Nephroureterectomy and Ureteroneocystostomy in an Alpaca With Bilateral Ectopic Ureters Diagnosed by Computed Tomographic Excretory Urography Holly D. Polf, DVM, Diplomate ACVR, Shasta Smith, DVM, Diplomate ACVS, Katharine M. Simpson, DVM, MS, Diplomate ACVIM, and Mark C. Rochat, DVM, MS, Diplomate ACVS Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, Oklahoma
Corresponding Author Holly D. Polf, DVM, Diplomate ACVR, Ally Veterinary Imaging, PO Box 430, Riderwood, MD 21139. E‐mail: [email protected] Submitted September 2013 Accepted March 2014 DOI:10.1111/j.1532-950X.2014.12211.x
Objective: To report diagnosis and treatment of urinary incontinence in a female Huacaya alpaca. Study Design: Clinical case report. Animals: Female intact Huacaya alpaca (n ¼ 1) Methods: Computed tomographic (CT) excretory urography and vaginourethrography were performed to diagnose the cause of urinary incontinence. Results: Bilateral ectopic ureters and left hydronephrosis and hydroureter were diagnosed. Left nephroureterectomy and right ureteroneocystostomy were performed with subsequent resolution of clinical signs. Pyelonephritis was identified by culture of the resected left kidney. Conclusions: CT excretory urography was helpful in the diagnosis of bilateral ectopic ureters in an alpaca and provided information for surgical planning. Surgical repair by ureteroneocystostomy and unilateral nephroureterectomy was successful in resolving clinical signs.
A 6‐month‐old, 28 kg, female Huacaya alpaca (body condition score, 6/10) was referred for evaluation of urinary incontinence, present since 1 week of age. The alpaca reportedly dribbled urine every 15–30 seconds and had never been observed to void a stream of urine. The owners considered the alpaca of comparable size, weight, and body condition score as her age‐matched herd mates. Based on this history, the referring veterinarian suspected an ectopic ureter and referred the alpaca for further evaluation. Food but not water was withheld for 48 hours before referral in anticipation of general anesthesia for diagnostic imaging purposes.
CLINICAL REPORT On admission, the alpaca had urine staining of the fiber on both pelvic limbs and her tail, and mild dermatitis from urine scald ventral to her vulva and extending to the caudomedial aspect of both pelvic limbs. Intermittent urine dribbling without stranguria was observed every 60–90 seconds. Physical examination was otherwise unremarkable and vaginal speculum examination was normal. Mild leukocytosis (12,700/mL [reference interval: 4,900–11,000/mL]) was the only notable hematologic or biochemical abnormality. Given the normal leukocyte differential and morphology, and normal fibrinogen and globulin levels, the significance of this finding was unknown. Complete urinalysis including specific gravity, pH, protein, glucose, ketones, bilirubin, occult blood, and presence
or absence of white and red blood cells, casts, crystals, bacteria, and epithelial cells was performed and was within normal limits. Ultrasonographic evaluation of the urinary tract revealed marked left hydronephrosis and hydroureter. After induction of general anesthesia, computed tomographic (CT; GE Lightspeed; GE Medical Systems, Milwaukee, WI) excretory urography was performed both pre‐ and post‐intravenous (IV) administration of iodinated contrast (400 mgI/kg; Omnipaque1; GE Healthcare, Inc., Princeton, NJ). Hydronephrosis of the left kidney was observed. On the 3 minutes post‐contrast images, contrast could be seen pooling in the gravity‐ dependent portion of the left renal pelvis and, subjectively, was not observed to pass into the left ureter. The left ureter was dilated (1.5 cm diameter proximally and 3.5 cm diameter where it entered the pelvic canal) and bypassed the urinary bladder and terminated 4.5 cm caudal to the neck of the urinary bladder within the pelvic canal. The left ureter was suspected to terminate within the urethra; however, because opacification of the left ureter with contrast was poor it was difficult to determine its termination with certainty. The right ureter measured 2.5 mm proximally. At the level of the neck of the urinary bladder, the right ureter was focally dilated, measuring 7 mm in diameter. The right ureter was identified past the trigone region of the urinary bladder neck and terminated in the proximal urethra just caudal to the neck of the urinary bladder. Contrast pooling within the urinary bladder was suspected to originate from the right ureter because of its termination just past the bladder neck (Figs. 1 and 2).
