Integumentary Diseases

CONGENITAL AND INHERITED ANOMALIES

    1.     Congenital anomalies of the skin

  1. A.     Epitheliogenesis imperfecta (aplasia cutis)

Epitheliogenesis imperfecta (aplasia cutis) is a congenital discontinuity of squamous epithelium. It is rare in dogs and cats. For more information click here or call your veterinarian.

  1. B.      Nevus & hamartoma

A nevus is a circumscribed developmental defect of the skin, while a hamartoma is a hyperplastic mass formed as a result of a developmental defect in any organ. For more information click here or call your veterinarian.

  1. C.     Dermoid sinuses or cysts

Dermoid sinuses or cysts occur in Thoroughbred horses and Rhodesian Ridgebacks (in which they are inherited) and occasionally other breeds of dogs. These are cystic structures lined with skin into which exfoliated skin, hair, and glandular debris accumulate. For more information click here or call your veterinarian.

  1. D.     Follicular cysts

Follicular cysts develop by abnormal hair follicle morphogenesis and by retention of follicular or glandular products. For more information click here or call your veterinarian.

    2.     Hereditary Alopecia and Hypotrichosis

  1. A.     Alopecia

Alopecia is the absence of hair; hypotrichosis, which is much more common, is the presence of less hair than normal. Although these defects can be generalized, they commonly develop in patterns that spare the extremities or correlate with hair color. For more information click here or call your veterinarian.

  1. B.      Follicle dysplasias

In dogs, there are several tardive follicle dysplasias, including color dilution alopecia. In cats, follicular dysplasia occurs in the Devon Rex. For more information click here or call your veterinarian.

    3.     Hyperplastic and Seborrheic Syndromes

Many anomalies affect keratinization; some are associated with hereditary hypotrichoses, while others are associated with systemic metabolic derangements. For more information click here or call your veterinarian.

4.     Pigmentary Abnormalities

  1. A.     Albinism

Albinism appears to be rare in domestic animals. True albinism is always associated with pink or pale irises and with visual defects and increased risk of solar radiation-induced neoplasms of the skin. For more information click here or call your veterinarian.

  1. B.      Vitiligo

Pigmentary abnormalities may be acquired, and some of these may be hereditary or familial as in vitiligo. For more information click here or call your veterinarian.

  1. C.     Lentigo

Lentigo in orange and orange-faced male cats is marked by the development of asymptomatic, pigmented macules. For more information click here or call your veterinarian.

  1. D.     Acquired aurotrichia

Acquired aurotrichia of Miniature Schnauzers is a familial syndrome in which hair along the dorsal midline changes to golden from the normal black or gray of this breed. For more information click here or call your veterinarian.

    5.     Defects of structural integrity

  1. A.     Cutaneous asthenia (dermatosparaxis, Ehlers-Danlos syndrome)

Cutaneous asthenia is a group of syndromes characterized by defects in collagen production. For more information click here or call your veterinarian.

  1. B.      Epidermolysis bullosa syndromes

The epidermolysis bullosa syndromes are a group of congenital and hereditary diseases that result from defects in the dermal-epidermal attachment structures. For more information click here or call your veterinarian.

  1. C.     Canine benign familial chronic pemphigus

Canine benign familial chronic pemphigus is a mechanobullous disorder that is caused by a defect in cell-to-cell adhesion in the epidermis. For more information click here or call your veterinarian.

  1. D.     Cutaneous mucinosis

Cutaneous mucinosis is thought to be a familial problem in some lines of Chinese Shar-Peis. Normal Shar-Peis have more cutaneous mucin than other dogs, but in some young dogs, cutaneous mucin formation in the dermis is so excessive that the skin exhibits pronounced folding and mucinous vesiculation. For more information click here or call your veterinarian.

    6.     Cutaneous manifestations of multisystemic and metabolic defects

  1. A.     Familianl vasculopathy

Familial vasculopathy has been described in German Shepherds and Jack Russell Terriers. In these dogs, the skin lesions develop shortly after the first set of puppy vaccinations and seem to be exacerbated after subsequent vaccinations. For more information click here or call your veterinarian.

