Adipocytes in synovial fluid cytology: An approach for diagnosing synovial lipomatosis.

A 2-year-old neutered male bullmastiff dog was presented with chronic left hind limb lameness. Physical examination revealed left stifle effusion and medial buttress without cranial tibial thrust. Radiographs showed joint effusion and new bone formation at the patella apex. Magnetic resonance imaging showed increased synovial fluid, widening of the joint space, abnormal infrapatellar fat body and thinning of the cranial cruciate ligament. Synoviocentesis and cytologic evaluation of synovial fluid revealed marked mononuclear inflammation with abundant fatty tissue, suggesting synovial lipomatosis in conjunction with the imaging findings. The disease was confirmed histologically after sampling the lesion during arthrotomy. Synovial lipomatosis, characterized by extensive synovial adipose tissue proliferation of the synovial membrane, is a rare "tumor-like" disorder that usually affects the stifle. Although the etiology remains unclear, joint trauma, inflammation, instability, and lipid abnormalities have been proposed as causes. Inflammatory factors may promote synoviocyte and adipocyte hyperplasia that perpetuate the process. Surgical removal may be suggested to eliminate triggers and prevent future recurrences. The report provides the first cytological description of adipocytes in synovial fluid associated with the diagnosis of synovial lipomatosis in dogs. This case report underscores the potential effectiveness of cytologic analysis of synovial fluid smears, in combination with magnetic resonance imaging (MRI), for diagnosing this condition and reducing complications associated with arthrotomy for sampling purposes. Additionally, the case highlights that synovial lipomatosis should be considered as a potential differential diagnosis for synovial masses in dogs. Further cases are needed to validate these observations in veterinary medicine.

Spinal epidural and synovial lipomatosis in a 3-year-old Eurasian dog receiving sustained steroid therapy.

This report describes a spinal cord epidural and synovial lipomatosis in a 3-year-old neutered male Eurasian dog. This dog presented for ambulatory paraparesis and was previously treated with immunosuppressive dosages of prednisolone for 2 years. Computed tomography (CT) myelography and magnetic resonnance imaging (MRI) images identified dorsal compression of the thoraco-lumbar spinal cord by hypertrophic epidural fat. Histological examination identified extensive well-differentiated mature adipose tissue in the subepithelial area of the tarsal synovium. Prednisolone is a reported predisposing factor in humans with lipomatosis.

Extensive Fatty Replacement of the Pancreas (Pancreatic Lipomatosis) in a Dog.

A 12-year-old neutered female mixed-breed dog was referred for occasional vomiting that had increased progressively in frequency over the past 3 months. Palpation of the abdomen revealed a firm mass of unknown aetiology, located within the cranial to mid abdomen, while abdominal surgical exploration revealed a well-defined abdominal mass of pancreatic origin. The pancreatic mass caused lateral displacement of the duodenum as well as medial displacement of the pylorus, resulting in impairment of pyloric outflow. Further examination revealed a firm, poorly vascularized and coarsely lobulated structure. The histopathological findings were consistent with severe pancreatic lipomatosis and atrophy. Immunohistochemically, the remnant pancreatic cells were positive for cytokeratins AE1/AE3 and glucagon, and negative for insulin. Routine follow-up with the referring veterinarian showed no evidence of postoperative complications, but the dog continued to deteriorate further and died despite medical management. Pancreatic lipomatosis is a rare condition in small animal practice. The aetiology or predisposing factors have not been identified in animals.

Diffuse Infiltrative Colonic Lipomatosis in a Vietnamese Pot-bellied Pig.

Diffuse infiltrative gastrointestinal lipomatosis (DIGIL) is characterized by widespread proliferation of adipose tissue within the submucosal and subserosal layers of the gastrointestinal tract. Here we describe a case of diffuse infiltrative colonic lipomatosis in a 3-year-old male Vietnamese pot-bellied pig. Gross anatomical changes included obesity with sparse small intestinal contents and no colonic contents. The colonic lumen was narrowed and the colonic wall was diffusely thickened (∼5 mm), white, homogeneous and soft. Other findings were vesical uroliths and mild fibrinous pneumonia. Histologically, the colonic submucosa and muscle layers were expanded and almost completely replaced by sheets of adipose tissue admixed with scant fibrovascular tissue. Other minor changes included mild fibrinous pneumonia, splenic lymphoid depletion and testicular atrophy. The colonic changes in the current case are consistent with those described for DIGIL. This is a rare condition in human beings and animals and has never been described in pigs.

