Also Known As: Canine pinnal alopecia, acquired pattern alopecia.
Transmission or Cause: A breed-associated genetic disorder of hair follicle miniaturization.
Affected Animals: Often seen in small, thinly-haired dog breeds such as Daschunds, Italian Greyhounds, Whippets, Chihuahuas, Miniature pinschers and Boston terriers.
Clinical Signs: Symptoms usually begin in late puberty or young adulthood. Symmetrical thinning of hair or hair loss commonly occurs on the outer ear flaps, under the neck, on the chest, backs of the thighs, and behind the ears. There is no associated skin inflammation, itch, redness, or rash. In Dachshunds with hairloss on the outer ear flaps, complete hairloss usually occurs by 8-9 years of age and the exposed skin becomes dark/hyperpigmented.
Diagnosis: Diagnosis is made by consideration of breed and location of hairloss, as well as ruling out other causes of hairloss such as skin infections or hormonal disease. Skin biopsy shows tiny hair follicles with fine hair shafts, but no follicular distortion, inflammation or other abnormalities.
Treatment: In some cases, partial hairgrowth may occur with oral melatonin supplementation.
Prognosis: Although the prognosis for normal hairgrowth is poor, this is only a cosmetic disorder, which does not interfere with the pet’s quality of life.