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Laryngeal disease in 69 cats: a retrospective
multicentre study
AL Lam*a, JA Beattyb, L Moorec, DJ Fostera, P Braina, R Churcherd, J Anglese, RW Lamf, VR Barrsb
*Corresponding author
aSmall Animal Specialist Hospital, North Ryde, New South Wales 2113, Australia; drames@gmail.com
bVal en tin e Char lt on Ca t Ce nt re, Fac ul ty of Vet eri nar y Scien ce, The Univ ersi ty of Sy dney, N ew Sou th Wal es 20 06 , Au st ral ia
c4 Paws Neutral Bay Veterinary Clinic, 154 Military Road, Neutral Bay, New South Wales 2089, Australia
dNorth Shore Veterinary Specialists, Achison Street, Crows Nest, New South Wales 2065, Australia
eAnimal Referral Hospital, Homebush, New South Wales 2140, Australia
fThe Royal Veterinary Col lege, North Mymms, Hertfordshire, AL9 7TA, Uni ted K ing dom
ABSTRACT
In cats with upper respiratory disease, localisation to the larynx can often be based on the history and physical examination
findings. This study was undertaken to identify the aetiology of laryngeal disease in cats presented to clinics in the Sydney
area and collate the signalment, clinical findings, diagnostic results, treatment and outcome. A second objective was to
examine whether noninvasive diagnostic techniques were sufficient to determine a diagnoses or whether invasive techniques
were required, and what morbidity this posed. Laryngeal paralysis and neoplasia were most frequent in this case series,
accounting for 75% of cases. Inflammatory disease was the next most frequent. Burmese cats were the most frequent
breed with laryngeal inflammation. The outcome for cats with laryngeal disease was dependent upon the aetiology.
Cats with acute laryngitis generally recovered. Cats with laryngeal paralysis often had extended survival times with
treatment. Cats with laryngeal carcinoma had the worst outcome. Non-invasive diagnostic techniques such as radiography,
ultrasonography and computed tomography were not helpful in identifying the aetiology of laryngeal disease. Diagnostic
procedures for laryngeal disease that required general anaesthesia such as laryngoscopy, fine needle aspiration and biopsy
were required to make a diagnosis. These techniques were not associated with deterioration of the cats’ condition and are
not contraindicated in cats with subacute or chronic disease. Aust Vet Pract 2012;42(4):321-326
INTRODUCTION
The most prominent clinical signs of laryngeal disease in cats
include stridor, dyspnoea and dysphonia.1,2 Stridor and dyspnoea
are typically inspiratory unless there is a fixed laryngeal obstruction,
such as a large mass. Fixed laryngeal obstruction would cause both
inspiratory and expiratory signs. Other clinical signs of laryngeal
disease include coughing and gagging, either due to laryngeal
stimulation or aspiration pneumonia. Non-specific clinical signs
such as weight loss are also observed. Weakness and exercise
intolerance, frequently observed in dogs with laryngeal disease, are
less obvious in cats because of their sedentary behaviour.3
The aetiologies of laryngeal disease in cats can be categorised as
paralysis, neoplasia, inflammation or other (trauma, cyst, polyp,
dysplasia and abscess) (Table 1).1,2,4-14 While historical and physical
examination findings are usually sufficient to localise disease to the
larynx, they rarely indicate the underlying aetiology. An exception
is when signs consistent with laryngeal paralysis are identified in
cats with a polyneuropathy. In most cats with signs of laryngeal
disease, determination of the underlying aetiology requires general
anaesthesia for laryngeal examination and tissue biopsy.
The prevalence of laryngeal diseases is not clear, in part due to
regional variation. 2,13 The aim of this multicentre, retrospective
study was to report the aetiology of laryngeal disease in cats from
the Sydney region. The signalment, clinical findings, diagnostic
investigation, treatments and outcomes were compared across
aetiology categories to identify differences that may assist with
clinical decision-making. We specifically examined whether
noninvasive diagnostic techniques were sufficient to determine a
diagnoses or whether invasive techniques were required, and what
morbidity this posed.
MATERIALS AND METHODS
Records of cats with laryngeal disease presenting between January
2001 and July 2010 at four specialist and emergency hospitals were
identified. Keywords included for identification of the records
was laryngeal, larynx, paralysis, laryngitis, neoplasia, carcinoma,
or lymphoma. Cases were included if a structural or functional
abnormality was identified on direct laryngeal examination.
