Splenosis in a dog

A 6-year-old male Rhodesian Ridgeback dog developed splenosis following splenectomy for a rupture of the spleen. The dog did well for 4 years following splenectomy but then developed progressive hepatomegaly, leading to the death of the animal. Grossly the abdomen was filled with masses of tissue arising from the liver. Multiple nodules of various sizes were seen in the remainder of the liver and attached to the mesentery, diaphragm and peritoneal wall. Histologically, the lesions contained splenic tissue consisting of both red and white pulp, and were characterized by all the normal cell elements of the spleen, including erythropoietic tissue. The proportion of red to white pulp was, however, abnormal, and the fibromuscular septae and sheath arteries were not obvious. In the smaller lesions, and in the margins of the large lesions, splenic tissue replaced the hepatic tissue except for the bile ducts. The multiple, intrahepatic nodules indicated splenic vein embolism.     

流行性白血病病牛的免疫病理学观察

用８种单克隆抗体（ＴＨ１４Ｂ、ＢＡＱ４４Ａ、ＢＩｇ４５Ａ、ＢＩｇ７１５Ａ、ＢＩｇ５０１Ｅ、ＣＡＣＴ１０５Ａ、ＭＭ１Ａ、ＡＨ－ＣＣ１２５）结合常规病理学方法,对１０头流行性白血病病牛的免疫病理学进行了观察。结果：患病较轻时,淋巴结内的淋巴小结肿大,生发中心明显,副皮质区显著增宽。脾脏中的脾小体亦增大,动脉周围淋巴鞘增厚。用ＭｃＡｂ证明,在淋巴结和脾脏有较多的Ｂ淋巴细胞和大量Ｔ淋巴细胞。患病较重时,淋     

Hypoglycemia associated with disseminated metastatic tonsillar squamous cell carcinoma producing insulin‐like growth factor‐I in a Pomeranian dog

A 13‐year‐old spayed female Pomeranian dog was presented for persistent, severe hypoglycemia (37 mg/dL; reference interval [RI] 75‐128 mg/dL). Progressive nonregenerative anemia (hematocrit 23.3%‐15.9%; RI 37.0%‐55.0%) and severe thrombocytopenia (36 000/µL; RI 200‐500 000/µL) were also noted. The serum insulin concentration was low (0.24 ng/mL; RI 0.302‐1.277 ng/mL). Computed tomography revealed multiple splenic nodules (1‐6 mm in diameter) and several hepatic nodules (7.6, 12 mm in diameter). Ultrasound‐guided fine‐needle aspiration of the splenic and hepatic nodules revealed low numbers of epithelial cells with mild cellular atypia, suggestive of a metastatic epithelial tumor, but the primary site was unknown at that time. On careful oral examination under general anesthesia, an enlarged right tonsil was noted grossly, and histopathologic examination of the tonsil diagnosed squamous cell carcinoma. Bone marrow aspirates and biopsies of the splenic and hepatic nodules were performed; all samples were diagnosed as metastatic carcinoma on histopathologic examination. No nodules were present in the pancreas, despite careful palpation during exploratory laparotomy. On immunohistochemistry, the neoplastic cells were positive for cytokeratin AE1/3 and insulin‐like growth factor (IGF)‐I but were negative for chromogranin A, PGP9.5, insulin, and inconclusive for IGF‐II. This is the first report of a primary IGF‐I‐producing squamous cell carcinoma in the tonsil of a dog with metastases to bone marrow, liver, and spleen, resulting in hypoglycemia.     

