Introduction

Sinusitis refers to inflammation of the paranasal sinus mucosa [1]. It may occur as acute, chronic or recurrent condition, depending on symptom duration [1]. According to EPOS 2020, acute sinusitis lasts less than twelve weeks, while chronic sinusitis lasts twelve weeks or longer [1, 2]. Typical symptoms include nasal congestion, discharge, facial pain and hyposmia [1]. Sinusitis is most commonly caused by viruses, while bacteria trigger only 2% of the infections [1]. It is estimated that in nearly 4% of hospitalized patients sinusitis is invasive. Consequences of this condition are severe, including brain abscesses, epidural empyema, cavernous sinus thrombosis and orbital cellulitis [1].

We report the case of a 59-year-old patient with chronic invasive bacterial pansinusitis and a brain abscess, without prior medical history. Initially, a variety of neurological conditions was suspected as the patient had had four episodes of epileptic convulsions before he was admitted to the hospital.

Case report

A 59-year-old man with no relevant medical history presented to the Emergency Department after four epileptic seizures. The patient reported a week of dull frontal headache and long-term untreated nasal obstruction. Laboratory findings revealed leukocytosis (WBC 18.48 g/l) and elevated C-reactive protein (CRP 7.34 mg/l). The patient was immediately treated with diazepam.

An urgent non-contrast computed tomography (CT) demonstrated massive inflammatory changes in the paranasal sinuses with bone destruction of the frontal sinus wall and suspected brain involvement. Fungal sinusitis was initially suspected due to hyperdense homogeneous secretions. Subsequent magnetic resonance imaging (MRI) confirmed a left frontal brain abscess (18 × 11 mm) with surrounding oedema (Figures 1, 2).

The patient was transferred to the otolaryngological department. Upon admission, intravenous antibiotic (third-generation cephalosporin) was administered and diazepam was continued. Subsequently, the patient underwent functional endoscopic sinus surgery (FESS) with bilateral maxillary, ethmoidal, and frontal sinus drainage. A large amount of purulent material was evacuated and tissue samples were sent for histopathological and microbiological examination. A left-sided antrochoanal polyp obstructing the choana and pharynx was also removed.

Histology confirmed chronic inflammation without fungal elements. Microbiological cultures identified Streptococcus intermedius (susceptible to ceftriaxone). Despite extensive sinus surgery, imaging revealed a persistent brain abscess that required neurosurgical intervention. The patient subsequently underwent left frontal craniotomy with abscess drainage and fistula closure.

Postoperatively, the patient received targeted intravenous antibiotics, including third-generation cephalosporins and metronidazole, as well as antiepileptic prophylaxis with sodium valproate. Recovery was uneventful and seizure-free. Follow-up imaging showed abscess resolution and reduced oedema. The patient was discharged in satisfactory condition, with scheduled follow-up in otolaryngology and neurosurgery clinics.

Discussion

In this case, diagnosis was challenging due to absent medical history and limited symptoms. Seizures and frontal headache initially suggested a neurological cause. Microbiological examination was conducted. Streptococcus intermedius was isolated, confirming chronic invasive bacterial sinusitis. It is an uncommon causative organism, as most frequently the condition is caused by Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis and Staphylococcus aureus [1].

FESS was chosen as the standard surgical approach for complicated sinusitis. It can significantly improve quality of life and mitigate symptoms of the disease by reclaiming appropriate aeration of the sinuses and widening sinus ostia [3]. FESS was chosen as the main treatment method also due to the necessity to excise a remarkable number of nasal polyps, as well as a singular antrochoanal polyp [3]. The polyp, which is defined as a benign lesion, originating from the mucosa of the maxillary sinuses, closed the choanae and pharynx on the left side [4]. In this case, conservative medical treatment would be insufficient. Histology of FESS specimens confirmed chronic sinusitis with polyps.

Negligence of chronic sinusitis caused extension of bacterial infection to the left frontal lobe. Due to the significant size of the sinogenic brain abscess (greater than 1 cm), neurosurgical intervention was indicated [5]. Postoperatively, targeted therapy with third-generation cephalosporin was continued [5]. Antiepileptic therapy was also implemented to prevent recurrent seizures, a recognized complication of brain abscesses [6, 7]. The patient’s favourable clinical outcome highlights the importance of early medical intervention including surgical approach.

Conclusions

Chronic sinusitis, though often considered benign, may lead to life-threatening complications such as a brain abscess when neglected. This case underscores considering sinonasal infections in the differential diagnosis of new-onset seizures, especially when chronic nasal obstruction is present. Prompt imaging, surgery, and interdisciplinary care with targeted antibiotics are essential for favourable outcomes. Early recognition and treatment of chronic sinus disease may prevent severe intracranial complications.

Funding

No external funding.

Ethical approval

Not applicable.

Conflict of interest

The authors declare no conflict of interest.

References