Splenic epidermoid cyst in a dog.

Splenic epithelial cysts are rare in humans and have not been reported in animals, to our knowledge. During a routine medical examination of a 12-y-old castrated male Maltese dog, a splenic mass was found and subsequently removed via splenectomy. Histologically, a well-defined multilocular cyst in the spleen was lined mostly by simple cuboidal, multifocally by stratified cuboidal, or occasionally by stratified squamous epithelium. Immunohistochemically, the lining cells were positive for cytokeratin and negative for vimentin, CD31, and Wilms tumor protein 1. The case was diagnosed as a primary splenic epidermoid cyst.

Evaluation of the validity of the double two-thirds rule for diagnosing hemangiosarcoma in dogs with nontraumatic hemoperitoneum due to a ruptured splenic mass: a systematic review.

OBJECTIVE: To evaluate the validity of the double two-thirds rule for a diagnosis of splenic hemangiosarcoma in dogs with nontraumatic hemoperitoneum due to a ruptured splenic mass. SAMPLE: Systematic literature review. PROCEDURES: 3 databases (PubMed, CAB abstracts, and World of Science) were searched in November 2020. Articles were included if data on dogs with nontraumatic hemoperitoneum due to a splenic mass were included and subsequent pathologic diagnosis could be determined. RESULTS: In total, 2,390 unique articles were identified, with 66 articles meeting the criteria for full-text review and 14 articles included for analysis. A total of 1,150 dogs were evaluated, with 73.0% (840/1,150) of dogs being diagnosed with a malignant splenic lesion and 27.0% (310/1,150) being diagnosed with a benign splenic lesion. Of the malignancies, 87.3% (733/840) were hemangiosarcoma. Levels of evidence were low, and bias was high as most included studies were retrospective case series. CLINICAL RELEVANCE: The double two-thirds rule should be refined when evaluating dogs with nontraumatic hemoperitoneum from a ruptured splenic mass, with more dogs being diagnosed with a malignancy and hemangiosarcoma specifically than the double two-thirds rule indicates. These findings may be useful in an emergency setting to guide owners on potential diagnoses for dogs with nontraumatic hemoperitoneum due to a ruptured splenic mass. However, there remains a portion of these dogs with benign conditions and nonhemangiosarcoma malignancies that may have a good long-term prognosis compared to dogs with hemangiosarcoma. Studies with higher levels of evidence, lower risks of bias, and large case numbers are needed in the literature.

Suspected spontaneous early hemorrhagic transformation of multiple ischemic strokes secondary to primary splenic torsion in a German Shepherd dog.

A 3-year-old female German Shepherd dog was presented with generalized tonic-clonic epileptic seizures, right-sided central vestibular syndrome, and right trigeminal nerve dysfunction. Acute lacunar ischemic strokes within both thalami, right side of the mesencephalon, left side of the myelencephalon, both sides of the cervical spinal cord, and acute hemorrhagic strokes within the rostral part of the right cerebellar hemisphere and right rostral colliculus were identified on magnetic resonance imaging. Additional evaluation identified multiple renal infarcts and complete splenic torsion, with entrapment of the left pancreatic lobe. Medical management, splenectomy, partial pancreatectomy, and intensive physical rehabilitation led to clinical improvement. The histology of the spleen was consistent with hemorrhagic infarction. Three months after onset, neurological examination identified only mild vestibular sequelae. The final diagnosis was multiple ischemic strokes secondary to primary splenic torsion. Spontaneous early hemorrhagic transformation, a well-known condition in human medicine, also was found in this case.

Treatment and outcomes of two pigs treated for hemoabdomen secondary to splenic disease.