ULTRASONOGRAPHIC APPEARANCE OF HISTOPLASMOSIS IDENTIFIED IN THE SPLEEN IN 15 CATS

Histoplasmosis is the second most common fungal infection reported in the cat. The disseminated form involving lung, liver, lymph nodes, spleen, and bone marrow is a frequent manifestation of the disease. Limited information is available in the literature regarding the ultrasonographic appearance of the spleen in cats with disseminated or splenic histoplasmosis. A retrospective review of splenic ultrasound images from 15 cats confirmed to have histoplasmosis by splenic aspirates was performed. Size, echotexture, echogenicity, margin appearance, presence of nodules, and the overall shape of the spleen were reported in each case. Splenomegaly was documented in all cases (15/15) and a hypoechoic appearance of the spleen was documented in 14/15 of cases. The spleen was diffusely and uniformly affected in 14/15 (six homogenous and eight with a subtle mottled appearance) and had discrete nodules in 1/15 cats. Histoplasmosis should be included in the differential list for an enlarged and hypoechoic spleen in cats with consistent clinical findings. Additionally, ultrasound guided splenic aspirate may be a useful method to obtain a cytology sample for diagnosis.     

Ultrasonographic features of splenic lymphosarcoma in dogs: 12 cases (1980-1986)

The ultrasonographic appearance of the spleen and adjacent organs in 12 dogs with splenic lymphosarcoma was reviewed. Poorly marginated hypoechoic to anechoic nodules (4 mm to 3 cm in diameter) were found in all dogs. The anechoic nodules did not result in reflective shadowing or acoustic enhancement of the underlying tissues. The remainder of the splenic parenchyma appeared relatively hypoechoic when compared with the liver or renal cortices in 9 dogs. Recognition of this ultrasonographic pattern appears to be a useful diagnostic tool. Needle aspiration guided ultrasonographically will then enable histologic confirmation of lymphosarcoma.     

脑炎原虫病兔免疫器官的病理形态学观察

研究脑炎原虫病兔外周免疫器官的形态学变化,采集20只病兔和12只对照兔的淋巴结、脾脏和圆小囊,通过临床检查,病理剖检,病理切片的HE染色、吉姆萨染色和免疫组织化学染色进行了比较观察。结果表明病兔淋巴结内的淋巴小结数量增多,生发中心明显,髓索增粗,副皮质区增宽。脾脏的脾小结增多,变大,具有明显的生发中心,边缘区明显增宽,动脉周围淋巴鞘明显变大,聚集大量淋巴细胞。圆小囊的淋巴小结增大,数量增多,生发中心明显,淋巴小结周围弥散大量淋巴细胞。通过α-ANAE和sABC染色,在淋巴结、脾脏和圆小囊中均可检出大量T细胞、巨噬细胞和IgG阳性细胞。据此认为患脑炎原虫病时,病兔的体液免疫和细胞免疫均增强,但以细胞免疫反应更强。     

Prevalence and type of splenic diseases in cats: 455 cases (1985-1991).

Retrospective data on the type and prevalence of splenic disease in cats were evaluated in a large number of feline splenic tissues (n = 455) submitted as surgical and necropsy specimens from private veterinary hospitals in California during a period of approximately 5.5 years. Primary and metastatic neoplasia accounted for 37% of all feline splenic lesions. Mastocytoma, lymphosarcoma, myeloproliferative disease, and hemangiosarcoma, in that order, accounted for the bulk of neoplasia. Submission of accessory splenic tissue from either the omentum or pancreas accounted for 4% (17/455), whereas hyperplastic nodules, hematomas, and the combination of these changes in the spleen accounted for 4% (19/455). Splenitis was found in 2% (8/455) of submissions. Thromboembolism with regional splenic infarction accounted for 1% (4/455) of splenic lesions in cats. The remaining splenic lesions each accounted for less than 1% of total splenic submissions, and as such, were considered incidental and of questionable clinical importance.     

Prevalence, type, and importance of splenic diseases in dogs: 1,480 cases (1985-1989).

