Multisystemic, eosinophilic, epitheliotropic disease with intestinal lymphosarcoma in a horse

Multisystemic eosinophilic epitheliotropic disease in three donkeys

Multisystemic eosinophilic epitheliotropic disease (MEED) is a rare condition of equids characterized by eosinophilic infiltration of multiple organs. Clinical signs are variable depending on the affected organs. The most common clinical signs include chronic weight loss, diarrhoea and exfoliative dermatitis. Respiratory distress and raised liver enzymes are less frequently seen. The cause is unknown and the pathogenesis is poorly understood. There are less than 50 reported cases of horses with MEED. We now document the lesions in three donkeys with fluctuating or chronic loss of weight, lethargy, exfoliative dermatitis and peripheral eosinophilia. All three animals were euthanized due to poor prognosis and welfare concerns. Post-mortem examination revealed multiple white to tan, irregular masses composed of eosinophilic infiltrates, including eosinophilic granulomas in several organs, confirming the presence of MEED. To the best of our knowledge, MEED has not previously been reported in donkeys.

Fluid Analysis in the Equine Patient: Cerebrospinal, Synovial, and Peritoneal Fluids

Fluid analysis is an important part of the diagnostic work-up of equine patients presenting with disorders of the nervous system, musculoskeletal system, and abdominal cavity. Proper specimen handling and processing are paramount for complete and accurate interpretation of fluid samples. Normal cerebrospinal fluid is a low-cellularity, low-protein fluid requiring specific sample handling to ensure accurate results. Joint and abdominal fluid analyses are completed in practice or submitted for analysis to a reference laboratory. This article discusses fluid sample handling and processing considerations for the equine practitioner and reviews cytologic evaluation of normal and abnormal cerebrospinal, synovial, and peritoneal fluid samples.

Eosinophilic pancreatitis versus pancreatitis associated with eosinophilic gastroenteritis - a systematic review regarding clinical features and diagnosis

BACKGROUND

Over the past years, eosinophil infiltration involving the gastrointestinal tract and pancreas leading to eosinophilic pancreatitis, eosinophilic gastroenteritis and hypereosinophilic syndrome has been reported in the literature. We aimed to analyze and compare the features involving patients with eosinophilic pancreatitis and pancreatitis associated with eosinophilic gastroenteritis and to determine if there is a connection between the two disorders or if they in fact meet the diagnostic criteria for hypereosinophilic syndrome.

MATERIAL AND METHODS

The following search was performed in March 2019 on PubMed (MEDLINE) database using the medical terms "pancreatitis", "eosinophilic pancreatitis", "eosinophilic gastroenteritis" and "hypereosinophilic syndrome".

RESULTS

The search revealed 119 publications from 1970 onwards. A total of 83 papers were excluded, and the remaining 36 publications, consisting in case reports and case series, were analyzed. From 45 patients, 20 subjects with eosinophilic gastroenteritis developed pancreatitis, 20/45 had eosinophilic pancreatitis, and 5/45 hypereosinophilic syndrome involving the pancreas. There was no significant difference regarding clinical, laboratory and imaging features between the three groups, despite the multiple theories that explain the association of pancreatic and gastrointestinal eosinophilic infiltration. Although there was a strong resemblance between the three groups, histological evidence of eosinophilic gastrointestinal infiltration guided the treatment towards a less invasive way, while subjects with eosinophilic pancreatitis underwent pancreatic surgery to exclude potentially malignant lesions.

CONCLUSION

Although there are various theories that explain pancreatitis development in patients with eosinophilic gastroenteritis, hypereosinophilia diagnostic work-up should be taken into account in all patients with high number of blood eosinophils, even in those with eosinophilic pancreatitis in order to establish the diagnosis using a minimally invasive approach and to apply an adequate treatment.

