Cutaneous mucinosis

What is ... ?: 

In this condition there is a build-up of abnormal amounts of mucin (thick, clear, sticky fluid) under the skin. It occurs primarily in the Chinese shar pei which has more skin mucin than other breeds to begin with.

How is ... inherited?: 

unknown. There is probably a relationship between the increased mucin under the skin of the shar pei, and the pronounced skin folds of the breed.

What does ... mean to your dog & you?: 

Most often this condition is only cosmetic - that is, it will affect your dog's appearance but not his or her health. Shar peis with mucinosis have excessive skin folding and/or lumps and bumps (vesicles or pockets of mucin). Many dogs seem to outgrow the condition by  5 or so years of age.
Excessive mucinosis can interfere with breathing if the vesicles are in the back of the mouth. This may cause your dog to snort and snore, and can increase the risks associated with general anesthesia

How is ... diagnosed?: 

Your veterinarian will take a skin biopsy (a simple procedure, done with local anesthetic) for examination by a veterinary pathologist. With this condition, the biopsy will show excessive mucin in the layers of the skin.
Excessive mucinosis can also occur with hypothyroidism, a condition to which the Chinese shar pei is prone.

How is ... treated?: 

Dogs with breathing problems are treated with gradually tapering doses of corticosteroids over several weeks, to reduce the amount of mucin. Usually only 1 course of treatment is needed.
For the veterinarian: Treatment should be considered in dogs with oropharnygeal involvement, who may experience respiratory arrest under general anesthesia. If repeated treatment is required, hypothyroidism should be ruled out. 

For the veterinarian: 

The vesicles look similar to those seen in the various autoimmune disorders; however the content (mucin) is thick and sticky rather than serous.
Concurrent hypothyroidism may lead to severe mucinosis.

Breeding advice: 

It is preferable not to breed affected dogs or close relatives.


Scott, D.W., Miller, W.H., Griffin, C.E. 1995. Muller and Kirk's Small Animal Dermatology. p. 800.  W.B. Saunders Co., Toronto.

What breeds are affected by ... ?