Treatment of clitoral hypertrophy containing an os clitoris and urethra in a young greyhound dog: A detailed surgical description

Abstract

This report provides a detailed description and images of a clitorectomy with a urethral transposition. As described, the clitorectomy is a straight-forward procedure, creating more normal female-like anatomy, and it resolves the clinical signs resulting from the exposed clitoris.

When abnormal clitoral development results in enlargement or development of male-like characteristics, the condition is called clitoral hypertrophy. With this condition, the sensitive enlarged clitoris protrudes outside the vulvar labia, resulting in chronic irritation, licking, and mucoid to mucopurulent vulvar discharge. Surgery is indicated if these clinical signs exist, and the clitoris does not shrink following withdrawal of concurrent hormone administration (acquired clitoral hypertrophy), anti-inflammatory agents and antibiotics, or when the clitoris contains an os clitoris or urethra due to an intersex abnormality (congenital clitoral hypertrophy). There is scant information available in the literature that fully describes surgical excision of the clitoris (clitorectomy). Most current veterinary texts provide only brief general descriptions of the procedure (1–5). We found 1 case report of a dog undergoing surgical excision of the clitoris; however, the enlarged clitoris in this case did not contain a urethra (6). The case described herein involves a novel surgical treatment of a dog with a large clitoris containing both an os clitoris and urethra.

The purpose of this case report is to provide a detailed description and images of a successful clitorectomy technique to help guide inexperienced surgeons interested in performing this procedure.

Case description

A 2-year-old female spayed greyhound dog was presented to Colorado State University Veterinary Teaching Hospital (CSUVTH) with a history of local pain, irritation, enlargement, and mucoid discharge in the vulvar region. The dog had been adopted from a rescue operation 4 mo prior to presentation, and the owners reported that the condition had been present since adoption. The condition did not change despite empirical antibiotic trials, and elimination of self-trauma with an Elizabethan collar. The dog was referred to the soft tissue service for surgical consultation and possible surgical correction. According to the records from the referring veterinarian, there were no reported abnormalities in the reproductive tract of the dog noted at the time of ovariohysterectomy, which was done prior to the adoption. The exact time of the sterilization procedure was unknown. According to the owners, there were no signs of hematuria or stranguria during the time that they owned the dog.

Physical examination revealed a protruding, enlarged clitoris, and moderate inflammation of the surrounding tissues. The clitoris protruded from the vaginal opening approximately 1.5 cm. An os clitoris was palpated within the protruding clitoris, which measured 4 cm in length. A urethral groove extended from the base of the os clitoris to around three-quarters the distance to the distal clitoral tip. No other abnormalities were evident on vaginal and rectal palpation. A prior caudal midline abdominal scar was visible from the previous sterilization procedure. There were no other physical examination abnormalities with the exception of symmetrical alopecia of both caudal thighs (considered a pattern baldness in this breed), and a small dermal ulcer of unknown etiology.

Hematological analysis revealed a mild leukopenia [3.1 × 10³/μL, reference range (RR): 4.0 to 15.5 × 10³/μL] and a mild thrombocytopenia (160 × 10³/μL, RR: 170 to 400 × 10³/μL) of unknown etiology. Serum biochemical analysis revealed no abnormalities. The packed cell volume (54%, RR: 36% to 60%) and total protein (53 g/L, RR: 50 to 74 g/L) were within normal range.

Surgical procedure

Prior to surgery the dog was given hydromorphone (Dilaudid; Knoll Parma, Markham, Ontario), 0.1 mg/kg body weight (BW), SQ, and midazolam hydrochloride (Versed; Roche Pharmaceuticals, Nutley, New Jersey, USA), 0.25 mg/kg BW, SQ, and acetylpromazine maleate (Acepromazine Maleate; Vedco, St. Joseph, Missouri, USA), 0.01 mg/kg BW, IV. Anesthesia was induced with propofol (PropoFlo; Abbott, North Chicago, Illinois, USA), 3.15 mg/kg BW, IV, and maintained with isoflurane (Isoflurane; Vet One, MWI Veterinary Supply, Boise, Idaho, USA) and oxygen. Just prior to the procedure, cefazolin (Cefazolin Sodium; Marsam Pharmaceuticals, Cherry Hill, New Jersey, USA), 22 mg/kg BW, was administered intravenously. Morphine (Duramorph; Baxter, Deerfield, Illinois, USA), 0.1 mg/kg BW and bupivacaine hydrochloride (Marcaine, Abbott, Abbott Park, Illinois, USA), 0.53 mg/kg BW, were injected as an epidural in the lumbosacral space, and carprofen (Rimadyl; Pfizer, New York, New York, USA), 2.2 mg/kg BW, was injected subcutaneously.