Canine Indolent Nodular Lymphoma

Sixty-six cases of indolent canine lymphoid proliferation were reviewed. Age ranged from 1.5 to 16 years (median 9.0 years). Dogs of 26 breeds, plus 13 of mixed breeding or unknown lineage, were represented. B-Cell lymphomas (CD79a+) predominated. Marginal zone lymphoma (MZL), the largest group, involved lymph node (33 cases) and spleen (13 cases), with both tissues involved in five of these cases. Follicular lymphoma (FL) involved lymph nodes (five cases), and mantle cell lymphoma (MCL) occurred as solitary splenic masses (three cases). Nodal CD3+ T-zone lymphomas (TZL) (10 cases), were included since they resembled late-stage MZL at the architectural level. Two cases of marginal zone hyperplasia (MZH) were included to aid in differentiation of early MZL. Clonality status was determined in 54 cases by analysis of immunoglobulin heavy chain (IGH) and T-cell antigen receptor gamma (TCRG) gene rearrangement. Clonal rearrangement of IGH was detected in 28 of 35 MZL cases (80%), four of four FL cases (100%) and three of three MCL cases (100%). Concurrent cross lineage rearrangement of TCRG was detected in six MZL and two FL cases. Clonal rearrangement of TCRG was documented in five of eight TZL cases (63%). Limited survival data obtained for 18 dogs indicated that the B-cell lymphomas (MZL, MCL, and FL) and the T-cell lymphoma (TZL) were associated with indolent behavior and long survival. Although to the authors' knowledge, the true incidence of canine indolent lymphomas is unknown, the tumors are not rare and may have been underrecognized. Recognition of their architectural features, routine application of immunophenotyping, and molecular clonality assessment should alleviate this.

Clinical, Laboratory, and Histopathologic Features of Equine Lymphoma

Clinical, laboratory and tissue findings from 37 horses with lymphoma were investigated. Horses ranged in age from 0.3 to 20.5 years (median 5.0 years) and included 18 females and 19 males. Weight loss ( n = 25) and ventral edema ( n = 21) were the most common historical and physical abnormalities. The most common laboratory abnormalities were hyperfibrinogenemia ( n = 26), hypoalbuminemia ( n = 19), anemia ( n = 19), leukemia ( n = 14), hyperglobulinemia ( n = 13), and thrombocytopenia ( n = 13). Thirty-four tumors involved multiple lymphoid tissues and abdominal or thoracic organs, and 3 tumors were restricted to cutaneous and subcutaneous sites. Histopathologically, all tumors diffusely effaced normal lymph node architecture. Tumor cell morphology was heterogeneous in 17 tumors, and 8 tumors had marked histiocytic and multinucleated giant cell infiltrates. Extensive necrosis or focal fibrosis was present in 22 and 4 lymphomas, respectively. Staining of tumor sections with antibodies against CD3 and CD79α molecules resulted in classification of T-cell ( n = 26) or B-cell ( n = 7) origin. Four tumors could not be classified. Most T-cell tumors comprised small to medium CD3+ lymphocytes, whereas 5 of 7 B-cell tumors were infiltrated by numerous small T lymphocytes and classified as T-cell-rich B-cell lymphoma. Neither estrogen nor progesterone receptor expression was consistently identified by immunochemical assessment of tumor tissues. Fresh tumor cells from 6 horses bound antibodies reactive with equine CD4, CD5, CD8, CD21, or major histocompatibility class II molecules, confirming T-cell ( n = 5) or B-cell origin ( n = 1). These findings suggest that T-cell lymphoma is more common than B-cell lymphoma in horses and that inflammation, possibly from tumor cytokine production, is frequent.

Systemic and Eosinophilic Lesions in Rats with Spontaneous Eosinophilia (mes Rats)

The mes rat is from an inbred mutant colony of rats with spontaneous eosinophilia. In order to investigate the pathogenesis of the mes rat, the histopathology and hematology for 76 mes rats were examined at several weeks of age. Tissue eosinophilia developed at 8 weeks of age when the blood eosinophil was 500 cells per microliter or more. Subsequently, eosinophilia progressed with age, and splenic eosinophilopoiesis and erythropoiesis appeared simultaneously. Many inflammatory lesions were induced after 10 weeks of age when the blood eosinophils became 1,000 cells per microliter or more. Gastroenteritis and mesenteric lymphadenitis were seen in 44 of 47 (94%) and 31 of 47 (66%) rats, respectively, after 10 weeks of age. Aortitis that deteriorated with age was found in 19 of 39 (49%) rats after 12 weeks of age. Hepatic fibrosis was found in four rats that exhibited severe eosinophilia and anemia. These results are comparable to the features of a hypereosinophilic syndrome in humans and other animals.