  1. B.      Familial dermatomyositis

Familial dermatomyositis is an idiopathic inflammatory disease of the skin and muscles of young Collies and Shetland Sheepdogs. For more information click here or call your veterinarian.

  1. C.     Hereditary lupoid dermatosis

Hereditary lupoid dermatosis of German Shorthaired Pointers is first noted when the dog is ~6 mo old. It begins with scaling and crusting on the head and dorsum and quickly progresses to generalized scaling with erythema. For more information click here or call your veterinarian.

  1. D.     Hereditary zinc deficiency syndromes

Hereditary zinc deficiency syndromes are best known in cattle and have also been described in dogs. For more information click here or call your veterinarian.

  1. E.      Tyrosinemia

Tyrosinemia has been described in 1 German Shepherd puppy. It was compared to a type of tyrosinemia in humans and thus thought to be hereditary. For more information click here or call your veterinarian.

    7.     Congenital and hereditary neoplasms multiple mamartomas

Congenital tumors are rare in dogs and cats. One dog with a giant congenital pigmented nevus had a malignant melanoma develop within the lesion. In cats, familial benign mastocytosis is described in young Siamese cats. For more information click here or call your veterinarian.

II.      Allergic Inhalant Dermatitis (Atopy)

Allergic inhalant dermatitis is a common form of allergy in dogs and cats. It is generally accepted to be a Type I (IgE or IgG) hypersensitivity and is believed to affect ~10% of the canine population. Its incidence in cats has not been reported. For more information click here or call your veterinarian.

III.      Food allergy

Food allergy is ~10% as common as atopy in dogs and about as common as atopy in cats. The history is that of a nonseasonal pruritus, with little variation in the intensity of pruritus from one season to another in most cases. For more information click here or call your veterinarian.

IV.      Urticaria (Hives, Nettle rash)

Urticaria is characterized by multiple plaque-like eruptions that are formed by localized edema in the dermis and that often develop and disappear suddenly. For more information click here or call your veterinarian.

V.      Dermatophilosis (Dermatophilus infection, Cutaneous streptothricosis, Lympy wool, Strawberry footrot)

This infection of the epidermis, which is seen worldwide but is more prevalent in the tropics, is also erroneously called mycotic dermatitis. The lesions are characterized by exudative dermatitis with scab formation. Controlling ectoparasites are methods used to break the infective cycle. For more information click here or call your veterinarian.

VI.      Interdigital furunculosis

Interdigital furuncles, often incorrectly referred to as interdigital cysts, are painful nodular lesions located in the interdigital webs of dogs. For more information click here or call your veterinarian.

VII.      Pyoderma

Pyoderma literally means “pus in the skin” and can be caused by infectious, inflammatory, and/or neoplastic etiologies; any condition that results in the accumulation of neutrophilic exudate can be termed a pyoderma. Most commonly, however, pyoderma refers to bacterial infections of the skin. Pyodermas are common in dogs and less common in cats. For more information click here or call your veterinarian.

VIII.      Pox infection in cats

Poxvirus infection in domestic cats has occurred sporadically in the UK and possibly Western Europe. Affected cats usually have multiple skin lesions, although respiratory and other signs also may be seen. For more information click here or call your veterinarian.

IX.      Dermatophytosis (Ringworm)

Dermatophytosis is an infection of keratinized tissue (skin, hair, and claws) by one of the 3 genera of fungi collectively called dermatophytes. These pathogenic fungi are found worldwide, and all domestic animals are susceptible. In developed countries, the greatest human health consequences come from dermatophytosis of domestic cats. For more information click here or call your veterinarian.

X.      Cuterebra infestation

This opportunistic, parasitic infestation of dogs, cats, and ferrets is caused by the rodent or rabbit botfly, Cuterebra spp. Flies are usually host- and site-specific relative to their life cycle. However, rabbit Cuterebra are less host-specific and are usually associated with dog and cat infestations. For more information click here or call your veterinarian.

XI.      Fleas and flea allergy dermatitis

In North America, only a few species commonly infest dogs and cats. However, by far the most prevalent flea on dogs and cats is C felis. Cat fleas cause severe irritation in animals and humans and are responsible for flea allergy dermatitis. Flea allergy dermatitis (FAD) or fleabite hypersensitivity is the most common dermatologic disease of domestic dogs in the USA. Cats are also afflicted with FAD, which is one of the major causes of feline miliary dermatitis. For more information click here or call your veterinarian.

