positive for Staphycoccus aureus. The patient had previous brain magnetic resonance imaging that indicated a chronic sinusopathy of all four paranasal sinuses and a right mastoiditis. Since the normality of blood exams and no better hypothesis to explain the abscess, the chronic sinusopathy had been considered the main cause for the patient’s outcomes. The patient underwent a sinusectomy. After five days, the patient was discharged from the Intensive Care Unit due to better clinical evolution. The patient signed the informed and consent form to participate in this research. Conclusion: As the brain abscess continues with a high mortality rate, it could be important to focus attention on recognizing the risk factors and early treat them, including sinusopathy and mastoiditis, in order to avoid severe complications such as brain abscess and eventually prevent the occurrence of critical outcomes.