Acute exacerbation of chronic rhinosinusitis: clinical and microbiological perspectives from a Saudi tertiary care center

BACKGROUND:
Acute exacerbations of chronic rhinosinusitis (AECRS) are increasingly recognized as a distinct clinical entity that significantly impacts quality of life. Despite its clinical relevance, data on its prevalence, clinical characteristics, and underlying bacteriology remain limited.


OBJECTIVES:
This study investigated the clinical features of AECRS and characterized the bacterial profile of middle meatus cultures during exacerbation episodes. Furthermore, characteristics of AECRS were compared across chronic rhinosinusitis (CRS) phenotypes.


DESIGN:
Retrospective cohort study


SETTING:
Single tertiary care referral center, King Saud University Medical City (KSUMC)


PATIENTS AND METHODS:
Medical records from patients with established AECRS with positive middle meatus cultures from 2015 to 2025 were extracted. Data included demographics, CRS phenotype, comorbidities, prior treatments, microbiological findings, and clinical outcomes.


MAIN OUTCOME MEASURES:
Bacterial etiology and clinical characteristics of AECRS across phenotypes, including chronic rhinosinusitis with nasal polyposis, chronic rhinosinusitis without nasal polyposis, and allergic fungal rhinosinusitis.


SAMPLE SIZE:
104


RESULTS:

The study enrolled 104 patients (mean age 39.9 years); 49 (47.1%) had asthma and 21 (20.2%) had aspirin-exacerbated respiratory disease. Endoscopic pus was present in 71 (68.3%), and 77 (74%) had prior sinus surgery. The most common isolates were methicillin-sensitive
Staphylococcus aureus
35 (33%), methicillin-resistant
Staphylococcus aureus
26 (25%), and Pseudomonas species 24 (23.1%). Oral antibiotics were administered in 75 (72.1%) of AECRS episodes, while oral steroids were used in 27 (26%). Clinical improvement following antibiotic therapy was documented in 64 (85.3%) cases. High resistance was observed for ampicillin, penicillin, and oxacillin.



CONCLUSION:
AECRS presents considerable heterogeneity in both clinical presentation and microbiology. Therefore, culture-directed therapy is recommended due to variable antibiotic resistance patterns. Asthma was strongly associated with treatment failure. These findings emphasize the importance of individualized management strategies in AECRS.


LIMITATIONS:
Retrospective design, and single tertiary care center