The joys of dermatology

Well it's been an erythematous, exudative and cerumenous week on derm. Translation: Redness, oozy ickiness and earwax!

We've had some very interesting patients so far this week and I've learned that derm is often like an episode of House.  We have to go through the patient's entire history from when the dermatological problem began including every attempted treatment and it's effect on the issue, any possible exacerbating factors, any other health issues and the corresponding medications that may be on board and the patient's current state.  We also have to consider the owner's compliance when determining if previous treatments have been effective and if the possible treatments we are suggesting will be carried out effectively by the owner.  Once we have a list of potential diagnoses, we try to start crossing them off the list by doing all the cytologies and scrapes that I mentioned in my previous post. If we don't find anything there we have to consider other things like food allergies, environmental allergies or flea allergies.  It's always an adventure!

One of our patients yesterday presented with chronic otitis externa (external ear infection).  Aside from her ears, she had some irritated areas on her abdomen and between her toes (dogs lick the spaces between their toes excessively when they are itchy!).  In addition to the otitis, this kid (I will call her Bertha) had previously been diagnosed with hypothyroidism, Addison's disease and had recently had an issue with pancreatitis potentially due to the ridiculous amount of steroids she had been on for a looooong time. On her laundry list of medications along with Prednisone (steroid) was Rimadyl (non-steroidal anti-inflammatory).  Traditionally, it's a major no-no to give an animal both of these because it wreaks havoc on their GI system (ulcers, bleeding, general ickiness), but Bertha was on both of those plus quite a few others.  However, our main concern was the otitis.  Given her circumstances, we took samples to look for the usual bacteria, yeast and parasites.  We didn't find anything fun or exciting despite her ears being disgusting and full of debris and discharge.  Some ear cleaning solution was put into her ears, after we took samples, and was allowed to sit in there for a bit to break up the cerumen (earwax, remember?) before we cleaned all the ickiness out.
She is an older dog so we also had to consider neoplasia (i.e. a mass in her ear canal) as well as other growths like a cyst or polyp. We didn't find anything in the outer canal using the otoscope but the owner OK'd us to run a CT scan.  On the CT, it's easy to see the entire ear canal and the bullae which is the large opening in the middle ear (past the eardrum).  Fortunately for Bertha, we did not find anything of concern on the CT.  We went back to do a more in depth cleaning of her ears while she was still sedated.  You would not believe the amount of junk that came out of there.  Once we had a clear path, we used the video otoscope to see down into her ear canal to the eardrum (and take some sweet pictures!).  We could tell that the more problematic ear definitely had a thickened and unhealthy eardrum (tympanum/tympanic membrane), but it was still intact (yay!). The other tympanum looked healthy and happy.  So basically, all we could do for this dog was give the owner some ear drops to keep the ears clean and free of debris and give her some topical treatment for the itchy toe problem.

Today we had a pit bull (well-known for having dermatological issues) with MAJOR pruritis all over and clear signs of chronic itching and irritation.  The most glaring issue was the dog's vulva (maybe I should prepare everyone, this is gonna get graphic).  According to the owner, the dog had such intense pruritis in that whole area that she would literally go outside and drag her lady parts along the concrete seeking relief.  Because of this, her vulvar area was hyperpigmented (black, when it should have been pink), hyperplastic (enlarged, it looked like she had boy parts) and super sensitive.  In addition to this, the area between her toes was erythematous and swollen, her belly was red, the area around her eyes and ears was swollen and she had several areas where her fur was thinning due to her scratching.  So so sad to see a dog like this.  The worst part is that her current state was an improvement over how she presented on her initial visit.  We took all kinds of samples from all over the place and we really thought we would find some crazy stuff.  We essentially found nothing. No crazy parasites, no overwhelming bacterial or yeast infection, nothing.  According to her history, the dog had previously been on high doses of steroids for a long time which had caused her to gain A LOT of weight and lead to the development of congestive heart failure.  Also, because she was on the steroids for so long and was not weaned off of them properly, she had issues with iatrogenic Cushing's disease which is basically when there is too much cortisol in the blood.  Iatrogenic simply means "caused by treatment".  So by giving steroids long term we pump the body full of cortisol to the point that it stops producing it on it's own and kind of forgets to do it when we abruptly take away the steroids. Understandably, the owner was hesitant to put the dog back on anything involving steroids.  This makes it a little difficult from the dermatology end of things, because it is common in cases of severe pruritis to prescribe steroids to get it under control.  The steroids work to reduce inflammation and control the itchiness to a manageable level.  So we went another route to try to help this dog.  First, the dog will be bathed weekly with a shampoo that contains an anti-histamine and an anti-fungal agent.  That is allowed to sit on the skin for 10 minutes before being washed off.  Right after that, the dog is sponged down with a Lime-Sulfur dip which is often helpful in treating a wide variety of dermatologic issues.  Then, for her vulvar area, she was given Silver Sulfadiazine cream.  SSD is a topical antibiotic that is often used on burns because of it's ability to soothe irritated skin.  We suggested that the owner put a diaper on the dog after applying the SSD to ensure that it was not licked or rubbed off of the area.  Lastly, the dog is being started on a food trial to attempt to eliminate any food allergies.  She was given a hypoallergenic food and will not receive any other food or treats of any kind during the food trial.  Usually, a food trial lasts at least 8 weeks. It can go longer depending on the severity of the dermatitis and various other factors.  Hopefully, some of these things help this dog and she gets some relief.  Despite her obvious discomfort she was such a sweetheart when we were getting samples and doing a physical exam. Poor kid!!

That's it for today. No doubt, there will be more dermatological excitement tomorrow!