OBJECTIVE: To report the management and outcomes of two pigs undergoing emergency surgery for hemoabdomen secondary to splenic disease. STUDY DESIGN: Case report. ANIMAL: Two adult pigs with hemoabdomen and suspected splenic pathology. METHODS: Pigs were admitted for several clinical signs including lethargy, inappetence, vomiting, abdominal distention, hypothermia, and tachycardia. Abdominal ultrasound and abdominocentesis led to a diagnosis of hemoabdomen secondary to splenic disease. RESULTS: The spleen was confirmed as the source of hemorrhage during midline exploratory celiotomy in both pigs. Splenic rupture resulted from splenic vein thrombosis in one pig and splenic torsion in the other. Complications included intraoperative hemorrhage and intraabdominal adhesion formation. Four years following splenectomy, one pig was euthanized because of widespread small intestinal adhesions causing luminal obstruction, while the other pig was euthanized following a diagnosis of chronic myeloid leukemia. CONCLUSIONS: A ventral midline celiotomy provided adequate exposure for splenectomy. The procedure allowed resolution of signs in both pigs. Splenic pathology, such as vessel thrombosis or torsion, may result in splenic rupture and should be considered as a differential in pigs with hemoabdomen.

Complications and outcomes associated with laparoscopic-assisted splenectomy in dogs.

OBJECTIVE: To report the perioperative characteristics and outcomes of dogs undergoing laparoscopic-assisted splenectomy (LAS). ANIMALS: 136 client-owned dogs. PROCEDURES: Multicentric retrospective study. Medical records of dogs undergoing LAS for treatment of naturally occurring splenic disease from January 1, 2014, to July 31, 2020, were reviewed. History, signalment, physical examination and preoperative diagnostic test results, procedural information, complications, duration of hospitalization, histopathologic diagnosis, and perioperative outcomes were recorded. Perioperative complications were defined using the Veterinary Cooperative Oncology Group - Common Terminology Criteria for Adverse Events (VCOG-CTCAE v2) guidelines. RESULTS: LAS was performed for treatment of a splenic mass (124/136 [91%]), immune-mediated disease (7/136 [5%]), splenomegaly (4/136 [3%]), or immune-mediated disease in conjunction with a splenic mass (1/136 [1%]). Median splenic mass size was 1.3 cm3/kg body weight. Conversion to open laparotomy occurred in 5.9% (8/136) of dogs. Complications occurred in 78 dogs, with all being grade 2 or lower. Median surgical time was 47 minutes, and median postoperative hospital stay was 28 hours. All but 1 dog survived to discharge, the exception being postoperative death due to a suspected portal vein thrombus. CLINICAL RELEVANCE: In the dogs of this report, LAS was associated with low rates of major complications, morbidity, and mortality when performed for a variety of splenic pathologies. Minimally invasive surgeons can consider the LAS technique to perform total splenectomy in dogs without hemoabdomen and with spleens with modest-sized splenic masses up to 55.2 cm3/kg, with minimal rates of complications, morbidity, and mortality.

Retroperitoneal abscess and splenitis with Clostridium spp. in a dog.

An 11-year-old spayed female Basset Hound was presented to the Colorado State University Veterinary Teaching Hospital for evaluation of a 7-week history of intermittent collapse, waxing and waning lethargy, and hyporexia. Abdominal ultrasound revealed a 6-mm hypoechoic splenic nodule that, on cytologic evaluation, revealed marked neutrophilic inflammation with intracellular and extracellular bacterial rods frequently producing oval subterminal to terminal endospores, suggestive of Clostridium. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) performed on bacteria isolated from this nodule initially identified a Clostridium species, which was eventually confirmed with 16 s rDNA sequencing. Computed tomography (CT) and exploratory laparotomy subsequently identified a 2.5-cm diameter tubular structure beginning at the caudal aspect of the right kidney and coursing caudally containing gas and fluid, consistent with a retroperitoneal abscess, which was resected and also cultured Clostridium spp. The dog was discharged 3 days postoperatively and was alive at the time of writing, 7 months after discharge. This case highlights a previously unrecognized bacterial agent in a retroperitoneal abscess. The use of cytologic evaluation yielded a diagnosis of endospore-forming bacteria suggestive of Clostridium sooner than culture and histopathology, which allowed for adjustment in the antibiotic protocol.

Accuracy of B-mode ultrasound and ARFI elastography in predicting malignancy of canine splenic lesions.