Eosinophilic pancreatitis: Three case reports and literature review

Eosinophilic pancreatitis (EP) is a rare form of chronic pancreatitis characterized by localized or diffuse eosinophilic infiltration of the pancreas and elevated serum immunoglobulin E levels. EP is difficult to distinguish from pancreatic cancer on the basis of clinical symptoms and the results of auxiliary examination alone. A retrospective analysis of the clinicopathological characteristics and laboratory, imaging, and pathology results of 3 patients with EP, who were initially diagnosed with pancreatic malignancy, was performed. EP is an allergic disease with non-specific clinical manifestations that is difficult to distinguish from pancreatic cancer based exclusively on clinical symptoms and auxiliary examination, resulting in the need for invasive procedures to confirm the diagnosis. An increase in the eosinophil count in the peripheral blood and pathological examination are essential for the diagnosis of EP.

Comparative Pancreatic Pathology

Spontaneous pathologies of the pancreas are important causes of morbidity and mortality in some veterinary species and rare in others. As in human beings, the pancreas of most domestic and exotic animals is a composite organ with both endocrine and exocrine functions. The similarities between structure and function of porcine, canine, and human pancreata are such that the pig and dog serve as valuable models in basic and translational studies, most recently for efforts aimed at modeling pancreatitis and diabetes, developing functional and sustainable replacement of endocrine functions, and in imaging and manipulation studies.

This article will provide a brief review of spontaneous veterinary diseases and their underlying mechanisms and the morphological features that reflect these alterations. Several species- or breed-specific conditions and the effects of selected systemic diseases on the pancreas are also discussed. The contributions to our knowledge of pancreatic physiology and pathology by small mammal (rodent) and engineered animal models and the in-depth mechanisms homologous to those in the human pancreas are covered in other sections of this article.

Two Hundred Three Cases of Equine Lymphoma Classified According to the World Health Organization (WHO) Classification Criteria

Lymphoma is the most common malignant neoplasm in the horse. Single case reports and small retrospective studies of equine lymphomas are reported infrequently in the literature. A wide range of clinical presentations, tumor subtypes, and outcomes have been described, and the diversity of the results demonstrates the need to better define lymphomas in horses. As part of an initiative of the Veterinary Cooperative Oncology Group, 203 cases of equine lymphoma have been gathered from 8 institutions. Hematoxylin and eosin slides from each case were reviewed and 187 cases were immunophenotyped and categorized according to the World Health Organization classification system. Data regarding signalment, clinical presentation, and tumor topography were also examined. Ages ranged from 2 months to 31 years (mean, 10.7 years). Twenty-four breeds were represented; Quarterhorses were the most common breed ( n = 55), followed by Thoroughbreds ( n = 33) and Standardbreds ( n = 30). Lymphomas were categorized into 13 anatomic sites. Multicentric lymphomas were common ( n = 83), as were skin ( n = 38) and gastrointestinal tract ( n = 24). A total of 14 lymphoma subtypes were identified. T-cell–rich large B-cell lymphomas were the most common subtype, diagnosed in 87 horses. Peripheral T-cell lymphomas ( n = 45) and diffuse large B-cell lymphomas ( n = 26) were also frequently diagnosed.

Sézary Syndrome in a Cat

Sézary syndrome is an uncommon leukemic variant of cutaneous lymphoma in cats. This cat had recurrent dermatitis with erythematous, pruritic plaques. Multiple skin imprints and biopsy samples were obtained over a 6-month period, and histopathological findings were consistent initially with eosinophilic miliary dermatitis and later with erythema multiforme. One week before death, Sézary cells were identified in the peripheral blood that expressed cluster of differentiation (CD)3 and CD8 antigens. Massive infiltration of CD3+ lymphocytes was noted in the skin and multiple internal tissues by histopathological examination. This case demonstrates the difficulty in diagnosing cutaneous lymphoma early in the disease course.

