奥拉替尼有效治疗犬寻常型天疱疮1例报告 - 宠医帮

Pemphigus vulgaris is a rare immune-mediated skin disorder of the dog, usually treated with immunosuppressive medications such as oral glucocorticoids, azathioprine or ciclosporin. Herein we report the successful treatment of pemphigus vulgaris in a dog, using oclacitinib and a topical product containing fucidic acid (0.5 % w/w) and betamethasone valerate.

In dogs, pemphigus vulgaris (PV) is a rare immunemediated skin disease which presents with vesicles and erosions on the mucosal surfaces, mucocutaneous junctions and/or nonmucosal skin. Studies have demonstrated that desmoglein 3 (DSG3) is the main target of autoantibodies in cases of canine PV. Treatments that often are used to treat PV in the dog include glucocorticoids, azathioprine, ciclosporin, chlorambucil, aurothioglucose, heparin and doxycycline. A recent review of deep pemphigus, found that of the reported cases of PV in the veterinary literature, clinical remission (CR) was achieved in only 65% (26 of 40) of treated dogs. Spontaneous remission without treatment was reported in only one of 40 dogs (3%). In addition, some of the traditional therapies may produce adverse effects, especially when used at immunosuppressive doses.

在犬上，寻常型天疱疮(PV)是一种罕见的免疫介导性皮肤病，表现为粘膜表面、粘膜皮肤交界处和/或非粘膜皮肤上出现水疱和糜烂。研究表明，在犬PV病例中，桥粒芯蛋白3 (DSG3)是自身抗体的主要靶点。治疗犬PV的方法通常包括糖皮质激素、硫唑嘌呤、环孢素、苯丁酸氮芥、金硫葡糖、肝素和多西环素。最近一篇关于深层天疱疮的综述发现，在兽医文献中报道的PV病例中，接受治疗的犬只有65%(26 / 40)获得临床缓解(CR)。40只犬中只有1只(3%)无治疗而自行缓解。此外，一些传统疗法可能产生副作用，特别是在使用免疫抑制剂量时。

A 5-year-old female, entire ex-racing greyhound was presented for evaluation of bilateral otitis externa (OE) and ulceration of the concave pinnae. The OE had been present for approximately six months and initial treatment had included a topical ear compound containing gentamicin sulfate, nystatin and fluocinolone acetonide (Topigen, Ilium, Troy Laboratories Australia Pty; Glendenning, NSW, Australia) for two weeks, and oral amoxycillin-clavulanic acid at 12.5 mg/kg twice daily (Amoxyclav, Apex, Dechra Veterinary Products Pty; Somersby, NSW, Australia). The amoxycillin-clavulanic acid was discontinued after five days as the dog became inappetent and lethargic, and had lost weight. The medical record indicated that the pinnal ulceration was apparent at five days post commencement of these treatments. Cephalexin (Apex, Dechra Veterinary Products Pty) was prescribed at a dose of 20 mg/kg twice daily, and was stopped by the owner after five days as a consequence of inappetence. All medications, including topical aural preparations, were discontinued until the dog was presented to another first opinion practice two months later. Clinical notes indicated that bilateral pinnal ulcerations were present, and cytological evaluation of the otic canal revealed cocci and inflammatory cells. A swab was taken from the ear canal for culture and sensitivity which showed a heavy growth of multidrug-resistant Staphylococcus pseudintermedius. The dog subsequently was referred to the authors’ clinic for further investigation.