Veterinary Surgery 44 (2015) 23–26 © Copyright 2014 by The American College of Veterinary Surgeons
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Bilateral Ectopic Ureters in an Alpaca
Polf et al.
Figure 1 A transverse image taken at the level of the left renal hilus 3 minutes post‐contrast administration. Iodinated contrast can be seen pooling in the gravity dependent portion of the dilated left renal pelvis (solid arrow). The left renal cortex is thin. The right ureter (dotted arrow) is visible exiting the right kidney.
Figure 2 A transverse image cranial to the urinary bladder neck obtained 3 minutes post‐contrast administration. The dilated left ureter (solid arrow) is readily visible but is similar in attenuation to the urine within the urinary bladder. The right ureter (dotted arrow) is visible filled with iodinated contrast passing dorsal to the urinary bladder and ventral to the uterine body (arrowhead).
24
To further evaluate the site of termination of the left ureter, a positive‐contrast, retrograde vaginourethrogram was performed after administration of 30 mL of a 50:50 mixture of iodinated contrast (Omnipaque; GE Healthcare, Inc.) and sterile saline solution by Foley catheter, with the balloon placed within the vestibule. Contrast filled the vagina, both uterine horns and, to a lesser degree, the distal urethra. No contrast was seen passing into the left ureter at the level of its termination (Fig. 3). The imaging diagnosis was bilateral ectopic ureters and severe left hydroureter and hydronephrosis. The next day, the alpaca was anesthetized for surgery. On exploratory ventral median celiotomy, the left kidney appeared misshapen and the left ureter was enlarged and tortuous, and passed dorsal to the left uterine horn, adhering to the left side of the uterine body before continuing into the pelvic canal dorsal to the bladder. The left ureter could not be traced to its termination without extensive dissection and pubic osteotomy. Because of the severe hydronephrosis and hydroureter, left nephroureterectomy, using a thoracoabdominal stapler (T/A 30 V stapler, Covidien, Mansfield, MA) was performed (Fig. 4). A ventral median cystotomy was performed and no ureteral openings were observed; however, urine could be observed flowing retrograde from the urethra towards the cystotomy. The right ureter was identified by a combination of digital palpation and knowledge of the ureter’s normal anatomic pathway between the kidney and bladder, and isolated from the adjacent peritoneum and retroperitoneal fat by blunt dissection. The right ureter was traced as it passed dorsal to the right uterine horn and bladder before continuing caudal and dorsal to
Figure 3 A sagittal reconstruction of the pelvic canal obtained following vaginourethrogram. The right ureter (dotted arrow) appears to terminate just caudal to the bladder neck within the urethra. The dilated left ureter (solid arrow) is visible dorsal to the urethra. The contrast filled vagina and uterus are partially visible (arrowhead).
Veterinary Surgery 44 (2015) 23–26 © Copyright 2014 by The American College of Veterinary Surgeons
Polf et al.
Bilateral Ectopic Ureters in an Alpaca
11 days after surgery with instructions to administer ceftiofur crystalline free acid (6.6 mg/kg subcutaneously once every 3 days for a total of three doses; Excede1, Pfizer, New York, NY). Eight months after surgery, the owner had not observed any complications as a result of unilateral nephrectomy and ureteroneocystostomy and the alpaca is continent.
DISCUSSION
Figure 4 Image of the left kidney and ureter sectioned in the dorsal plane at the level of the renal hilus following surgical removal. The dilated renal pelvis (dotted arrow) and left ureter (solid arrow) are visible.