Laryngeal examinations were performed under a plane of
anaesthesia that allowed spontaneous ventilation, except in cases
of tick paralysis. In cats with tick paralysis, the cat was conscious
or sedated and laryngeal examination was performed immediately
prior to intubation to secure the airway. A diagnosis of tick paralysis
was made when an engorged Ixodes spp. tick was found attached to
the cat and clinical signs were consistent with the diagnosis.19,20 Cats
with laryngeal masses were only included if a histologic or cytologic
diagnosis was available. Of 95 cases identified in the keyword
search, 18 were excluded because an upper airway examination was
not performed. Most of these cases that were excluded had an acute
Australian Veterinary Practitioner 42(4) December 2012 321
ORIGINAL STUDY
Tab le 1. Categorisation of the aetiology of cats reported with
laryngeal disease (1979-2011).
Aetiology Reference Number
of cats
Neoplasia Bertolani13 2011
Taylor2 2009
Taylor15 2009
Guentheryenke16 2007
Jakubiak8 2005
Carlisle7 1991
9
16
10
9
15
21
Paralysis /
paresis
Bertolani13 2011
Hardie1 2009
Taylor2 2009
Holland17 2008
Guentheryenke16 2007
Schachter5 2000
Schaer4 1979
11
10
14
3
2
16
1
Inflammatory Bertolani13 2011
Taylor2 2009
Guentheryenke16 2007
Jakubiak8 2005
Costello10 2001
Malik11 1991
Tasker18 1999
20
6
4
3
5
1
1
Other Taylor2 2009
Guentheryenke (trauma)16 2007
Costello (hyperplasia)10 2001
Rudorf (cyst)14 1999
5
1
1
1
onset of upper airway signs after anaesthesia and were suspected
to have laryngeal spasm. A further eight cases that underwent
laryngeal examination were excluded due to incomplete records.
Cases were categorised according to aetiology including paralysis,
neoplasia, inflammatory disease or other. Cats with two diseases
were categorised according to the presumed primary disease. The
signalment, clinical signs, duration of signs (acute <24 hours,
subacute 24 hours–7 days, chronic >7 days) findings on upper airway
examination, results of cytologic and histologic examinations,
feline immunodeficiency virus (FIV) and feline leukaemia virus
(FeLV) serostatus, retrovirus vaccination status, results of imaging
(radiography, ultrasound or computed tomography), treatment
and outcome were recorded for each case.
Survival was calculated from the date of presentation to the date of
death or euthanasia recorded or recalled by the owner or referring
veterinarian. Cats were censored if they were alive at the end of
the follow-up period (30th June 2011). Cats were censored at last
follow-up if the outcome was not determined.
Tr el l i s s ca t t e r p l o t s w e r e c r e a te d i n R ( h t t p: / / w w w. r - pr o j e c t .
org/) and mosaic plots using the Mondrian package in R (http://
rosuda.org/mondrian/) to visually evaluate possible important
clinical variables associated with aetiology. Associations between
clinical findings and aetiology were further explored. Two-tailed
Fisher exact test and Chi Square analysis with Yates’ correction for
continuity was used to assess the differences in distribution of the
duration of clinical signs prior to presentation across aetiology,
and intercategory and intracategory distributions of clinical
variables. Age was compared across various groupings using a
Mann Whitney U test. Survival functions inlcuding right censored
observations were generated using Kaplan-Meier survival methods
and Log rank tests were used to determine differences in functions
stratified according to aetiology categorisation. Estimated median
survival times were obtained from the functions. Significance for
all tests was set at p<005. GraphPad InStat 3 Mac version 5.04
for Windows (GraphPad Software, La Jolla California USA, www.
graphpad.com) was used for the analysis.
RESULTS
Sixty-nine cases were included (Table 2). There were 29 neutered
males, one entire male, 38 neutered females and one entire female.
The mean age was 10 years 2 months (median 11 years, range 9
months-19 years). There were 37 mixed bred and 32 pure bred cats.
Categorisation according to aetiology showed paralysis (n=29),
neoplasia (n=24), inflammatory (n=14) and other (n=2). Cats with
neoplasia (mean age 12 years 7 months, median 12 years, range
6 years 9 months–18 years) were significantly older than with
inflammatory disease (mean age 7 years 10 months, median 7 years,
range 9 months–18 years) (P=0.005, Mann Whitney U test). There
was no difference in survival across categories (P=0.062, Log Rank
test).