一只5岁雌性未绝育前赛级灵缇犬因双侧外耳炎(OE)和耳廓凹面溃疡就诊。OE已存在约6个月，最初的治疗包括外用耳药，其中含有硫酸庆大霉素、制霉菌素和氟轻松(Topigen），连续使用2周，以及口服阿莫西林-克拉维酸12.5 mg/kg，每日两次。阿莫西林-克拉维酸在5天后停止使用，因为犬变得食欲下降和嗜睡，体重下降。医疗记录表明，在治疗五天后，耳廓溃疡是明显可见。使用头孢氨苄每日两次，剂量为20 mg/kg, 5天后因食欲下降被主人停用。所有药物，包括外用耳药，都被停止，直到两个月后犬被送到另一个全科诊所。临床表现存在双侧耳廓溃疡，耳道细胞学检查显示有球菌和炎性细胞。从耳道拭子采样进行细菌培养和药敏试验，显示多重耐药假中间型葡萄球菌大量生长。这只犬随后被转诊到作者所在诊所作进一步检查。

Clinical evaluation revealed numerous ulcers on the concave surfaces of the pinnae (Figure 1a), small ulcers on the labial surface of the upper gums, punctate ulcers on the soft palate and a bilateral ceruminous otic discharge. A conscious otoscopic examination was not possible as the dog registered extreme pain on palpation of the pinnae. The dog underwent general anaesthesia for contrast-enhanced computed tomography of the head and neck, which showed evidence of bilateral otitis externa with thickening of the external ear canal walls, yet no abnormalities of the bullae or inner ears. Cytological evaluation of the ear canals revealed abundant coccoid bacteria both intracellularly in neutrophils and macrophages, as well as free in the background. Cytological evaluation from the surface of the ulcers on the medial pinnae revealed similar findings of coccoid bacteria, neutrophils and macrophages. There was only one intact vesicle visualised, so no attempts were made to collect a Tzanck prep or to produce a Nikolsky sign, in order to preserve the vesicle for biopsy and histological examination. One 6 mm punch biopsy was taken from each concave pinna and the oral mucosa. The ear canals were flushed with sterile saline (0.9% sodium chloride, Baxter Professional; Old Toongabbie, NSW, Australia) and both tympanic membranes were visualised and appeared intact. The dog was discharged with oral gabapentin (Neurontin 300 mg, Pfizer; Sydney, NSW, Australia) at 10 mg/kg three times a day, and compounded ear medication [2% fucidic acid, 2% rifampicin, 2% ketoconazole, 0.1% dexamethasone in squalene (NOVA; Melbourne, Australia)] at 1 mL bilaterally twice daily.

临床评估发现耳廓凹面有大量溃疡(图1a)，上牙龈唇面有小溃疡，软腭有点状溃疡，双侧耳道耵聍性分泌物。因为患犬耳廓触诊非常疼痛，无法在清醒情况下进行耳镜检查。患犬全身麻醉，进行了头部和颈部CT扫描，显示双侧外耳炎，外耳道壁增厚，但鼓泡或内耳没有异常。耳道细胞学检查显示，在中性粒细胞和巨噬细胞的细胞内以及背景中都有大量的球菌。从耳廓凹面溃疡表面的细胞学评估显示了类似的发现，球菌、中性粒细胞和巨噬细胞。观察到只有一个完整的水疱，因此没有进行细胞学检查采样或Nikolsky征检查，目的是采集完整水疱进行活检和组织学检查。从每个耳廓凹面和口腔粘膜都进行一个6mm打孔活检采样。无菌生理盐水冲洗耳道后，两个鼓膜都可观察到，看起来完整。犬出院后口服加巴喷丁10 mg/kg，每日3次，联用复方耳药[2%夫西地酸、2%利福平、2%酮康唑、0.1%地塞米松加入角鲨烯]，每耳1毫升，每日两次。

Histological examination of skin biopsy samples from the pinnae revealed clear suprabasilar clefting, with the base of the cleft being lined by plump basal epithelial cells with a tombstone appearance (Figure 2). There was mild basilar spongiosis and mild perivascular and interstitial infiltrates of mast cells, neutrophils, eosinophils and macrophages in the adjacent dermis.