Cellular basis of chronic obstructive pulmonary disease in horses

Chronic obstructive pulmonary disease (COPD) is an inflammatory obstructive disease of the airways characterized with hypersensitivity of the airway tissues to various allergens, most commonly the fungi contained in the poor-quality hay and straw bedding-Saccharopolyspora rectivirgula, Aspergillus fumigatus, and Thermoactinomyces vulgaris. It is manifested clinically in middle-aged horses with recurrent episodes of dyspnea, chronic cough, and their reduced athletic and working capacity. Pulmonary emphysema and lack of pulmonary collapse are the most common gross lesion. Pathohistological findings in horses with COPD are chronic bronchitis/bronchiolitis, with characteristic changes in lumen, mucosa, submucosa, and smooth muscle layer and alveolar emphysema, both distensive and destructive form. Increased immunoreactivity in lungs and tracheobronchial lymph nodes is also noted. Most common lesions seen on cytology imprint smears from tracheal bifurcation is thick, viscous, PAS-positive mucus that forms Curschmann's spirals. Dominant cell population consists of desquamated airway epithelial cells, as well as eosinophils, neutrophils, mast cells, erythrocytes, and alveolar macrophages. Primary pulmonary pathogens as well as potential contaminants and secondary infection agents were isolated bacteriologically from lung samples. All of the aforementioned findings correlate pointing to the fact that chronic bronchitis/bronchiolitis represents a basic substrate of COPD, which have combined inflammatory and immunological etiology, and emphysema is secondary to airway obstruction.

Severe pulmonary disease due to multisystemic eosinophilic epitheliotropic disease in a horse

Multisystemic eosinophilic epitheliotropic disease was diagnosed histologically in a 17-year-old Quarter Horse intact mare that was presented with a chronic history of respiratory distress. At necropsy, the lungs were poorly collapsed and the pulmonary parenchyma contained innumerable, discrete, spherical nodules in a miliary pattern. A few similar nodules were scattered in the liver and the renal lymph nodes. Histologically, these nodules consisted of fibrosing eosinophilic granulomas. Based on histologic findings and the absence of an etiologic agent, a diagnosis of multisystemic eosinophilic epitheliotropic disease was made.

Lymphosarcoma in a boar

A 14-month-old Yorkshire boar was examined. In the abdomen, two big tumour masses were found in the intestines. In addition, pale nodules occurred in the liver, kidneys, in and upon the spleen, in the wall of the heart and in the testicles. By immunohistochemistry tumour cells were positive for CD3, but negative for B-lymphocyte antigen and CD79. From these findings it was concluded that the boar was suffering from multicentric lymphosarcoma probably of T-cell origin.

Dexamethasone for treatment of multisystemic eosinophilic epitheliotropic disease in a horse

A 4-year-old Paint mare was examined because of respiratory tract infection, dermatitis, and weight loss of 2 months' duration. Initial examination revealed generalized pruritic dermatitis, ocular and nasal discharges, and stranguria. Laboratory abnormalities included leukopenia and hypoalbuminemia. Further examination of the respiratory tract revealed grade III of IV pharyngitis and pyogranulomatous pneumonia. Endoscopic examination of the bladder revealed a prolific mass at the junction of the bladder and urethra. Hypoproteinemia was suspected to be caused by protein-losing enteropathy. On histologic examination, skin, rectal, pharyngeal, and urethral biopsy specimens were characterized by infiltration of eosinophils and lymphocytes, and a diagnosis of multisystemic eosinophilic epitheliotropic disease was made. The horse improved following treatment with dexamethasone, trimethoprim-sulfamethoxazole, and an antihistamine and was discharged after 19 days of hospitalization. Treatment with dexamethasone was continued for 4 weeks after hospitalization but was then discontinued. Eight months after discharge, the horse was performing as a pleasure horse and did not require any medical treatment. Multisystemic eosinophilic epitheliotropic disease is typically associated with a poor prognosis in horses. The dermatitis, protein-losing enteropathy, and lower respiratory tract disease in this horse were consistent with previous reports; however, pharyngitis and urethritis have not, to our knowledge, been previously reported in horses with this disease.