The prevalence data of splenic diseases from 3 sources were studied. Group 1 consisted of a general diagnostic survey of accessions submitted from private veterinary hospitals in California during a period of approximately 4 years and included 1,372 submissions of canine splenic tissue. Group 2 consisted of surgical splenectomy specimens from 92 dogs; the specimens were submitted to the laboratory for gross and histologic evaluation prior to fixation, and a questionnaire was subsequently sent to determine the outcome of the disease. Group 3 was made up of specimens of 105 splenic lesions derived from a large colony of Beagles with complete medical records and records of pathologic findings. In this study, splenic hematoma and hyperplastic nodule, not hemangiosarcoma, made up the bulk of splenic lesions. Hemangiosarcoma was the most frequent neoplasm of the canine spleen, but the combined prevalence of all other splenic neoplasms was similar to that of hemangiosarcoma alone. Splenic hematoma and hemangiosarcoma were grossly indistinguishable in most cases. Hyperplastic lymphoid nodules and hematomas of the spleen appeared to represent a continuum. If that finding was correlated with microscopic splenic blood flow, specific causal relationship could be suggested. Prognostically, the live/dead ratio and mean survival of dogs with various splenic lesions differed significantly.     

Microfilarial granulomas in the spleens of wild-caught cynomolgus monkeys (Macaca fascicularis)

Splenic nodules from 38 cynomolgus monkeys (Macaca fascicularis) which were captured in Malaysia and Indonesia were studied histologically. The lesions were characterized by well-circumscribed focal fibrosis, accumulation of eosinophils and histiocytes, hemorrhage or hemosiderosis, and loss of normal splenic architecture. Small arteries in the lesion frequently had intimal thickening and narrowing of the lumen in addition to the presence of microfilariae. Microfilariae were also seen in the extravascular area of the lesion, and were occasionally engulfed by multinucleated giant cells. The splenic lesion was thought to have been initiated by incomplete infarction caused by intimal thickening and microfilarial occupation of the small arteries.     

Circulating melanin-containing cells and neutrophils with phagocytized melanin granules in a horse with disseminated melanoma

An 18-year-old, grey, Thoroughbred Cross gelding was referred to the Cummings School of Veterinary Medicine at Tufts University following a 3-week history of low-grade fever of unknown origin, distal limb swelling, and weight loss. Clinical examination identified a few black, round, smooth nodules along the ventral aspect of the proximal tail. Transabdominal ultrasound showed a markedly enlarged heterogenous spleen, hyperechoic liver nodules, and evidence of peritonitis with fibrin deposition. A mature neutrophilia was noted on complete blood count with variable numbers of phagocytized granules within neutrophils. The granules did not stain with Perl's Prussian blue, and were intensely positive when stained with Fontana-Mason, consistent with melanin. On necropsy, the spleen occupied approximately one-third of the abdominal cavity and was diffusely firm with abundant black pigment on cut section. The medullary space of the 18th thoracic vertebra was also diffusely blackened. The splenic, mediastinal, and tracheobronchial lymph nodes were five times the normal size and diffusely pigmented. The final anatomic diagnosis was disseminated malignant melanoma with extensive splenic involvement and hemolymphatic and vascular neoplastic dissemination. To the authors' knowledge, this is the first full report to identify circulating neutrophils containing phagocytized melanin granules, which confirmed an antemortem diagnosis of disseminated melanoma.     

Conjunctival dacryops in a domestic shorthair cat

A 1-year-old spayed female domestic shorthair cat with a 1-week history of a conjunctival mass located in the dorsolateral quadrant of the right eye was presented to a referral hospital. Ophthalmic examination revealed a pink, fluctuant, and non-painful cystic swelling of the upper right palpebral conjunctiva. An ocular ultrasound confirmed the presence of a fluid-filled cystic structure that extended into the temporal orbit. The histopathology of the excisional biopsy revealed multiple cysts lined by ductal epithelium along with dilated lacrimal gland ducts and lymphocytic nodules adjacent to the dorsal lacrimal gland; consistent with a diagnosis of dacryops.     