XII.      Flies

1.     Dipterans with biting mouthparts

Blood-feeding dipterans can be classified in several ways based on which sexes feed on vertebrate blood and on food preference. For more information click here or call your veterinarian.

    2.     Dipterans with nonbiting mouthparts

The eye gnats or the eye flies are very small (1.5-2.5 mm long) flies that frequently congregate around the eyes. Some species are attracted to the genital organs of mammals; for example, H pallipes clusters around a dog’s penis. For more information click here or call your veterinarian.

    3.     Dipterans that produce myiasis

Larval stages of facultative myiasis-producing flies are usually associated with skin wounds of any domestic animal that have become contaminated with bacteria or with a matted hair coat contaminated with feces. With respect to prevention, owners should be educated about the effectiveness of treating all skin wounds. For more information click here or call your veterinarian.

XIII.      Helminths of the skin

    1.     Dracunculus Infections

Dracunculus insignis is found mainly in the subcutaneous connective tissues of the legs of dogs. For more information click here or call your veterinarian.

    2.     Pelodera Dermatitis (Rhabditic dermatitis)

This rare, nonseasonal, acute dermatosis results from invasion of the skin by larvae of the free-living saprophytic nematode Pelodera (Rhabditis) strongyloides. For more information click here or call your veterinarian.

XIV.      Lice (Pediculosis)

Dogs are occasionally infested the dog sucking louse, and the biting louse. Animals in poor health may become heavily infested. The cat louse is a chewing louse that occasionally parasitizes cats. The louse may be seen more frequently on older, longhaired cats that are unable to groom themselves. For more information click here or call your veterinarian.

XV.      Mange (Cutaneous acariasis, Mite infestation)

1.     Sarcoptic Mange (Canine Scabies)

Sarcoptes scabiei var canis infestation is a highly contagious disease of dogs found worldwide. The mites are fairly host-specific, but animals (including humans) that come in contact with infested dogs can also be affected. For more information click here or call your veterinarian.

    2.     Notoedric Mange (Feline Scabies)

This rare, highly contagious disease of cats and kittens is caused by Notoedres cati, which can opportunistically infest other animals, including humans. Pruritus is severe. For more information click here or call your veterinarian.

    3.     Otodectic Mange

Otodectes cynotis mites are a common cause of otitis externa especially in cats but also in dogs. Mites are usually found deep in the external ear canal, but occasionally are seen on the body. For more information click here or call your veterinarian.

    4.     Cheyletiellosis (Walking Dandruff)

Cheyletiella blakei infests cats and C yasguri infests dogs. This disease is very contagious, especially in animal communities. Human infestation is frequent. For more information click here or call your veterinarian.

    5.     Canine Demodicosis

This skin disease of dogs occurs when large numbers of Demodex canis mites inhabit hair follicles and sebaceous glands. In small numbers, these mites are part of the normal flora of the skin of dogs and cause no clinical disease. For more information click here or call your veterinarian.

    6.     Feline Demodicosis

Two species of mites cause disease in cats. Demodex cati is thought to be a normal inhabitant of feline skin. The other species of Demodex (usually named D gatoi) is shorter, with a broad abdomen, and is found only in the stratum corneum. Feline demodicosis is uncommon. For more information click here or call your veterinarian.

    7.     Trombiculosis

This common, seasonal noncontagious acariasis is caused by the parasitic larval stage of free-living mites of the family Trombiculidae. It can affect domestic carnivores, other domestic or wild mammals, birds, reptiles, and humans. For more information click here or call your veterinarian.

XVI.      Ticks

    1.     Important Ixodid ticks

  1. A.     Amblyomma SPP 

Amblyomma ticks are large, 3-host parasites. They have eyes and long, robust mouthparts. For more information click here or call your veterinarian.

  1. B.      Dermacentor spp and Anocentor sp 

The Rocky Mountain wood tick and the American dog tick produce tick paralysis in livestock, wildlife, and humans. They are the chief vectors of Rickettsia rickettsii, the agent of Rocky Mountain spotted fever. For more information click here or call your veterinarian.

