Image Quiz: Dermatology-A pit bull with bullous lesions

Solar dermatitis is correct!

Note the restriction of the lesions to the nonpigmented areas on the trunk and the severe involvement of the unhaired ventrum. To achieve the correct diagnosis, be sure to note the appearance and distribution of the lesions, perform skin scrapings and skin cytology to rule out infectious causes of furunculosis, and obtain a skin biopsy sample for histopathologic and dermatopathologic examination. Treatment is strict sun avoidance; concurrent secondary pyoderma must also be treated with appropriate antibiotics based on culture results for a minimum of four weeks.