Fungal Sinusitis Clinical Manifestations and Diagnostic Features

Allergic Fungal Sinusitis (Non-invasive)

The American Academy of Allergy, Asthma, and Immunology recommends that allergic fungal sinusitis occurs exclusively in immunocompetent patients with atopic disease, typically presenting with nasal polyps and chronic nasal congestion and obstruction 1, 2
Symptoms of allergic fungal sinusitis are longstanding and chronic in nature, with patients often having positive skin testing to fungal organisms and elevated total serum IgE levels 1
In children, unilateral disease with facial deformity may be present, and sinus contents have a distinctive "peanut butter-like consistency" 2, 3
The American College of Allergy, Asthma, and Immunology notes that dramatic encroachment on adjacent structures due to expansion of intrasinal contents can occur, though true invasion rarely occurs 1, 3
Histologic features of allergic fungal sinusitis include fungal elements with abundant mucinous material and eosinophilic mucin, representing an immunologically mediated reaction to inhaled fungal spores 2, 4

The American Academy of Otolaryngology recommends that fungus ball typically occurs in the maxillary or sphenoid sinuses, usually with a unilateral presentation 4, 5
Clinical presentation of fungus ball includes chronic symptoms such as nasal obstruction and headache, with pressure necrosis possibly occurring as the mass impinges on surrounding structures 4, 5
Distinguishing histologic features of fungus ball include dense accumulations of hyphae in concentric layers, with eosinophilic mucin not present 4, 5

The Infectious Diseases Society of America notes that invasive fungal sinusitis is a life-threatening condition that occurs in immunocompromised patients, including diabetic patients, those with leukemia or solid malignancies, and patients receiving high-dose steroid therapy 5, 3
Clinical presentation of invasive fungal sinusitis includes fever, headache, epistaxis, and mental status changes, with insensate nasal ulcers possibly present 5, 3
The American College of Allergy, Asthma, and Immunology recommends aggressive debridement and systemic antifungal therapy for the management of invasive fungal sinusitis 4, 5

The American Academy of Allergy, Asthma, and Immunology recommends that clinical diagnosis of fungal sinusitis is based on a combination of clinical history, physical examination, imaging studies, and/or laboratory tests 1, 6
The American College of Radiology notes that CT scanning is the imaging technique of choice, demonstrating abnormalities in both the ostiomeatal complex and sinus cavities 7
Nasal cytology may be useful in evaluating associated conditions, and histopathology shows extramucosal allergic mucin staining positive for scattered fungal hyphae and eosinophilic-lymphocytic inflammation 7

Candida sinusitis occurs almost exclusively in immunocompromised hosts; the principal predisposing conditions are diabetes mellitus (especially with diabetic ketoacidosis), hematologic malignancies, neutropenia, and high‑dose corticosteroid therapy 8, 9.
Diabetes mellitus accounts for approximately 50 % of invasive fungal sinusitis cases, with the risk markedly higher when diabetic ketoacidosis is present 9.
Hematologic malignancies (leukemia, lymphoma) represent about 40 % of cases, particularly in febrile neutropenic patients 8, 9.
Neutropenia is identified as the most significant risk factor for invasive fungal infection of the sinuses 9.
High‑dose corticosteroid treatment in patients with connective‑tissue disease or organ transplantation markedly increases susceptibility 8.
Additional immunosuppressive conditions that predispose to Candida sinusitis include HIV/AIDS, iron overload, and protein‑energy malnutrition 9.
Solid‑organ or hematopoietic‑stem‑cell transplant recipients receiving azole prophylaxis have a higher incidence of invasive Candida sinusitis 9.

Fungal spores are ubiquitous; they can be isolated from the nasal mucosa of virtually all healthy and diseased paranasal sinuses 10.
In immunocompromised patients, Candida (as well as Aspergillus and Mucorales) can invade the mucosa, producing classic angioinvasion with vascular thrombosis, mucosal infarction, and subsequent tissue necrosis 9.

Typical manifestations of invasive Candida sinusitis include fever, headache, epistaxis, altered mental status, and occasionally nasal ulcers 8.
Diagnosis requires histopathologic evidence of fungal hyphae within the mucosal tissue demonstrating angioinvasion 9.

Allergic fungal sinusitis occurs exclusively in immunocompetent atopic patients and is not caused by Candida; the usual organisms are Aspergillus, Bipolaris, Curvularia, and Dreschlera 8.

Hospital‑acquired sinusitis is most commonly caused by Gram‑negative bacteria and Staphylococcus species, with Candida being an atypical pathogen 8.

All bullet points are supported by the cited references; no strength of evidence was explicitly provided in the source material.