A 3 year old male Weimaraner presented to the emergency service for a 12 hour history of lethargy and not eating breakfast, both of which are very uncharacteristic. The dog may have vomited but this could not be confirmed.
This dog had undergone an intra-abdominal vasectomy 3 years ago at the same time as repair of a peritoneal-pericardial diaphragmatic hernia. Because the vas deferens was not isolated using an inguinal incision, the midline abdominal incision was extended caudally. The vas deferens was reportedly transected with ligation of both ends of both the right and left vas deferens.
Abdominal radiographs were acquired:
Questions for discussion after reviewing images:
What are the radiographic findings and conclusions?
What is the origin of the lesion and what organ(s) are involved?
What additional imaging if any is recommended?
What additional treatment if any is recommended?
- There are wispy soft tissue opacities along the ventral abdomen with mildly reduced serosal detail and contrast, consistent with a small volume of peritoneal fluid.
- The stomach contains a small amount of gas which fills the pylorus in the left lateral projection; there is no evidence of gastric foreign material.
- The small intestines are of a single uniform population without evidence of mechanical obstruction.
- Within the left mid-abdomen there is a loop of intestine in the plane of the colon with serial curvilinear soft tissue opacities thought to represent intestinal folds as this is not identified in other projections.
- Neither the duodenum nor colon is clearly identified in the VD projection although there is subjective mass effect in the region of the pancreas deviating gas filled bowel loops around it non-specific for, but suggestive of pancreatitis.
- There are linear to curvilinear segments of mineral opacity superimposed with the plane of the membranous urethra that is not triangulated in the VD projection. Urethral mineralization or peripheral soft tissue dystrophic mineralization are both possible but the significance is unknown.
- The urinary bladder is displaced cranially by a large, smoothly marginated prostate gland without evidence of mineralization which is likely normal for a hormonally intact male dog.
- There are two smoothly rounded mineral opacities at the level of the site of prepubic tendon insertion on the prepubic eminence. These are most consistent with prepubic tendon sesamoid bones, a normal variant. These may also represent the caudal pair of nipples.
Based primarily on the presence of abdominal fluid and a possible mass in the region of the prostate gland, an abdominal ultrasound examination was performed.
- There is a small to moderate volume of mildly echogenic peritoneal fluid. There is anechoic urine in the adjacent urinary bladder.
- The prostate gland is symmetrically enlarged, measuring 5.5cm in lateral diameter. The prostate gland is homogeneously solid with no evidence of cysts or cavitations. Most likely this is benign hypertrophy.
- Along the dorsal aspect of the left testis, there is an anechoic tubular structure that becomes a tortuous sigmoidal plexus caudally. Most of this plexus does not have blood flow when interrogated with Doppler, but there are peripheral vessels adjacent to the larger ducts. The head of the epididymis is normal. This is suspected to represent a dilated ductus deferens that extends into the epididymis.
- The right peri-testicular structures are more normal than the left however there is still subjective mild distention of tubular tortuous structures medial to the testis, but the large dorsal enlargement seen on the left is not present on the right.
- The liver, gallbladder, spleen, kidneys, adrenal glands (L:0.43cm R: 0.6cm), urinary bladder, jejunal and medial iliac lymph nodes, pancreas, stomach, duodenum, jejunum, and colon are normal. A pathologic abdominal mass was not identified.
- The area of the penile urethra was imaged, and no abnormalities were noted.
Abdominocentesis was performed and fluid was submitted for cytology. There was evidence of chronic suppurative inflammation. Numerous intact sperm were present, with evidence of active phagocytosis of sperm components by macrophages.
Given the history of prior vasectomy, likely mechanisms for sperm contamination of the abdominal cavity may involve increased intraepididymal pressure. Causes reported in human beings include vasitis nodosa, epididymal blowout, and sperm granuloma formation. Other mechanisms cannot be ruled out. Staph saprophyticus was isolated from the fluid; this is likely a contaminant.
The patient was treated with antibiotics and he improved clinically. It is not known whether the sperm contamination of the abdomen is recent or chronic as the vasectomy was performed 3 years previously. It is also not known whether the abdominal sperm were associated with clinical disease, though an inflammatory response was present. Castration could have been performed but as the patient improved with medical management this was not elected.