  1. C.     Haemaphysalis spp 

A few African species that evolved together with carnivores now parasitize domestic dogs. For more information click here or call your veterinarian.

  1. D.     Ixodes spp 

Hosts are a wide variety of birds and mammals and a few reptiles. I scapularis is a vector of Borrelia burgdorferi, the agent of Lyme disease; it is also a vector of Babesia microti, the agent of human babesiosis. This tick also is a vector of human granulocytic ehrlichiosis. For more information click here or call your veterinarian.

  1. E.      Rhipicephalus spp 

The best-known African rhipicephalid, the kennel tick or brown dog tick, has traveled worldwide with domestic dogs. For more information click here or call your veterinarian.

    2.     Important Argasid ticks

Otobius megnini, which is exceedingly specialized biologically and structurally, infests the ear canals. Cattle, horses, goats, sheep, dogs, and humans are similarly infested. For more information click here or call your veterinarian.

XVII.      Tumors of the skin and soft tissues

    1.     Epidermal and hair follicle tumors

  1. A.     Benign, Nonvirus-associated Papillomatous Lesions 

 

  1. a.      Epidermal hamartomas (nevi) are rare proliferations identified only in dogs, most often in the young. The disease may be heritable in Cocker Spaniels. For more information click here or call your veterinarian.

 

  1. b.      Canine warty dyskeratomas are rare, benign neoplasms of uncertain derivation but with histologic features of follicular or apocrine neoplasms (or both). For more information click here or call your veterinarian.

 

  1. B.      Basal Cell Tumors and Basal Cell Carcinomas (Basal cell epitheliomas, Basaliomas, Trichoblastomas, Basosquamous cell carcinomas)

 

  1. a.      Basal cell tumors represent a heterogeneous group of cutaneous epithelial neoplasms recognized commonly in dogs and cats. For more information click here or call your veterinarian.

 

  1. b.      Basal cell carcinomas are more frequently recognized in cats than in dogs. In cats, they develop most frequently in aged animals. Persians are predisposed. For more information click here or call your veterinarian.

 

  1. C.     Intracutaneous Cornifying Epitheliomas (Keratoacanthoma, Infundibular keratinizing acanthoma)

Intracutaneous cornifying epitheliomas are benign neoplasms of dogs and possibly cats. As in human keratoacanthomas, these lesions most likely arise from the hair follicle and not from the interfollicular epidermis. For more information click here or call your veterinarian.

  1. D.     Squamous Cell Carcinomas (Epidermoid carcinomas, Prickle cell carcinomas)  

Thought to arise from either the epidermis or the epithelium of the superficial (infundibular) regions of the outer root sheath of the hair follicle, squamous cell carcinomas have been recognized in all domestic animals. For more information click here or call your veterinarian.

  1. E.      Keratinized Cutaneous Cysts

Most of these are malformations of the hair follicle. They are common in dogs; occasionally identified in cats. For more information click here or call your veterinarian.

  1. F.      Tumors of the Hair Follicle

The hair follicle is a complex structure composed of 8 different epithelial layers. Hair-follicle tumors display a similar complexity, and much work needs to be done to characterize them further. They are most common in dogs, less frequent in cats. For more information click here or call your veterinarian.

  1. G.     Cutaneous Apocrine Gland Tumors 

Apocrine gland tumors and malformations are most common in dogs and cats. Three diseases of apocrine glands of haired skin have been characterized. For more information click here or call your veterinarian.

  1. H.     Apocrine Gland Tumors of Anal Sac Origin 

These have been definitively identified only in dogs, although anecdotal reports suggest they may also occur in cats. They most commonly appear as deep, firm, nodular masses near the anal sac. For more information click here or call your veterinarian.

  1. I.       Eccrine Gland Tumors 

Eccrine glands are the coiled, tubular, sweat glands present on the footpads of carnivores. Tumors derived from these glands are extremely rare and have been identified only on the footpads of dogs and cats. For more information click here or call your veterinarian.

  1. J.       Sebaceous Gland Tumors

Tumors and tumor-like conditions of sebaceous glands are common in dogs, infrequent in cats, and rare in other domestic animals. For more information click here or call your veterinarian.

