Pannus in German Shepherds - Page 3

same topic, but different thread........some of us were discussing the possibility that our dogs had inherited pannus from eiko kirschental.  not the only carrier, ofcourse, but worth taking into consideration and even more so if there are any plans of linebreeding.

pjp

I have had many GSDs in my custody whom I assure you had NO Eiko in their bloodlines. Pannus is a genetic problem,  and probably has been in many breeds for many generations.

Ooops I meant to say Cholesterol deposits...Here is a picture of a dog that has that...Skykat is this what your dog's eyes look like?

Just a thought, if your dog does not have pannus, ask about ehrlichiosis, a tick borne disease that can cause eye problems in it's chronic stage.....just a thought...jh

There are several conditions that can cause deposits in eye tissue, including cholesterol and mineral deposits. See an eye specialist if you are concerned. It does not sound like pannus.

Pannus

1. What is the agent or cause of the disease and how is it transmitted?

Pannus is an old term describing a membrane that covers the cornea as a result of long term corneal inflammation. More recently the syndrome is referred to as Chronic Superficial Keratitis (CSK); ie., long term inflammation of the cornea. Pannus has no known cause but certain risk factors, namely, ultraviolet light, altitude, and breed are thought to be involved. It is important to recognize that the cornea is very limited in its ability to respond to injury and this may play a role in the development of pannus.

In the past, discussions centered around infectious agents. Although the precise origins of the disease are still not known in detail, it is now generally accepted to be a derailment of the immune system whereby the organism, in an autoimmune response, produces antibodies or toxic immune cells against its own tissues. At the onset of the disease additional factors are involved: those naturally produced by the body (endogenic), and those which are external (exogenic). The endogenic factor in this context appears to be a breed-dependent inherited predisposition to this disease in the German Shepherd Dog. The predominant exogenic factor is ascribed to ultraviolet rays in sunlight as the trigger of pannus which explains the increased incidence of the disease during sunny months.

A related condition where a similar immune mediated reaction is confined to the conjunctiva and the third eyelid is called PLASMOMA or Plasmacytic Lymphocytic Conjunctivitis of the third eyelid. This variation is also much more common in the German Shepherd. Compared to Pannus, plasmoma is less threatening to the vision, may cause more discomfort, and is somewhat more resistant to the treatment regime which is the same as for Pannus

2. What are the symptoms or signs of the disease?

The cardinal sign is infiltration into the clear cornea, causing whitish, pink, or brown opacification. This invariably starts at the edge of the clear cornea and extends inward. The most common location is at the outer, lower corner of the eye.

Initially, redness and brown pigment may be seen in the mucous membrane just outside the edge of the cornea. Whitish infiltrates of inflammatory cells into the cornea ensues, followed by ingrowth of new blood vessels into the normally avascular cornea. Later, connective tissue grows in and finally this is pigmented brown.

In a small number of cases, two other symptoms may occur, simultaneously or one at a time. These are thickening, redness, and depigmentation of the third eyelid and chronic, erosive ulcers of the lower eyelid near the inner corner of the eye.

When acute or progressing, the disease is uncomfortable to the dog. When kept under adequate therapy, the disease normally does not cause irritation.

Signs of the disease include bilateral appearances of corneal pigment and small blood vessels spreading out over the cornea. Uncommonly, the pannus can erode the epithelium and alter the transparency of the stroma.

Pannus first appears in the outer regions of the cornea and, in almost all cases, affects both eyes simultaneously. Vascular granules and connective tissue establish themselves at the border between the sclera and the cornea,

which is often variously pigmented, and grow into the top-most layers of the cornea. This results in the formation of an opaque, cherry-coloured spot with an uneven surface often ringed by a fatty, grayish-white band.
As the disease progresses, pigment forming cells migrate from the outer edges into the afflicted area, giving the spot, which expands toward the center of the cornea, a gray-pink to a variegated brown and black appearance. Frequently there will be a concurrent inflammation dependent reddening of the conjunctiva. Without treatment, the inflammation will progress to cover the entire cornea and can lead to total blindness.

