Presenter: Dr Klaus E. Loft DVM of Angell Animal Medical Center (MSPCA), Boston USA.
Dr. Loft has published articles and lectured both in Scandinavia and the United States, his special interests are feline dermatology and chronic ear disease.
With grass seed season upon us, cases of acute onset otitis externa will start to flood through the door and most of the time the problem is easily solved by removal of the offending foreign body. Unfortunately treating cases of chronic or recurring ear disease is not always that simple, however after watching this veterinary webinar led by Dr Klaus E. Loft DVM covering ‘Otology in the Dog and Cat’ it may have just got a little easier.
Dr Loft firstly wanted to emphasize that a patient showing ear disease is always a dermatology case until proven otherwise and a full case history is absolutely key in deciphering whether these patients have ever suffered any previous dermatological episodes. Dr Loft also encouraged us to approach the management of these cases by taking into consideration the three ‘P’s affecting ear disease, ‘predisposing’ factors, ‘primary factors’ and ‘perpetuating factors.
Predisposing factors are conditions that facilitate and increase the risk of inflammation within the ear canal. Anatomy and confirmation fall under this category with breeds like the Sharpei suffering from marked stenosis of the ear canals. Other conditions include obstructive disease such as neoplasia and keratinisation defects such as sebaceous adenitis.
Primary factors are conditions which initiate inflammation of the ear canal. Cutaneous adverse food reaction and atopic dermatitis fall under this category. Usually these cases have a history of multiple recurring episodes of otitis externa and most will have bilateral disease. According to Dr Loft there is an 80% incidence of otitis externa in cases of cutaneous adverse food reaction and is seen as a single entity with no other clinical signs in 24% of these cases. In comparison, there is a 50-80% incidence of otitis externa in dogs suffering from atopy and is only seen as a single entity in 5-10% of these cases.
Perpetuating factors maintain or worsen inflammation within the ear canal of which over treatment and under treatment are two of the main culprits. Over treatment such as over use of an ear cleaner can lead to an excess of moisture within the ear canal and could cause mechanical trauma. Under treatment however is the biggest reason for failure as drugs may not have been administered for long enough and in many cases we may just be under dosing. Dr Loft explained the total length of an ear canal can be up to 5 – 7.5 cms in length especially in breeds such as the Basset hound. This is a lot of ‘skin’ that we need to treat and the standard 4-5 drops administered topically may just not be enough.
Dr Loft went on to discuss the importance of cytology in all these cases and judged this a ‘must do’ technique in every case that walks through the door before any manipulation of the ear canal takes place. He also discussed the use of topical and systemic medications in managing these cases indicating how much topical medication he would administer for different sized animals and also discussed his use of systemic medication in chronic cases of otitis externa and otitis media.
Dr Loft’s veterinary webinar was an excellent insight into how we can best manage ear disease by considering the broader issues around this condition. This was a thought provoking webinar organised by ‘The Webinar Vet’ which looked at ear disease from a slightly different angle compared to other forms of CPD I have encountered on this subject matter and is in my opinion well worth an hour of your time.
The Stethoscope (MRCVS)