  1. K.      Hepatoid Gland Tumors  (Perianal gland tumors, Circumanal gland tumors) 

These common neoplasms arise from modified sebaceous glands that are most abundant in the cutaneous tissues around the anus. For more information click here or call your veterinarian.

  1. L.      Papillomas 

Multiple papillomas (papillomatosis) of skin or mucosal surfaces generally are seen in younger animals and are usually caused by viruses. Papillomatosis is most common in cattle, horses, and dogs. Single papillomas are more frequent in older animals, but they may not always be caused by viral infection. For more information click here or call your veterinarian.

    2.     Connective tissue tumors

  1. A.     Benign Fibroblastic Tumors

 

  1. a.      Collagenous nevi are benign, focal, developmental defects associated with increased deposition of dermal collagen. They are common in dogs, uncommon in cats. For more information click here or call your veterinarian.

 

  1. b.      Generalized nodular dermatofibrosis (dermatofibromas), recognized rarely in German Shepherds (believed to be an inherited) and even less commonly in other canine breeds, is a syndrome in which multiple collagenous nevi are associated with renal cystadenocarcinomas and, in females, multiple uterine leiomyomas. For more information click here or call your veterinarian.

 

  1. c.      Acrochordons (cutaneous tags, soft fibromas, fibrovascular papillomas) are distinctive, benign, cutaneous lesions of older dogs. For more information click here or call your veterinarian.

 

  1. d.      Fibromas are discrete, generally cellular proliferations of dermal fibroblasts. Fibromas occur in all domestic species but are primarily a tumor of aged dogs. For more information click here or call your veterinarian.

 

  1. B.      Soft-tissue Sarcomas

This group of malignancies includes fibromatoses, fibrosarcomas, malignant fibrous histiocytomas, neurofibrosarcomas, leiomyosarcomas, rhabdomyosarcomas, and variants of liposarcomas, angiosarcomas, synovial cell sarcomas, mesotheliomas, and meningiomas. For more information click here or call your veterinarian.

  1. C.     Fibrohistiocytic Tumors
  2. a.      Canine fibrous histiocytoma

A lesion called canine fibrous histiocytoma is recognized at the episcleral junction and cornea primarily in young to middle-aged (2-4 yr old) Collies, but the histologic features are more suggestive of a granulomatous inflammatory response than a neoplasm. For more information click here or call your veterinarian.

  1. b.      Malignant fibrous histiocytomas are most frequently found in the skin and soft tissues of cats, and rarely in the skin of other domestic species, including dogs. For more information click here or call your veterinarian.

 

  1. D.     Peripheral Nerve Sheath Tumors

In dogs and cats, peripheral nerve sheath tumors of the skin are found in older animals. For more information click here or call your veterinarian.

  1. E.      Adipose Tissue Tumors
  2. a.      Lipomas are benign tumors of adipose tissue, perhaps more accurately characterized as hamartomas. They are common in dogs, occasionally identified in cats. For more information click here or call your veterinarian.

 

  1. b.      Infiltrative lipomas (intra- and intermuscular lipomas) are rare in dogs and even less common in cats. In dogs, they are most common in middle-aged females, usually on the thorax and limbs. For more information click here or call your veterinarian.

 

  1. c.      Liposarcomas are rare neoplasms in all domestic animals. Most are recognized in older male dogs in which they usually develop on the trunk and extremities. In cats, feline leukemia virus infection has been infrequently associated with their development. For more information click here or call your veterinarian.

 

  1. F.      Vascular Tumors
  2. a.      Hemangiomas of the skin and soft tissues are benign proliferations that closely resemble blood vessels. They are most commonly identified in dogs, occasionally in cats. For more information click here or call your veterinarian.

 

  1. b.      Hemangiopericytomas (canine spindle-cell sarcoma, canine malignant fibrous histiocytoma, canine neurofibrosarcoma, canine perineuroma) are common in dogs and rare in cats (if they occur at all). For more information click here or call your veterinarian.

 

  1. c.      Angiosarcomas, arguably the most aggressive of all soft-tissue tumors, are composed of cells that have many functional and morphologic features of normal endothelium. For more information click here or call your veterinarian.

