Color Dilution Alopecia (CDA) is a rare disease that affects dogs with dilute coat color (blue, fawn, etc.). This disease results from abnormal distribution of melanin granules and formation of macromelanosomes in the hair shaft. This weakens hair and causes them to break especially along the dorsum. Learn how to recognize this disease, useful diagnostics and treatment options on this week's episode of The Derm Vet podcast.
TIMESTAMPS Intro 00:00 What Is Color-Dilution Alopecia? 01:06 Main Symptoms Of Color-Dilution Alopecia 02:02 The Tricky Part Of Color-Dilution Alopecia 02:43 The Disease Process 04:04 The Complications 07:19 Treatment Options 09:36 Educating Pet Owners 12:44 Outro 13:48
Color Dilution Alopecia (CDA) is a rare disease that affects dogs with dilute coat color (blue, fawn, etc.). This disease results from abnormal distribution of melanin granules and formation of macromelanosomes in the hair shaft. This weakens hair and causes them to break especially along the dorsum. Learn how to recognize this disease, useful diagnostics and treatment options on this week's episode of The Derm Vet podcast.
TIMESTAMPS Intro 00:00 What Is Color-Dilution Alopecia? 01:06 Main Symptoms Of Color-Dilution Alopecia 02:02 The Tricky Part Of Color-Dilution Alopecia 02:43 The Disease Process 04:04 The Complications 07:19 Treatment Options 09:36 Educating Pet Owners 12:44 Outro 13:48
Well, welcome to another episode of the Dermvet podcast. I wanted to go over a disease of something that I don't see a ton of, but I recently saw a case of and I thought it could be a really good refresher on a certain alopeicic disease that can get mistaken for things like allergies, which makes sense in some of the aspects of this process. But there are some clinical signs that can give you a good indication you are dealing with this disease process itself. And then that disease is going to be color delusion alopecia. So color delusion alopecia can be a bit tricky because ultimately some of these dogs are pretty paritic and itchy because of the secondary infection. So what is color delusion alopecia and how I expect to see that in a case that I am evaluating in the clinic? So color delusion alopecia is exactly as it sounds, a disease that we tend to see and color delute pets. So if you think of some of our blue diluents of a case for a coat, some of our silver, anything that's more dilute, even some of these like lighter colored, like the light orange colors, anything where their particular hair coat color is a more dilute variant. It doesn't mean they have color delusion alopecia, but they could be at risk of it. It's kind of a tail-tell sign when you see a dog primarily, or we see this disease, a dog with this color of a coat in certain clinical signs that you should be thinking color delusion alopecia. What are those clinical signs? The main thing we will see in dogs that have color delusion alopecia is they will have kind of a really patchy alopecia or hepotrachotic coat mostly on the dorsum. They tend to be dogs that are younger, so puppies to maybe young adulthood, they'll start just getting a thinner coat on the dorsum itself. They can get it in other areas too, but the dorsal area is the most common area we see. So a blue silver, fawn colored pet that's having hair loss along the dorsum and they're younger. If you describe that to me, I would say color delusion alopecia until proven otherwise, but what's tricky about these pets? What can be tricky is that they're itchy, so because we see this history of them becoming paritic, which the disease itself is not really itchy, but because they are so predisposed to pyaderma, they become paritic from that. So we'll see young dogs coming in for itchiness, of course, the dorsal area of the trunk is something we can see affected with allergies. A lot of times when they go on medications to treat the allergic symptoms, whether it's apaquil or steroids are often going on anti-infectives if there's a secondary infection because of the crusting, the hair loss they are experiencing, they'll go on infection control so their itch will get better. So it really feels like their itch will get better, their young dog makes sense. So we see these delupereats come in and again, usually see it distributed along the back portion of the body. And I will make sure to share some pictures on my social media just so you guys can clinically see those. So we'll see kind of that area on the dorsum that is thin, haired. They tend to be kind of scaling crusty again because one, they're infected, but even if they're non-infected, their skin doesn't tend to look perfect because ultimately they still have skin barrier defects, just like we'd expect in a dog who has allergies, they have skin barrier defects. But what is this disease process itself? Why don't we see every blue or silver dog come in having color delusional apisha? We certainly see blue dobes, silver labs, silver pitties that come in without having the actual alopecia symptoms themselves. Well, what can happen with some of these dilute colors is we obviously expect that their pigment, their melanin within the hair itself is going to be distributed differently to give that blue color. But what can happen is we can get clumping in something called