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Fungal SinusitisDr Vasanthika Sanjeewanie Thuduvage Consultant ENT and Head & Neck Surgeon Senior Lecturer / Faculty of Medicine KDU
Fungal Sinusitis400,000 known fungal species or
which 400 are human pathogens and 50 of which cause systemic or CNS infection
Broadly categorized into invasive and noninvasive
Fungal Sinusitis
Invasive Presence of fungal hyphae within the
mucosa, submucosa, bone, or blood vessels of the paranasal sinuses
Noninvasive Absence of fungal hyphae within the
mucosa and other structures of the paranasal sinuses
Fungal Sinusitis - Classification Invasive
Acute Invasive Fungal Sinusitis Chronic Invasive Fungal Sinusitis Chronic Granulomatous Invasive Fungal
SinusitisNoninvasive
Allergic Fungal Sinusitis Fungus Ball (fungus mycetoma)
Fungus Ball
Older individuals, female>male ImmunocompetentMay have a history of trauma or
injury to sinusAsymptomatic or minimal symptoms
with chronic pressure or nasal discharge
Cacosmia (perception of foul odor when no such odor exists)
fumigatus and dematiaceous fungi most commonly cause fungal ball
Fungus Ball Mass within the lumen of paranasal sinus
and is usually limited to one sinus peanut-butter like appearance Frontal/Maxillary sinus most common
followed by sphenoid sinus Noncontrast CT – hyperattenuating mass
often with punctate calcifications MRI – variable T1 and hypointense T2 due
to absence of free water, calcifications and paramagnetic metals also generate decreased T2 signal – no central enhancement to differentiate from neoplasm
Noncontrast CT – hyperattenuating mass often with calcifications
MRI – variable T1 and hypointense T2 due to absence of free water, calcifications and paramagnetic metals also generate decreased T2 signal – no central enhancement to differentiate from neoplasm
Fungus Ball - CT
High density material with thickened walls of the maxillary sinus due to chronic inflammation
Fungus Ball Treatment
Surgical Removal with restoration of drainage of the sinus
Antifungal medications usually unnecessary
Recurrence is rare
Allergic Fungal Sinusitis Most common form of fungal sinusitis Common in warm, humid climates Hypersensitivity reaction to inhaled fungal
organisms resulting in chronic noninfectious inflammatory reaction - IgE type I immediate hypersensitivity and type III hypersensitivity are involved
Common organisms implicated – Bipolaris, Curvularia, Alternaria, Aspergillus, and Fusarium
“Allergic mucin” within affected sinus which is inspissated mucous the consistency of peanut butter with eosinophils on histology
Allergic Fungal Sinusitis - ClinicalYounger individuals, third decade,
immunocompetentOften associated history of atopy
with allergic rhinitis or asthmaChronic headaches, nasal
congestion, and chronic sinusitis for years
Allergic Fungal Sinusitis - Imaging Usually bilateral with multiple sinuses
involved if not pansinus involement Often has a nasal component Noncontrast CT – high attenuation allergic
mucin within lumen of sinuses – can mimic a mucocele with expansion of the sinus
MRI – variable T1 appearance, low T2 signal (attributed to high concentration of iron, magnesium, and manganese concentrated by fungal organisms and also due to a high protein, low free water content of allergic mucin
Allergic Fungal Sinusitis - Imaging
Allergic Fungal Sinusitis - Imaging
Moderately high T1 signal, low T2 signal with expanded sinus can be seen in allergic fungal sinusitis, mucocele, or sinonasal polyposis
Allergic Fungal Sinusitis - TreatmentSurgical removal of allergic mucin
with restoration of normal sinus drainage is goal
Longterm use of topical nasal steroids helps suppress the immune response and minimize recurrence
? Low dose oral steriods/ ? Immune therapy
Topical or systemic antifungals are not indicated
Acute Invasive Fungal Sinusitis Most lethal form of fungal sinusitis –
mortality 50-80% Rare in immunocompetent patients Two clinical populations
Poorly controlled Diabetics – ususally caused by fungi of order Zymocycetes (Rhizopus, Rhizomucor, Absidia, and Mucor)
Immunocompromised with severe neutropenia (chemotheraphy patients, BMT, organ transplants, AIDS) – Aspergillus accounts for 80% of infection in this group
Acute Invasive Fungal Sinusitis - Clinical Necrotic nasal septum ulcer (eschar),
sinusitis, rapid orbital and intracranial spread resulting in death
Angioinvasion and hematogenous dissemination common
Present with fever, facial pain, nasal congestion, epistaxis progressing to proptosis, visual disturbance, headache, mental status changes, seizures as spread occurs
73% of patients with intracranial spread die
Acute Invasive Fungal Sinusitis - Imaging Noncontrast CT
Severe unilateral nasal cavity soft tissue thickening is most consistent (but nonspecific) early CT finding
Hypoattenuating mucosal thickening within lumen of paranasal sinus with rapid aggressive bone destruction of sinus walls occurs as disease progresses
Unilateral involvement of ethmoids, sphenoids
Intracranial extension can result in cavernous sinus thrombosis, carotid artery invasion, occlusion, or pseudoaneurysm
Acute Invasive Fungal Sinusitis - CT
Unilateral ethmoid involvement with bone destruction, intraorbital spread and proptosis
Acute Invasive Fungal Sinusitis - MRI
Aspergillus involving the sphenoid sinus with invasion of the left cavernous sinus, thrombosis, extension to the left sylvian fissure and infratemporal fossa with cerebral infarctions.