the bladder and urethra into the pelvic canal. As with the left ureter, the right ureter could not be traced to its termination without extensive dissection and pubic osteotomy. The right ureter was transected at the most distal level accessible and the distal ureteral stump ligated. A right ureteroneocystostomy was performed using loupe magnification and a headlamp. The transected end of the ureter was passed through a straight stab incision in the caudal part of the dorsolateral aspect of the bladder. The ureteral end was trimmed to healthy tissues, spatulated by incising the ureter longitudinally 3 mm with fine‐ tipped scissors, and suturing the spatulated ureter to the adjacent bladder mucosa and submucosa with interrupted 6–0 polydioxanone sutures. Morphologic findings within the left kidney included marked suppurative pyelonephritis with renal pelvic ectasia, medullary atrophy, interstitial fibrosis, and suppurative and lymphoplasmacytic nephritis. Changes in the left ureter were consistent with marked hydroureter and marked suppurative and lymphoplasmacytic ureteritis with mucosal hyperplasia and segmental ulceration. Microbial culture of the left renal pelvis yielded growth of Enterococcus faecalis susceptible to ampicillin and penicillin. The alpaca recovered without complication from surgery and was administered ceftiofur (5 mg/kg IV every 12 hours), and potassium penicillin (22,000 U/kg slowly IVevery 6 hours) for pyelonephritis while hospitalized. Broad‐spectrum bactericidal antimicrobial therapy was used empirically based on gross appearance of the left kidney after ureteronephrectomy, because histopathology and microbial culture results were not immediately available. Butorphanol tartrate (0.1 mg/kg subcutaneously every 6 hours) and flunixin meglumine (1.1 mg/kg once daily IV for 3 days) were administered for pain analgesia. Urinary incontinence resolved completely post‐operatively. Antimicrobial therapy was continued for an extended period after surgery because of potential for ascending pyelonephritis of the remaining kidney; however, there were no clinical signs of residual or ascending infection. The alpaca was discharged
Use of CT excretory urography for diagnosis of ectopic ureters has been reported in dogs1–3 and a llama.4 Because it provides cross‐sectional images, CT offers the advantage of improved anatomic information. Compared with excretory urography performed with radiographs or fluoroscopy, CT allows the ureters to be identified without superimposition of other anatomic structures. In dogs, the correlation of CT excretory urography for the diagnosis of ureteral ectopia with surgical and necropsy findings is better than the correlation of other imaging modalities, including excretory urography with radiographs and urethrography with surgical and necropsy findings3; CT has a sensitivity of 91% and a specificity of 100% for detection of ureteral ectopia when compared to surgery or necropsy as the gold standard.3 Given the lack of contrast filling of the left ureter, CT was critical in this case to identify the left ureter, which would not have been possible on radiographs because of summation and silhouetting with surrounding structures. Congenital defects of the urinary system are relatively rare in camelids, and accounted for only 1.6% of all reported congenital defects in llamas.5 Unilateral6 and bilateral renal agenesis,7 and ureteral duplication8 have been described in camelids. Unilateral ectopic ureter has been reported in a llama,4 but bilateral ureteral ectopia and ureteroneocystostomy have not been described in camelids. Hydroureter is a common finding in dogs with ectopic ureter9 and was described in the llama case report.4 Although normal ureteral diameter on excretory urography is not reported in the alpaca, the left ureter and distal right ureter in this case were presumed dilated based on published normal values in dogs.2 The severe left hydroureter in this alpaca may have occurred secondary to altered ureteral peristalsis as a result of the suppurative and lymphoplasmacytic ureteritis or failure of the neuromuscular function of the ureter to develop properly. Hydroureter may also have occurred as a result of a partial obstruction at the site of the distal termination of the ureter or, less likely, a blind‐ ended ureter. Some degree of left ureteral obstruction is suspected given the normal urinalysis findings at admission. Altered ureteral peristalsis may have also contributed to the poor pyelogram phase of the excretory urogram. Although the precise location of termination of the ureters was not identified at surgery, urine was observed entering the urinary bladder from the bladder neck or urethra at surgery, indicating that at least the right ureter and possibly both ureters terminated within the urethra. A pubic osteotomy would have been required to locate the distal aspect of the ureters and was not performed to avoid incurring unnecessary morbidity. Although not used, pre‐operative vaginoscopy, cystoscopy,
Veterinary Surgery 44 (2015) 23–26 © Copyright 2014 by The American College of Veterinary Surgeons
25
Bilateral Ectopic Ureters in an Alpaca
Polf et al.