Liposarcoma or invasive lipomatosis in flower horn fish, hybrid cichlid: clinical, radiological, ultrasonographical and histopathological study.

Liposarcoma or invasive lipomatosis affecting three indoor aquarium fish (flower horn fish, hybrid cichlid) is characterized, by the presence of mature adipocytes of variable sizes and by an invasive behaviour, which affected internal organs and eyes of all cases. Detailed macroscopic, radiological, ultrasonographical and histopathological features are presented. All fish had bilateral exophthalmia with some masses around the eyes. Ultrasonography confirmed the presence of hyperechoic masses in the eyes. Histopathology of all cases described the presence of variable-sized adipose cells in the eyes. The suggested diagnosis is well-differentiated liposarcoma or invasive lipomatosis. This is the first report of liposarcoma or invasive lipomatosis in flower horn fish, hybrid cichlid.

Diffuse Infiltrative Gastrointestinal Lipomatosis in a Guinea Pig (Cavia porcellus).

An intact adult male guinea pig (Cavia porcellus) went into cardiopulmonary arrest during a surgical procedure, and efforts at resuscitation were unsuccessful. Gross examination revealed a gastric rupture along the greater curvature of the stomach, which was associated with free blood and ingesta in the abdominal cavity, and a 2-cm nodular, partially circumferential, soft-to-firm mass within the pyloric region. Histologically, the pyloric mass was composed of sheets of infiltrative adipocytes expanding the muscular wall. Similar infiltrative sheets of adipocytes were present adjacent to the rupture site and within the small intestine, cecum, and colon. These findings are consistent with diffuse infiltrative lipomatosis, an exceedingly rare condition in human and veterinary species. This report is the first description of this rare disease in guinea pigs, and the concurrent involvement of both the stomach and intestines has not been reported in any veterinary species.

Abdominal lipomatosis with secondary self-strangulation of masses in an adult rhesus macaque (Macaca mulatta).

An 10-y-old, intact male rhesus macaque (Macaca mulatta) presented for bilateral scrotal swelling and a distended abdomen. A soft mass in the left upper quadrant of the abdomen was palpated. A barium study did not reveal any gastrointestinal abnormalities. Exploratory laparotomy revealed a large (1.25 kg, 15.0 × 13.0 × 9.5 cm), red and tan, soft, circumscribed, spherical mass within the greater omentum and 10 to 20 smaller (diameter, 1 to 4 cm), soft to firm masses in the mesentery and greater omentum. The resected mass was a self-strangulating abdominal lipoma, a pedunculated neoplasm composed of white adipocytes arising from peritoneal adipose tissue undergoing secondary coagulation necrosis after strangulation of the blood supply due to twisting of the mass around the peduncle. The smaller masses were histologically consistent with simple or self-strangulating pedunculated abdominal lipomas. The macaque presented again 9 mo later with a firm, 5.0-cm mass in the midabdomen, with intestinal displacement visible on radiographs. Given this animal's medical history and questionable prognosis, euthanasia was elected. Necropsy revealed numerous, multifocal to coalescing, 1.0- to 15.0-cm, pale tan to yellow, circumscribed, soft to firm, spherical to ellipsoid, pedunculated masses that were scattered throughout the mesentery, greater omentum, lesser omentum, and serosal surfaces of the gastrointestinal tract. All of the masses were pedunculated abdominal lipomas, and most demonstrated coagulation necrosis due to self-strangulation of the blood supply. To our knowledge, this report is the first to describe abdominal lipomatosis with secondary self-strangulation of masses in a rhesus macaque.

Metastatic uterine adenocarcinoma and hepatic lipomatosis in a llama (Lama glama).

