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The medical and surgical treatment of fungal sinusitis is dependent on the manifestation of the fungal sinusitis along the immunologic spectrum.1 This chapter will review in depth the management of allergic fungal sinusitis (AFS). This management is both surgical and medical. Recurrence rates of AFS following surgery alone are high.² Medical adjuncts that definitely or possibly reduce this recurrence rate include steroid therapy, antifungal therapy, and immunotherapy.³ The evidence and recommended protocols will be reviewed.

The medical and surgical management of the other manifestations of fungal sinusitis, invasive (acute and chronic), granulomatous invasive, and fungus ball differ from AFS and will be briefly detailed to differentiate their management from AFS.

Management of the Various Manifestations of Fungal Sinusitis

Invasive fungal sinusitis, which occurs primarily in immunocompromised individuals, requires immediate surgical intervention to confirm the diagnosis and exenterate nonviable tissue.^4,5 Equally important is reversal of the source of the immunocompromise, if possible, with systemic and topical antifungal agents. Aspergillus species are the most common infecting agents; however, rare nonpathogenic fungi can also on occasion become invasive. Fungal cultures are necessary to determine sensitivity to the antifungal agents. Table 9–1 lists some common invasive fungal pathogens and the recommended systemic antifungal therapy.

Prognosis in invasive fungal sinusitis is linked directly to the ability to reverse the underlying source of immunocompromise. Mucormycosis, a term applied to infections from any of several species within the class of Zygomycetes, including Mucor and Rhizopus, should be considered a possible diagnosis in any poorly controlled diabetic with sinusitis.⁵ The likelihood of recovery in diabetics with mucormycosis is 80%, and leukemics in relapse survive less than 20% of the time.⁶ This difference in prognosis reflects the ability to reverse poorly controlled diabetes more easily than leukemia. Every attempt to provide the severely immunocompromised with a fungal free environment until recovery of their immune function should be made.⁷

Endoscopic sinus techniques can be utilized in invasive fungal sinusitis,⁸ except in situations where thrombocytopenia or other coagulopathies exist. Although difficult-to-control bleeding makes any surgery difficult, it makes endoscopic techniques impossible. If surgery must be done, then correction of the coagulopathy for the time of surgery is imperative.

Occasionally invasive fungal infections of the paranasal sinuses occur in immunocompetent or mildly immunocompromised individuals. This is termed chronic fungal sinusitis or granulomatous invasive sinusitis, depending on the histopathology.⁴ These infections may progress slowly yet relentlessly, and in some cases will be refractory to surgery and prolonged antifungal therapy.

Fungus balls, matted clumps of hyphae lying within the dark confines of a sinus cavity, occur in the immunocompetent and may be asymptomatic and discovered incidentally or the cause of pain, drainage, or congestion.⁹ The mean age is in the mid 60s, and the most frequent sinus involved is the maxillary sinus, followed by the sphenoid. Ethmoid sinus involvement is usually associated with maxillary sinus involvement, and frontal sinus involvement is rare. There is one case report in which a fungus ball became invasive following immunosuppresion of the patient for a kidney transplant. In the immunocompetent patient, no antifungal therapy is needed, and the disorder is resolved with surgical removal.10 Endoscopic techniques lend themselves readily to removal of fungus balls. Endoscopic irrigation can be helpful in washing out the fungus. Occasionally, a Caldwell-Luc approach is required in maxillary infestations. Recurrence is uncommon. Frontal sinus fungus balls can be approached endoscopically endonasally, with a frontal sinus trephination, to provide a port to irrigate the fungus. Alternatively, a frontoethmoidectomy via a Lynch incision may be used.

¹ Fungi susceptible to amphotericin B have also been treated with topical ampthotericin B. is mixed with 10 mL of sterile water. A nasal spray can be dosed as two sprays two to six times per day. A 0.5% nasal spray is produced when a 50 mg vial of IV amphotericin B The solution is stable for 7 days but must be refrigerated and kept from light. There are no studies confirming the efficacy of nasal amphotericin; however, it has been used to prevent fungal infections in susceptible patients.

2 Liver function tests should be performed in patients taking itraconazole for more than 4 weeks.

Saprophytic fungal growth refers to the spores that grow on small crusts of mucus within the nasal cavity. This is more common after endoscopic sinus surgery, when mucociliary clearance pathways may be disrupted, leading to small mucous crusts residing on the middle turbinate or within the ethmoid cavity. These small growths of hyphae can be the early form of a fungus ball, but generally they are easily blown out by the patient or aspirated away at the time of nasal endoscopic evaluation. No further treatment is required. If the problem is recurrent, then the patient can be instructed in weekly saline irrigation of the nose with a baby bulb syringe or a powered water irrigation system.

The remaining sections of this chapter will deal with the management of AFS, which differs dramatically from the treatment of other manifestations of fungal sinusitis. Table 9–2 summarizes the diagnostic criteria and management of the various forms of fungal sinusitis.

Management of AFS

Preoperatively, one suspects the existence of AFS because of the clinical characteristics outlined in Chapter 4. Ultimately, diagnosis requires surgery with histopathologic confirmation.¹¹ Nevertheless, recurrence is common. In treating the patient with AFS, conservative and nonmutilating surgical debridement of the affected sinuses is the primary modality of therapy. AFS is by and large a non-life-threatening disease, and one should not inflict potentially life-threatening procedures onto the disease process. The “cure” should not be worse than the disease. Removal of all the fungal-laden allergic mucin is important. If the fungal-laden mucin is not removed, then the disease persists. It may be quiescent during systemic steroid therapy, but it will almost always recur.² If removal of all fungal-laden allergic mucin is accomplished, the patient may be temporarily cured, but he or she faces the prospect of recurrent exposure to the ubiquitous fungal spores and recurrence of AFS because the underlying allergic predisposition persists. Thus, medical adjuncts are important in reducing recurrence of disease following surgery. These will be discussed following the section on special considerations in the surgery of AFS.

Surgery in AFS

Endoscopic surgical techniques were developed in the mid-1970s and introduced in the United States in the mid-1980s. Up until then, the surgical approach in AFS usually required external approaches, such as Caldwell-Lucs, external ethmoidectomies, and frontal sinus obliterative procedures. By and large, these procedures have all been replaced with endoscopic sinus surgery.^12–14

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