Page 52 - Canine-Diseases

that affect dogs: pemphigus foliaceus, pemphigus erythematosus, increased risk of metastasis and carcinomas tend to grow more
pemphigus vulgaris, and pemphigus vegetans. Pemphigus rapidly. Most anal sac tumours are adenocarcinomas and tend
foliaceus, is the most common form in which the antibodies target to metastasise to regional lymph nodes giving a poor prognosis.
the molecules responsible for adhesion between keratinocytes. Hyperadrenococrticism may increase the likelihood of tumour
Middle-aged dogs are most commonly affected and lesions occurrence in females or recurrence in treated male dogs. Breeds
often start on the face and ears, fluctuate in severity and extend at an increased risk of developing perianal gland tumor include
to include the rest of the body, especially feet and groin. Most Siberian Huskies, Samoyeds, Pekinese, Cocker Spaniels, Brittany
common lesions are macules progressing to pustules and crusts Spaniels, Lhasa Apsos, Shih Tzus, and Beagles
with erosions. Nikolsky sign may be present. Cause is often
unknown but may be induced by infections, neoplasia or drug Pericardial disease: Affects the pericardium, which is a membrane
administration. Pemphigus erythematosus is less common with that covers the heart and consists of two layers, the visceral layer
erythematous, pustular, crusting lesions generally appearing on the and the parietal layer, and the space between the layers called the
face and ears. Loss of pigment on the nose may be seen more often pericardial space. The most common disorder of the pericardium
in this presentation, allowing ultraviolet light to aggravate lesions. is inflammation (pericarditis). Others include pericardial effusion
Pemphigus vulgaris is also a less common and but aggressive and fibrosis of the pericardium. Pericardial disease can occur
form. Lesions may be seen at any age and most commonly occur in any dog, but is more common in larger breeds, especially
as vesicles, bullae, ulcers or erosions at mucocutaneous junctions the Golden Retrievers, where it is often associated with cancer.
and in the mouth. Lesions may also be present in other skin areas. Pericardial disease is considered rare, but its presence may be life-
Nikolsky sign may be present. Pemphigus vegetans is very rare threatening.
in the dog. Diagnosis is based on clinical signs, biopsies with
histopathology, and immunofluorescence studies. Pemphigus Pericardial effusion: Is the abnormal accumulation of fluid
foliaceus is most commonly seen in Chow Chows, Akitas, Cocker in the pericardial space and the most common disease of the
Spaniels, Labrador Retrievers, Dachshunds, Doberman Pinschers, pericardium in dogs. It is usually serous (clear or yellow fluid)
Newfoundlands, and English Bulldogs. Breeds predisposed to or serosanguinous (bloody fluid). Serious accumulation is caused
Pemphigus erythematosus include German Shepherds, Collies, by heart failure, peritoneopericardial diaphragmatic hernias,
and Shetland Sheepdogs. uremia, pericardial cysts, or hypoalbuminemia. Serosanguinous
accumulation can be caused by cancer, usually hemangiosarcoma,
Perianal fistula: Perianal refers to the area immediately idiopathic disease, trauma, clotting disorders, or left atrial rupture.
surrounding the anus or termination of the digestive tract. A fistula Rarely pericardial effusion can be caused by infection and consist
is an abnormal connection that forms between two tissues, organs, of pus. A secondary condition, referred to as cardiac tamponade,
or vessels that normally do not connect. Perianal fistula is a results from this retention of fluid, as the swelling of fluid applies
painful, chronic and progressive disease of the tissues surrounding pressure on the beating heart, compressing it and restricting its
the anus and rectum. Primary lesions are ulcerations and sinus ability to pump blood. Pericardial effusion that is severe enough to
formation of varying size and depth. The lesions vary in severity cause tamponade may result in sudden death. Common presenting
but at first appear as small oozing holes in the skin. Presenting signs of pericardial effusion include lethargy, respiratory difficulty,
signs could include straining to defecate, constipation, increased collapse, reduced appetite, vomiting, and abdominal distention.
frequency of defecation, diarrhoea, reluctance to elevate the tail Less commonly dogs have increased thirst, weakness, or coughing.
(painful), excessive licking around the anal region or systemic
signs such as weight loss and lethargy. Perianal fistulas are a Perineal hernia: Result from weakening or complete failure of
chronic, debilitating disease that requires lifelong monitoring the muscular diaphragm of the pelvis. Dogs with perineal hernias
and, potentially, lifelong treatment. German Shepherds are will demonstrate a swelling adjacent to the rectum on one or both
most notoriously affected, although Irish Setters and Labrador sides coupled with signs of constipation, difficulty defecating,
Retrievers are among the breeds that seem over-represented. lethargy, difficulty urinating, and altered tail carriage. A hernia
of the perineal region is more common in older animals than in
Perianal gland tumor (Hepatoid tumor): The perianal glands younger as the region of the animal’s body becomes weaker over
are modified sebaceous gland and are also sometimes referred to time. Breeds predisposed to perineal hernia include Pekingese,
as hepatoid glands or circumanal glands. Thus, other names for Boston Terriers, Welsh Corgis, Dachshunds, Boxers, Kelpies,
perianal gland adenomas (a benign tumor of glandular tissue) are Collies, and Old English Sheepdogs.
hepatoid gland adenoma and circumanal gland adenoma. Perianal
gland tumor is a group of common hormone-responsive tumours in Persistent pupillary membrane: Is a condition of the eye
the dog. Most arise from the circumanal glands and less frequently involving remnants of a fetal membrane that persist as strands
from anal sac glands. Tumours tend to occur in older dogs (11+ of tissue in the eye. They are remnants of blood vessels which
years) and may be found next to the anus, on the tail, perinueum, supplied nutrients to the developing lens of the eye before birth.
prepuce, thigh, or dorsal lumbo-sacral area. Lesions are generally Depending upon the location and extent of these strands, they
firm and located in the dermal and epidermal tissues on palpation. may interfere with vision. They may bridge from iris to iris across
They may or may not be well circumscribed. Reported circumanal the pupil, iris to cornea (may cause corneal opacities), or iris to
tumors include hyperplasia, adenomas, and carcinomas. Most of lens (may cause cataracts), or they may form sheets of tissue in
these may be benign however larger lesions are reported to be at the anterior chamber of the eye. Persistent pupillary membrane

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