Dilated pore of Winer in a dog.

A 9-year-old male neutered Goldendoodle was presented to the Animal Medical Center of Seattle with a history of a firm, hairless, cystic mass on the dorsal aspect of the neck. The mass had been present for 2 years and would periodically rupture and discharge moderate quantities of yellow-green, soft, semi-solid, keratinaceous material. As rupture of the mass was reported to cause the patient significant pain and discomfort, it was surgically excised. Histopathology of the mass revealed a bulbous keratin-filled cyst that communicated with the external environment via a small ostium. At the base of the cyst, the cyst lining was characterized by a markedly irregular and hyperplastic stratified squamous epithelium with an overt stratum granulosum and prominent, irregularly sized, shaped and spaced rete ridges. At the superficial aspect of the cyst near the ostium, the cystic lining was characterized by a relatively thinner stratified squamous epithelium with an overt stratum granulosum and regular basal contour. Based on the histomorphological appearance of the mass, a diagnosis of a dilated pore of Winer was made. Dilated pores of Winer are follicular cysts arising from the infundibulum of the hair follicle. They are relatively common in humans and uncommon in cats, and single case reports have been described in a horse and a woodchuck (Marmota monax). To the best of the authors' knowledge, this is the first description of a dilated pore of Winer in a dog.

Age- and breed-matched retrospective cohort study of malignancies and benign skin masses in 660 dogs with allergic dermatitis treated long-term with versus without oclacitinib.

OBJECTIVE: To compare the cumulative incidences of malignancies and benign skin masses and the mean age at death or euthanasia in dogs with allergic dermatitis treated long-term with versus without oclacitinib. ANIMALS: 660 client-owned dogs. PROCEDURES: Medical records were searched to identify dogs with allergic dermatitis treated for ≥ 6 months with oclacitinib (exposed dogs; n = 339) versus other available treatments before the introduction of oclacitinib (nonexposed dogs; 321) and with ≥ 24 months of follow-up information available. Nonexposed dogs were age and breed matched with 321 of the exposed dogs; data for the remained 18 exposed dogs were included in statistical analyses. Results for cumulative incidences of malignancies and other variables were compared between groups, and the effect of daily maintenance dosage of oclacitinib on cumulative incidences of malignancies and other skin masses was evaluated within the exposed group. RESULTS: No meaningful differences were detected in the cumulative incidences of malignancies and overall skin masses or the mean age at death or euthanasia for dogs in the exposed group (16.5% [56/339], 56.6% [192/339], and 11.2 years [n = 80], respectively) versus the nonexposed group (12.8% [41/321], 58.3% [187/321], and 11.8 years [71], respectively). There was no association identified between daily maintenance dosage of oclacitinib and odds of malignancy or benign skin masses for dogs in the exposed group. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that long-term treatment with oclacitinib did not pose additional risk for malignancy in dogs; however, veterinarians should continue to observe FDA-approved label warning and precaution statements for oclacitinib and regularly screen for neoplasia in dogs with allergic skin disease treated with or without oclacitinib.

Comparison of two ear cytological collection techniques in dogs with otitis externa.

BACKGROUND: Canine otitis externa is a common disease. Cytological evaluation of otic exudate is a useful diagnostic test to direct and monitor treatment for otitis externa. One method of collecting ear cytological specimens utilizes a cotton-tipped swab inserted into the vertical ear canal. A proposed alternative method is to aspirate exudate from the deep horizontal canal using a rubber tube. HYPOTHESIS/OBJECTIVES: To compare cytological findings between two different collection techniques by evaluating the numbers of bacteria, Malassezia yeast and inflammatory cells. ANIMALS: Thirty client-owned dogs with otitis externa. METHODS AND MATERIALS: A prospective, randomized, blinded comparison study. Ear canals from each dog were sampled using cotton swab and rubber tube. Ear cytological preparations were evaluated independently by two investigators for polymorphonuclear leucocytes (PMN), monocytes/lymphocytes, macrophages, yeast, intracellular (IC) cocci, extracellular (EC) cocci, IC bacilli and EC bacilli. RESULTS: A paired Student's t-test was used to compare the two techniques. The inter-investigator reliability for PMN, EC bacilli and yeast was good, and for EC cocci was moderate. There were significantly higher numbers of PMNs obtained by the tube method (P = 0.0024) than by the cotton swab method. There were no statistically significant differences between cotton swab and rubber tube methods for monocytes/lymphocytes (P = 0.7780), macrophages (P = 0.1751), EC cocci (P = 0.1262), EC bacilli (P = 0.1162), yeast (P = 0.5371), IC cocci (P = 0.6606) or IC bacilli (P = 0.6761). The technique was well tolerated. CONCLUSION: An alternative ear cytological collection technique was identified which enables sampling of the deep horizontal canal.

Resident lymphocytes in the dermis of the normal dorsolateral thoracic skin of alpacas.

BACKGROUND: Small numbers of resident T lymphocytes are present in the dermis of normal skin of humans, cattle and sheep. HYPOTHESIS/OBJECTIVES: We wanted to determine the prevalence, numbers and immunophenotype of lymphocytes in the dermis of healthy skin from alpacas. ANIMALS: Skin biopsy specimens were collected from the dorsolateral thorax of 31 alpacas with normal skin. METHODS: Skin biopsy specimens were evaluated for the prevalence and numbers of CD3+ and CD79a+ lymphocytes. RESULTS: Resident CD3+ and CD79a+ lymphocytes were found around the superficial and deep dermal blood vessels. The CD3+ lymphocytes were more numerous than CD79a+ lymphocytes. Both CD3+ and CD79a+ lymphocytes were more numerous around superficial dermal blood vessels. CONCLUSIONS AND CLINICAL IMPORTANCE: Resident CD3+ and CD79a+ lymphocytes are present around superficial and deep dermal blood vessels in normal skin from alpacas; hence, the presence of lymphocytes in these locations without obvious features of inflammation must be interpreted cautiously when evaluating skin biopsy specimens from alpacas with skin disease.