A presumptive diagnosis of pemphigus vulgaris was made based on the characteristic features that were seen in histopathological findings, along with the clinical signs. Immunohistochemical analysis to identify autoantibodies is not readily available in the authors’ resident country, Australia. The owner was reluctant to administer oral glucocorticoids to the dog, so treatment was initiated with oclacitinib at a dose of 0.5 mg/kg twice daily, and topical fucidic acid (0.5 % w/w) and betamethasone valerate (0.1 % w/w) (Isaderm, Dechra; Somersby, Australia) was applied to the pinnal ulcers twice daily. When the dog was evaluated 10 days later, the pinnal lesions had improved (Figure 2b) and the oral lesions had resolved completely. The compounded aural medication, gabapentin and topical fucidic acid and betamethasone were continued for another 10 days and then discontinued, while the oclacitinib was continued at the same dose for a total of six weeks. The lesions had all resolved by six weeks, and the last communication from the owner, two months after discontinuation of the oclacitinib, indicated that there had been no relapse of disease.

根据组织病理学所见的特征以及临床症状，推测诊断为寻常型天疱疮。在作者的居住国澳大利亚，免疫组化分析识别自身抗体并不容易。主人不愿意给犬口服糖皮质激素，因此初期治疗使用奥拉替尼剂量为0.5 mg/kg, 每天2次，耳廓溃疡外用夫西地酸(0.5% w/w)和戊酸倍他米松(0.1% w/w)，每日两次。10天后对犬进行评估时，耳廓病变已改善(图2b)，口腔病变已完全恢复。复方耳药、加巴喷丁和外用夫西地酸和倍他米松，再连续使用10天，随后停药，而奥拉替尼以相同剂量持续6周。病变在六周后全部消失，在停用奥拉替尼两个月后，主人的最后一次通讯表明，疾病没有复发。

Clinical signs related to PV were controlled with oclacitinib and topical fucidic acid and betamethasone in the dog in this case report. PV is an autoimmune dermatological disease, and possible triggers can include drug reactions or paraneoplastic syndromes, although most cases are idiopathic. A case of suspected polymyxin Binduced PV has been reported, and White et al. described a series of four dogs with putative druginduced pemphigus foliaceous following administration of oral antimicrobials, some of which included beta lactam drugs. The pinnal lesions in the dog in our case report were reported to have occurred five days after commencement with amoxicillin-clavulanic acid and Topigen ear drops, with the dog also becoming inappetent and lethargic, and losing weight. The timing of observed clinical signs five days after the use of amoxicillin-clavulanic acid does fit with a previous report of suspected druginduced PV. Although the putative causative drug in this case was stopped three months before presentation to the authors’ clinic, it did not result in resolution of the dermatological signs. Previous prednisolone use in the dog had resulted in undesirable adverse effects including lethargy, excessive panting, polydipsia and polyuria, so the owner was very reluctant to administer systemic glucocorticoids again. The authors felt that the published literature supporting the use of oclacitinib for immune-mediated skin diseases, and the typically reduced systemic adverse effects compared to other immunosuppressive medications, justified its off-label use in this case.

在这一病例报告中，患犬与PV相关的临床症状，在使用奥拉替尼和外用夫西地酸和倍他米松后得以控制。PV是一种自体免疫性皮肤病，可能的诱因包括药物反应或副肿瘤综合征，但大多数病例是特发性的。已经报道了一例疑似多粘菌素诱导的PV病例，White等人描述了一系列的四只犬在口服抗菌药(其中一些包括β-内酰胺类药物)后被认为是药物诱导的落叶型天疱疮。在我们的病例报告中，在使用阿莫西林-克拉维酸和Topigen耳药5天后，犬的耳廓病变发生，犬也变得食欲下降、嗜睡和体重减轻。在使用阿莫西林-克拉维酸5天后观察到的临床症状的时间与先前的疑似药物诱导PV的报告相符。虽然在这个病例中假定的致病药物在转诊到作者诊所前三个月就停止了，但它并没有导致皮肤症状的缓解。患犬曾经使用泼尼松龙会导致不接受的副作用，包括嗜睡、呼吸加快、多饮和多尿，所以主人非常不愿意再次给它全身使用糖皮质激素。作者认为，已发表的文献支持使用奥拉替尼治疗免疫介导性皮肤病，与其他免疫抑制药物相比，其典型的全身性副作用更少，因此在该病例中证明了标签外用药的合理性。

