Alopecia areata in Eringer cows

Alopecia areata is a hair loss disorder in humans, dogs and horses with a suspected autoimmune aetiology targeting anagen hair follicles. Alopecia areata is only sporadically reported in cows. Recently, we observed several cases of suspected alopecia areata in Eringer cows. The aim of this study was to confirm the presumptive diagnosis of alopecia areata and to define the clinical phenotype and histopathological patterns, including characterization of the infiltrating inflammatory cells. Twenty Eringer cows with alopecia and 11 Eringer cows without skin problems were included in this study. Affected cows had either generalized or multifocal alopecia or hypotrichosis. The tail, forehead and distal extremities were usually spared. Punch biopsies were obtained from the centre and margin of alopecic lesions and normal haired skin. Histological examination revealed several alterations in anagen hair bulbs. These included peri‐ and intrabulbar lymphocytic infiltration, peribulbar fibrosis, degenerate matrix cells with clumped melanosomes and pigmentary incontinence. Mild lymphocytic infiltrative mural folliculitis was seen in the inferior segment and isthmus of the hair follicles. Hair shafts were often unpigmented and dysplastic. The large majority of infiltrating lymphocytes were CD3⁺ T cells, whereas only occasional CD20⁺ lymphocytes were present in the peribulbar infiltrate. Our findings confirm the diagnosis of T‐cell‐mediated alopecia areata in these cows. Alopecia areata appears to occur with increased frequency in the Eringer breed, but distinct predisposing factors could not be identified.     

Alopecia areata (pelade) in a cow

A case of alopecia areata (pelade) is described in a cow. Alopecia areata is a rare idiopathic dermatosis of cattle. It is characterized by asymptomatic, solitary or multiple, annular areas of noninflammatory alopecia. Scrapings and cultures are negative, and the diagnosis is confirmed by skin biopsies taken from early lesions, which reveal accumulations of lymphocytes around the bulbs of anagen hair follicles. There is no known effective and practical treatment for affected cattle. The dermatitis is a cosmetic problem, but does not seem to affect general health and production, and spontaneous remission may occur.     

Alopecia areata and humpy-back syndrome in suckling piglets

This report describes an uncommon variant of humpy-back syndrome associated with multiple rib fractures and multisystemic vasculitis in several nursing piglets and, for the first time, a skin disease in swine consistent with alopecia areata. Both conditions were observed concurrently on the farm and occasionally in the same piglets.     

Alopecia areata with lymphocytic mural folliculitis affecting the isthmus in a thoroughbred mare

A 13-year-old, thoroughbred mare was presented with an 8-year history of multifocal, generalized, noninflammatory alopecia and a 3-month history of alopecia, erythema and scaling of the white star on the forehead and muzzle. Histopathological examination of biopsy samples from multiple sites on the body (mane, neck, shoulder, flank and gluteal region) showed a subtle lymphocytic inflammatory infiltrate affecting and surrounding the anagen hair bulbs, consistent with a diagnosis of alopecia areata. The biopsy sample from the star on the forehead showed atrophic hair follicles with perifollicular and mural mononuclear folliculitis affecting the isthmus. Immunohistochemical staining with a CD3 marker confirmed the T-lymphocytic origin of the inflammatory infiltrate in all the samples. The concurrent presence of lymphocytic infiltration at the bulbar and isthmic level of the hair follicles in the same horse is unusual. This finding may represent a variation of the histological appearance of alopecia areata.     

犬脱毛症的病因与治疗

在犬的生理周期中，很多犬有季节性的脱毛与换毛现象，尤其以长毛犬最为明显。通常把病理性的局部或全身性脱毛称为脱毛症，在犬病临床中所占比例较大，约为20％左右。脱毛不仅影响美观，而且还可能会传播给犬主潜在的疾病。导致脱毛症状的病因较复杂，并且往往伴有其它的症状，治疗方法也各异。     

Alopecia Universalis in a Horse

Abstract— Alopecia universalis was diagnosed in a 3-year-old brown Percheron mare. Clinical and histo-pathologic findings in this previously unreported condition in the horse are described.     