3. What are the main ways that the disease is usually diagnosed? (rads, blood test, clinical signs, etc)

Some feel that a diagnosis ruling out other cause of keratitis is fundamental. Dry eye syndrome (loss of tear production) and congenital eyelid deformities are important differential diagnoses to consider. Others feel that the clinical signs usually are typical enough for a diagnosis to be made, especially when seen in a German Shepherd dog.

4. Is there a breed, age or sex predisposition to the disease?

Yes, German Shepherd dogs are predisposed to developing Pannus. The disease generally manifests itself in dogs between the ages of three and five. The hereditable succession is not known at this time.

5. Are there predisposing factors for the disease? (ex. A dog that was just boarded might be likely to contract kennel cough)

Sunlight is a trigger for Pannus. Ultraviolet radiation plays an important role as an inciting and propagating factor. In keeping with this, dogs living at high altitudes and low latitudes often are more severely affected.


6. Prevention? (Vaccination? Weight control? Etc.?)

There is no prevention for Pannus. However, there are things the owner of dog with Pannus can do to try to minimize the severity of attacks.

The sun's rays play a major role in the emergence of an acute phase of the disease. Hence, the eyes of an affected dog should be protected from extended exposure to UV light. This includes bright sun on a cloudless day; snow cover, especially at high altitudes and in bright sun; and sunshine during times spent on or near bodies of water.

This means that on days where increased UV exposure is anticipated, dogs should only be walked in the early morning hours, in the evening, or in forested areas, and otherwise should be kept indoors or at locations not subject to direct sun exposure (i.e., in the shade).

If for various reasons UV exposure to the dog cannot be avoided, the animal's eyes must be protected throughout the duration of exposure. This can be accomplished with either specially fitted sun glasses which are, after a short adjustment period, accepted without problems by many dogs, or with the administration of drops containing a UV blocking agent into the conjunctival sacs of the eye. The relatively short term effectiveness of the latter measure requires that the medication be reapplied at specific intervals (approximately hourly).

7. Basic treatment? (as explained to a client)

Treatment is mostly medical, although there are several surgical
procedures used in advanced non responding cases. These include irradiation of the area and the use of liquid nitrogen.
Medically, topical and injectable steroids are commonly employed. Prednisolone acetate 1% suspension and dexamethasone 0.1% suspension are the two main topical corticosteroids used. Injections in to the conjunctiva are also frequently used. These include long acting steroids that give a response of several weeks.

There are three categories of therapy:

1. Corticosteroid therapy, administered by intermittent injections under the mucous membrane of the eye, and by continuous application of eye drops. This is the main line of defense against progression of the disease and most often suffices. However, therapy must be kept up consistently for the rest of the dog's life. Even short periods of interrupted therapy, for example 2 to 4 weeks, may cause severe recurrence with devastating effects on the dog's vision.

2. Beta-irradiation may be used when medication alone proves insufficient.

3. Excision of a superficial layer from the affected area may restore vision in opacified eyes. This is called superficial keratectomy. However, the recurrence rate postoperatively is high and this method remains only as a last resort.

Recently, the use of Cyclosporin A has become popular
now that the drug is commercially available as an ophthalmic. Cyclosporin may improve the response significantly. In some cases the use of topical drugs can be decreased in frequency as the pannus comes under control. Rarely does the problem completely resolve and for the vast majority of cases it requires lifelong therapy.

Recently, Sandoz has modified the formulation of the cyclosporine from which we make up the 1% or 2% solution. The newer formulation is called Cyclosporine Neoral, and it is a microemulsion. A microemulsion can be diluted into other solutions rather than oils. This is advantageous as the oil base of these mixtures would sometimes cause skin irritation around the eye, and could result in oil stains on the furniture if the dog rubbed its face on the sofa for example. The Cyclosporine Neoral microemulsion can be diluted into a bottle of dexamethasone, simplifying the treatment regime.

Doggles.com has quality sunglasses for dogs with this condition.

Marjorie
http://www.gsdbbr.org --> The German Shepherd Dog Breed Betterment Registry (including frozen/chilled semen database)
Please utilize this registry to ensure a healthy future for our breed!
Be PROACTIVE!
 http://mzjf.com --> The Degenerative Myelopathy Support Group