Clinical Exposures: A retained testis and spermatic cord torsion in a boxer

A 13-month-old intact male boxer weighing 57.2 lb (26 kg) was presented to the Aristotle University of Thessaloniki Companion Animal Clinic for evaluation of a one-day history of vomiting. The dog's vaccination status was current.

PHYSICAL EXAMINATION AND DIAGNOSTIC TESTING

On physical examination, the dog was bright, alert, and in good body condition. The dog exhibited signs of pain on abdominal palpation, and a firm mass was detected in the caudal abdomen. The scrotum contained only one testis, which was small. Thoracic auscultation revealed a sinus rhythm and a grade III/VI murmur heard best over the pulmonic valve area. The results of a complete blood count, serum chemistry profile, and urinalysis were within reference ranges.

Abdominal radiographs suggested the presence of gas-filled small intestinal loops in the caudal abdomen. An ultrasonographic examination of the caudal abdomen revealed a 5-x-3-cm, oval, coarse, hypoechoic mass surrounded by an echogenic line consistent with an enlarged testis. An elongated structure of the same echogenicity located along the lateral aspect of the mass, consistent with epididymis, was also seen (Figure 1). Color flow Doppler ultrasound revealed an absence of blood flow in the mass. Mild hypomotility of the intestinal loops adjacent to the mass was evident.

1. An abdominal ultrasonogram showing a hypoechoic mass surrounded by an echogenic line consistent with an enlarged testis (T). An elongated structure of the same echogenicity located along the lateral aspect of the mass, consistent with epididymis, is also visualized (E).

Based on clinical and diagnostic imaging findings, we tentatively diagnosed intestinal obstruction or intra-abdominal spermatic cord torsion. Thoracic radiographic and echocardiographic examinations were done to further evaluate the murmur and revealed no abnormalities. A physiologic murmur with no clinical significance was diagnosed.

TREATMENT AND FOLLOW-UP

Surgical exploration of the abdomen was performed on the same day as admission to confirm the diagnosis. The patient received isoflurane anesthesia, and a ventral midline celiotomy was performed.

An enlarged, 5-x-3-cm, dark-red testis was found in the caudal abdomen on the right side with an enlarged spermatic cord; this enlargement was due to 360-degree torsion (Figure 2). The cord was double-ligated with 2-0 polydioxanone, and the testis was removed. Abdominal exploration revealed no other abnormalities, and the celiotomy incision was closed routinely.

2. An enlarged, dark-red, right testis with an enlarged spermatic cord caused by torsion was identified intraoperatively.

The left testis, measuring 3 x 1.5 cm, was also removed by using a standard midline skin incision cranial to the scrotum.

The dog recovered well and was discharged from the hospital two days after surgery. Two years after surgery, the dog was reported to be in good health.

HISTOLOGIC EXAMINATION

Histologic examination of the abdominal testis showed widespread hemorrhages, multifocal coagulative necrosis, and interstitial fibrosis of the tubular structures in the testis and epididymis (Figure 3). An increase in Leydig cell population was present throughout the epididymis, and the tubular epithelium was composed primarily of Sertoli cells. Spermatogonia were sparsely evident in several seminiferous tubules. No signs of neoplasia were found. The histologic findings were compatible with spermatic cord torsion. Histology was not performed on the scrotal testis.

3. A photomicrograph of the right testis showing extensive hemorrhages as well as vascular and fibrous connective tissue proliferation in the interstitial area (F). Note the presence of several degenerated testicular tubules (arrows) showing either edema or coagulative necrosis of the lining epithelium (hematoxylin-eosin stain; bar = 100 µm)

DISCUSSION

In this report, an intra-abdominal-retained testis and spermatic cord torsion were identified in a young boxer. Spermatic cord torsion is relatively uncommon in dogs. Boxers are overrepresented among dogs with spermatic cord torsion, which may reflect the incidence of cryptorchidism in this particular breed.1

