ANCA vasculitis is a rare disease characterized by antibodies against
neutrophil and monocyte lysosomal enzymes which include myeloperoxidase
and proteinase 3 (1). The pathogenesis for ANCA vasculitis involves
numerous immune cells; B lymphocytes produce ANCA, with BAFF encouraging
the autoimmunity with B cells, plasma blasts and plasma cells (2). These
activate neutrophils and results in generation of C5a via the complete
pathway, causing further activation of neutrophils(3). Activated
neutrophils results in propagation of tissue damage and vascular
inflammation.
The main target organs in granulomatous polyangiitis include the ear,
nose throat and upper respiratory tract, glomerulonephritis of the
kidney and the lungs. Localized disease manifestation can include the
nose (rhinorrhea, nasal crusts, septal perforation) and ear (otitis
media, hearing loss, sensorineural deficits). The diagnosis of
vasculitis from localized disease manifestation can be difficult (1).
Otological manifestations as seen in our patient as otitis media is very
uncommon as an initial presentation. Granulomatosis polyangiitis can
affect the external, inner and middle ear. Otitis media is caused by
granulomatous process that occurs in the middle ear and can also involve
the mastoid cavity (4). In many cases it is difficult to differentiate
from otitis media and granulomatous polyangiitis. The otological
symptoms occur insidiously and making early diagnosis essential as one
has the risk of developing profound hearing loss and the systemic
disease can be fatal, hence early diagnosis has become paramount
importance to improve prognosis (5). The ontological symptoms tend to
progress despite myringotomy or mastoidectomy (1). The above patient had
undergone an mastoidectomy twice with progression of symptoms. Most
cases of otitis media associated vasculitis (OMAAV) present with facial
nerve palsy (6).
Neurological manifestations can occur but are rare in granulomatous
polyangiitis. They may present with cranial nerve palsy, peripheral
neuropathy cerebrovascular events or cerebritis (7). Three main
histological frameworks have been identified: CNS vasculitis of the
small vessels of the brain and spinal cord, granuloma invasion from
extracranial site, isolated intracranial granulation(8). The unusual
manifestation in the aforementioned patient was the presentation of
otitis media with trigeminal neuralgia and her disease progressed to
peripheral length dependent neuropathy and there after a pontine
infarct. Peripheral neuropathy is the most common neurological
manifestation as per De Groot K et la; he has a cohort of 128 patients
with GPA 46% of the patients had peripheral neuropathy and 4% had
cranial nerve palsies (9). The unusual presentation we had with our
patient is the presentation with chronic otitis media and trigeminal
neuralgia, most patient with otitis media tend to present with facial
never palsies as illustrated by Yasuaki Harabuchi et la facial nerve
palsy can be caused by inflammatory granulation that spread through the
facial canal, this is not uncommon with Otitis media associated ANCA
vasculitis (5). Cerebral Vascular accidents is also an uncommon
manifestation of GPA though can occur, De luna et al had 35 patients in
her cohort of study all of them underwent an MRI of the brain and 43 %
of patients had either ischemic or hemorrhagic change in the blood
vessels (8).
ANCA vasculitis has a high rate of mortality when not diagnosed
efficiently, the prevalence and incidence of ANCA vasculitis low in
Africa and this can be secondary to having low resource centers to carry
out tests for confirmation (10). It is important to treat as early once
the symptoms manifest though many patient that present with otitis media
miss the early window on treatment and fall in the curve of high
mortality rate. Treatment for ANCA vasculitis is induction of remission
via high dose steroids at 1mg/kg/day, where they normally pulse with
steroids for two to three days(2). Addition of cyclophosphamide tends to
improve the remission time in patient with ANCA vasculitis, rituximab
and plasma exchange are other possibilities for treatment as well (2).
Otological symptoms and CNS symptoms are rare complications but can
present as atypical symptoms as in our case, it is essential to identify
these cases early to prevent mortality rates as early treatment is the
key to survival and remission.
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