The objective was to evaluate the accuracy of B-mode ultrasonography and ARFI elastography in detecting malignancy in canine splenic lesions. Thirty-seven spleens with abnormalities (16 benign and 21 malignant) from dogs of different breeds and ages were evaluated. Echogenicity, echotexture, organ length and height were evaluated using B-mode. By ARFI elastography, tissue stiffness was evaluated qualitatively (elastogram) and quantitatively (measuring the shear wave velocity-SWV). Lesions were classified as diffuse, focal or multifocal (cranial, medial or caudal portion) and comparisons of the SWV between the injured and non-injured areas were performed. In the B-mode, no features were associated to malignancy (P > 0.05). In the elastogram, 35 spleens were non-deformable and 2 deformable, having no association with malignancy. The greater SWV was observed in malignant lesions (3.4 ± 0.6 m/s), followed by areas free from alterations (2.1 ± 0.3 m/s) and benign lesions (1.7 ± 0.5 m/s), with difference between groups (P < 0.0001). It was found that a SWV > 2.6 m/s indicates malignancy of canine splenic lesions (sensitivity of 95%, specificity of 100%, PPV of 100%, NPV of 94% and accuracy of 97%), concluding that ARFI elastography is a promising technique for differentiating malignancy in these lesions.

Chronic splenic torsion in a dog with an accessory spleen.

A 4-year-old, neutered male, mixed breed Old English sheepdog was presented for evaluation and treatment of anorexia, vomiting, and diarrhea. Presumptive severe pancreatitis was diagnosed based on the referral bloodwork. Abdominal ultrasonography identified a suspected liver lobe torsion based on the presence of a normal spleen. However, an exploratory laparotomy identified a splenic torsion in addition to a grossly normal spleen. Key clinical message: This case demonstrates that a second, potentially large area of splenic tissue (ectopic or accessory) can be present in the dog; therefore, the presence of a normal appearing spleen on abdominal ultrasonography does not rule out splenic torsion.

Torsion splénique chronique chez un chien avec une rate accessoire. Un chien berger anglais de race mixte âgé de 4 ans, mâle castré, a été présenté pour évaluation et traitement d'anorexie, de vomissements et de diarrhée. Une pancréatite sévère présumée a été diagnostiquée sur la base des analyses sanguines. L'échographie abdominale a identifié une torsion suspectée du lobe hépatique basée sur la présence d'une rate normale. Cependant, une laparotomie exploratrice a identifié une torsion splénique en plus d'une rate grossièrement normale.Message clinique clé :Ce cas démontre qu'une deuxième zone potentiellement large de tissu splénique (ectopique ou accessoire) peut être présente chez le chien; par conséquent, la présence d'une rate d'apparence normale à l'échographie abdominale n'exclut pas une torsion de la rate.(Traduit par Dr Serge Messier).

Ultrasonographic and CT diagnosis of a complete splenic duplication with right splenic torsion and presumed regional splenic vein hypertension in a dog.

An 8-year-old mixed breed dog, was referred for lethargy, abdominal discomfort, hematemesis, and melena. Abdominal ultrasound revealed mineralization of the "right splenic vein" with collateral spiraling and a suspected splenic duplication. Computed tomography confirmed the duplication along with torsion of the splenic pedicle. Exploratory laparotomy confirmed the splenic torsion associated with congestion of the gastrointestinal vessels, indicative of a chronic onset of secondary regional splenic vein hypertension.

Serological evidence of avian HEV antibodies in apparently healthy chickens in southwest Nigeria.

Avian hepatitis E virus (aHEV) is associated with hepatitis-splenomegaly syndrome, big liver and spleen disease and hepatic rupture haemorrhage syndrome. However, the knowledge about aHEV in commercial layer chickens in Nigeria is scarce. In this study, 460 serum samples obtained from 36 apparently healthy commercial layer chicken flocks in three states (Ogun, Osun and Oyo States) of southwestern Nigeria were analysed by enzyme linked immunosorbent assay for the presence of anti-aHEV immunoglobulin Y (IgY) antibodies. In total, the overall seroprevalence of anti-aHEV antibodies was 14.6%. The serological analysis revealed that 75% of the flocks examined were positive for anti-aHEV IgY antibodies from chickens of various ages in all three states. The percentage of the seropositive chickens in the three states varied from flock to flock ranging from 60% to 88.8% and seropositive chickens were detected at any age (24-52 weeks of age) without significant differences between the age groups. This is the first report assessing the presence of aHEV antibodies in chickens from Nigeria. The detection of anti-aHEV antibodies in commercial layer chickens in this study emphasizes the importance of serosurveillance in disease monitoring due to the economic threat posed by aHEV as a result of decreased egg production and increased mortality in affected commercial layer chicken farms. However, further studies are essential to reveal the clinical implications and to assess the real burden of aHEV in Nigeria.