ULTRASONOGRAPHIC FEATURES OF CANINE ABDOMINAL MALIGNANT HISTIOCYTOSIS

Ultrasonographic features of canine abdominal malignant histiocytosis (MH) of 16 dogs are reported. The most common finding was the presence of hypoechoic nodules in the spleen, some of which caused distortion of the splenic margin. The liver was the second-most commonly affected organ. Hepatic ultrasonographic features were highly variable, including hypoechoic, hyperechoic, or mixed echogenic lesions. Other common ultrasonographic abnormalities included hypoechoic nodules in the kidneys and mesenteric and medial iliac lymphadenopathy. The results of this study suggest that the ultrasonographic appearance of canine abdominal MH is nonspecific, and definitive diagnosis requires cytologic or histologic examination.     

Uterine myxoid leiomyosarcoma with widespread metastases in a cat

A 10-year-old domestic shorthair cat was spayed to remove bilateral ovarian masses and an enlarged uterus. Both ovaries were effaced by large, irregular, firm, glistening, white cystic masses filled with clear viscous fluid. The uterine lumen was filled with copious amounts of clear viscous fluid, and the uterus contained multiple, firm, glistening, white nodules. Histologic examination revealed an invasive spindle cell neoplasm with features of malignancy, and extensive hypocellular areas containing an alcian blue-positive myxoid matrix. Tumor cells expressed caldesmon, alpha-smooth muscle actin, and estrogen receptor but were negative for desmin. The animal was euthanized 1 month later because of suspected local tumor recurrence. At necropsy, the abdominal cavity contained 120 ml of mucoid ascites; multiple tumor nodules were present in the abdominal and thoracic cavities. The clinical behavior and gross, microscopic, and immunohistochemical findings established a diagnosis of myxoid leiomyosarcoma.     

Use of chemical ablation with trichloroacetic acid to treat eyelid apocrine hidrocystomas in a cat

CASE DESCRIPTION: A 7-year-old Persian cat was evaluated for recurrence of multiple cystic periocular masses. A number of cyst-like lesions had been resected from the left eyelids 18 months earlier, with lesions recurring within 6 months after surgery. The cat had blepharospasm and signs of discomfort following rupture of the largest cyst the day prior to examination. Previous histologic examination of the cysts had revealed apocrine hidrocystomas. CLINICAL FINDINGS: Multiple pigmented nodules were seen around the skin of the upper and lower left eyelids. The nodules were brownish to black, round, soft, and fluid-filled. Signs of pain were not evident during palpation of the nodules. TREATMENT AND OUTCOME: The largest cyst on the upper eyelid was removed by means of a V-shaped full-thickness excision. Histologic and immunohistochemical examination of the excised tissue confirmed the diagnosis of apocrine hidrocystoma. The remaining periocular cysts were surgically debrided and then treated topically with 20% trichloroacetic acid. All lesions healed rapidly without any signs of discomfort. During a recheck examination 12 months later, the upper and lower left eyelids appeared morphologically normal, and there was no evidence of recurrence. CLINICAL RELEVANCE: Findings suggested that chemical ablation with trichloroacetic acid may be a useful treatment for apocrine hidrocystomas in cats.     

周岁黑熊脾脏的组织学和组织化学研究

采用石蜡和冰冻切片方法，进行３Ｍ·Ｅ和Ｗｉｌｄｅｒ染色，并以酸性α－醋酸萘醋酶（ＡＮＡＥ）法显示Ｔ淋巴细胞的分布。结果表明：周岁黑熊（Ｓｅｌｅｎａｒｃｔｏｓｔｈｉｂｅｔａｎｕｓ）脾脏小梁较多，脾窦发育不良．动脉周围淋巴鞘发达；鞘动脉位于脾索内，靠近边缘区；椭球厚为３０－４０μｍ。ＡＮＡＥ阳性反应的淋巴细胞主要分布于白髓的中央动脉周围淋巴鞘内，其次是脾小结外周，边缘区和椭球内。     

Multiple eyelid apocrine hidrocystomas in two Persian cats

Abstract Two middle-aged Persian cats were presented for evaluation of periocular masses. On examination, multiple pigmented nodules, 2-10 mm in diameter, were found in the periocular skin. Excisional biopsy revealed unilocular cystic lesions derived from apocrine sweat glands and resembling apocrine hidrocystomas of the eyelids described in humans. Immunostaining for Ki67 identified actively proliferating epithelial cells and demonstrated, for the first time, that these cystic lesions are adenomatous proliferative tumors (cystadenomas) rather than retention cysts. In both cases, additional lesions appeared within 6 to 9 months at affected and previously unaffected sites on the eyelids.     