 

  1. G.     Cutaneous Smooth Muscle Tumors

Because they either are not recognized or do not occur with any regularity in domestic animals, cutaneous smooth muscle tumors (leiomyomas or leiomyosarcomas) are diagnosed rarely. For more information click here or call your veterinarian.

    3.     Lymphocytic, histiocytic, and related cutaneous tumors

  1. A.     Lymphoid Tumors of the Skin

 

  1. a.      Canine extramedullary plasmacytomas (atypical histiocytomas, cutaneous neuroendocrine tumors, reticulum cell sarcomas, cutaneous nodular amyloidosis) are relatively common cutaneous tumors. For more information click here or call your veterinarian.

 

  1. b.      Cutaneous lymphosarcoma may occur as a disease in which the skin is the initial and primary site of involvement, or it may be secondary to systemic, internal disease. For more information click here or call your veterinarian.

 

  1. c.      Epitheliotropic cutaneous lymphosarcoma (ECL, mycosis fungoides) is the most frequently recognized form of cutaneous lymphosarcoma in dogs and arguably cats. For more information click here or call your veterinarian.

 

  1. B.      Cutaneous Mast Cell Tumors (Mastocytomas, Mast cell sarcomas)  

These tumors are the most frequently recognized malignant or potentially malignant neoplasms of dogs. For more information click here or call your veterinarian.

  1. C.     Tumors with Histiocytic Differentiation 

These comprise a group of poorly defined skin diseases all characterized by a proliferation of histiocytes (tissue macrophages) in the absence of any known stimulus. For more information click here or call your veterinarian.

  1. D.     Transmissible Venereal Tumors 

Canine transmissible venereal tumors (TVT) are cauliflower-like, pedunculated, and nodular, papillary, or multilobulated in appearance.These can also develop initially on haired skin due to inoculation via cutaneous injuries. For more information click here or call your veterinarian.

    4.     Tumors of melanocytic origin

  1. A.     Dogs

Melanocytomas of the skin are diagnosed much more frequently than malignant melanomas. They most commonly develop on the head and forelimbs in middle-aged or older dogs. For more information click here or call your veterinarian.

  1. B.      Cats

Cutaneous melanocytic neoplasms are uncommon and most often identified on the head (especially the pinnae), neck, and distal extremities in middle-aged or older cats. For more information click here or call your veterinarian.

    5.     Metastatic tumors

The spread of a primary neoplasm to the skin is unusual in domestic animals. It is occasionally identified in dogs; less commonly in cats. For more information click here or call your veterinarian.

XVIII.      Acanthosis nigricans

Acanthosis nigricans describes a clinical reaction pattern in dogs characterized by axillary and inguinal hyperpigmentation, lichenification, and alopecia. For more information click here or call your veterinarian.

XIX.      Eosinophilic granuloma complex

The etiology of this group of diseases that affects cats and dogs has focused on an underlying hypersensitivity reaction. This is particularly true in cats. For more information click here or call your veterinarian.

XX.      Hygroma

A hygroma is a false bursa that develops over bony prominences and pressure points, especially in large breeds of dogs. Repeated trauma from lying on hard surfaces produces an inflammatory response, which results in a dense-walled, fluid-filled cavity. For more information click here or call your veterinarian.

XXI.      Miscellaneous systemic dermatoses

A number of systemic diseases produce various lesions in the skin. Usually, the lesions are noninflammatory, and alopecia is common. For more information click here or call your veterinarian.

XXII.      Nasal dermatoses (Collie nose, Nasal solar dermatitis)

Nasal dermatoses of dogs may be caused by many diseases. Lesions may affect the bridge of the nose, the planum nasale, or both. In pyoderma, dermatophytosis, and demodicosis, the haired portions of the nose are affected. For more information click here or call your veterinarian.

XXIII.      Photosensitization: Aberrant Pigment Metabolism

Type II photosensitivity due to aberrant pigment metabolism is known to occur in cats. In this syndrome, the photosensitizing porphyrin agents are endogenous pigments that arise from inherited or acquired defective functions of enzymes involved in heme synthesis. For more information click here or call your veterinarian.

XXIV.      Seborrhea

Seborrhea is a skin disease in dogs that is characterized by a defect in keratinization or cornification. For more information click here or call your veterinarian.