Extravesical Textiloma (Gossypiboma) Mimicking a Bladder Tumor in a Dog

Case Report

A 12-year-old, 33-kg, spayed female Beauceron was referred for severe and persistent hematuria. The bitch was already spayed when she was adopted 8 years prior from a rescue center. The owner did not know if the dog had been spayed with an ovariohysterectomy or an ovariectomy. Since the dog’s adoption, she has been healthy. The dog was presented with a 3-month history of bleeding at the end of the micturition. Clinical signs resolved with a 10-day treatment of oral antibiotics (enrofloxacin 5 mg/kg q 24 hours) and an oral nonsteroidal antiinflammatory drug (tepoxalin 10 mg/kg q 24 hours), but signs recurred just after the treatment ended. The dog was presented 2 weeks after discontinuation of medications.

On presentation, the physical examination did not reveal any abnormalities except moderate pain on palpation of the caudal abdomen. Urine obtained via cystocentesis showed a urine specific gravity of 1.037; on dipstick, urine pH was 6.5, hematuria was 3+, and proteinuria was 2+. Urinalysis under light microscopy showed >100 red blood cells per high-power field and 15 to 20 white blood cells per high-power field; no casts or crystals were seen. Urine was cultured for aerobic bacteria. Results of aerobic microbial culture of the urine were negative. Because the hematuria was associated with micturition, lower urinary tract disease was suspected even though dysuria and stranguria were not reported. A serum biochemical profile was performed to evaluate renal function; results were within normal limits. A complete blood count and coagulation profile (prothrombin time, partial thromboplastin time, and platelets) were within normal limits as well.

An abdominal ultrasound was performed. The bladder showed hyper-echoic material in suspension, most likely reflecting the presence of blood in the urine. The cranioventral area of the bladder wall was markedly irregular, corrugated, and thickened [Figure 1]. The thickest area measured up to 1 cm with full distention of the bladder. The remaining areas of the bladder, including the trigone and opening of the ureters into the bladder, were not involved and appeared within normal limits. The two major rule-outs for the ultrasonographic appearance of the bladder wall were a bladder tumor or a severe cystitis. Lumbar lymph nodes did not appear enlarged. The remainder of the abdominal examination was within normal limits. Chest radiographs (three views) did not show any signs of metastasis.

As the lesion appeared cranial and focal, surgical biopsy of the mass was recommended to rule out a tumor. During incision of the linea alba, a piece of gauze was found incorporated into the abdominal wall [Figure 2]. This piece of gauze was encysted in an inflammatory granuloma, which adhered to the bladder and some small bowel. The sponge remained almost intact. Adhesions were broken with caution, and the granuloma was removed.

The external appearance of the bladder was very erythematous and edematous. The internal appearance showed severe erythema and corrugation of the bladder mucosa, but no mass was identified. Three full-thickness bladder biopsies were obtained and submitted for histopathological analysis and aerobic bacterial culture. The dog recovered well from surgery and was provided standard postoperative care. The dog received pre- and perioperative antibioprophylaxis and opioid pain medication. No antibiotics were administered after surgery, and the dog received oral meloxicam for 5 days. Two days after surgery, the gross hematuria had completely resolved.

Results of aerobic microbial culture of the bladder mucosa were negative. Aurinalysis performed at the time of suture removal did not show any abnormalities; gross and microscopic hematuria, proteinuria, and leukocyturia had resolved. An ultrasonographic examination performed 6 months after surgery revealed a normal bladder. At this time, another urinalysis was performed and found to be within normal limits. The urine has not been cultured again. One year after surgery, the owner mentioned over the phone that his dog has not displayed any urinary problem since.

Histopathological examination of the urinary bladder showed a chronic inflammatory lesion involving severe edema of the mucosa with frequent hemorrhages and hemosiderin- laden macrophages; markedly hyperplastic urothelium with multifocal ulcerations; and moderate, nonspecific perivascular infiltrates. These findings are consistent with a marked, diffuse, chronic, edematous, and hemorrhagic hyperplastic cystitis; but no signs of malignancy were noted [Figure 3]. The final diagnosis was a chronic cystitis secondary to a retained surgical sponge (gossypiboma) that created adhesions to the bladder.

