Diseases of the Integumentary System

1. Diseases of the Integumentary System Casey Conway Jeannie Stall , R.V.T. Google Images

2. Skin • Largest organ • 3 layers: epidermis, dermis, hypodermis • Barrier between animals body and the environment • Protects from physical, chemical, microbiological • Important indicator of internal disease • One of the most common problems

3. Canine Skin

4. Ectoparasites • Ear Mites • Fleas • Ticks • Mange • Warbles (Cuterebra) • Maggots • Lice

5. Ear Mites • Surface of skin – external ear canal • Feed on epidermal debris • Clinical Signs • Brown, black crusty exudate • Irritating, scratching • Scrapes, wounds • Diagnose: otoscope – see large adults, ear swab, microscopic evaluation • Tx: Clean ears, medication (Tresaderm)

6. Fleas • Blood-sucking, mammals and birds • Severe skin irritation – frequent bites • Flea saliva is highly antigenic in some animals causing an allergic dermatitis • Intermediate host – dog tapeworm (dipylidium) • Vector dz • Clin. Signs: fleas, flea dirt, skin lesions - bites

7. FAD (Flea Allergy Dermatitis)

8. Fleas cont. • Tx: several products – OTC gen. not effective • Topical: sprays, dips, powders, shampoos • Sprays/powders use combo ingredients • Specific species/age – VERY CAREFUL • Dips – residual effect – can be very toxic • Shampoos have no residual effect

9. Fleas cont. • Systemic: spot-ons, oral, inj. • Advantage – mo. spot-on • Program – monthly tablet or 6 mo. injection – absorbed by fatty tissue – bloodstream • Frontline – mo. spot-on – not true systemic • Sentinel – mo. Tab • Revolution – mo spot-on • Capstar- Tablet / Fast but only lasts 24 hrs.

10. Fleas cont. • Huge client education issue • Not just one animal in household/family • Even if they never go outside • Will bite/feed on humans but are generally species specific • Can be dormant for months • Clean ,clean ,clean !!!!

11. Ticks • Blood-sucking arthropod • Not species specific – all warm blooded animals including humans • Heavy infestation – anemia • Transmit many dz – bact, viral, rickettsial, protozoan • Bites, vector dz, neurotoxin in saliva of 12 species causes tick paralysis in dogs

12. Ticks cont. • Clin. Signs – tick (lump) on the animal • Weak, pale MM (lg number) • Flaccid paralysis • Arthritis-like symptoms, joints (lymes) • Tx – manual removal of all ticks • Topicals, sprays, powders, dips • Frontline, advantix, revolution, • Treat environment • Prevention is best!

13. Mange • 3 primary “mange” mites in dogs & cats • Demodectic, sarcoptic, notoedric • Demodectic mange (non-pruritic) • Mites live in the hair follicles of most dogs and cats • Localized: 3m-1y age, hx, alopecia – head, forelegs, trunk. “Red Mange” • Generalized: febrile, entire body, secondary bact skin infx - pustules

14. Demodectic Mange cont. • Dx skin scrape – mite identification • Tx age, lesions, vet preference • Mitaban dip • Ivermectin – off-label • Not contagious • Generalized form can be fatal

15. Sarcoptic Mange • Intensely pruritic – unlike demodex • Highly contagious • Mites burrow in skin • Can infect humans – only live for a few days off original host • Rarely infects cats

16. Sarcoptic Mange cont. • Clin signs – red lesions – ears, elbows, trunk • Itch itch itch • Secondary bact infx • Progression is more severe • Dx with skin scrape – deep in epidermis • Biopsy • Tx dips, ivermectin (off-label)

17. Warbles (Cuterebra) • Fly lays eggs in the soil • Grub penetrates host skin, mature • Leaves as an adult fly • Fistula (opening) to breathe • Young animals – esp. rabbits • Large swelling behind ears/neck • Incise fistula and remove larva • Flush wound, abx • NEVER CRUSH! Anaphylactic Rxn

18. Cuterebra Hole

19. Maggots ( Myiasis) • Adult flies lay eggs in wet, warm, damaged skin on animal • Eggs hatch – larvae – highly destructive • Large ulcerated area • Heavy coats, neglect, matted hair, bad odor, painful reaction • Clip hair, flush wounds, manually remove all larvae (avoid dips – open wound) • Daily wound mgmt – must! Abx, keep inside

20. Lice • Don’t effect humans – host specific • Dz of neglect • Pets agitated, intense itching, anemia • Presence of lice in coat diagnostic • Dips, dusts, shampoos. • Clip hair • Nits form cocoons on hair shafts

21. Fungal Infections • Ringworm (microsporumcanis) • Circular patch of alopecia – face/head • Zoonotic! Esp. children, elderly • Wood’s lamp(Black light)– 50% fluoresce yellow/green • Culture, clip area, tx antifungal until 2 wk post • Oral therapy • Hairs shed from infx animal remain contagious for up to 18 months!

