Chronic and recurrent otitis is Management of Otitis frustrating! • Otitis externa is the most common ear disease in the cat and dog • Reported incidence is 10-20% in the dog Lindsay McKay, DVM, DACVD and 2-10% in the cat [email protected] • It is a common reason for referral to VCA Arboretum View Animal Hospital dermatology specialists and very common clinical problem for general practitioners 1- Primary causes- directly Breaking down the problem induce otic inflammation • ALLERGIES (atopy and food allergies) • Step 1- Identify the primary cause of otitis • Parasites (Otodectes cyanotis, Demodicosis) • Step 2- Assess for predisposing factors of • Masses (tumors and polyps) otitis • Foreign bodies (ex plant awns, hair, • Step 3- Treat the secondary infections ceruminoliths, hardened medications) • Step 4- Identify the perpetuating factors of • Disorders of keratinization (hypothyroidism, otitis primary seborrhea, sebaceous adenitis) • Immune mediated disease (pemphigus, juvenile cellulitis, vasculitis) What are most common causes of 2- Predisposing factors of ear disease recurrent otitis…. • These factors facilitate inflammation by changing • Allergic disease in the dog- over 40% cases environment of the ear! in one study • Ear conformation- stenotic • Polyps and ear mites in the cat canals, hair in canals, pendulous ears • Excessive moisture or cerumen production • Treatment effects- irritation from meds/contact allergy or trauma from cleaning 1 3- Secondary bacterial and/or 4- Perpetuating factors- prevent yeast infections the resolution of otitis • Epithelial thickening, • Address with ear glandular hypertrophy cleaning, topical • Dermal fibrosis, antimicrobial agents, cartilage mineralization most often topical steroids and in some • Stenosis of lumen cases systemic anti- • OTITIS MEDIA infectives and systemic steroids Otitis Externa Otitis Media Clinical Signs Physical Exam Findings • Head shaking • +/- Pinnal erythema and hair loss • Scratching/rubbing at ears • Erythema, swelling and • Otitis media- inflammation of the middle ear • Odor debris present in the external • Pain ear canal • Often an extension of otitis externa through a • Itchiness in other • +/- Ceruminous gland ruptured tympanic membrane locations hyperplasia • Ear drum appears normal and • May also occur from polyps or neoplasia intact within the middle ear • +/- Concurrent skin disease Clinical signs of Otitis media Otitis media • In dogs with recurrent ear infections for 6 Clinical Signs Physical Exam Findings months or longer, up to 82% had • Elevated third eyelid • Ruptured or intact tympanic 1 concurrent otitis media • Drooping lip on one side membrane • Intact membrane can be • AND in 71% of these cases of otitis media, • Parasympathetic nose- 1 bulging, hemorrhagic, the ear drum was intact at time of diagnosis unilateral hyperkeratosis discolored and exudate may • Treatment of otitis media often involves • Pain, odor, head shaking be visible greater than 6 weeks of systemic antibiotics (any and all signs of otitis • Neurologic abnormalities- externa) Horner’s syndrome, facial • Deep ear flush under general anesthesia • Balance issues, head tilt (if nerve paralysis greatly aids therapy of otitis media concurrent otitis interna) • Neuro signs of otitis interna- peripheral vestibular 1. Saridomichelakis MN et al. Aetiology of canine otitis externa: a retrospective study • Hearing loss disease, and deafness of 100 cases. Vet Derm 2007; 18: 341-347 2 Otoscopy Otoscopy • Evaluate both ears Normal – Use separate cone for each ear – Ear pinnae – Vertical ear canal • Horizontal and vertical canals – Horizontal ear canal – Sebaceous glands- associated with HF, density greatest proximally – “Noxon’s Ridge” – Ceruminous glands- greatest density deep in ear canal – Tympanic membrane – Hair follicles- decrease in number distal to proximal (outside to inside) – There are a few fine hairs at entrance of external Noxon’s Ridge acoustic meatus, serve as helpful landmark for locating the eardrum A normal ear is self cleaning! Otoscopy Normal • Epithelial migration- epithelium in the ear canal grows outward from the tympanic membrane toward opening of the external • Horizontal and vertical canals ear canal – Light pink – Smooth • Epithelial cells carry debris with them – Minimal exudates • When this is disrupted, we can see ceruminoliths – Vertical canal 5-10 mm diameter where it meets • Ear canal masses also interrupt self cleaning horizontal canal Otoscopy Otoscopy Abnormal Normal • Glandular hyperplasia – Acute: • Tympanic membrane • Enlargement and – Pars flaccida hypersecretion • Upper quadrant – Chronic: • Elongated, full of colloidal • Pink with small vessels cellular debris • Little secretory activity, duct openings plugged • Loosely attached 