Spontaneous emphysematous splenitis: Radiographic and ultrasonographic findings in three Golden Retriever dogs.

Spontaneous emphysematous splenitis is a life-threatening condition reported rarely in humans; however, published reports in dogs are currently lacking. The aim of this multicentric, retrospective, case series design study was to describe radiographic and ultrasonographic imaging findings in Golden Retriever dogs diagnosed with spontaneous emphysematous splenitis. A total of three dogs were sampled. All dogs had a history of lethargy, diarrhea, and weight loss. Radiographic findings in all dogs included a mass effect with focal or multifocal coalescing "vesicular-like" gas pattern in the splenic region and focal loss of serosal detail. Ultrasonographic findings in all dogs included focal or multifocal irregularly shaped, hypoechoic areas containing a mixture of hyperechoic fluid and gas within the splenic parenchyma, hyperechoic abdominal free fluid, and generalized hyperechoic mesenteric fat without evidence of splenic torsion. Pneumoperitoneum was detected ultrasonographically and radiographically in two dogs. All three dogs underwent splenectomy and splenic torsion was definitively ruled out at surgery. One dog died three days after surgery, whereas the other two dogs recovered uneventfully. Culture of the splenic tissue and free abdominal fluid was positive for Clostridium spp. in all three cases. Findings supported inclusion of spontaneous emphysematous splenitis and septic peritonitis as differential diagnoses for dogs with this combination of clinical and imaging characteristics.

Disseminated Neospora caninum infection in a dog with severe colitis.

A 12-y-old spayed female Schipperke dog with a previous diagnosis of inflammatory bowel disease was presented with a 2-mo history of severe colitis. The patient's condition progressed to hepatopathy, pneumonia, and dermatitis following management with prednisolone and dexamethasone sodium phosphate. Colonic biopsies identified severe necrosuppurative colitis with free and intracellular parasitic zoites. Postmortem examination confirmed extensive chronic-active ulcerative colitis, severe acute necrotizing hepatitis and splenitis, interstitial pneumonia, ulcerative dermatitis, myelitis (bone marrow), and mild meningoencephalitis with variable numbers of intracellular and extracellular protozoal zoites. PCR on samples of fresh colon was positive for Neospora caninum. Immunohistochemistry identified N. caninum tachyzoites in sections of colon, and a single tissue cyst in sections of brain. Administration of immunosuppressive drugs may have allowed systemic dissemination of Neospora from the intestinal tract.

Simultaneous Torsion of a Uterine Horn and Spleen in a Pregnant Two-Year-Old Crossbreed Bitch: A Case Report.

A pregnant 2-year-old mixed-breed dog was admitted with a 2-day history of lethargy, anorexia and painful abdominal distension. Clinical manifestations were unspecific and mainly suggested hypovolemic shock. Physical examination, ultrasonographic evaluation and radiographs confirmed mid-late pregnancy and evident signs of fetal death and peritoneal effusion. An exploratory laparotomy was immediately initiated which revealed torsion of the right gravid uterine horn over the left one and, simultaneously, the unexpected presence of splenic torsion and rupture, with a stretched omentum covering and exerting tension on the spleen's cranial pole. Histopathology revealed hemorrhagic infarction of the uterus and spleen. The animal recovered uneventfully and was later submitted to a preventive gastropexy.

Splenic extramedullary hematopoiesis in dogs is frequently detected on multiphase multidetector-row CT as hypervascular nodules.