22. Ringworm

23. Pyoderma • Bacterial infection of the skin • Primary • Secondary • Superficial • Deep • Superficial: hot spots, impetigo, acne, skin-fold pyoderma

24. Hot Spots • Acute moist dermatitis • Infection and inflammation • Any break or irritation in skin • 95% staph - bad fast – very itchy • Tx: clip/clean, Cortisone inj. • Rx Cortisone spray or tabs • E-collar • +/- abx

25. Impetigo • Strep – lesions – unhealthy animal • Culture and sensitivity • Systemic abx • Shampoo, topical • Not contagious

26. Superficial Pyoderma cont. • Acne • Chronic, worse cats • Clean bowls • Skin-fold pyoderma • Redundant tissue traps moisture/heat • Long-term tx • Surgical removal of extra skin • Breeds – brachycephalic • Deep pyoderma • Papules, pustules, usually drug resistant

27. Feline Acne • Comedomes

28. Anal glands • Location of glands @ 4 & 8 o’clock positions Duct openings @ 2 & 10 o’clock positions • Impaction • Chronic infection • Rupture – surgical tx • Expression – natural with bm, manually • Lavage, instill abx • Oral abx

29. Infected Anal Gland

30. Tumors / Cancer • Benign – no harm • Malignant – may result in death • Localized • Invasive • Specialized area so many types • Benign skin tumors • Histiocytomas, lipoma , papilloma, sebaceous cyst (fatty tumor), ( warts) , ( within skin)

31. Tumors / Cancer cont. • Malignant skin tumors • Basal cell carcinoma • Fibrosarcoma (not vx-induced) • Feline Fibrosarcoma (vx-induced) • Mast cell tumors Prior trt.- Sx. & Millipore H2O New trt.- Kinavet CA1

32. Tumors cont Melanoma • Benign – small • Malignant – large • Biopsy, surgical excision • Metastasize readily • Poor prognosis • Recurrence is common

33. Tumors cont Perianal tumors (Adenoma, Adenocarcinoma) • Small, slow-growing, close to the anus • Ulcerated • Location, biopsy, surgical excision • Castration aids in preventing recurrence • Radiation • Cryosurgery

34. Tumors cont Squamous cell carcinoma • Raised, ulcerated, cauliflower-like mass • Biopsy, surgical excision • Radiotherapy • Cryosurgery • Recurrence is common

35. Horses • Skin issues common • Age, season, confinement • Herd or alone • Location, geography • Insects!! Huge part of equine management.

36. Insect Hypersensitivity • Systemic allergic rxn to insect bites (gnats) • Intense pruritis, alopecia, uticaria, lesions • Dx with clin. signs and presence of insects • Tx insect control, fly spray, manure mgmt • Antihistamines generally don’t help • If lesions bad – abx

37. Fly Bite Dermatitis • Wheals, pustules, nodules • Treat w/ fly spray or VIP oint. • Insect control/management • Care of wounds

38. Lice • One of the most common ectoparasites on horses • Sucking lice – more damage, live off blood • Biting or Chewing lice – live off dead cells and debris in the skin • Winter – longer coat • Direct contact transmission, carried on objects • Itching – tail, mane • See adults, eggs in the hair • Shampoo (pyrethrin), tx environment, clip • Tx all horses in herd/barn • Ivermectin effect more against sucking lice than biting

39. Mites • Normal inhabitant of skin • Dz in immunocompromised animals • Itching lesions • Skin scrape • Dips • Ivermectin

40. Ticks • Bite sensitivity – ears, face, neck, groin, tail • Some severe systemic hypersensitivity • Tick paralysis • Removal • Pyrethrin dips • Frontline (off-label)

41. Onchocerciasis • Nematode parasite • Adults live in ligaments of the neck • Larvae migrate thru skin and cause dermatitis • Insects implicated in spread – flies • Dx by response to treatment • Tx ivermectin, repeating dose 3 wks • Death of microfilariae cause itching, use steroids

42. Onchocerciasis

43. Rain Scald / Rain Rot • Fungal and bacterial components • Organisms trapped in hair – reproduce • Direct contact, objects • Clin. Signs: matted hair, alopecia, crusting • White legs • Nonpruritic, but may be painful • Bathe: iodine, chlorhex, antifungal • Prevented with daily grooming and attention • Infectious – disinfect grooming materials and tack • More attention during winter month, thaw, spring

44. Ringworm • Zoonotic! • Fungi: trichophyton and microsporum • Direct contact, objects • Multifocal lesions, alopecia • Classic round shape, may or may not itch • Fungal culture • Self-limiting (in horses), disinfect tack, etc. • Topical antifungals, miconazole, iodine, chlorhex, griseofulvin

45. Sarcoids • Most common skin tumor in horses • Single tumor or multiple nodules • Biopsy, surgical excision • Injection of chemo agents into tumor • cryosurgery

46. Proud Flesh • Red, protruding cauliflower-like flesh over wound that bleed easily, distal limbs • Scar tissue growing out of control (exuberant granulation tissue) • Meat tenderizer, enzyme sprays • Removal – no sensory nerve endings in scar tissue • Avoid caustic substances that delay healing • Prevent with wraps, chlorhex/steroid oint • Furacin oint may cause an increase in development

47. Proud Flesh

48. Warts (Papillomatosis) • Young horses <3 yr • Papillomavirus • Direct contact, objects • Wart-like growths – muzzle, lips • Self-limiting • Separation to prevent spread to other horses

49. Wounds • External trauma • Specific tx depending on source • Suture, staple • Puncture wounds • Abx therapy • Tetanus booster • Use tetanus toxoid, not antitoxin in vaccinated horses – severe anaphylactic reactions reported

50. Sheep and Goats Contagious Ecthyma • AKA sore mouth, orf, scabby mouth • Parapoxvirus – epithelial tissue • Active in environ. for months if not yrs • Direct contact, objects • Papules, pustules, vesicles • Thick crust around mouth – spread to oral cavity, eyelids, feet, udder • Typ. resolves in 2 wks, unless lesions are severe – supportive care • More severe in goats than sheep • Biopsy • Zoonotic