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Hegazy et al. Vessel Plus 2021;5:46 https://dx.doi.org/10.20517/2574-1209.2021.52 Page 3 of 8

- Otitis media and hearing loss: the middle ear cleft and the mastoid process are the most common sites
involved with GPA within the temporal bone. All kinds of hearing loss can result from GPA. Involvement
of the Eustachian tube can result in otitis media with effusion leading to conductive hearing loss. This may
further predispose to serous otitis media, chronic suppurative otitis media with persistently draining ears,
and worsening of hearing loss. The granulomas may present as a mass within the middle ear cavity.
Extension of involvement to the inner ear structures can lead to sensorineural hearing loss or mixed hearing
loss if combined with conductive hearing loss. Vestibular dysfunction may also result from inner ear
affection.

- Lower motor neuron paralysis of the facial nerve may occur if the necrotizing vasculitis involves the neural
vasa vasorum.

Investigations
ENT clinical evaluation using nasal endoscopic assessment can reveal the presence of nasal mucosal
crusting, beading, granulation tissue, ulceration, septal perforation (especially posterior), mucosal
hyperemia, friability, bloody rhinorrhea, and sinusitis [Figure 1]. Otological assessment using pure tone
audiometry, tympanometry, and acoustic reflex testing to evaluate possible sensorineural hearing loss or
conductive hearing loss may also be warranted. Involvement of the inner ear may indicate video
nystagmography. Pharyngolaryngoscopy is deemed necessary to evaluate for mucosal lesions, allow for
biopsy of suspicious masses, determine the presence of airway narrowing and assess the vocal fold mobility.
In case of pharyngeal involvement, functional endoscopic evaluation of swallowing can be performed to
assess the swallowing ability .
[1]

Laboratory investigations
Up to 90% of patients with generalized GPA have a positive ANCA . Up to 80%-90% of patients with GPA
[18]
are likely to have C-ANCA directed against proteinase 3 protein in the cytoplasm . However, only 60% of
[19]
patients with limited GPA, defined as GPA disease isolated to upper or lower respiratory tract with no renal
[4]
[20]
involvement , have a positive ANCA test . There is growing evidence that ANCA plays a major role in the
pathogenesis of GPA. ANCA antibodies play a role in the attachment of neutrophils to the vascular
endothelium early in the pathogenesis of the disease . Non-specific laboratory tests include complete
[21]
blood count which may show leukocytosis, eosinophilia, and thrombocytosis, and inflammatory markers
such as sedimentation rate and C-reactive protein which can be elevated. Laboratory tests may also show
[22]
involvement of other organs such as impaired kidney function and abnormal urine analysis .
Radiology
Computerized tomography (CT) of the paranasal sinuses may reveal mucosal thickening, nasal septal
destruction, sino-nasal mass with or without orbital involvement [Figure 2]. Bony destruction with resultant
osteo-neogenesis is not uncommon. Tracheal stenosis can be seen with GPA. CT scan of the neck is
mandatory to determine airway narrowing and aid the surgical planning. Chest x-ray may detect associated
lung involvement and further CT chest may be requested [17,23-25] . If upper airway obstruction is suspected,
pulmonary function test may be of a value. Flow volume loops may show characteristic inspiratory and
expiratory flattening [26,27] .

Pathology
Although biopsy from upper aerodigestive involved sites is easily accessible, it remains unreliable to make
the diagnosis. In one retrospective study, which included 126 patients who were clinically diagnosed with
GPA, biopsies taken from the nose, paranasal sinuses, larynx, mouth, periorbital tissue, mastoid, and middle
ear were reviewed to assess GPA pathology findings in these sites. All three findings typical for GPA