Discussion

This is the first case report describing this uncommon cause of hematuria in a dog. Two similar case reports in humans have been published, in which a retained gauze in the lower abdomen formed a granuloma that infiltrated the bladder wall, creating clinical signs and imaging consistent with an invasive bladder tumor.^1,2

Textiloma is the common term for a retained surgical sponge. The technical term is gossypiboma, from the Latin word gossypium (meaning “cotton”) and the Swahili word boma (meaning “place of concealment”). The terms gauzoma or gauzeoma are sometimes used when speaking about a gauze-induced granuloma.

The human literature has numerous case reports and reviews of gossypiboma.^3,4 In veterinary medicine, only a few cases have been reported in dogs and cats.^5–13 The real incidence of retained sponges is unknown in human medicine. A study estimates an incidence of one case out of 1300 operations.¹⁴ Another study found a similar incidence and revealed an increased risk with emergency surgery, unexpected change in procedure, and high body-mass index.³ The incidence may be higher in veterinary medicine, as sponge counting and the use of radiopaque-marked sponges are less systematic.

The clinical signs associated with a gossypiboma are inconsistent, nonspecific, often subjective, and sometimes even nonexistent; such conditions make the diagnosis difficult in veterinary medicine. As in this case, most of the other reported cases in dogs involved a gauze inadvertently left during a spay procedure.^6,9 In human medicine, most (76%) of the legal claimants have no symptoms or damage except the need for a second surgery to retrieve the retained sponge.¹⁵ Pain is the most common clinical sign; other symptoms depend on the location of the retained sponge. Clinical signs can be acute or delayed after a long asymptomatic period.

In a review of eight canine cases, the median elapsed time between surgery and diagnosis was 9.5 months. In this case, clinical signs occurred >8 years after surgery. In humans, symptoms have been observed many years after surgery—sometimes >40 years later.^16–18 A retained sponge usually induces two types of reactions.¹⁹ More often, the reaction is delayed, consisting of aseptic foreign body granuloma formation and adhesions (as seen in this case). The second type of reaction occurs earlier and consists of local inflammatory reactions with or without infection, abscess, or fistulae.

The diagnosis of a retained sponge is often made preoperatively via imaging including radiography,⁹ ultrasonography, ^8,9 computerized tomography, or magnetic resonance imaging.¹² Diagnosis is easier when the gauze contains a radiopaque marker. A study of eight dogs showed that the use of radiography enabled detection of six (86%) out of seven sponges,⁹ and ultrasonography showed a hypoechoic mass that had an irregular hyperechoic center in all cases.⁹

Neoplasia and inflammatory lesions are differential diagnoses for a textiloma. In the present case, a urinary tract infection was excluded, and the ultrasonography suggested a bladder tumor that was in fact severe chronic cystitis adjacent to the gossypiboma. Two cases of gossypibomas mimicking bladder tumors were previously reported in human medicine.^1,2 Other reports have documented foreign-body granulomas mimicking neoplasms.^20,21 Gossypibomas have been suspected to induce tumors. In dogs, three extraskeletal osteosarcoma tumors associated with retained surgical gauze were described.^5,10,11 In humans, tumorigenesis of the kidney,²² the spleen,^23,24 and the colon²⁵ associated with forgotten gauze has also been reported.

Conclusion

In human medicine, retention of a surgical sponge is uncommon. This may be a more frequent occurrence in veterinary medicine, because surgical procedures are less standardized. Simple precautions are often sufficient to prevent complications. Such preventative measures include the meticulous counting of sponges; careful exploration of the body cavity before closure; and using sponges with a radiopaque marker, one by one, held by a forceps. This case of gossypiboma mimicking a tumor on ultrasound in a spayed female dog with severe hematuria and a thickened bladder wall reminds the clinician to avoid premature diagnosis of a bladder tumor without hispathological confirmation. This potential complication should also be included in the differential list when facing a tumor-like or inflammatory lesion of an organ in an animal that has undergone a previous laparotomy.