Department of Small Animal Clinical Sciences, Michigan State University, Veterinary Medical Center, 736 Wilson Road, East Lansing, MI, 48824, USA.
Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA.
BMC Vet Res. 2021 Dec 1;17(1):366. doi: 10.1186/s12917-021-03072-9.
Despite the common use of topical ophthalmic corticosteroids in dogs, detailed reports on systemic and dermatologic adverse effects are limited.
Nine purpose-bred research Beagles were treated with difluprednate 0.05% ophthalmic emulsion in one or both eyes 2-3 times daily. Some difluprednate treated dogs developed mild to severe alopecia of the periocular region, face, and distal pinna (5/9). The median duration of treatment prior to onset of dermatologic signs for difluprednate treated dogs was 550 days (453-1160 days). Diagnostic testing included complete blood count (CBC) and serum biochemistry, adrenocorticotropic hormone (ACTH) stimulation testing combined with endogenous ACTH measurement, and skin biopsy. The CBC and chemistry were within normal limits for all dogs. There were varying degrees of suppression of the hypothalamic-pituitary-adrenocortical (HPA) axis with difluprednate treatment. Dogs with the most profound alopecic changes had less pronounced HPA axis suppression compared to dogs with no integumentary changes. Skin biopsies demonstrated follicular atrophy and follicular keratosis. When topical difluprednate was reduced to unilateral therapy, the hair regrew on the untreated side of the face. In addition to the affected research dogs, a 7-year old female spayed Chihuahua that was being treated as a clinical patient with long-term difluprednate 0.05% ophthalmic emulsion developed generalized hypotrichosis on the head and body and a potbellied appearance. ACTH stimulation testing revealed suppression of the HPA axis with a mild increase in serum alkaline phosphatase (ALP) activity and a urine specific gravity of 1.016. The combination of clinical signs and laboratory abnormalities was supportive of iatrogenic hyperadrenocorticism.
In dogs long-term use of difluprednate ophthalmic emulsion results in HPA axis suppression and in some cases iatrogenic hyperadrenocorticism. A novel pattern of localized alopecia is suspected to be related to dermal absorption and local action due to superior potency and penetration compared to other commonly utilized ophthalmic corticosteroids.
尽管犬科动物经常使用局部眼部皮质类固醇，但有关全身性和皮肤不良反应的详细报告却很有限。
9 只特定品种的研究比格犬每天用 0.05%二氟泼尼龙眼部乳剂治疗一只或两只眼睛 2-3 次。一些用二氟泼尼龙治疗的狗出现了眼周、面部和远端耳郭的轻度至重度脱毛（5/9）。开始出现皮质类固醇治疗犬的皮肤症状之前，接受二氟泼尼龙治疗的狗的中位治疗时间为 550 天（453-1160 天）。诊断测试包括全血细胞计数（CBC）和血清生化检查、促肾上腺皮质激素（ACTH）刺激试验结合内源性 ACTH 测量以及皮肤活检。所有狗的 CBC 和化学值均在正常范围内。二氟泼尼龙治疗后，下丘脑-垂体-肾上腺皮质（HPA）轴的抑制程度不同。脱发变化最严重的狗与皮肤无变化的狗相比，HPA 轴抑制程度较轻。皮肤活检显示毛囊萎缩和毛囊角化过度。当局部二氟泼尼龙减少为单侧治疗时，脸部未治疗侧的毛发重新生长。除了受影响的研究犬外，一只 7 岁的雌性去势吉娃娃犬因长期使用 0.05%二氟泼尼龙眼部乳剂作为临床患者而患有头部和身体的广泛性脱发和腹部突出。ACTH 刺激试验显示 HPA 轴受到抑制，血清碱性磷酸酶（ALP）活性轻度增加，尿比重为 1.016。临床症状和实验室异常的组合支持医源性库欣氏综合征。
在犬科动物中，长期使用二氟泼尼龙眼部乳剂会导致 HPA 轴抑制，在某些情况下还会导致医源性库欣氏综合征。局部脱发的新发病模式可能与真皮吸收和局部作用有关，因为与其他常用眼部皮质类固醇相比，它具有更强的效力和穿透力。
