CUTANEOUS MANIFESTATIONS OF ENDOCRINE DISEASE IN DOGS

Endocrinopathies are commonly associated with cutaneous changes. The m ost common gross morphologic changes are relatively nonspecific and in clude varying degrees of seborrhea (sicca or oleosa); abnormal sheddin g patterns; and a bilaterally symmetric, nonpruritic alopecia that ten ds to spare the head and distal extremities. Lightening of coat color and cutaneous hyperpigmentation are also common. Changes that are more consistent with specific endocrinopathies include cutaneous atrophy a ssociated with hyperadrenocorticism, hyposomatotropism, testosterone-r esponsive dermatosis; phlebectasias associated with spontaneous or iat rogenic hyperadrenocorticism; atypically large bacterial pustules asso ciated with hyperadrenocorticism or hypothyroidism; perianal adenomas and adenocarcinomas associated with spontaneous hyperadrenocorticism; calcinosis cutis associated with hyperadrenocorticism; the patterns of alopecia associated with sex-hormone imbalances; hair regrowth at sit es of trauma associates with castration-responsive dermatosis, hyposom atotropism, and the congenital adrenal hyperplasia-like syndrome; line ar preputial erythema associated with Sertoli's cell tumor; perianal h yperplasia, supracaudal tail gland hyperplasia, and prostatomegaly ass ociated with hyperandrogenism due to interstitial cell tumors; and the well-demarcated flank and lateral thoracoabdominal alopecia associate d with melatonin-responsive flank alopecia. Histologic examination of the skin often suggests the presence of an endocrinopathy. Although mo st changes are nonspecific, some histologic tip-offs help to narrow th e list of differential diagnoses.