Keratoconjunctivitis Sicca - Revision history

Gd49 at 10:25, 21 February 2014

2014-02-21T10:25:40Z

Gd49 at 10:24, 21 February 2014

2014-02-21T10:24:08Z

Gd49: Created page with "'''Keratoconjunctivitis Sicca''' (KCS)is a condition resulting from the lack of production of the '''aqueous''' phase of the tear film. It is also known as '''dry eye'''. ==A..."

2014-02-20T17:43:07Z

Created page with "'''Keratoconjunctivitis Sicca''' (KCS)is a condition resulting from the lack of production of the '''aqueous''' phase of the tear film. It is also known as '''dry eye'''. ==A..."

New page

'''Keratoconjunctivitis Sicca''' (KCS)is a condition resulting from the lack of production of the '''aqueous''' phase of the tear film. It is also known as '''dry eye'''.

==Aetiology==

===Immune-Mediated===

The most common cause in '''dogs'''. The immune system damages the glandular tissue. Dogs with KCS often have other '''immune-mediated''' diseases.

===Iatrogenic===

Certain '''drugs''', including [[Sulphonamides]], have been associated with KCS. '''Atropine''' causes a temporary reduction in tear production.

Surgical excision of the '''Nictating Gland''' has been associated with KCS later in life, with a '''median''' time for onset of signs 4.5 years after surgery.

===Neurogenic===

KCS occurs if '''parasympathetic''' innervation to the glands is disrupted. Possible causes include '''trauma''', '''neoplasia''', '''infection''' and '''surgical intervention'''. The KCS is more likely to be '''unilateral'''.

===Congenital===

Due to '''glandular aplasia''' or '''hypoplasia'''. More common in '''miniature''' breeds. May resolve with '''maturity'''.

===Infectious===

Infection with [[Canine Distemper Virus]] may result in temporary or permanent dysfunction of the glands. [[Leishmania]] can also cause KCS, as can any '''chronic''' infectious process that results in '''fibrosis''' of the glands.

==Signalment==

Dogs over '''10 years''' old are at greater risk of KCS due to '''senile atrophy''' of their glands. '''Boston Terriers''', '''Cavalier King Charles Spaniels''', '''English Bulldogs''', '''English Springer Spaniels''', '''Lhasa Apsos''', '''Minature Schnauzers''', '''Shih Tzus''', '''West Highland West Terriers''' and '''Yorkshire Terriers''' are all consider predisposed.

==Clinical Signs==

A '''thick mucoid and mucopurulent''' discharge is the most consistent sign of KCS. It often adheres to the '''eyelids'''. The '''conjunctiva''' may be '''thickened, hyperemic''' and '''chemotic'''.

'''Blepharospasm''' may occur to a variable degree. [[Corneal Ulceration - Dogs and Cats|Corneal ulceration]] often occurs, and may not heal as well as expected. '''Corneal Vascularisation''' and '''Pigmentation''' occur in chronic cases, leading to vision loss.

A '''dry, lusterless cornea''' is considered pathognomic for KCS, but only occurs in 25% of cases.

Clinical signs can wax and wane, and are often worse at certain times of the year, such as hot and dry periods or in winter when humidity is low.

==Diagnosis==

'''Schirmer Tear Tests''' are used to diagnose KCS. Normal values are in excess of 10mm. KCS should also be suspected when values are less than 15mm in conditions where excess tear production is expected, such as '''corneal ulceration'''.

Consideration should be given to ruling out other conditions that have been associated with KCS, including [[Hypothyroidism]], [[Diabetes Mellitus]] and '''Polyarthritis'''.

{{Unfinished}}

@@ Line 55: / Line 55: @@
 '''Cyclosporine''' is believed to help manage KCS by reducing immune-mediated destruction of the gland and by stimulating '''tear production''' by binding with '''prolactin receptors'''. Once treatment is started, tear production should be tested after a month. If there is a good response the dose may be tapered.
-====Tear Substitutes===
+====Tear Substitutes====
 A range of human tear substitute products may be used in dogs. Individuals react differently to different formulations so authors recommend trialling different preparations to see which gives the best clinical response.

← Older revision		Revision as of 10:24, 21 February 2014
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	Consideration should be given to ruling out other conditions that have been associated with KCS, including [[Hypothyroidism]], [[Diabetes Mellitus]] and '''Polyarthritis'''.		Consideration should be given to ruling out other conditions that have been associated with KCS, including [[Hypothyroidism]], [[Diabetes Mellitus]] and '''Polyarthritis'''.

−	~~{{Unfinished}}~~	+	==Treatment==
		+
		+	===Medical Therapy===
		+
		+	Medical therapy is normally used first for KCS, with surgical treatment only used if there is a poor response to medical therapy.
		+
		+	====Cyclosporine====
		+
		+	'''Cyclosporine''' is believed to help manage KCS by reducing immune-mediated destruction of the gland and by stimulating '''tear production''' by binding with '''prolactin receptors'''. Once treatment is started, tear production should be tested after a month. If there is a good response the dose may be tapered.
		+
		+	====Tear Substitutes===
		+
		+	A range of human tear substitute products may be used in dogs. Individuals react differently to different formulations so authors recommend trialling different preparations to see which gives the best clinical response.
		+
		+	====Pilocarpine====
		+
		+	May be more effective in '''neurogenic''' cases of KCS. Care must be taken to avoid systemic side effects.
		+
		+	===Surgery===
		+
		+	'''Parotid Duct Transposition''' may be performed in cases that respond poorly to medical treatment.
		+
		+	==Control==
		+
		+	KCS cases secondary to drug use, trauma or infection may resolve after '''45-60 days'''. Other causes normally require life long therapy.
		+
		+	==References==
		+
		+	Maggs, D et al (2007) '''Slatter's Fundamentals Of Veterinary Ophthalmology''' (Fourth Edition) ''Saunders''
		+
		+	Peiffer, Robert J, and Petersen-Jones, Simon M (2008) '''Small Animal Ophthalmology''' (Fourth Edition) ''Saunders''
		+
		+	[[Category:Corneal Diseases - Cat]]
		+	[[Category:Corneal Diseases - Dog]]