Acute Invasive Fungal Sinusitis - ImagingMRI – better for evaluating
intracranial and intraorbital extension Evaluate for inflammatory change in
orbital fat and extraocular muscles Obliteration of periantral fat is a subtle
sign of extension Leptomeningeal enhancement
progressing to cerebritis and abscess
Aspergillus in left maxillary sinus with extension anterior and posterior to the retroantral space. There is diffuse involvement of the muscles of mastication.
Acute Invasive Fungal Sinusitis - TreatmentAggressive surgical debridement and
systemic antifungal therapy High doses of Amphotericin B (1-1.5
mg/kg/d) are recommended. Oral Itraconazole (400 mg/d) can replace Amphotericin B once the acute stage has passed
Reversal of cause of immunosuppression if possible
Intracranial spread is most predictive of mortality
Chronic Invasive Fungal Sinusitis Inhaled fungal organisms deposited
in nasal passageways and paranasal sinuses
Progression over months to years with fungal organisms invading mucosa, submucosa, blood vessels, and bony walls
Organisms – Mucor, Rhizopus, Aspergillus, Bipolaris, and Candida
Chronic Invasive Fungal Sinusitis – Clinical FeaturesUsually immunocompetentHistory of chronic rhinosinusitisUsually persistent and recurrent
diseaseMaxillofacial soft tissue swelling,
orbital invasion with proptosis, cranial neuropathies, decreased vision, can invade cribiform plate causing headaches, seizures, decreased mental status
Chronic Invasive Fungal Sinusitis – Imaging Noncontrast CT – Hyperattenuating soft
tissue mass withing one or more of paranasal sinuses, bone involvement often gives mottled appearance with or without sclerosis May mimic malignancy with masslike
appearance and extension beyond sinus confines
MRI – decreased signal on T1, markedly decreased signal on T2 weighted images
Chronic Invasive Fungal Sinusitis
Chronic Invasive Fungal Sinusitis – TreatmentSurgical exenteneratin of affected
tissues and systemic antifungalAmphotericin B (2 g/d) is
recommended; this can be replaced by Ketoconazole or Itraconazole
Needs aggressive treatment
Chronic Granulomatous Invasive Fungal Sinusitis
Primarily found in Africa (Sudan) and Southeast Asia, only few case reports in US
ImmunocompetentCaused by Aspergillus flavusCharacterized by noncaseating
granulomas in the tissues
Chronic Granulomatous Invasive Fungal Sinusitis
Chronic indolent course similar to chronic invasive fungal sinusitis
Considered by some as same entity as chronic invasive fungal sinusitis
Imaging characertistics are similar to those of chronic invasive fungal sinusitis
Often resembles a mass/neoplasms
Treatment is surgical debridement and systemic antifungals
Anti fungal treatment side effects Amphotericin B Acute renal failure, anemia,
agranulocytosis, acute liver failure, cardiopulmonary hypertension, and hemorrhagic gastroenteritis.
Itraconazole and fluconazole Drug-induced cardiac
dysrhythmias, hepatic dysfunction, urticaria, and anaphylaxis.
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