macromalanusomes. So essentially they have a genetic defect that causes them to distribute the pigment in their hairs when they have this disease process. They'll get that unusual hair color, but not just that getting that blue or fawn color, that melanin will clump and will cause a lot of different changes to the hair, the hair itself. You actually do a tricograeum, which would be plucking the hairs. Sometimes you can see just abnormal clumping within that hair follicle versus, or sorry, that hair cortex, the hair shaft itself versus what you'd see in a normal dog would be very organized. It's going to be a lot of disorganization. And then that clumping, those macromalanusomes can start damaging the cortex. And these dogs themselves when they have that alopecia region, especially on their dorsum, it's really due to the damage of the hair they break, they're really weak. And it's really hard because of that clumping within that hair itself, the fur itself, to really prevent that from happening. So we get excessive pigment clumping. You get breakage of the hair shops. And then that in turn creates abnormal and stunted hair growth. We also end up with a lot of secondary infections additionally. So if you see a dog who comes in, they have a very dilute coat plus that dorsal aspect, they're young, that dorsal aspect looks really alopeasheck. They're getting scaling, crusting, sometimes they get combatone, things like that. Then I would want you to be considering something like other dilution alopecia. What's tricky is we can see dogs who have multiple diseases. So I just named some breeds that we also see a lot for, you know, adipi. So we see a lot of pitties for adipi, we see dobes for adipi, labs for adipi, and there's other different breeds that can get this disease too. But I have had plenty of dogs who have color dilution alopecia, but they also have atopic dermatitis or food allergy or a mix of those so that also can be really complicated because if they are additionally besides having that hair loss on the back of their, their trunk, they're also licking their paws and chewing their paws and getting ear infections, you're probably dealing with multiple issues. You can get other areas of the body affected, but I don't usually suspect to see that they're going to lick their paws to their paws, you know, break out on their ventral abdomen where they don't have much hair anywhere, really break out with things like ear infections. We predominantly see it kind of on that trunkal area. So if you have multiple diseases, then we just need to make sure we're addressing both these separately. What are some of the complications that we can see with this disease process? Well, one of the complications is obviously infection as we talked about. I've seen occasionally malnsezia dermatitis with this disease, but I would say predominantly I see a secondary pyiderma that is frustrating because it can kind of keep happening and be recurrent. The other complication of this disease, excuse me, is that they do not tend to fully resolve. So it is by nature more a cosmetic disease, except for the secondary infections. That's obviously really bothersome for the pet and the owner, but that secondary, sorry, the appearance of them kind of having that alopecia on their back. That is something that ultimately is probably never going to be totally normal. So the owners also have to accept that, which is really difficult when we have some of these diseases with hair loss that we cannot fully reverse. So think about some of the frustrating diseases, like the follicular dysplasia, even some of the hormonal diseases like the dreaded alopecia X or whatever you want to call it. There are certain diseases we deal with where even if they're quote unquote cosmetic, which I always have a bit of a hard time when we call things cosmetic if they can lead to other issues like secondary, secondary infections or if it can lead to things like skin barrier abnormalities, but cosmetic disease in itself, meaning that, you know, besides kind of restoring the skin and preventing infections, they're just going to have not as much hair there can still be really emotional and frustrating for the owner because they didn't expect to get a dog that the rest of that dog's life. And remember a lot of these doctors are quite young when they're diagnosed that when they walk it down the street, people are going to wonder why it doesn't have much hair or with scaling crusty, do they have mean? Is that owner taking care of the pet? So that's something that we really have to consider that this is still something that really affects the owners. It can affect their, you know, the what they expected with their pet, their quality of life as far as being able to able to visually show their pet. So something that we definitely want to think about because we can restore that skin barrier, we can do our best to try to prevent things like infections or current issues, but we're probably never going to fully normalize that hair coat. What are some of the treatment options we can consider? There is no cure for this disease. There's not many cures for things in dermatology unless you have like, skabies or dermatitis. But the, the really the main treatment is trying our best to try