The most frequently recorded clinical signs at presentation were
stridor (n=57), weight loss (n= 25) and dysphonia (n=21). Other
clinical findings included a history of inappetence or dysphagia
(n=19), and dyspnoea (n=19) and an attached tick (n=4) at
presentation (Table 3). There was no association between clinical
sign and categorisation, however, the presence of a tick was
significantly associated with a diagnosis of laryngeal paralysis
(P=0.023, Chi Square). Two cats had generalised laryngeal oedema
that was considered secondary to laryngeal paralysis. These cases
were categorised as paralysis. One cat with concurrent laryngeal
carcinoma and paralysis was categorised as neoplasia.
Upper cervical radiographs were taken in 22 cats (paralysis n=11,
neoplasia n=11) and reported as normal in 21 cats. A laryngeal
soft tissue density was identified in one cat and later identified
as squamous cell carcinoma. Thoracic radiographs were taken in
10 cats and reported consistent with pneumonia (n=2; paralysis,
inflammation), pneumomediastinum (n=2; paralysis, neoplasia-
laryngeal carcinoma) and a pulmonary mass (n=1; neoplasia-
laryngeal carcinoma). Pleural effusion was noted in one cat with
laryngeal paralysis. This case was diagnosed with congestive heart
failure due to restrictive cardiomyopathy.
Echolaryngography was performed in two cats and showed
unilateral paralysis in one cat and a laryngeal mass in one cat.
Computed tomography of the cervical region (n=3) did not show
abnormalities in two cases of paralysis but reported signs consistent
with an invasive thyroid mass in one cat.
An acute presentation was more frequent with inflammatory and
other aetiologies and a subacute or chronic presentation was more
frequent in cases categorised as paralysis or neoplasia (Table 4).
Serology for FIV was positive in three of eight cats (2 neoplasia–
lymphoma, 1 paralysis). None of the 69 cats were vaccinated against
FIV. Serology for FeLV was negative for seven of seven cats tested.
322 Australian Veterinary Practitioner 42(4) December 2012
ORIGINAL STUDY
Australian Veterinary Practitioner 42(4) December 2012 323
ORIGINAL STUDY
Table 2. Frequency and summary of clinical findings according to aetiology of laryngeal disease in 69 cats
Diagnosis n Age
mean (median)a
Age range Breedb (n) Biopsy /FNA (n) Tr e a t m e n t c (n) Survival by treatment
range in days
Survival mean
(median) in days
Survival
range in daysd
Alive @
foll ow up (n )
Laryngeal
paralysis
29 9y9m
(10y)
1y-19y DSH(14) Aby(3)
Burm(2) Siam(2)
Per( 1) BSH(2)
Manx(2)Exotic(1)
87 (7) 0-1295 15
Non-tick 25 10y11m
(10y10m)
2y-19y Lateralisation (4)
Medical (21)
0-1295
0-400*
175 (418)
39 (7)
0-1295 1
12
Tick 4 2y9m
(2y6m)
1y-5y Ven til ati on (3)
Te m p . t r a c h e o s t o m y ( 1 )
General anaesthesia (1)
Tick antiserum ( 4)
3-21*
3
7*
9 (6) 3-21* 2
Neoplasia 24 12y7m
(12y0m)
6y9my-18y 14/7 61(18) 0-300* 0
Squamous cell
carcinoma
9 11y10m
(11y)
6y9m-18y DSH(4) Siam(1) BSH(1)
Aby(1) DLH(1) Pers(1)
5/4 Steroids (2) 40, 52 10(0) 0-52 0
Other
carcinomas
3 15y
(16y4m)
12y-16y8m DSH(3) 2/0 Surgery (2)
Radiotherapy (1)
7, 28
240
92(28) 7-240 0
Lymphoma 12 13y4m
(13y2m)
8y-18y DSH(9) Burm(1)
DLH(1) Pers(1)
7/3 COP (3)
MW25 (4)
Depomedrol (1)
Te m p . t r a c h e o s t o m y ( 1 )
103-300*
30-175*
90
107(83) 0—300* 2
1
0
0
Inflammatory 14 7y8m
(7y)
9m-18y DSH(4) DLH(1)
Burm(7) Siam(1)
Manx(1)
4/2
0/1
Steroids (8)
Antibiotics (7)
Ven til ati on (1)
91(35)
5*
10*
0-720*
5*
10*
9
Other
(spasm)
21y
4y
1y-4y DSH(1)
DLH(1)
Steroids (1)
Antibiotics (1)
Intubation (2)
2
Overall 69 10y2m
(11y0m)
9m-19y 18/11 77 (10) 0-1295 29
ay = years, m = months; b DSH = Domestic shorthair, DLH = domestic shorthair, Burm = Burmese, Siam = Siamese, Aby = Abyssinian, Per = Persian, BSH = British short hair, cCOP = cyclosphosphamide,
