Life-Threatening Orbital and Intracranial Sequelae of Odontogenic Sinusitis: 3 Complex Cases

BACKGROUND Odontogenic sinusitis (ODS) is increasingly recognized as a distinct cause of secondary rhinosinusitis with an anaerobe-predominant microbiology and a propensity for severe extrasinus complications. Among serious sequelae are orbital and intracranial infections, which can be vision- or life-threatening. CASE REPORT We report 3 cases illustrating the spectrum of complicated ODS. The first patient, a 23-year-old man, developed bacterial meningitis and a brain abscess that required urgent endoscopic sinus surgery with dental extraction. Cultures identified Acinetobacter pittii in dental and sinus sources. Treatment was carried out with broad-spectrum, anaerobe-targeted antimicrobial therapy with subsequent culture-directed adjustment. The second case, a 27-year-old man, presented with a large left frontal abscess complicated by intraventricular rupture and sigmoid sinus thrombosis. He underwent bilateral endoscopic sinus surgery with extraction of the causative tooth and received prolonged antimicrobial therapy. Cultures yielded Streptococcus constellatus, with subsequent directed intravenous antimicrobial therapy for 8 weeks and recovery without neurological sequelae. The third case, a 28-year-old man, had orbital cellulitis with subperiosteal phlegmon secondary to periapical dental infection. He was treated with dental extraction and antibiotics as he did not consent to surgery. Microbiological analysis revealed Corynebacterium durum. He recovered without ocular impairment. CONCLUSIONS These cases emphasize the importance of considering an odontogenic source in unilateral sinus disease, especially when complicated by orbital or neurological signs. Management requires early recognition, imaging, and a multidisciplinary approach combining broad-spectrum antibiotics, surgical drainage of affected sinuses, and definitive dental treatment. Awareness of the distinct pathogenesis and microbiology of ODS is essential to prevent diagnostic delay and optimize patient outcomes.