and/or urethroscopy is considered extremely useful in diagnosing ureteral ectopia and the precise point of terminal entry of the ureters in dogs,3 and would have likely assisted in determining the termination of the left ureter in this alpaca. Regardless that the exact location of the ureters was not confirmed, contrast CT was useful for diagnosis and surgical planning. We documented successful treatment of bilateral ectopic ureters with unilateral pyelonephritis in an alpaca with unilateral ureteroneocystostomy and unilateral nephroureterectomy, respectively.
as assessed by computed tomography. Vet Radiol Ultrasound 1998;39:524–527 2. Rozear L, Tidwell AS: Evaluation of the ureter and ureterovesicular junction using helical computed tomographic excretory urography in healthy dogs. Vet Radiol Ultrasound 2003;44:155–164 3. Samii VF, McLoughlin MA, Mattoon JS, et al: Digital fluoroscopic excretory urography, digital fluoroscopic urethrography, helical computed tomography, and cystoscopy in 24 dogs with suspected ureteral ectopia. J Vet Intern Med 2004;18:271–281 4. Van Hoogmoed L, Snyder J, Roberts G, et al: Unilateral nephrectomy in a juvenile llama. Veterinary Surgery 1997;26: 497–501
DISCLOSURE
5. Leipold HW, Hiraga T, Johnson LW: Congenital defects in the llama. Vet Clin North Am: Food Anim Pract 1994;10:401–420
The authors declare no financial or other conflicts of interest related to this report.
6. Hardefeldt LY, Textor JA, Dart AJ: Renal agenesis in an alpaca cria. Aust Vet J 2007;85:185–187 7. Poulsen KP, Gerard MP, Spaulding KA, et al: Bilateral renal agenesis in an alpaca cria. Can Vet J 2006;47:159–161
REFERENCES
8. Cardwell JM, Thorne MH: Hydronephrosis and ureteral duplication in a young alpaca. Vet Rec 1999;145:104–107
1. Barthez PY, Begon D, Delisle F: Effect of contrast medium dose and image acquisition timing on ureteral opacification in the normal dog
9. Holt PE, Gibbs C, Pearson H: Canine ectopic ureter—a review of twenty‐nine cases. J Small Anim Pract 1982;23:195–208
26
Veterinary Surgery 44 (2015) 23–26 © Copyright 2014 by The American College of Veterinary Surgeons
Corresponding Author Holly D. Polf, DVM, Diplomate ACVR, Ally Veterinary Imaging, PO Box 430, Riderwood, MD 21139. E‐mail: [email protected] Submitted September 2013 Accepted March 2014 DOI:10.1111/j.1532-950X.2014.12211.x
Objective: To report diagnosis and treatment of urinary incontinence in a female Huacaya alpaca. Study Design: Clinical case report. Animals: Female intact Huacaya alpaca (n ¼ 1) Methods: Computed tomographic (CT) excretory urography and vaginourethrography were performed to diagnose the cause of urinary incontinence. Results: Bilateral ectopic ureters and left hydronephrosis and hydroureter were diagnosed. Left nephroureterectomy and right ureteroneocystostomy were performed with subsequent resolution of clinical signs. Pyelonephritis was identified by culture of the resected left kidney. Conclusions: CT excretory urography was helpful in the diagnosis of bilateral ectopic ureters in an alpaca and provided information for surgical planning. Surgical repair by ureteroneocystostomy and unilateral nephroureterectomy was successful in resolving clinical signs.
A 6‐month‐old, 28 kg, female Huacaya alpaca (body condition score, 6/10) was referred for evaluation of urinary incontinence, present since 1 week of age. The alpaca reportedly dribbled urine every 15–30 seconds and had never been observed to void a stream of urine. The owners considered the alpaca of comparable size, weight, and body condition score as her age‐matched herd mates. Based on this history, the referring veterinarian suspected an ectopic ureter and referred the alpaca for further evaluation. Food but not water was withheld for 48 hours before referral in anticipation of general anesthesia for diagnostic imaging purposes.