3 Otoscopy Normal Canine Otoscopy Normal Feline • Tympanic membrane • Manubrium of malleus – Pars tensa is straighter in cats • Pearl-gray • Thin • Radiating bands • Tough – Manubrium of malleus (stria mallearis is outline of manubrium of malleus that can be visualized Curve points towards through membrane) the nose! Otoscopy Otoscopy Abnormal Abnormal • Ceruminolith • Mass behind tympanic • Mass membrane • Foreign Body • Abnormal tympanic membrane • Inflammation • Ruptured tympanic • Excess exudates membrane Tympanic Cavity Tympanic Cavity DOG CAT DOG CAT • Divided into 2 cavities by an • Consists of small almost complete bony septum epitympanic recess and • Larger cavity is the large ventral bulla ventromedial compartment • There is incomplete bony • To gain access you would need septum (Rosychuk’s Ridge) to break down this bony that allows communication septum = likely nerve between dorsal and ventral damage!! cavities • Leave that to surgeons! Refer for VBO if imaging shows mass or exudate there! 4 Therapy of otitis externa Therapy of otitis media 1- Keep ear canal clean 1- Keep ear canal clean 2- Topical and/or systemic anti-inflammatory therapy 2- Topical anti-inflammatory therapy 3- Topical antibiotics/ antimicrobials 3- Topical antibiotics/ antimicrobials 4- Systemic antibiotics and/or antifungals 4- TREAT THE UNDERLYING CAUSE 5- Deep ear flush and otoscopy under general 5- Monitor response to therapy with recheck anesthesia exams and otic cytology 6- TREAT THE UNDERLYING CAUSE 7- Monitor response to therapy with recheck exams and otic cytology 1- Keep the ear clean 1- Keep the ear clean • Ear cleanser options: • Removes the nidus (ex. cerumen) of infection o Epiotic Advanced- creates acidified ear • Removes bacterial and inflammatory debris canal • Allows antimicrobials to penetrate the entire o Douxo Micellar or ear canal Cerumene- • Prevents purulent debris from inactivating ceruminolytics antimicrobial agents, especially important for • Clean every 1-2 days aminoglycosides Ear cleaning instructions for Following cleaning, presoak with owners- the gauze method Triz EDTA • 3 by 3 gauze • Indicated in bacterial • Wet gauze with cleaner or infections, especially when pour cleaner into canal rod shaped bacteria such as • Gently massage gauze into Pseudomonas present ear canals • Presoak the canal with Tris- • It wicks up debris and EDTA product prior to cleans ear gently medicating • Repeat until clean gauze • Do not wipe clean emerges • Tends to be very well • Done on a daily basis, prior tolerated! to medicating ear 5 2- Topical and Systemic Steroids 3- Topical therapy yeast otitis • Unless medically contra-indicated, always • Topical antifungals- miconazole, treat otitis externa with topical steroids clotrimazole, ketoconazole • In preparation for deep ear flush and/or • Can be used alone, or in conjunction with painful swollen ears- add 2-3 week course steroids of oral glucocorticoids • Treat over 3-4 weeks with topical therapy • Steroids decrease inflammation and • In otitis externa/ media, treat until external production of cerumen, reduce swelling and canal cytology is negative stenosis of canal, and make pets less painful 3- Topical therapy- Antifungal topical recipes bacterial otitis • Miconazole 2% (1.5 to 3ml) with Synotic • First time infections- cocci- gentamicin, (8ml bottle) florfenicol, Polymixin B or orbifloxacin are • Miconazole 2% (20 ml) with good choices Dexamethasone 2 mg/ml (5-10ml) • First time infections- cocci, rods- gentamicin, • Clotrimazole can be substituted enrofloxacin, orbifloxacin and Polymixin B • Treat for 3-4 week period • Important to recheck prior to end of therapy to ensure that infection has resolved The role of Pseudomonas in canine otitis Clinical Signs- Pseudomonas otitis • Pseudomonas aeruginosa- aerobic, gram • Head shaking or negative rod bacteria scratching • Associated with chronic otitis externa and • Purulent exudate media in the dog • Malodor • Swelling, • Isolated in up to 20% of dogs with otitis inflammation and pain • Rapidly develops multi-drug resistance • Ulceration • OTITIS MEDIA 6 Recognize biofilm when you see it Therapy of Pseudomonas otitis • Ear cytology from ear chronically infected with 1- Keep ear canal clean Pseudomonas aeruginosa 2- Topical antibiotics/ antimicrobials toxic neutrophils, numerous rod bacteria, some within colonies 3- Systemic antibiotics in the dark purple material 4- Deep ear flush and otoscopy under general which is biofilm anesthesia • Culture and sensitivity is indicated for most cases where 5- Topical and/or systemic anti-inflammatory rods are seen and especially if therapy biofilm noted • Start preparing owner for deep 6- TREAT THE UNDERLYING CAUSE ear cleaning Pseudomonas ear infection Antibiotics with potential