Allergic Fungal Rhinosinusitis

Allergic fungal sinusitis (AFS) is a subtype of chronic rhinosinusitis with nasal polyps that present with allergic inflammation against fungal antigens. It has some unique features, such as very expanded sinus cavities and a thick, sticky mucin. Oftentimes, patients have an allergy sensitivity and elevated IgE levels in the thousands. Diagnosis is usually made based on the Bent and Kuhn Classification, which is based on clinical/phenotypic criteria. However, Dr. Luong notes that AFS can have geographically diverse presentations. She has noticed that there is a higher AFS prevalence in the South because of the more hot and humid weather. Looking towards the future, she predicts that molecular pathophysiology will be more important in diagnosis, as distinction between the AFS endotypes can serve as targets for therapy. Her research laboratory works on finding these molecular targets.

Next, the doctors discuss typical AFS patient presentations. Dr. Luong usually sees young patients in their 20s with unilateral disease. If they have bilateral disease and other symptoms, it is most likely cystic fibrosis, not AFS. Additionally, AFS patients will have expanded sinuses on CT that may cause a mild headache. Dr. Shah adds that in severe cases, smell and vision loss is possible. However, AFS generally has a low symptom burden because patients get used to the symptoms. Dr. Luong notes that she usually only orders a CT scan. No MRI is needed unless other complications are noted (vision loss, meningitis, skull base / cranial nerve invasion). She orders labs like CBC with differential and total IgE levels.

Next, she shares surgical pearls for treating AFS. She believes that the first surgery is critical to controlling the disease and preventing recurrence. She performs a full FESS on the impacted side and inserts a PROPEL stent that releases steroids locally. Because the sinuses are difficult to clear, she uses angled scopes, warm saline, and the hydrodebrider to complete this task. Although the microdebrider with navigation can be helpful, she doesn’t really use it.

Finally, she shares her steroid regimen. She prescribes at least 40 mg of prednisone in adult patients 3-4 days before surgery. Postoperatively, she prescribes an oral steroid taper starting at 30 mg and decreasing the dosage by 10 mg each week. Additionally, she gives her patients a post-operative nasal rinse that consists of mupirocin and budesonide. She emphasizes the importance of making the postoperative regimen as easy as possible to ensure daily compliance. Finally, the doctors discuss trends in AFS patient follow up.