Hypoglycemia and Tumor Lysis Syndrome Associated with peritoneal Mesothelioma in a Horse

Abstract

A n 11-year-old Lipizzaner mare was referred for lethargy, abdominal distention, coughing, and weakness of 1 month's duration. The mare had been regularly dewormed and vaccinated against tetanus, influenza, and Eastern and Western equine encephalitis. Serum agar gel immunodiffusion assay for equine infectious anemia was negative.The mare was weak, lethargic, and mildly dehydrated. Abdominal distention was prominent (Fig 1), and borborygmi were absent. Mucous membranes were pale with a capillary refill time of 3.5 seconds. Heart (86 beats/min) and respiratory (40 breaths/min) rates were increased, and rectal temperature was 99.8uF. Body weight was 605 kg, but the mare was judged to be thin. Ventral abdominal subcutaneous edema was evident. Per rectum abdominal palpation identified a nongravid uterus.Moderate anemia (packed cell volume, 21%), mild lymphopenia, and hyperfibrinogenemia (0.5 g/dL; reference range, 0.1-0.4 g/dL) were present on the CBC. Serum biochemical analysis identified hypoglycemia (glucose, 47 mg/dL; reference range, 72-114 mg/dL), azotemia (BUN, 89 mg/dL; reference range, 8-27 mg/ dL; creatinine 5 8.8 mg/dL, reference range, 0.6-1.8 mg/dL), hyponatremia (sodium, 121 mmol/L; reference range, 132-144 mmol/L), hypochloremia (chloride, 86 mmol/L; reference range, 94-102 mmol/L), hyperkalemia (potassium, 6.3 mmol/L; reference range, 2.7-4.9 mmol/L), hypoproteinemia (protein, 4.8 g/dL; reference range, 4.9-6.9 g/dL), hypoalbuminemia (albumin, 2.1 g/dL; reference range, 2.5-4.2 g/dL), hypocalcemia (calcium, 9.9 mg/dL; reference range, 10.7-13.4 mg/dL), hyperphosphatemia (inorganic phosphate, 13.9 mg/dL; reference range, 1.9-5.4 mg/dL), hypertriglyceridemia (triglyceride, 2,720 mg/dL; reference range, 4-44 mg/ dL), unconjugated hyperbilirubinemia (3.7 mg/dL; reference range, 0.1-1.9 mg/dL), and increased serum enzyme activities (CK, 3,147 U/L; reference range, 90-565 U/L; aspartate aminotransferase (AST), 2,268 U/L; reference range, 205-555 U/L; lactate dehydrogenase (LDH), 32,582 U/L; reference range, 520-1,480 U/L; gamma glutamyl transferase (GGT), 59 U/L; reference range, 12-45 U/L). Urinalysis indicated dilute urine (urine specific gravity [USG], 1.016) and hyaline casts (15 to 20 casts per low power field) were observed. The bladder was normal on endoscopic examination.Abdominal ultrasonography identified a large volume of anechoic abdominal fluid and revealed irregular cauliflower-like masses adherent to the abdominal wall at many locations, evidently fused to the peritoneum and characterized by mixed echogenicity (Fig 2). Other smaller masses were identified on the surface of the mesentery and adjacent to the dorsal aspect of the spleen. Abnormalities were not seen in the liver, kidneys, and intestines. Mild to moderate anechoic bilateral pleural effusion was observed.Abdominocentesis yielded a large volume of serosanguineous peritoneal fluid (PF) characterized by a normal nucleated cell count (659 nucleated cells/mL), moderately increased protein concentration (3.2 g/dL), and a hematocrit of 3%...

Case Series

“…Seizures and cardiac arrhythmias associated with ATLS are usually attributed to metabolic changes, including hyperkalemia, hyperphosphatemia, and hypocalcemia (Davidson et al 2004). Similar metabolic derangements have been described in cats, dogs, and a horse with ATLS (Calia et al 1996;LaCarrubba et al 2006;Laing and Carter 1988;Mylonakis et al 2007;Vickery and Thamm 2007), but histopathology has not been routinely reported. A single series of three canine ATLS cases revealed generalized microthrombi in the necropsy specimens of two dogs (Laing and Carter 1988).…”

“…Clinically significant ATLS, with end-organ compromise, occurs in approximately 5% of all patients with hematologic malignancies (Hochberg and Cairo 2008) and in up to 25% of highrisk patients, including those with T-cell acute lymphoblastic leukemia and Burkitt's lymphoma (Coiffier et al 2008). Acute tumor lysis syndrome also develops secondary to hematopoietic malignancies and solid tumors in veterinary species (LaCarrubba et al 2006;Radaelli et al 2009), although the overall incidence is unknown. Life-threatening complications of ATLS include acute renal failure, cardiac arrhythmias, neurologic perturbations, and metabolic acidosis (Davidson et al 2004;Hochberg and Cairo 2008).…”

Acute B-lymphoid leukemia in a mare: a case report

“…Blood cultivation was not done in this mare. The other possibility is tumor lysis syndrome (TLS), which was described in a horse with peritoneal mesothelioma (LaCarrubba et al, 2006). TLS is a well recognized oncologic emergency in humans characterized by severe metabolic derangements such as acute renal failure, hyperkalemia, hyperphosphatemia, hypokalcemia.…”

Disseminated lipid-rich peritoneal mesothelioma in a horse

“…Neoplastic transformation of these cells is an infrequent occurrence in domestic animals. 3,8 There have been a small number of reports of mesothelioma in horses, including tumors arising within the pleural cavity, 6,7 peritoneal cavity, 4,10 and pericardium, 12 and those that had spread to involve more than one of these sites. 6,13,14 The ages of the horses ranged from 2 to 27 years.…”

“…The clinical presentation depended on the site affected; for example, tumors arising in the peritoneal cavity typically produced marked abdominal distension due to ascites, as in other species. 4,8,10 Mesotheliomas have been classified into 3 main histological types: epithelioid, biphasic, and sarcomatoid. 8 Additional epithelioid variants include tubopapillary, acinar, polygonal, microcystic, clear cell, deciduoid, desmoplastic, and lymphohistiocytic mesotheliomas.…”