vincristine, prednisolone, MW25 = granulocyte colony-stimulating factor 25 kDa molecular weight, d*right censored observation
324 Australian Veterinary Practitioner 42(4) December 2012
Table 3. Frequency of clinical signs at presentation for 69 cats
with laryngeal disease
Clinical signs n
Stridor or wheeze 57
Weight loss 25
Dysphonia 21
Inappetence or dysphagia 19
Dyspnoea 19
Engorged tick attached 4
Table 4. Frequency of categories of duration of clinical signs
prior to presentation according to aetiology of laryngeal
disease in 69 cats
Aetiology Acute
<24
hours
Subacute
>24 hours
-7 days
Chronic
>7 days
Total
Paralysis 5 14 10 29
Neoplasia -
carcinoma
2 4 6 12
Neoplasia -
lymphoma
0 7 5 12
Inflammatory 4 2 6 12
Other 2 2 0 4
Tw en t y n i n e c a s e s w er e c a t e go r i s e d a s p a r a l y s is ( b i l a te r a l = 1 9 ;
unilateral=10, left=6, right=4) (Table 2). No cases were recorded
with laryngeal paresis. Cats with laryngeal paralysis had a mean
age of 9 years 9 months (median 10 years, range 1-19 years). All
cases of laryngeal paralysis were investigated and underlying
disease was identified in 12, including tick paralysis (n=4),
idiopathic polyneuropathy (n=3), bronchogenic carcinoma
(n=1), brainstem lesion (n=2) and trauma (n=2). The remaining
17 cats were diagnosed with idiopathic laryngeal paralysis. Cats
with tick paralysis (mean age 2 years 9 months, median 2 years
6 months, range 1-5 years) were significantly younger than cats
with laryngeal paralysis due to other causes (mean age 10 years 11
months, median 10 years 10 months, range 2-19 years) (P=0.005,
Mann Whitney U test). Thoracic radiography was performed in
four cats with laryngeal paralysis and findings were consistent with
bronchopneumonia (n=1), pneumomediastinum (n=1), pleural
effusion (n=1) and normal (n=1). Computed tomography of the
cervical region was performed in two cats with laryngeal paralysis
but was considered normal. All cats with tick paralysis were treated
with tick anti-serum and three cats received ventilation. Two cats
were alive at follow-up (seven days, 21 days after diagnosis), one
cats died at four days and the other was euthanised after three days
of ventilation. Four cats had unilateral arytenoid lateralisation,
four cats had a temporary tracheostomy and one cats underwent
laryngeal sacculectomy. Of the four cats undergoing arytenoid
lateralisation, two cats were euthanised at one and 201 days after
surgery because of severe pneumonia, one cat was lost to follow-up
at 175 days and one cat was euthanised for an unrelated problem
at 1295 days. For cats receiving a temporary tracheostomy, three
died by three days due to progressive tick paralysis (n=1) or
bronchopneumonia (n=2). The remaining cat had a traumatic
aetiology and recovered.
Twenty four cats categorised as neoplasia included 21 cats with
primary laryngeal tumours (lymphoma n=12, squamous cell
carcinoma n=9), one cat with primary laryngotracheal tumour
(laryngo-tracheal carcinoma ), and two cats with extension
of regional neoplasia (thyroid carcinomas) (Table 5). All cats
with neoplasia had a mass noted on oral examination (Table 2).
Presentation was typically subacute or chronic although two cats
presented acutely (Table 4). A cytologic diagnosis was made in four
cats and a histologic diagnosis was made in eight cats. There was
a discrepancy between cytologic (adenocarcinoma) and histologic
(squamous cell carcinoma) diagnoses in one cat, which was finally
diagnosed as laryngotracheal squamous cell carcinoma. Two cats
with primary squamous cell carcinoma had concurrent pulmonary
metastases. Eleven cats with neoplasia were euthanised at the time
of diagnosis (squamous cell carcinoma n=7, lymphoma n=4).