The dog was placed in ventral recumbency in a Trendelenberg position with hind limbs hanging over a padded end of the surgery table (Figure 1). The tail was taped and fixed over the dog’s back exposing the perineum. A purse-string suture using 2-0 nylon (Monosof; Covidien, Mansfield, Massachusetts, USA) was placed in the anus, and the entire perineum was routinely prepared for aseptic surgery (Figure 2).

Figure 1.

Patient in Trendelenberg position. Note the mucoid discharge dripping from the vulva.

Figure 2.

Aseptic preparation of surgical site.

A 3-cm episiotomy was performed in the skin dorsal to the vulva with unipolar electrotomy (Force FX; Valleylab, Boulder, Colorado, USA) to expose the clitoris and vulvar vault. Nylon (2-0) stay sutures (Monosof, Covidien) were placed in the skin on either side of the episiotomy incision, and clitoris (Figure 3).

Figure 3.

Exposure of vaginal vault via an episiotomy.

The urethral orifice followed a groove that was identified on the distodorsal aspect of the body of the clitoris. Two stay sutures were then placed, 1 at the distal tip of the clitoris, and the other at the distal aspect of the urethral groove to facilitate atraumatic manipulation of these structures. The distal urethral groove was dissected from the entire length of the clitoris with electrotomy (Figure 4). Very little hemorrhage was evident during this urethral dissection. The incision was carried along a distinct line between the urethral and clitoral mucosa until it extended past the base of the clitoris (Figure 5).

Figure 4.

Dissection of urethral plate from the clitoris.

Figure 5.

Completion of urethral dissection to the base of the os clitoris.

The junction of the vulvar mucosa and clitoral mucosa was incised with electrotomy around the base of the clitoris (Figure 6). The base of the clitoris was amputated at the zone of transition between the clitoral and vaginal mucosa using unipolar electrocoagulation. Alternating incisions were made between the left and right hand side of the clitoral base, through the attachments of the clitoris to the ischium. The paired clitoral arteries were electrocoagulated and hemostasis was readily achieved (Figure 7). After establishing that the urethra remained patent with a urinary catheter, the urethral groove edges were closed to the clitoral fossa mucosa with interrupted 4-0 polyglytone 6211 sutures (Caprosyn, Covidien). This established a more normal urethra and vulvar conformation (Figure 8).

Figure 6.

Completion of os clitoris excision at base of clitoral fossa.

Figure 7.

The clitoris has been completely excised showing defect remaining in vulvar floor.

Figure 8.

Closure of urethral plate to mucosa of clitoral fossa.

To begin closure of the episiotomy, the incised vulvar mucosa was closed with a 4-0 glycomer 631 suture (Biosyn, Covidien) in a simple continuous pattern (Figure 9). The subcutaneous layer and constrictor vulvae muscles were closed together in a similar fashion. Skin was closed with a continuous intradermal pattern using 4-0 glycomer 631 (Biosyn, Covidien) (Figure 10). Carprofen (Rimadyl, Pfizer), 2.2 mg/kg BW, SQ, was administered before recovery from anesthesia.

Figure 9.

Closure of vulvar mucosa during repair of episiotomy.

Figure 10.

Completed closure of episiotomy.

Postoperative course

The dog recovered from anesthesia uneventfully, and rested comfortably until release from the hospital the following morning. At that time the dog was ambulating normally, and urinated with no signs of discomfort. The wound had minimal inflammation and no bleeding was noted. Oral tramadol hydrochloride (Ultram; Janssen, Titusville, New Jersey, USA), 3.5 mg/kg BW, q8h, and carprofen (Rimadyl, Pfizer), 1.75 mg/kg BW, q12h, were prescribed for the following 5 days. The owners were instructed to restrict activity to short walks on a leash, to ice-pack the wound 3 times daily, and to keep the Elizabethan collar on the dog until a recheck scheduled 2 wk from surgery. At that time the wound had healed and there was no evidence of pain or bleeding from the vulva.