CAUSES

As in this case, spermatic cord torsion is more frequently reported with intra-abdominal-retained testes than inguinal-retained or scrotal testes.1,2 It has been hypothesized that the intra-abdominal location of a nonneoplastic or neoplastic testis allows for greater mobility of the testis within the abdominal cavity and may result in spermatic cord torsion.3 After torsion, the nonneoplastic testis enlarges, resulting in venous occlusion, edema, and inflammation.2 Ischemic necrosis, hemorrhage, and edema may be seen histologically in torsion of a nonneoplastic testis.2 However, testicular enlargement may occur before torsion in cases of testicular neoplasia.3 Most reported cases of torsion have occurred in neoplastic testes in which seminoma and Sertoli cell tumors were identified histologically in most of the dogs.1,2

CLINICAL SIGNS AND DIAGNOSIS

Affected animals may present with clinical signs of acute abdomen including a sudden onset of abdominal pain, vomiting, abdominal distention, anorexia, depression, pyrexia, a stiff gait, and abnormalities in urination.1-4 Abdominal palpation may reveal an enlarged mass.

Ultrasonographic examination of the abdomen combined with color flow Doppler may detect a uniform hypoechoic testis and absence of blood flow to and from the affected testis.5,6 Surgical exploration of the abdomen is required to confirm the diagnosis. In this case, ultrasonographic and color flow Doppler findings correlated well with gross and histologic findings.

CONCLUSION

In dogs, spermatic cord torsion is usually an acute situation and should be considered in cases of acute abdomen in cryptorchid dogs.7,8 Differential diagnoses may include intestinal obstruction, an intra-abdominal neoplastic testis, and intra-abdominal spermatic cord torsion. Since cryptorchidism is a heritable defect, treatment includes surgically removing both testes. In a retrospective study of 13 dogs with spermatic cord torsion, 77% survived surgery.1

This case report was provided by Lysimachos G. Papazoglou, DVM, PhD, MRCVS; Michail N. Patsikas, DVM, PhD, DECVDI; Nectarios Soubasis, DVM, PhD; and Vasileia Kouti, DVM, from the Department of Clinical Sciences and Georgia Brellou, DVM, PhD, from the Laboratory of Pathology at the Faculty of Veterinary Medicine, Aristotle University of Thessaloniki, 11 S. Voutyra St., 54627, Thessaloniki, Greece.

REFERENCES

1. Pearson H, Kelly DF. Testicular torsion in the dog: a review of 13 cases. Vet Rec 1975;97:200-204.

2. Naylor RW, Thompson SMR. Intra-abdominal testicular torsion—a report of two cases. J Am Anim Hosp Assoc 1979;15:763-766.

3. Johnston SD, Kustritz MV, Olson PNS. Disorders of the canine testis. In: Johnston SD, Kustritz MV, Olson PNS, eds. Canine and feline theriogenology. Philadelphia, Pa: WB Saunders Co, 2001;312-332.

4. JarlØv N, Blixenkrone-MØller M. Two cases of torsio testis in dogs. Nord Vet Med 1986;38:244-245.

5. Johnston GR, Feeney DA, Rivers B, et al. Diagnostic imaging of the male canine reproductive organs. Methods and limitations. Vet Clin North Am Small Anim Pract 1991;21:553-589.

6. Hecht S, King R, Tidwell AS, et al. Ultrasound diagnosis: intra-abdominal torsion of a non-neoplastic testicle in a cryptorchid dog. Vet Radiol Ultrasound 2004;45:58-61.

7. Flanders JA, Schlafer DH, Yeager AE. Diseases of the canine testes. In: Bonagura JD, ed. Kirk's current veterinary therapy XIII small animal practice. Philadelphia, Pa: WB Saunders Co, 2000;941-947.

8. Bartlett GR. What is your diagnosis? Testicular torsion. J Small Anim Pract 2002;43:521, 551-552.