CLINICAL REPORT On admission, the alpaca had urine staining of the fiber on both pelvic limbs and her tail, and mild dermatitis from urine scald ventral to her vulva and extending to the caudomedial aspect of both pelvic limbs. Intermittent urine dribbling without stranguria was observed every 60–90 seconds. Physical examination was otherwise unremarkable and vaginal speculum examination was normal. Mild leukocytosis (12,700/mL [reference interval: 4,900–11,000/mL]) was the only notable hematologic or biochemical abnormality. Given the normal leukocyte differential and morphology, and normal fibrinogen and globulin levels, the significance of this finding was unknown. Complete urinalysis including specific gravity, pH, protein, glucose, ketones, bilirubin, occult blood, and presence
or absence of white and red blood cells, casts, crystals, bacteria, and epithelial cells was performed and was within normal limits. Ultrasonographic evaluation of the urinary tract revealed marked left hydronephrosis and hydroureter. After induction of general anesthesia, computed tomographic (CT; GE Lightspeed; GE Medical Systems, Milwaukee, WI) excretory urography was performed both pre‐ and post‐intravenous (IV) administration of iodinated contrast (400 mgI/kg; Omnipaque1; GE Healthcare, Inc., Princeton, NJ). Hydronephrosis of the left kidney was observed. On the 3 minutes post‐contrast images, contrast could be seen pooling in the gravity‐ dependent portion of the left renal pelvis and, subjectively, was not observed to pass into the left ureter. The left ureter was dilated (1.5 cm diameter proximally and 3.5 cm diameter where it entered the pelvic canal) and bypassed the urinary bladder and terminated 4.5 cm caudal to the neck of the urinary bladder within the pelvic canal. The left ureter was suspected to terminate within the urethra; however, because opacification of the left ureter with contrast was poor it was difficult to determine its termination with certainty. The right ureter measured 2.5 mm proximally. At the level of the neck of the urinary bladder, the right ureter was focally dilated, measuring 7 mm in diameter. The right ureter was identified past the trigone region of the urinary bladder neck and terminated in the proximal urethra just caudal to the neck of the urinary bladder. Contrast pooling within the urinary bladder was suspected to originate from the right ureter because of its termination just past the bladder neck (Figs. 1 and 2).
Veterinary Surgery 44 (2015) 23–26 © Copyright 2014 by The American College of Veterinary Surgeons
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Bilateral Ectopic Ureters in an Alpaca
Polf et al.
Figure 1 A transverse image taken at the level of the left renal hilus 3 minutes post‐contrast administration. Iodinated contrast can be seen pooling in the gravity dependent portion of the dilated left renal pelvis (solid arrow). The left renal cortex is thin. The right ureter (dotted arrow) is visible exiting the right kidney.
Figure 2 A transverse image cranial to the urinary bladder neck obtained 3 minutes post‐contrast administration. The dilated left ureter (solid arrow) is readily visible but is similar in attenuation to the urine within the urinary bladder. The right ureter (dotted arrow) is visible filled with iodinated contrast passing dorsal to the urinary bladder and ventral to the uterine body (arrowhead).
24
To further evaluate the site of termination of the left ureter, a positive‐contrast, retrograde vaginourethrogram was performed after administration of 30 mL of a 50:50 mixture of iodinated contrast (Omnipaque; GE Healthcare, Inc.) and sterile saline solution by Foley catheter, with the balloon placed within the vestibule. Contrast filled the vagina, both uterine horns and, to a lesser degree, the distal urethra. No contrast was seen passing into the left ureter at the level of its termination (Fig. 3). The imaging diagnosis was bilateral ectopic ureters and severe left hydroureter and hydronephrosis. The next day, the alpaca was anesthetized for surgery. On exploratory ventral median celiotomy, the left kidney appeared misshapen and the left ureter was enlarged and tortuous, and passed dorsal to the left uterine horn, adhering to the left side of the uterine body before continuing into the pelvic canal dorsal to the bladder. The left ureter could not be traced to its termination without extensive dissection and pubic osteotomy. Because of the severe hydronephrosis and hydroureter, left nephroureterectomy, using a thoracoabdominal stapler (T/A 30 V stapler, Covidien, Mansfield, MA) was performed (Fig. 4). A ventral median cystotomy was performed and no ureteral openings were observed; however, urine could be observed flowing retrograde from the urethra towards the cystotomy. The right ureter was identified by a combination of digital palpation and knowledge of the ureter’s normal anatomic pathway between the kidney and bladder, and isolated from the adjacent peritoneum and retroperitoneal fat by blunt dissection. The right ureter was traced as it passed dorsal to the right uterine horn and bladder before continuing caudal and dorsal to
Figure 3 A sagittal reconstruction of the pelvic canal obtained following vaginourethrogram. The right ureter (dotted arrow) appears to terminate just caudal to the bladder neck within the urethra. The dilated left ureter (solid arrow) is visible dorsal to the urethra. The contrast filled vagina and uterus are partially visible (arrowhead).
