Otitis Flashcards
Indications
Microbial overgrowth
Immunomodulation
Pruritus
Skin barrier production
Hormone Management
Nutrition deficiency
Parasitic management
Microbial infection
Confirm presence of infection (cytology)
Determine level of infection
-Surface/superficial/deep
Choose therapy
Management to prevent recurrence
Surface pyotraumatic dermatitis
Clip (norm sedation)
Clean
Daily topical antiseptic/antimicrobial
Anti-inflammatory - preds
Analgesia - paracetamol
Manage primary disease
Intertrigo (skin fold dermatitis)
As for pyotraumatic dermatitis
Look for underlying cause
Consider Sx
Can progress to deep infections
Pyoderma/ folliculitis
Topical antiseptics (2-3/wk)
Systemic AM not normally needed unless widespread
Manage underlying cause
Deep pyoderma
Local- topical
Widespread - systemic AM
Topical antiseptic
No other choice for multi-resistant infections
Sole therapy for surface Dz-
-otitis externa, surface pyo
Chlorhexidine
Duration of Tx
Superficial
-2-3wks clinical and cytological cure
Deep
-4+wks palpable, clinical and cytological cure
Otitis general
Inflammation of ear canal
Otitis externa - external ear canal
Otitismedia - middle ear
Otitis interna - inner ear
Pinna can also be affected
Common 1st opinion problem
Otic anatomy
Facial nerve
Tympanic bulla
Tympanic membrane
- Pars flaccida, Stria mallearis, Pars tensa
Otic histology
Ear canal lined with modified skin
-small hair, ceruminous glands, sebaceous glands
Middle ear lined by modified respiratory epithelium
-simple squamous, few ciliated cells, goblet cells
Otic physiology
Self cleaning
-Cerumen- catches material and has AM peptides and Igs
-Epithelial migration-carry cerumen out of canal
Mid ear clean
-goblet mucus drained via eustachian tubes (nasopharynx)
Flora
-G+ve cocci
-Malassezia
Pathogenesis
1°- Otodectes, demodex, allergy, FB
(Foreign body, Allery, Bug) (FAB)
Cats 1°-viral (FCV), para, allergy
Allergic otitis
OE- manifestation of allerigc Dz
Pruritus, normally bilateral
FB otitis
Unilateral
Grass seed
Acute and severe onset
Painful
Otodectes cynotis
Dark coffe colour wax
Hyper sensitivity reaction to mites
Pruritis
Ectopic dz
Mites are photophobic (indirect smear in paraffin)
Predisposition
Hairy canal (poodle)
Narrow canal (shar pei)
Waxy canals (cockers)
Pendulous pinnae
Water (swimmers)
Hot and humid
Neoplasia and polyps (also 1° Dz)
Progressive pathological changes
Failure of epithelial migration
Progressive epithelial hyperplasia, oedema, fibrosis
Glandular dilation and hyperplasia
Canal stenosis
Rupture of tympanum
Calcification of pericartilaginous tissue
Osteomyelitis
Para-aural abscessation
Otitis Dx
Check both ears
Assess and palpate pinnae and external ear canal
Otoscopy (sedation if painful)
Imaging - if OM/ OI
-radiography, CT, MRI
CS Otitis externa
Otic pruritis - scratching, head shake
Pain
Discharge (otorrhea), malodour
Deafness
Pinna- erythema, lichenification
Otoscopy- epithelial erythema, ulceration
CS progression
Secondary causes & perpetuating factors develop due to 1°
Allergic otitis>Malassezia overgrowth
Change in Env. due to inflammation and high humidit
Chr Pseudomonas OE progress to OM
Ear cleaning
Most otitis cases can be help with cleaning
Removal of debris
Visualisation of TM
Enhance topical therapies
Ac, no pain, minimal debris
-conscious, proprietary cleaner
Chr, copious discharge
-GA, saline lavage (till TM seen)
-Analgesia (paracetamol), Preflush preds
Anti inflammatory Tx
Resolve progressive pathological changes
Epithelial and glandular hyperplasia and stenosis
Glucocorticoids
-anti-pruritic, less secretion, systemic/ topical prednisolone
Long term- ciclosporin
Cytology
Cheap, low risk
Dx of infection
Differentiate sterile/ infectious otitis
Informs empirical topical therapy
Assess therapy response
Indirect smear with cotton bud
NO overgrowth> Anflamms
Yeast> topical antiseptic/ fungal
Bacteria> topical antiseptic/ antibiotic