A 6-year-old, female llama (Lama glama) presented with progressive anorexia and ascites. Postmortem examination revealed an infiltrative uterine adenocarcinoma with widespread metastases. The neoplasm completely replaced and infiltrated the myometrium of the uterine body and cervix and metastasized largely to the serosal surfaces of the peritoneal cavity. Histopathology identified a highly invasive growth of neoplastic cells in solid packets or tubular arrangements and marked fibroplasia. No bovine or llama papillomavirus DNA was detected intralesionally by polymerase chain reaction.

Abdominal lipomatosis attributed to tall fescue toxicosis in deer.

Five adult female Eld's deer died acutely or were euthanatized because of clinical signs including anorexia, signs of depression, and uremia. On necropsy, these deer had large masses of necrotic abdominal fat constricting the ureters, causing hydroureter and hydronephrosis. The herd from which these deer originated was maintained on pastures consisting primarily of tall fescue, samples from which were subsequently confirmed to be infected with an endophytic fungus that is known to cause similar lesions in cattle. A retrospective study of deaths in this herd revealed a sharp increase in incidence of abdominal lipomatosis since 1994. Physical examinations on the herd revealed > 90% of females to be affected. Endophyte-infected tall fescue forage was concluded to be a major factor in the development of lipomatosis in these deer. Other contributing factors were considered. Lesions caused by endophyte-infected fescue can be severe, and this disease can develop in nondomestic species.

Lipomatous infiltration of the canine salivary gland.

Benign connective tumours of the canine salivary glands are rare. This report describes lipomatous infiltration of parotid or submandibular salivary glands in seven dogs in which the glands were enlarged as a result of infiltration by fat cells; they appeared to have been successfully treated by local excision. The precise cause of the lipomatous infiltration in the dogs is unclear but different causes of similar lesions in humans are discussed.

Epidural lipomatosis in a six-year-old dachshund.

A six-year-old female dachshund was examined because of intermittent lameness in its left pelvic limb and periodic back pain. Myelography, epidurography and computed tomography (CT) revealed a dorsal displacement of the dural sac in the lumbosacral region caused by a soft tissue mass which had the specific density of fat. The mass was removed via a dorsal laminectomy in the lumbosacral area and a histological examination confirmed that it was adipose tissue. The clinical signs resolved after the surgery and a follow-up CT five months later showed no evidence of compression of the dural sac. The diagnosis of epidural lipomatosis in this dog was based on the clinical findings, the results of diagnostic imaging, and the surgical and histological findings, all of which revealed many similarities with epidural lipomatosis in man.

Multicentric intramuscular lipomatosis/fibromatosis in free-flying white-fronted and Canada geese.

Over a period of 9 yr, seven white-fronted geese (Anser albifrons) and one Canada goose (Branta canadensis) with multiple intramuscular mesenchymal tumors were encountered in Saskatchewan (Canada) and one similarly affected Canada goose was seen on Prince Edward Island (Canada). The tumors in these birds consisted either of adipose tissue, fibroblastic tissue, or a mixture of both types of tissues. The high prevalence of this condition in white-fronted geese suggested a genetic influence.

[Accumulated occurrence of lipomatosis in a cattle herd in Assiut (Egypt)]. / Gehäuftes Auftreten von Lipomatose in einer Rinderherde in Assiut (Agypten).

A total number of 30 native breed cows were used in this investigation. Ten animals were clinically healthy and kept as control, while 20 diseased cows were selected according to rectal findings. At the beginning of the disease, the cows appeared obese with marked deposition of fat in the subcutaneous tissue at the lumbosacral area, later on they became emaciated. Additional signs were digestive disturbance in form of diarrhea or constipation and tympany. Rectal examination revealed hard irregular masses of various size which were palpated in the pelvis, the perirenal area around the colon and the rectum. More information about the nature and character of the lesions were taken from slaughtered cows. Biochemical analysis, including total lipids, cholesterol triglycerides and creatine kinase, were carried out in both healthy and diseased cows. In advanced cases of bovine lipomatosis hyperlipemia and hypercholesterolemia as well as increased creatine kinase values were constant findings. The aetiology of this disease is still unknown.