Veterinary Surgery 44 (2015) 23–26 © Copyright 2014 by The American College of Veterinary Surgeons
Polf et al.
Bilateral Ectopic Ureters in an Alpaca
11 days after surgery with instructions to administer ceftiofur crystalline free acid (6.6 mg/kg subcutaneously once every 3 days for a total of three doses; Excede1, Pfizer, New York, NY). Eight months after surgery, the owner had not observed any complications as a result of unilateral nephrectomy and ureteroneocystostomy and the alpaca is continent.
DISCUSSION
Figure 4 Image of the left kidney and ureter sectioned in the dorsal plane at the level of the renal hilus following surgical removal. The dilated renal pelvis (dotted arrow) and left ureter (solid arrow) are visible.
the bladder and urethra into the pelvic canal. As with the left ureter, the right ureter could not be traced to its termination without extensive dissection and pubic osteotomy. The right ureter was transected at the most distal level accessible and the distal ureteral stump ligated. A right ureteroneocystostomy was performed using loupe magnification and a headlamp. The transected end of the ureter was passed through a straight stab incision in the caudal part of the dorsolateral aspect of the bladder. The ureteral end was trimmed to healthy tissues, spatulated by incising the ureter longitudinally 3 mm with fine‐ tipped scissors, and suturing the spatulated ureter to the adjacent bladder mucosa and submucosa with interrupted 6–0 polydioxanone sutures. Morphologic findings within the left kidney included marked suppurative pyelonephritis with renal pelvic ectasia, medullary atrophy, interstitial fibrosis, and suppurative and lymphoplasmacytic nephritis. Changes in the left ureter were consistent with marked hydroureter and marked suppurative and lymphoplasmacytic ureteritis with mucosal hyperplasia and segmental ulceration. Microbial culture of the left renal pelvis yielded growth of Enterococcus faecalis susceptible to ampicillin and penicillin. The alpaca recovered without complication from surgery and was administered ceftiofur (5 mg/kg IV every 12 hours), and potassium penicillin (22,000 U/kg slowly IVevery 6 hours) for pyelonephritis while hospitalized. Broad‐spectrum bactericidal antimicrobial therapy was used empirically based on gross appearance of the left kidney after ureteronephrectomy, because histopathology and microbial culture results were not immediately available. Butorphanol tartrate (0.1 mg/kg subcutaneously every 6 hours) and flunixin meglumine (1.1 mg/kg once daily IV for 3 days) were administered for pain analgesia. Urinary incontinence resolved completely post‐operatively. Antimicrobial therapy was continued for an extended period after surgery because of potential for ascending pyelonephritis of the remaining kidney; however, there were no clinical signs of residual or ascending infection. The alpaca was discharged
Use of CT excretory urography for diagnosis of ectopic ureters has been reported in dogs1–3 and a llama.4 Because it provides cross‐sectional images, CT offers the advantage of improved anatomic information. Compared with excretory urography performed with radiographs or fluoroscopy, CT allows the ureters to be identified without superimposition of other anatomic structures. In dogs, the correlation of CT excretory urography for the diagnosis of ureteral ectopia with surgical and necropsy findings is better than the correlation of other imaging modalities, including excretory urography with radiographs and urethrography with surgical and necropsy findings3; CT has a sensitivity of 91% and a specificity of 100% for detection of ureteral ectopia when compared to surgery or necropsy as the gold standard.3 Given the lack of contrast filling of the left ureter, CT was critical in this case to identify the left ureter, which would not have been possible on radiographs because of summation and silhouetting with surrounding structures. Congenital defects of the urinary system are relatively rare in camelids, and