Two cats with primary squamous cell carcinoma treated with
prednisolone (0.5 mg/kg PO once daily) survived for 40 and 52
days. One cat with invasive thyroid carcinoma was palliated with
surgical debridement (survival 28 days) and one cat was treated
with radioiodine I131 (in remission when euthanised because of
progression of chronic kidney disease 240 days after diagnosis).
The cat with laryngotracheal carcinoma was treated with piroxicam
1 mg PO once daily for seven days but did not respond and was
euthanised (Table 2). Survival for cats with carcinoma ranged from
0-240 days (estimated median 7 days) (Table 2).
Cats with lymphoma ranged from in age from 8-18 years (mean
13 years 4 months, median 13 years 2 months) (Table 2). Four
cats with lymphoma were euthanised at diagnosis. Seven cats with
lymphoma treated with chemotherapy survived from 30 days to at
least 300 days after diagnosis (estimated median 150 days) (Table
2).
Cats with inflammatory disease ranged in age from 9 months to
18 years (mean 7 years 8 months, median 7 years). The duration
of their clinical signs was variable (Table 4). Burmese cats (7/14)
were more frequent than all other breeds combined (P<0.001,
Fisher Exact Test; Table 2). Diagnosis was based on cytology (n=2),
histology (n=4) or direct visualisation (n=6) of diffuse, bilateral,
laryngeal oedema with rapid resolution of signs after supportive
treatment (doxycycline 5 mg/kg PO twice daily for 3-6 weeks,
n=4, and or prednisolone 0.5-1 mg/kg PO once daily, n=8). One
cat was euthanised at the time of diagnosis. For the Burmese cats,
concurrent disease included upper respiratory tract infection
(n=2), head trauma (n=1), feline infectious peritonitis (n=1),
bronchitis (n=1) and unknown (n=2). For the remaining cats,
concurrent disease included chronic kidney disease (n=2), upper
ORIGINAL STUDY
Australian Veterinary Practitioner 42(4) December 2012 325
ORIGINAL STUDY
respiratory tract infection (n=2), bronchitis (n=1), pancreatitis
(n=1) and string foreign body (n=1).
Cats categorised as other included two cats with acute laryngeal
spasm, both of which resolved within 24 hours. One cat had just
been extubated and the other cat had permethrin toxicity. Both
were temporarily intubated but recovered without complication.
DISCUSSION
Paralysis and neoplasia, comprising 77% of all cases, were the most
frequent categories of laryngeal disease in this cohort of 69 cats.
This is similar to the findings of a retrospective study of 35 cats
from the United Kingdom where paralysis and neoplasia accounted
for 60% of the cases.2 in comparison, a study of 40 cats with
laryngeal disease from France had 50% of cats with inflammatory
disease.2,13 Since these are case-based studies, differences may be the
result of sampling bias and sample size, or regional variations and
underlying disease prevalence. For example, in our study, paralysis
due to Ixodes holocyclus is a regional variant.20,21 Tick paralysis is
reported as a cause of laryngeal paralysis in cats in our region but is
extremely rare in Europe.20
The paradigm that diagnostics should proceed from non-invasive
procedures with perceived low morbidity to invasive techniques
with perceived high morbidity is pertinent for the investigation of
laryngeal disorders. The perceived morbidity associated with general
anaesthesia and biopsy in an animal with airway compromise and
in some cases, concurrent intrathoracic disease, emphasises the
importance of maximising the diagnostic yield of non-invasive
procedures. However, only the presence of an engorged tick was
useful in ranking differentials. Dyspnoea and stridor were the
most common presenting signs but were not associated with any
particular disease category. Dysphonia was not present in all cats
with laryngeal disease, reported in only 21/69 (30%) of our cases,
and 51% of 35 cats in a previous study.2 Complete blood count,
serum biochemistry and urinalysis were infrequently performed
and not assessed. They were less likely to be performed since the
diagnostic yield of these tests is low in dyspnoeic cats and must
be balanced against the risk of respiratory decompensation whilst
obtaining samples.22 Radiography of the larynx was insensitive
in defining masses of the upper airway, with only one of 22 cases
reported abnormal in our study. Other reports have suggested that
soft tissue opacities are detected in most cases of neoplasia and
inflammation.2,9,10 Radiographs were not consistently reviewed by
a board-certified radiologist in our study which may have reduced
the sensitivity of this modality in identifying upper airway masses.
