Abstract
Purpose: :
To describe common ophthalmic lesions observed on clinical and histopathological examination in Doberman Pinscher dogs exhibiting the recessively inherited albino "white" phenotype.
Methods: :
Standard ophthalmologic exams consisting of applanation tonometry, slit-lamp biomicroscopy, and indirect ophthalmoscopy were performed by a single investigator (JB) on 20 white Doberman Pinschers (WDP) and 20 standard coat-color Doberman Pinschers (SDP). Dogs were also evaluated grossly for cutaneous masses which were biopsied and submitted for histopathology. Numeric data were compared between sample populations using T-test or Chi-square analysis with statistical significance set at P≤ 0.05.
Results: :
11 male and 9 female WDP with an age range of 1 to11 (X: 4.7± 2.7) years and 13 male and 7 female SDP with an age range of 1 to 13 (X: 5.5± 4.2) years were examined. Intraocular pressure ranged from 8 to 21 (X: 14.00± 3.41) mmHg in WDP and 8 to 24 (X: 13.45± 3.49) mmHg in SDP. WDP ocular lesions invariably included: photophobia in sunlight, iridal transillumination defects, vertically-oriented ovoid dyscoria, and hypopigmentation of eyelid/nictitans margins, cilia, iridal stroma, and nontapetal fundus; none of these lesions were observed in SDP. Variable ocular lesions included iridociliary cysts (4/20 WDP, 0/20 SDP, P=0.146) and cataracts (4/20 WDP, 1/20 SDP, P=0.151). Cutaneous tumors were noted in 12/20 WDP (<5 years of age: 4/12; >5 years of age: 8/8) and 1/20 SDP (P<0.00001). Histopathology revealed all tumors evaluated in WDP were of melanocytic origin with cellular diagnosis ranging from benign melanocytoma to malignant melanoma.
Conclusions: :
WDP have multiple ocular abnormalities not observed in SDP including: photophobia, iridal stromal defects, and hypopigmentation of adnexal and intraocular structures. WDP show significantly higher incidence of cutaneous melanocytic neoplasia compared to SDP. These findings are similar to humans with oculocutaneous albinism and suggest the white Doberman Pinscher dog is an ideal animal model to further investigate the pathogenesis of this group of human conditions.
Keywords: melanoma • tumors • eyelid