The owners, however, did notice that the dog had pollakiuria and some blood at the end of urination. A urine sample obtained via cystocentesis was analyzed and submitted for culture and susceptibility. A urinary tract infection was diagnosed and the culture results showed growth of Proteus mirabilis. Amoxicillin/clavulanic acid (Clavamox; SmithKline Beecham, West Chester, Pennsylvania, USA), 13.2 mg/kg BW, PO, q12h for 12 d was prescribed for the infection. At the 2-week recheck, the urinary tract infection and hematuria had resolved, with the culture results showing no growth. At 9 wk after surgery, the owners reported that the dog was doing well with no complications.

Discussion

Embryologically, the clitoris in female dogs and penis in male dogs develop from a common site, the genital tubercle. During sexual development, the clitoris does not normally contain any structures comparable to the os penis, the corpus cavernosum urethra or the urethra, although the body of the normal clitoris does contain cavernous erectile tissue like the penis. Abnormalities in clitoral development occur from various intersex conditions caused by altered chromosome differentiation, from exposure to androgens or progestins during gestation, by exogenous androgen administration early after birth, and hyperadrenocortism.

Congenital clitoral abnormalities have been reported in American and English cocker spaniels, beagles, Weimaraners, Kerry blue terriers, and pug breeds. At fertilization, sex chromosomes are normally established as XX (female) or XY (male). Errors that occur during meiosis can result in abnormal sex chromosome combinations. The abnormal sex chromosomes can cause disorders of sexual development of various degrees of severity and type. Many result in abnormal reproductive anatomy, and the dogs are usually sterile. Bitches that present with congenital clitoral hypertrophy often have disorders of gonadal sex, where the gonadal sex does not agree with the chromosomal sex. This is categorized as XX sex reversal, and the mode of inheritance is uncertain, but in the American cocker spaniel it is inherited as an autosomal recessive trait (1). Acquired abnormalities in clitoral development can be caused by exogenous androgen exposure during fetal development or early after birth, or by the administration of androgens. Hyperadrenocorticism is also reported to cause clitoral hypertrophy (1–4). On rare occasions the adrenal glands can produce hyperadrenocorticism leading to clitoral hypertrophy in female dogs, testicular atrophy in intact males, or prostatomegaly in castrated males (7,8). The presence of an os clitoris in the subject of this case report was likely due to an acquired clitoral hypertrophy, resulting from the effects of methyltestosterone. The use of androgens is very common in racing greyhounds to suppress the estrus cycle and to increase muscle mass (9). The administration of this male hormone probably resulted in the masculinization of the clitoris in this dog.

The surgery procedure described here was designed to preserve the entire length of the urethra so it could be positioned in the defect resulting from removal of the hypertrophied clitoris. It was felt that preservation of the entire urethral length would help reduce any risk of stricture formation. The urethra was transpositioned over the defect and this helped to reduce narrowing of the distal vaginal vault. If the urethral drain board was excised instead, apposition of the vulvar mucosa on either side of the defect without transposing the urethra might constrict the distal vulvar area, possibly reducing drainage from the tract. Removal of the urethral groove from the dorsal aspect of the clitoris first enabled full exposure of the base of the clitoris and os clitoris, to facilitate excision of this structure from underlying attachments. Removal and retraction of the urethra from the clitoris also helped expose the paired clitoral arteries entering the proximal base of the clitoris. The episiotomy additionally helped expose the base of the clitoris and urethra. The procedure may be performed without an episiotomy if assistants are available to help retract the vulvar opening dorsally. Hemorrhage was readily controlled with unipolar electrocoagulation, and resecting the clitoral base close to its pelvic attachment minimized bleeding. Excision at the attachments helps reduce bleeding by avoiding breach of the clitoral cavernous tissues.

This case report provides a detailed description and images of a clitorectomy with a urethral transposition. The clitorectomy is simple to perform, creating more normal female anatomy and resolves the clinical signs resulting from the exposed clitoris. There were no surgically related complications resulting from this procedure at the 9-week follow-up. CVJ