November 2016



Slide A
Signalment (JPC 1368758):  3-year-old German shepherd dog

HISTORY:  Euthanized because of generalized chronic dermatitis

HISTOPATHOLOGIC DESCRIPTION:  Haired skin:  Multifocally within the dermis there is perifolliculitis composed of moderate numbers of lymphocytes, plasma cells, macrophages, and fewer neutrophils.  Inflammatory cells occasionally infiltrate and partially disrupt follicular epithelium (interface mural folliculitis), and there is hydropic degeneration and single-cell necrosis of follicular epithelial cells.  Filling and expanding follicles are segments of arthropods, up to 40 um in diameter and 200 um in length, with a thin, eosinophilic, chitinous exoskeleton, short jointed appendages, a hemocoel, striated muscle, and digestive and reproductive tracts.  There are few pigment-laden melanomacrophages surrounding follicles (pigmentary incontinence).  Diffusely, there is moderate follicular and epidermal hyperplasia with orthokeratotic hyperkeratosis.  Apocrine glands are mildly ectatic, occasionally hyperplastic and filled with varying amounts necrotic debris.

Tongue:  No significant lesions.

MORPHOLOGIC DIAGNOSIS:  Haired skin:  Dermatitis, perifolliculitis, and interface mural folliculitis, lymphoplasmacytic and histiocytic, chronic, multifocal, moderate, with epidermal and follicular hyperplasia, hyperkeratosis, and intrafollicular mites, etiology consistent with Demodex canis, German shepherd dog, canine.

ETIOLOGIC DIAGNOSIS:  Follicular demodicosis

CAUSE:  Demodex canis

CONDITION:  Demodectic mange

CONDITION SYNONYMS:  Red mange; follicular mange

Slide B
Signalment (JPC 1051577):  A pig


HISTOPATHOLOGIC DESCRIPTION:  Haired skin and subcutis:  Diffusely, hair follicles are markedly ectatic, up to 2‑3 mm in diameter, and lined by degenerate epithelial cells.  These follicles are expanded and filled with numerous elongate mites that are 40 um wide and 150-200 um long, with a thin, eosinophilic, chitinous exoskeleton, short jointed appendages, a hemocoel, striated muscle, and digestive and reproductive tracts.  Multifocally surrounding hair follicles, sebaceous glands, and blood vessels are few lymphocytes, plasma cells, macrophages, and eosinophils.  Multifocally, apocrine glands are mildly ectatic and filled with numerous neutrophils.  Diffusely, the epidermis and hair shafts are absent (due to slaughter scalding and processing).

MORPHOLOGIC DIAGNOSIS:  Haired skin and subcutis:  Follicular ectasia, multifocal, marked, with periadnexal and perifollicular lymphoplasmacytic and eosinophilic dermatitis, moderate neutrophilic apocrine adenitis, and numerous intrafollicular mites, etiology consistent with Demodex phylloides, breed not specified, porcine.

ETIOLOGIC DIAGNOSIS:  Follicular demodicosis

CAUSE:  Demodex phylloides

CONDITION:  Demodectic mange

CONDITION SYNONYMS:  Red mange; follicular mange






Localized form:

Generalized form:



For gross lesions:

For histologic lesions:



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