Nasodigital Hyperkeratosis in Dogs

Nasodigital hyperkeratosis can affect any dog breed of any age, sex, and genetic predisposition.  If your dog is young to middle-age and has this condition, there may be an underlying cause to the development of the excess keratin.  If your dog is older, it may simply be age related.  Many times the condition can be diagnosed by appearance alone, but some cases require further diagnostic testing.  There is no cure for this condition but you, as the owner, can manage it to keep your dog comfortable.

Nasodigital hyperkeratosis can be characterized as an overproduction of keratin on your dog’s nose and/ or feet.  If the tip of your dog’s nose or paw pads look dried out and crusty, you should take him to his veterinarian for an evaluation.

Symptoms of this condition include:

• Excess amounts of horny tissue on nose
• Excess amounts of horny tissue on the paw pads
• Hyperkeratinization can appear grooved, rigid or feathered 
• The dorsum region of the nose becomes hard, dry and rough
• Ulcers on the dry epidermal tissue 
• Erosions on the dry epidermal tissue
• Fissures on the dry epidermal tissue

Types

In a normal healthy dog, his paw pads and nose have a fine appearance with no adherent keratin; it has a smooth papillated appearance.  As the dog eats, drinks, and walks, it removes the keratin from the areas as it reaches the surface.  This prevents the buildup of keratin you see in this condition.  In dogs where their facial architecture is abnormal, such as a Boxer, English Bulldog or Boston Terrier, the regions of their nose that would be expected to touch the bowl do not.  This allows the buildup of keratin since it does not touch the bowl to allow for natural sloughing of the keratin.  Same for the feet, if the dog has a deformity that prevents the paw pad from touching the ground to allow for natural wear, the keratin will build up on the paw pads as well.

Nasodigital hyperkeratosis can be caused by a variety of conditions.  It can be a congenitohereditary disorder that may show up at some point of your dog’s life.  This condition can be immune mediated, can be caused by an infectious disease, from a metabolic condition, inherited, neoplastic, or even idiopathic.  Illnesses that can cause this condition as a result of the ailment can include canine distemper, systemic lupus erythematosus, and as a drug reaction to just name a few.

When you arrive at the veterinarian’s office, she will start her diagnostic process by collecting a verbal history from you.  For example, she will want to know when you first noticed the development of your dog’s symptoms, how fast the condition has been progressing, and if it seems to impair his daily routine.  She will then proceed with performing a full physical exam.  While it may be obvious the extra keratinization is on his nose and feet, she will want to check him over entirely for other symptoms that could be indicative of the cause of his condition.  

An older dog with no other skin conditions occurring simultaneously can be diagnosed with this condition often by appearance alone.  This is easily confirmed if the dog does not have any other systemic problems.  Also, if he has an anatomic abnormality that will allow for this condition to develop, it will assist with a diagnosis based on clinical symptoms.    

If your dog is younger to middle aged, further diagnostic testing will be recommended to properly diagnose his condition.  Other illnesses that can cause this condition as a secondary development must be considered and ruled out.  To confirm the diagnosis, your veterinarian may recommend a biopsy.  This would involve taking a sample of the affected area and examining it under the microscope.  Dogs with this condition have a specific look to the cells that can confirm the condition.

Blood work and serology testing is recommended to rule out underlying causes of this condition.  A complete blood count (CBC) and chemistry panel will provide the vet with general information on your pet’s internal organ function.  As for serology testing, she will want to rule out possible viruses that can lead to the nasodigital hyperkeratosis.

Treatment for this condition is lifelong as the formation of keratin cannot be stopped.  The idea of treatment is to soften and remove the excess buildup of keratin.  This can prove to be too time consuming and messy for owners.  If this is the case, it can be recommended that this treatment is for patients only where the buildup of excess keratin causes discomfort.  

Dogs with severe hyperkeratosis can actually be treated by removing the excess keratin with scissors or a razor blade.  If you wish, your veterinarian can show you how to do this so that you can do it at home.  You may not have to do it very often if you also use softening agents and hydrating agents on the affected areas.  An antiseborrheic agent will likely be suggested by your veterinarian as it can decrease the amount of build up in the area. 

If your dog has hyperkeratinization on his feet, it is recommended to soak them in water for 5 to 10 minutes periodically.  If his nose is affected, you should apply a wet compress for the same amount of time.  Once hydrated after soaking, you will need to cover the area with keratolytic agent.  These agents may include ichthammol ointment, petroleum jelly, tretinoin gel, 50% propylene glycol, and even some human dry skin lotions.

Treating nasodigital hyperkeratosis is all about management of the condition.  There is no cure and there is no stopping the development of keratin.  You can, however, try to slow the progression and remove built up parts that are making your dog uncomfortable.  This condition can make walking painful for the dog, especially if he is a heavier weight so keeping your dog happy and comfortable is ideal.