The exact role of oclacitinib in the treatment of autoimmune diseases is unknown. This has been proposed to be due to its ability to modify lymphocyte proliferation and function, as well to modify cytokine production. By modifying cytokine production and downstream gene transcription, production of immunoglobulins important in the pathogenesis of PV, such as immunoglobulin (Ig)G, may be reduced.Although IgG antibodies against DSG3 have been identified in cases of canine PV, it also has been proposed that IgG-independent factors such as helper T-cell (Th)2 cytokines, tumour necrosis factor a and Fas ligand also may play a role in the pathogenesis of acantholysis in PV. An in vitro study on the effects of oclacitinib on T-cell proliferation and cytokine production, found that oclacitinib significantly reduced the secretion of clonal activator cytokines [interleukin (IL)-2, IL-15], proinflammatory cytokines (interferon-gamma, IL-18) and the regulatory cytokine IL-10; tumour necrosis factor a and IL-6 production was inhibited mildly. This effect was seen only when oclacitinib was used at much higher concentrations (3–4 mg/kg) than the labelled 0.4–0.6 mg/kg once daily dose. However, in our case we used a dose of 0.5 mg/kg twice daily and clinical improvement was noted within 10 days, with complete resolution by six weeks.

奥拉替尼在自体免疫性疾病治疗中的确切作用尚不清楚。认为由于其能够改变淋巴细胞的增殖和功能，也改变细胞因子的产生。通过改变细胞因子的产生和下游基因的转录，PV发病机制中重要的免疫球蛋白的产生，如免疫球蛋白(Ig)G的产生可能会减少。虽然在犬PV病例中发现了抗DSG3的IgG抗体，但也有人提出，IgG无关因子如辅助T细胞(Th)2细胞因子、肿瘤坏死因子a和Fas配体也可能在PV的棘层松懈发病机制中发挥作用。体外研究奥拉替尼对T细胞增殖和细胞因子产生的影响发现，奥拉替尼显著降低了克隆激活因子[白介素(IL)-2、IL-15]、促炎因子(干扰素-γ、IL-18)和调节性细胞因子IL-10的分泌，肿瘤坏死因子a和IL-6的产生被轻度抑制。这种效果仅在使用更高浓度的奥拉替尼(3-4 mg/kg)时才出现，而不是标签剂量，0.4-0.6 mg/kg，每日一次。但是，在我们的病例中，我们每天两次使用0.5 mg/kg的剂量，10天内就出现了临床改善，6周后完全缓解。

There have been reports of oclacitinib’s successful use in other immune-mediated dermatoses of dogs and cats including pemphigus foliaceous, ischaemic dermatopathy and ear tip ulcerative dermatitis, as well as in a case of autoimmune subepidermal blistering dermatosis. The clinical resolution of the dog in this case report also may have been in part a result of the application of topical glucocorticoid and antibiotic, yet this would not explain the complete resolution of the oral lesions where topical therapy was not applied.

已有报道称，奥拉替尼成功用于犬和猫的其他免疫介导性皮肤病，包括落叶型天疱疮、缺血性皮肤病和耳尖溃疡性皮肤病，以及一例自体免疫性表皮下水疱性皮肤病。在本病例报告中，犬的临床缓解也可能是外用糖皮质激素和抗生素的结果，但这不能解释没使用外部治疗的口腔病变的完全缓解。

In conclusion, this case report demonstrates the resolution of clinical signs of PV in a dog with the use of oclacitinib, along with a topical glucocorticoid and antimicrobial ointment, and discontinuation of other medications that may have been triggers for the disease. It may be worthwhile to consider the use of oclacitinib in other cases of canine PV where the use of traditional immunosuppressive medications may be contraindicated.