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523.e2 Hypospadias

Hypospadias
VetBooks.ir Acute and Chronic Treatment

at the scrotum or perineum may have urinary
BASIC INFORMATION
incontinence and inguinal dermatitis due to Depends on the location of the urethral termi-
Definition urine dribbling and scalding. nation. Surgical apposition of the ventral penile
A rare condition in which the penile urethra urethral mucosa and tunica around a urethral
terminates proximal to the tip of the penis PHYSICAL EXAM FINDINGS catheter may be sufficient in some cases. There
The severity of the lesion varies from a slight have been individual reports of repairing a distal
Synonym deviation of the urethral orifice in the distal urethral defect using a preputial mucosal flap
Pseudohermaphrodite glans penis to a ventral cleft along the entire or reconstruction of a perineal defect using
length of the penis, prepuce, and scrotum, with bilateral perineal skin flaps. For those cases in
Epidemiology the urethral orifice located in the perineum. which the urethra terminates at the scrotum or
SPECIES, AGE, SEX the perineum, a scrotal or perineal urethrostomy
Hypospadias has been reported in dogs and Etiology and Pathophysiology may be possible, with amputation of the distal
cats. Affected animals can be genetically male • Most likely due to a defect in masculinization penis.
(XY), female (XX), or some form of intersex and incomplete fusion of the ventral raphe
(e.g., XX/XY, XX SRY positive). of the penis PROGNOSIS & OUTCOME
• May be due to a defect in androgen receptors
GENETICS, BREED PREDISPOSITION with the urogenital tubercle Good if a mild abnormality, fair for surgical
Most commonly reported in Boston ter- repair
riers; the genetic basis of the condition is DIAGNOSIS
unknown. PEARLS & CONSIDERATIONS
Diagnostic Overview
RISK FACTORS Diagnosis is made by physical exam. Comments
Administration of progestins or androgens to Examining the penis (exteriorized from the
pregnant dams before sexual differentiation of Differential Diagnosis prepuce) to identify defects such as hypospadias
the external genitalia results in partial mascu- This is a unique disorder. is essential in any case of urinary incontinence
linization (i.e., increased anogenital distance, in puppies.
elongation of the vulva, clitoral hypertrophy). Initial Database
Physical exam Prevention
ASSOCIATED DISORDERS Hypospadias is considered to be a form of
Urine dribbling and scalding, ascending urinary Advanced or Confirmatory Testing male pseudohermaphroditism or sex reversal
tract infection (cystitis) Urinalysis to identify cystitis if present (ascend- in the female and may be heritable. However,
ing infection); urine culture and susceptibility hypospadias can be caused by administra-
Clinical Presentation testing from sample produced by cystocentesis tion of progestins or androgens and certain
DISEASE FORMS/SUBTYPES if evidence of infection is identified teratogens during pregnancy (resulting in female
Subtypes are based on location of urethral pseudohermaphroditism) as well as by feeding
opening: perineal, scrotal, and penile. TREATMENT the dam a diet low in vitamin A. Castration is
recommended unless known steroid adminis-
HISTORY, CHIEF COMPLAINT Treatment Overview tration to the dam during pregnancy can be
Affected animals may show no clinical signs if Treatment is necessary in severe cases to prevent confirmed.
the urethral orifice is located in the distal penis. urine dribbling due to proximal termination
Animals with the urethral orifice terminating of the penile urethra.

HYPOSPADIAS Perineal hypospadias and shortening of the penis. Inguinal region HYPOSPADIAS Severe hypospadias, with the urethral orifice opening as a ventral
of a male dog (cranial is to the top). (Reprinted with permission from Jurka P, et cleft along the entire length of the penis, prepuce, and scrotum. Inguinal region of
al: Hypospadias in six dogs. Vet Rec 164:331-333, 2009.) a male dog (cranial is to the left).

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