Radiography was useful in identifying concurrent intrathoracic
disease. Aspiration pneumonia or bronchopneumonia occurred
in cats with laryngeal paralysis but was not seen with any other
disease. No concurrent thoracic abnormalities were identified in
radiographs of cats with inflammatory laryngeal disease. Evidence
of metastasis was not observed in any thoracic radiograph.
Thoracic radiographs therefore may be a good screening modality
for detection of pulmonary disease, such as aspiration pneumonia,
prior to planned anaesthesia for airway examination.
Echolaryngography performed in two cats in this study and is
a non-invasive modality to investigate laryngeal structure and
function in conscious, minimally-restrained cats. With skilled
operation, an excellent association between echolaryngography
findings and those of direct laryngoscopy has been demonstrated in
cats.2,23 However, echolaryngography was less sensitive than direct
visualisation in dogs.24 Echolaryngography should be considered
an adjunct to direct laryngoscopy and improve planning prior to
further interventions. It was underutilitised in cats of our study.
Tick paralysis was identified as the cause of laryngeal disease in 4 of
29 cats. This likely represents a biased indicator of the prevalence of
tick paralysis since laryngeal examination was an inclusion criterion
for this study and is only performed in cats with severe disease or
those which require intubation. Also, the absence of an attached
tick at the time of diagnosis does not eliminate this tick paralysis
as a cause. A recent travel history and thorough examination for an
attached tick or skin lesion left by a tick are recommended for cats
presenting with signs of general muscle weakness. Only two of four
cats with tick paralysis in this study survived to discharge but this
reflects a subset of severely affected cases that required intubation
(and thus laryngeal examination). The overall prognosis for cats
with tick intoxication in Australia is good with mortality reported
in less than 1% of cases.19,20
Lymphoma was the most freqeunt primary neoplasia of the larynx
in cats of our study, with squamous cell carcinoma the next most
frequent. This reflects prevalence described in the literature.2,6-8
Tw o c a t s h a d e x t e n si o n o f t h y r oi d c a r ci n o m a a f f e c t in g t h e l a r y n x .
Local extension to the lumen of the larynx has been reported in
people with thyroid carcinoma.25 The cats with thyroid carcinoma
in our study presented because of laryngeal, rather than thyroid,
dysfunction. Gross involvement of the larynx with neoplasia
was variable but often appeared bilateral. One study found that
the majority of laryngeal masses in cats (14/19) were unilateral
although tis included neoplastic, non-neoplastic (inflammatory
and hyperplastic) masses.8 A study of three cats with inflammatory
disease of the larynx showed gross unilateral disease in two cats and
bilateral involvement in one cat.9 The presence of gross unilateral
or bilateral disease does not appear distinguish between neoplasia
and inflammation.
Biopsy for structural laryngeal lesions was not consistently
performed in cats in our study. Aspiration of the larynx offers a
minimally invasive option with minimal morbidity. Cytology
can be interpreted rapidly and is often sufficient for diagnosis.
However, histologic examination of carefully performed tissue
biopsies should also be performed, as this was not associated
with any additional morbidity and will provide a more accurate
diagnosis. All cats were treated with corticosteroids prior to
laryngeal biopsy and one of the 18 cats had exacerbation of airway
obstruction after biopsy, a similar experience to a previous study.2
In contrast, a case series of cats undergoing tracheostomy reported
four of five cats with laryngeal inflammation required temporary
tracheostomy after biopsy despite treatment with corticosteroids.10
Administration of a short-acting corticosteroid prior to biopsy may
be reduce morbidity.
If cytology is consistent with lymphoma, immediate treatment with
chemotherapy could be considered whilst the results of histologic
examination are pending. For other cytologic diagnoses, supportive
care should be recommended until histopathology results are
received.
We reported laryngeal inflammation in seven Burmese cats in our
Australian Veterinary Practitioner 42(4) December 2012
ORIGINAL STUDY
study. Acute laryngeal swelling in Burmese siblings from Europe has
been reported and congential laryngeal hypoplasia was proposed as
the cause.2 We saw no pattern in aetiology in the Burmese cats in
our study but studies to assess laryngeal conformation in Burmese
cats may reveal an underlying problem.
We found no association between aetiology category and outcome
in our study and the type of diagnostic evaluation did not appear
to affect morbidity or outcome. Based on the evaluation of these
69 cats, diagnostic techniques such as biopsy should be performed
when indicated, as they provide important information necessary
for a diagnosis.
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