Eosinophilic pancreatitis and increased eosinophils in the pancreas

Prominent eosinophilic infiltrates are an unusual finding in the pancreas. Eosinophilic pancreatitis is one rare etiology of pancreatic eosinophilia, but other described causes of eosinophilic infiltrates have also included pancreatic allograft rejection, pancreatic pseudocyst, lymphoplasmacytic sclerosing pancreatitis (LPSP), inflammatory myofibroblastic tumor, and histiocytosis X. In this study we describe the clinicopathologic features of three new cases of eosinophilic pancreatitis and conduct a retrospective 18-year institutional review of the myriad disease processes associated with pancreatic eosinophilia. In the files of the Johns Hopkins Hospital, <1% of all pancreatic specimens had been noted to show increased numbers of eosinophils. Eosinophilic pancreatitis itself was a rare etiology for pancreatic eosinophilia, with only one in-house case over the 18-year study period and two additional referral cases. Other disease processes associated with prominent eosinophilic infiltrates were more common and included pancreatic allograft rejection (14 cases), LPSP (5 of 24 total LPSP cases evaluated), inflammatory myofibroblastic tumor (4 cases), and systemic mastocytosis (1 case). Patients with eosinophilic pancreatitis showed two distinct histologic patterns: 1) a diffuse periductal, acinar, and septal eosinophilic infiltrate with eosinophilic phlebitis and arteritis; and 2) localized intense eosinophilic infiltrates associated with pseudocyst formation. All three patients with eosinophilic pancreatitis had peripheral eosinophilia, and all had multiorgan involvement. One patient with LPSP also had marked peripheral eosinophilia, and 5 of 24 LPSP cases demonstrated prominent eosinophilic infiltrates in the gallbladder, biliary tree, and/or duodenum. Notably, not all of these patients with LPSP with prominent eosinophils in other organs had increased eosinophils in the pancreas itself. These results emphasize the infrequent nature of pancreatic eosinophilia and its multiple potential disease associations. True eosinophilic pancreatitis, although a fascinating clinicopathologic entity, is one of the rarest causes of pancreatic eosinophilia.

Hypereosinophilic paraneoplastic syndrome in a cat with intestinal T cell lymphosarcoma

A 10-year-old, neutered female, domestic shorthair cat was presented with a recent history of weight loss, polydipsia, diarrhoea and vomiting. On physical examination, intestinal thickening and mesenteric lymph node enlargement were apparent. Clinical investigations revealed peripheral blood eosinophilia, eosinophilic abdominal effusion and eosinophilic mesenteric lymphadenitis. There was a temporary response to treatment with glucocorticoids but signs progressed and the cat was euthanased. On histology, there was eosinophilic infiltration and fibroplasia of intestine and mesenteric lymph nodes. Large aggregates of neoplastic round cells in the intestine and lymph nodes were identified as T lymphocytes using immunohistochemistry. A diagnosis of intestinal T cell lymphosarcoma was made. This case demonstrates that hypereosinophilic paraneoplastic syndrome may occur in cats with lymphosarcoma. Eosinophil chemotaxis may be a response to the production of interleukin-5 by neoplastic lymphocytes.

Leukoproliferative disorders in horses

Leukoproliferative disorders reported in horses include lymphoma, lymphocytic leukemia, plasma cell myeloma, granulocytic leukemia, monocytic leukemia, myelomonocytic leukemia, and eosinophilic leukemia. Lymphoma affects horses of all ages, whereas leukemias often occur in younger horses. Clinical signs are often nonspecific including depression, anorexia, fever, and weight loss. Specialized diagnostic techniques such as cytochemistry and immunophenotyping better define the cellular origin of leukoproliferative disorders, which is essential for developing appropriate therapeutic protocols and rendering an accurate prognosis.

Hypereosinophilic syndrome with Hodgkin's-like lymphoma in a ferret

Hodgkin's-like lymphoma involving the lung, mediastinum, liver, kidneys and mesenteric lymph nodes was diagnosed in a ferret. The diagnosis was based on the presence of an admixture of CD3+ small lymphocytes with smaller numbers of macrophages, eosinophils, and large, pleomorphic, frequently multinucleated, Reed-Sternberg-like cells which were immunoreactive to BLA.36 monoclonal antibody. In addition, the liver, pancreas, small intestine and lungs were infiltrated with moderate to large numbers of eosinophils, forming eosinophilic granulomas with occasional deposition of Splendore-Hoeppli material, supporting a diagnosis of hypereosinophilic syndrome. The concurrent diagnosis of hypereosinophilic syndrome and Hodgkin's-like lymphoma in this ferret provides further support to the concept that, in animals, multisystemic eosinophilic infiltrates may be caused by the abnormal proliferation of T lymphocytes, as has been demonstrated in man.