different tools to minimize those pet dermas. So we want to utilize things that are going to help with secondary infections. You know, certainly these are some of those dogs that have to end up on more chronic things like car accident based products if they are really susceptible to breaking out with infection because there's not really a systemic therapy. You can try things like melatonin. It's not really going to do anything in this particular disease because it is that dilute hair itself and not so much the melatonin receptors on the hair follicle, but it's that dilute coat and those abnormal aggregations of those pigments itself. So melatonin's safe, but probably not going to do a whole lot in most of these cases. So then you're really trying to do things to help with secondary infection. So you can do more mild things like topicals, I have salicylic acid in them, sometimes solfers. I've seen people use benzoyl peroxide based products. The idea behind that being that it flushes out the follicle and has some antiseptic properties. I think in some cases those can work well, but benzoyl peroxide is also more drying if you've ever used it on your own skin. So sometimes I have cases where it seems to dry out their skin more and we will switch to something like a Duke, so as three, you know, PIO, if they are susceptible to infection because then we're not only treating the infection with chlorhexidine, but utilizing something that has oveatrium in it, which is to restore their skin barrier. There's other things you can use too. Dermacent has some topical products to restore the skin barrier. They also have things that help with things like the PIO line that can have more natural herbal things in it that can help also be defensive again secondary infections. I just find a lot of times you have to kind of trial and error some things that work for that particular pet. What is treating the infection? What is preventing the infection? What do we need to do long term? And then what's also helping to restore that skin barrier? So whether that is, you know, trying to do things like supplementations with fish oils or certain skin barrier supplementations that are out there, some of the diets that are out there to help restore that skin barrier. It's not going to treat the disease itself, but if we can try to nutritionally help the skin, hopefully that will benefit us in some degree. You also want to make sure that the owner is really cautious of things like harsh grooming or being really rough with that. So these are not dogs you want like metal combs used on the back end. I'm probably just going to ask for some irritation and a reaction to that. Really gentle grooming going to the direction of the hair. This is not a disease where you kind of want to be rubbing them multiple directions because those hairs are fur are already susceptible to breakage. And if you keep breaking those hairs, you potentially could still aggravate things to get to the point of causing the recurrent infections, which is certainly not something we want to do with this disease process. And then we just have to take the time to educate owners about this disease. Again, you these are ones that really clinically we can tell pretty well. By looking at them, if you are going to talk to them about diagnostics, kind of the main things you can do is the trigogram we talked about. If you collect a trigogram, which is like plucking hairs, you can look for things like abnormal clumpings of melanin granules, if they're kind of breaking the hairs, destroying that cortex of the hair itself. And then in certain cases, if you're not sure, you think multiple things are going on, it certainly wouldn't be wrong to biopsy these pets to rule out maybe other things. If I see a dog coming in with this, I have a really, you know, educational conversation with the owner about the fact that this is a disease that we'll have to manage. We're never going to have perfect. We're just going to do our best to utilize some supplemental things, some topical things to prevent infections, which hopefully will keep them comfortable and then restore that skin barrier. But they kind of have to be accepting of the fact that that hair will never fully grow in. And so these are some big things we want to think about. This is a disease that hopefully clinically as you get more comfortable, you can start to pick up on again, young dog coming in with that dilute hair coat around the door. Some I would automatically start thinking about things and they have that that presentation we talked about. I would automatically start thinking about those things like color delusional apesia. Of course, there can be wacky cases. So if it makes sense to run some lab work to rule out things like hypothyroidism, which could also affect their hair, coat and lead to them to secondary infections, occasionally get younger dogs that have that that would not be wrong. But hopefully as you game or experience and you start to pick up on some of these cues, you can feel more confident in this diagnosis and then set up a good treatment plan, but also set up your owner's expectations long term to manage a disease and have realistic expectations of management of a disease like color delusion alopecia.[BLANK_AUDIO]