IMPROVED DETECTION OF METASTATIC HEPATIC HEMANGIOSARCOMA NODULES WITH CONTRAST ULTRASOUND IN THREE DOGS

Three dogs with a splenic hemangiosarcoma were imaged with conventional gray-scale ultrasound and no lesions were identified in the liver. After administration of intravenous ultrasound contrast medium (Definity) small, poorly enhanced, hypoechoic nodules were identified in the liver in each dog. The spleen and liver lesions were identified at surgery and the dogs underwent splenectomy and nodule biopsy. All lesions were identified histologically as hemangiosarcoma. These preliminary results suggest that contrast ultrasound may result in improved detectability of metastatic hepatic hemangiosarcoma.     

Renal collecting duct carcinoma in a dog

An 8-year-old, male, mongrel dog developed severe cough and anorexia and died within 3 months. Autopsy revealed an invasive grayish-white mass in the right kidney and multiple nodules in the lungs, thoracic wall, and spleen. Histologically, the renal mass and the other nodules were mainly composed of papillotubular structures lined by oval-to-polygonal pleomorphic cells. The cells were reactive with DBA, PNA, and UEA-1 lectins and positive for vimentin but negative for CD10 and high molecular weight cytokeratin. Because of its histological, histochemical, and immunohistochemical similarities with human collecting duct carcinoma (CDC), a diagnosis of renal collecting duct carcinoma with pulmonary, thoracic, and splenic metastases was established. To our knowledge, this is the first case report of CDC in animals.     

CELLULAR FEATURES OF SONOGRAPHIC TARGET LESIONS OF THE LIVER AND SPLEEN IN 21 DOGS AND A CAT

Target lesions are seen in ultrasound images of the liver or spleen as nodules or masses with a hypoechoic rim and a hyperechoic or isoechoic center. To assess the diagnostic significance of finding a target lesion, the cytologic and/or histopathologic findings were reviewed in a series of 21 dogs and a cat that had hepatic and/or splenic target lesions noted during abdominal ultrasonography. Twelve of 16 hepatic target lesions and 5 of 7 splenic target lesions were malignant. In this series, the finding of one or more target lesions in the liver or spleen had a positive predictive value for malignancy of 74%; for the finding of multiple target lesions in one organ, the positive predictive value for malignancy was 81%. Benign lesions associated with target lesions were nodular hyperplasia of the liver and spleen, pyogranulomatous hepatitis, cirrhosis, and chronic active hepatitis.     

ULTRASONOGRAPHIC IDENTIFICATION AND CHARACTERIZATION OF SPLENIC NODULAR LIPOMATOSIS OR MYELOLIPOMAS IN CHEETAHS (ACINONYX JUBATUS)

A total of 44 live cheetahs were examined sonographically between 1989 and 1994. Seventeen of these animals originated from 4 European facilities, the other 27 cheetahs were examined in 3 facilities in Namibia. Evaluation of the cheetahs included a clinical examination, abdominal ultrasound, and complete blood work. Splenic myelolipomas were diagnosed sonographically in 11 cheetahs. In 7 cheetahs the diagnosis was confirmed at necropsy. Nine of the 14 cheetahs in Europe had myelolipomas in the spleen, while in the African cheetahs there were only 2 animals with myelolipomas. Histologically these lesions were characterized by fatty nodules. A more fitting term of Nodular Lipomatosis of the spleen is therefore suggested. All cheetahs with nodular lipomatosis of the spleen, had concurrent chronic diseases at necropsy. An indicator function of splenic nodular lipomatosis for chronic disease and/or stress is possible.