Alopecia areata in C3H/HeJ mice involves leukocyte-mediated root sheath disruption in advance of overt hair loss

Alopecia areata (AA) can be induced in C3H/HeJ mice by grafting full-thickness AA-affected skin. An 8- to 12-week delay between surgery and overt hair loss onset provides an opportunity to examine disease pathogenesis. Normal haired C3H/HeJ mice were sham-grafted or grafted with AA-affected skin. Mice were euthanatized 2, 4, 6, 8, 10, and 12 weeks after surgery along with chronic AA-affected mice as a positive control. Until 6 weeks after grafting, inflammation was only evident around anagen-stage hair follicles in host skin adjacent to but not distant from the AA-affected graft. From 8 weeks on, AA-grafted but not sham-grafted mice exhibited a diffuse dermal inflammation at distant sites that progressively focused on anagen-stage hair follicles at 10 and 12 weeks. Perifollicular inflammation was primarily composed of CD4+ and CD8+ cells associated with follicular epithelium intercellular adhesion molecule -1 expression. Only CD8+ cells penetrated intrafollicularly by 12 weeks after surgery, although both CD4+ and CD8+ intrafollicular cells were observed in chronic AA-affected mice. Under electron microscopy, intrafollicular lymphocyte and macrophage infiltration associated with hair follicle dystrophy was prominent 10 weeks after surgery, primarily within the differentiating outer and inner root sheaths. This study shows that focal follicular inflammation develops some time in advance of overt hair loss and focuses on the differentiating root sheaths in C3H/HeJ mice. The severity of inflammation and the degree of hair follicle dystrophy induced by the infiltrate appear to reach a threshold level before overt hair loss occurs.     

Alopecia Mucinosa (Follicular Mucinosis) in a Dog

Abstract— A 10-year-old male Labrador Retriever dog presented with alopecia and scaling that was extensive in the head and limb regions and patchy over the trunk. The major histopathological feature was degeneration of the outer root sheath with disruption of keratinocytes and formation of cystic spaces filled with mucin. A diagnosis of follicular mucinosis was made. This case report represents the first case of this syndrome in the canine species.
Résumé— Un Labrador, mâle de 10 ans est présenté pour une alopécie squameuse, extensive, de la tête, des membres, et en "taches" sur le tronc. La lésion histopathologique principale est une dégénérescence de la gaine externe du poil avec dislocation des kératinocytes et la formation d'espaces kystiques remplis de mucine. Un diagnostic de mucinose folliculaire a été fait. Ce caqs est le premier décrit chez le chien. [Bell, A., Oliver, F. Alopecia mucinosa (follicular mucinosis) in a dog (Alopecia Mucinosa (mucinose folliculaire) chez un chien).     

Trachyonychia associated with alopecia areata in a Rhodesian Ridgeback

Trachyonychia associated with alopecia areata was diagnosed in an 8-year-old Rhodesian Ridgeback. Clinical and histological findings are described in this respectively unreported and rare condition in the dog.     

Phycomycosis in a dog

SUMMARY A case of phycomycosis, with skin lesions, in a dog is reported. Hyphomyces destruens (Pythium gracile) was identified from aspirate collected from a regional lymph node, and characteristic hyphae were seen in stained sections of a biopsy specimen of affected skin. Incidence, pathogenesis and therapy are discussed.     

Protothecosis in a dog

A case of a disseminated algal infection is reported in a young rough-coated collie dog with progressive neurologic deficits, blindness, and hemorrhagic diarrhea. Prototheca zopfii organisms were cultured from feces, urine, and blood. At necropsy, granulomas containing typical organisms were identified within the proximal colon, heart, kidneys, and eyes.