I found this interesting webpage:
http://en.wikivet.net/Avian_Sinusitis
Introduction
Sinus infection can occur in any
psittacine but is particularly common in imported grey parrots. It was largely thought to be associated with a diet deficient in
Vitamin A however there is now some controversy surrounding its contribution to the disease
[1] [2].
Signalment
Hypovitaminosis A is a nutritional deficiency thought to predispose birds to sinusitis
[1]. This can occur if the bird is fed and
all seed diet, which is
deficient in
vitamin A,
iodine and
calcium, therefore it is essential that a full dietary history is taken. Vitamin A deficiency causes some cells to differentiate abnormally. This occurs in the sinus, where the epithelial lining degenerates into
squamous metaplasia. This causes the
mucus to thicken, thus preventing debris from being flushed out of the sinus. This results in a
build-up of debris and bacteria, eventually resulting in infection
[3]. This deficiency can also contribute to the development of and
rhinoliths,
abscesses and
conjunctivitis. Currently it is thought that sinusitis may not occur as a result of vitamin A deficiency as many parrot diets now have an excess of Vitamin A
[2].
Clinical Signs
Early clinical signs include
sneezing,
proptosis and
clicking. Later,
swelling may develop around the
eyes or between the eyes and beak over the frontal signs. Excessive secretion of serous or mucous material from the respiratory mucous membranes is often reported. It is common for the bird to be suffering from concurrent disease such as pneumonia and
air sacculitis. Respiratory distress may be evident, however this should be observed in a quiet stress-free environment for reliable interpretation. Clinical exam is often better performed under general anaesthesia as the choana should be examined for any spread of infection.
Diagnosis
Clinical signs coupled with the history of a vitamin A deficient diet should be suggestive of sinusitis, however
needle biopsy of the swellings is required to make a
definitive diagnosis, as it allows for the differentiation from abscesses.
Cytology,
culture and sensitivity should be performed on the aspirated material to determine the presence and nature of infection. The most common infectious organisms are
Pseudomonas and
Mycoplasma species.
Radiography of the skull can also be performed to confirm the presence of sinusitis.
Treatment
Ideally the bird should be treated with the
antibiotic 'Baytril' (enrofloxacin) as it covers the above-mentioned bacteria. Additionally the bird should receive a dose of
Vitamin A by
intramuscular injection. Subsequent dietary supplementation of Vitamin A by feeding
orange and
dark green vegetables is necessary to prevent recurrence of infection
[3] [1]. Drainage and flushing of the sinus with antibiotics in severe cases is recommended by some
[2] but due to the anatomy of the sinuses and the nature of the inspissated pus produced, others report that it is normally unsuccessful
[1]. If rhinoliths or choanal abcesses are present they should be removed using a needle or dental instruments.
Prognosis
If the dietary deficiencies are addressed long term then infection is unlikely to recur. Therefore, if the bird recovers well from the original episode of sinusitis the prognosis is
good.
References
- ↑ 1.0 1.1 1.2 1.3 Lawton, M (1999) Management of respiratory disease in psittacine birds In Practice 1999 21: 76-8
- ↑ 2.0 2.1 2.2 Stanford, M (2009) Respiratory Disease in Birds Royal Veterinary College Integrated Course RVC
- ↑ 3.0 3.1 Forbes NA & Altman RB (1998) Self-Assessment Colour Review Avian Medicine Manson Publishing Ltd