accounted for only 1.6% of all reported congenital defects in llamas.5 Unilateral6 and bilateral renal agenesis,7 and ureteral duplication8 have been described in camelids. Unilateral ectopic ureter has been reported in a llama,4 but bilateral ureteral ectopia and ureteroneocystostomy have not been described in camelids. Hydroureter is a common finding in dogs with ectopic ureter9 and was described in the llama case report.4 Although normal ureteral diameter on excretory urography is not reported in the alpaca, the left ureter and distal right ureter in this case were presumed dilated based on published normal values in dogs.2 The severe left hydroureter in this alpaca may have occurred secondary to altered ureteral peristalsis as a result of the suppurative and lymphoplasmacytic ureteritis or failure of the neuromuscular function of the ureter to develop properly. Hydroureter may also have occurred as a result of a partial obstruction at the site of the distal termination of the ureter or, less likely, a blind‐ ended ureter. Some degree of left ureteral obstruction is suspected given the normal urinalysis findings at admission. Altered ureteral peristalsis may have also contributed to the poor pyelogram phase of the excretory urogram. Although the precise location of termination of the ureters was not identified at surgery, urine was observed entering the urinary bladder from the bladder neck or urethra at surgery, indicating that at least the right ureter and possibly both ureters terminated within the urethra. A pubic osteotomy would have been required to locate the distal aspect of the ureters and was not performed to avoid incurring unnecessary morbidity. Although not used, pre‐operative vaginoscopy, cystoscopy,
Veterinary Surgery 44 (2015) 23–26 © Copyright 2014 by The American College of Veterinary Surgeons
25
Bilateral Ectopic Ureters in an Alpaca
Polf et al.
and/or urethroscopy is considered extremely useful in diagnosing ureteral ectopia and the precise point of terminal entry of the ureters in dogs,3 and would have likely assisted in determining the termination of the left ureter in this alpaca. Regardless that the exact location of the ureters was not confirmed, contrast CT was useful for diagnosis and surgical planning. We documented successful treatment of bilateral ectopic ureters with unilateral pyelonephritis in an alpaca with unilateral ureteroneocystostomy and unilateral nephroureterectomy, respectively.
as assessed by computed tomography. Vet Radiol Ultrasound 1998;39:524–527 2. Rozear L, Tidwell AS: Evaluation of the ureter and ureterovesicular junction using helical computed tomographic excretory urography in healthy dogs. Vet Radiol Ultrasound 2003;44:155–164 3. Samii VF, McLoughlin MA, Mattoon JS, et al: Digital fluoroscopic excretory urography, digital fluoroscopic urethrography, helical computed tomography, and cystoscopy in 24 dogs with suspected ureteral ectopia. J Vet Intern Med 2004;18:271–281 4. Van Hoogmoed L, Snyder J, Roberts G, et al: Unilateral nephrectomy in a juvenile llama. Veterinary Surgery 1997;26: 497–501
DISCLOSURE
5. Leipold HW, Hiraga T, Johnson LW: Congenital defects in the llama. Vet Clin North Am: Food Anim Pract 1994;10:401–420
The authors declare no financial or other conflicts of interest related to this report.
6. Hardefeldt LY, Textor JA, Dart AJ: Renal agenesis in an alpaca cria. Aust Vet J 2007;85:185–187 7. Poulsen KP, Gerard MP, Spaulding KA, et al: Bilateral renal agenesis in an alpaca cria. Can Vet J 2006;47:159–161
REFERENCES
8. Cardwell JM, Thorne MH: Hydronephrosis and ureteral duplication in a young alpaca. Vet Rec 1999;145:104–107
1. Barthez PY, Begon D, Delisle F: Effect of contrast medium dose and image acquisition timing on ureteral opacification in the normal dog
9. Holt PE, Gibbs C, Pearson H: Canine ectopic ureter—a review of twenty‐nine cases. J Small Anim Pract 1982;23:195–208
26
Veterinary Surgery 44 (2015) 23–26 © Copyright 2014 by The American College of Veterinary Surgeons