Extramedullary hematopoiesis (EMH) is the formation and development of blood cells outside the bone marrow, and in dogs it frequently occurs in the spleen. Although splenic EMH is a relatively common condition, data regarding its appearance in veterinary medicine are lacking. Our aim was to describe different multidetector computed tomographic (MDCT) features of splenic EMH in dogs. In this descriptive retrospective study, dogs with cytological diagnosis of splenic EMH and three-phase MDCT study of the abdomen were included. Multi-detector CT findings recorded were splenomegaly, appearance of the parenchyma, and mean attenuation of the spleen and lesions. Out of 89 dogs included, 55 (62%) presented multifocal nodular aspect, 14 (16%) mass, 12 (13%) diffuse heterogeneous parenchyma, and eight (9%) normal spleen. Most lesions were hyperattenuating to the parenchyma in the arterial (57/89, 64%) and portal (59/89, 66%) phases; whereas in the interstitial phase only 40 of 89 (45%) were hyperattenuating. The mean attenuations of the lesions were higher compared to the values of the adjacent spleen, and the difference of the mean attenuation between the hyperattenuating lesions and the parenchyma was significantly higher in arterial and portal phases than in interstitial phase (P < .0001). The most frequent MDCT aspect of splenic extramedullary hematopoiesis consists of multiple nodules hyperattenuating to the normal spleen, best visualized in the arterial and portal phases.

A novel herpesvirus in a white stork associated with splenic and hepatic necrosis.

We identified a novel herpesvirus in a captive juvenile white stork (Ciconia ciconia) that experienced progressive weight loss followed by death. Histologic findings included severe splenic and hepatic necrosis, and intranuclear inclusion bodies in hepatocytes and unidentified splenic cells. The virus was amplified, sequenced, and subsequently accessioned as Ciconiid alphaherpesvirus 1. Phylogenetic analysis was performed and revealed that this virus is more closely related to mammalian herpesviruses than those within the genus Mardivirus. Additional sequence of viruses in this area may elucidate the ancestral virus that jumped from reptilian to mammalian hosts.

Large-volume pneumoperitoneum and septic peritonitis secondary to splenic abscess rupture in a dog.

An 11-year-old spayed female American pit bull terrier mixed breed dog was presented because of hyporexia and abdominal distension. The dog had large-volume free peritoneal gas on imaging and septic neutrophilic exudate on abdominocentesis. Exploratory laparotomy revealed a ruptured splenic mass draining purulent material. A splenectomy was performed and the abdomen was lavaged. Culture samples grew an anaerobic Gram-positive rod. The dog was discharged 4 days after surgery with no residual problems noted 1 week later. To our knowledge, this is the first report of large-volume pneumoperitoneum and septic peritonitis secondary to rupture of a splenic abscess.

Pneumopéritoine de grand volume et péritonite septique secondaire à la rupture d'un abcès splénique chez un chien. Une chienne stérilisée de race pitbull terrier américain croisée âgée de 11 ans fut présentée à cause d'hyporexie et de distension abdominale. Lors de l'examen par imagerie on nota un large volume de gaz péritonéal libre et un exsudat neutrophilique septique lors de l'abdominocenthèse. Une laparotomie exploratoire révéla une masse splénique rupturée qui drainait du matériel purulent. Une splénectomie fut réalisée, et l'abdomen fut soumis à un lavage. La culture d'échantillons permis la croissance d'un bâtonnet à Gram-positif anaérobie. Le chien reçu son congé 4 jours après la chirurgie et aucun problème résiduel ne fut noté 1 semaine plus tard. À notre connaissance il s'agit du premier rapport d'un pneumopéritoine de grand volume et de péritonite septique secondaire à la rupture d'un abcès splénique chez un chien.(Traduit par Dr Serge Messier).

CT characteristics of primary splenic torsion in eight dogs.

Splenic torsion is a rare potentially life-threatening condition characterized by rotation of the spleen around the gastrosplenic and phrenosplenic ligaments leading to occlusion of venous drainage and arterial supply. This retrospective study describes the CT characteristics for dogs with surgically confirmed splenic torsion from 2013 to 2018 using the submissions to a large multinational teleradiology database. Eight dogs had the splenic torsion confirmed with surgery. Seven of eight cases had histology confirming congestion, hemorrhage, and necrosis, and one had concurrent myelolipoma infiltration. The CT characteristics included an enlarged (8/8), rounded (7/8), folded C-shaped spleen (8/8) with a difference of median parenchymal attenuation between pre- and postcontrast of +1.15 HU (Hounsfield units). Other common features included a mainly homogeneous parenchyma on pre- and post-contrast images (6/8), lack of subjective and objective vascular and parenchymal contrast enhancement (6/8) and free peritoneal fluid (6/8). A "whirl sign" was seen in the majority of cases (7/8) alongside a strongly hyperattenuating center (95-416 HU) on the precontrast images (5/7), which has not been previously described in the veterinary literature. Gastric position was normal in all cases. More variable CT characteristics of the confirmed torsions were attributable to suspected partial torsion and myelolipomatous infiltration. Overall, primary splenic torsion confirmed with surgery showed consistent characteristics on CT.

