You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Keratoconjunctivitis sicca (also called "dry eye" or canine KCS) is a frequent clinical sign in dogs and cats. Sometimes it can be a sign associated with multiple endocrine disorders.

Keratoconjunctivitis sicca ("dry eye") is a condition in which there is reduced tear secretion, and it is confirmed by less than 5mm wetting at 60 seconds on the Schirmer Test. Some authors recommend less than 15mm wetting at 60 seconds as being suggestive of the disease.  There are several causes of the disease including :

• Primary, breed-related disease - thought to be due to damage to the secretory cells by autoimmune antibodies
• Canine distemper virus infection
• Iatrogenic - following the administration of sulphur-containing antibiotics
• Iatrogenic following the administration of H₂ receptor antagonist drugs
• Chronic conjunctivitis
• Trauma
• Neurogenic causes
• Aplasia or hypoplasia of the lachrymal gland 

Canine KCS has been reported to occur in association with multiple disorders due to autoimmune polyglandular syndromes in dogs. 

In humans autoimmune polyendocrinopathy syndromes may involve :

• Keratoconjunctivitis sicca
• Insulin-dependant diabetes mellitus
• Hypoadrenocorticism (Addison's disease)
• Graves Disease
• Chronic lymphocytic thyroiditis
• Gonadal failure

In dogs hypothyroidism and hypoadrenocorticism are the commonest manifestation of polyendocrinopathy, and diabetes mellitus with hypoparathyroidism also occurs. KCS has been reported to occur in association with the hypothyroidism and hypoadrenocorticism syndrome.

The possibility of multiple disorders occurring simultaneously  is one reason why a full screen should be performed in dogs with multiple clinical signs involving more than one organ system.

Updated January 2016