Ultrasonographic honeycomb pattern of the spleen in cats: correlation with pathological diagnosis in 33 cases.

OBJECTIVES: The aim of this study was to evaluate the relationship between the ultrasonographic (US) diffuse honeycomb pattern (HCP) of the spleen and a pathological diagnosis in cats, and to assess the influence of transducer type on HCP visualisation. METHODS: Abdominal ultrasounds of cats with an HCP were reviewed and splenic size, shape, margination, other parenchymal alterations and splenic hilar lymphadenopathy were recorded. When applicable, images acquired with high-frequency linear and curvilinear transducers were compared to determine if an HCP was more frequently demonstrated on high-resolution images. A retrospective review of the corresponding splenic cytohistopathological samples was also performed. RESULTS: Thirty-three cats met the inclusion criteria. Five cases were diagnosed by histology and 28 by cytology, confirmed by PCR for antigen receptor rearrangements (PARR) in uncertain cases. There were 15 cases of lymphoid hyperplasia, eight cases of lymphoma (four B cell, three T cell and one large granular lymphocytes), six cats with splenitis, three with extramedullary haematopoiesis and one with histiocytic sarcoma. The prevalence of lymphoma in cats with an HCP of the spleen was 24%. Splenomegaly was the most frequent US feature associated with an HCP and was observed in all lymphoma cases. In the images obtained from both high-frequency linear and micro-convex transducers the visualisation of an HCP was enabled in all cases (24/24) and in 62.5% (15/24), respectively. CONCLUSIONS AND RELEVANCE: Based on our findings, a US HCP of the spleen in cats can be associated with benign and malignant disorders and is infrequently associated with lymphoma in comparison with dogs. Cytological or histological examination, possibly supplemented by PARR, should always be performed for diagnostic support. Use of high-frequency linear transducers is recommended to properly recognise an HCP or subtle changes in splenic parenchyma.

Clinical relevance of splenic nodules or heterogeneous splenic parenchyma assessed by cytologic evaluation of fine-needle samples in 125 dogs (2011-2015).

BACKGROUND: Splenic nodules and heterogeneous parenchyma are seen frequently in abdominal ultrasound examinations of dogs, but the clinical importance of these lesions remains unclear. OBJECTIVES: To determine whether specific ultrasonographic findings correlate with clinically relevant cytologic diagnoses and determine what sonographic features are correlated with these diagnoses. Another objective was to develop a scoring rubric to help clinicians make decisions on whether or not certain ultasonographic findings of the spleen warrant evaluation by fine-needle cytology. ANIMALS: One-hundred twenty-five adult client-owned dogs with ultrasonographically identified splenic nodules, heterogeneous parenchyma, or both. METHODS: Medical records were retrospectively searched for ultrasound-guided splenic fine-needle cytology reports. Ultrasonographic images were assessed for nodule number, size, echogenicity and distal enhancement, degree of splenic heterogeneity, and peritoneal fluid. Dogs were divided into 2 groups: those with clinically important or clinically irrelevant cytologic findings. Potentially useful and discriminatory ultrasonographic findings were identified by statistical analysis, and the most useful findings were used to generate the scoring rubric. RESULTS: The clinically important group included 25 of 125 dogs (22 malignancies, 3 suppurative inflammation). Splenic nodules 1-2 cm in diameter, peritoneal fluid, and >1 targetoid nodule were associated with clinically important cytologic findings. Receiver operator characteristic analysis showed that the scoring rubric was useful for identifying dogs in the clinically important group. CONCLUSIONS AND CLINICAL IMPORTANCE: Splenic fine-needle cytologic findings identified a clinically relevant diagnosis in 20% of dogs, and larger nodule size, number of targetoid lesions, and presence of peritoneal fluid increase the likelihood of detection of clinically important disease.