Post-transplant malignant neoplasia associated with cyclosporine-based immunotherapy: prevalence, risk factors and survival in feline renal transplant recipients.

The study objective was to compare the prevalence of malignant neoplasia in feline renal transplant recipients (n = 111) with a control population of cats that did not receive transplantation (n = 142); and to determine whether the development of post-transplant malignant neoplasia (PTMN) affects long-term survival. Twenty-five (22.5%) renal transplant recipients were diagnosed with PTMN, and of those 14 (56%) were diagnosed with lymphoma. The overall survival time in cats that developed PTMN following renal transplantation (median 646 days, IQR 433-1620 days) was not significantly different from the survival time in cats that did not develop PTMN (median 728 days, IQR 201-1942 days), although median survival after diagnosis of PTMN was only 13 days. Six control cats (4.2%) were diagnosed with malignant neoplasia. Compared to the control population, transplant cats had a 6.6 times higher odds of developing malignant neoplasia and a 6.7 times higher odds of developing lymphoma.

Feline visceral hemangiosarcoma.

BACKGROUND: Feline visceral hemangiosarcoma (HSA) is an uncommon tumor, and the clinical progression and outcome are rarely reported. HYPOTHESIS: The prognosis of feline visceral HSA is poor because of severe clinical signs, anemia, and a high rate of metastasis. ANIMALS: The medical records of 26 client-owned cats with visceral HSA were reviewed. METHODS: Multi-institutional retrospective study. RESULTS: The most common historical findings and clinical signs included lethargy, anorexia, respiratory difficulty, collapse, and vocalizing. Eighty-two percent of cats were anemic, and aspartate transaminase was increased in 53% of the study population. Metastatic lung disease was noted in 33% of affected cats. In 75% of the cats, abdominal ultrasonography identified a specific location of HSA. However, ultrasound identification of all multifocal lesions was successful only in 3/9 cats (33%). Tumor location was identified in the following organs: liver (35%), small intestine (31%), large intestine (31%), abdominal lymph node (31%), mesentery (27%), spleen (23%), lung (19%), omentum (12%), brain (8%), pancreas (8%), and diaphragm (8%). Multifocal HSA was noted in 77% of cats. Three cats received adjuvant chemotherapy (doxorubicin). Seventy-one percent of euthanized cats were euthanized within 1 day of diagnosis. The median survival time of the remaining cats (n = 6) was 77 days (range, 23-296 days). CONCLUSION AND CLINICAL IMPORTANCE: Feline visceral HSA is most often multifocal at the time of diagnosis. The prognosis appears poor, and the number of cats receiving chemotherapy is low.

Diagnosis and surgical management of ureteral calculi in dogs: 16 cases (1990-2003).

AIMS: To examine the clinical signs, laboratory and radiographic findings, surgical technique, ureterolith composition, and post-operative outcomes in dogs managed surgically for ureterolithiasis to determine whether surgical removal of ureteroliths in dogs resulted in a positive clinical outcome. METHODS: The medical record database of a university veterinary hospital in Pennsylvania, USA, was searched for dogs that underwent surgery to remove obstructive ureteral calculi between 1990 and 2003. Records were reviewed for signalment, clinical history and examination findings, radiographic and laboratory test results, surgical technique, and ureterolith analysis. Follow-up information was obtained from telephone interviews with owners or referring veterinarians, or by reviewing the medical record of subsequent hospital visits. RESULTS: Sixteen dogs were included in this study; ten were neutered females, two intact females and four castrated males. Abdominal radiography revealed ureteral calculi in 14/16 dogs, renal calculi in 8/16, cystic calculi in 8/16, urethral calculi in 1/16, renomegaly in 6/16 and renal mineralisation in 5/16. Ureterolith type included struvite in six dogs, calcium oxalate in five, calcium phosphate in one, and a mix of struvite, calcium phosphate and calcium oxalate in another. Compared to dogs with non-struvite ureteroliths, those with struvite ureteroliths had a higher pre-operative white blood cell (WBC) count (25.6, SD 7 vs 17.6, SD 6 x 103 cells/mul; p=0.046), and were more likely to have a purulent discharge from the ureteral incision noted at the time of surgery (p=0.015). Following discharge, 14/16 dogs were re-evaluated. Median survival time was 904 days (range 2-1,876). Two dogs required additional surgery on the urinary tract. Four dogs died or were euthanised because of azotaemia and clinical signs related to the urinary system or non-specific signs of illness (vomiting, lethargy) at 8, 90, 333 and 904 days post-operatively. CONCLUSIONS: Surgical management of ureteroliths was successful and resulted in good long-term survival in the majority of dogs examined in this small study population. Similar proportions of calcium oxalate and struvite ureteroliths were identified. CLINICAL RELEVANCE: The use of the ureteral surgery may increase as the frequency of diagnosis of ureteroliths in dogs increases.

Hypercalcemia following renal transplantation in a cat.

An 11-year-old 3.0-kg (6.6-lb) neutered male Persian was referred for renal transplantation. Serum total calcium concentration was slightly high prior to surgery, but the week after surgery, total and ionized calcium concentrations were extremely high, and a small mass was palpable on the right side of the trachea at the level of the thyroid and parathyroid glands. Exploratory surgery of the ventral aspect of the neck was performed, and a right external parathyroid mass was removed. One hour after surgery, the serum ionized calcium concentration was within reference limits, and the serum calcium concentration remained normal for the next 14 months without any specific treatment. The gross and histologic appearance of the mass, combined with the rapid decrease in serum calcium concentration following its removal, confirmed that the mass was a functional parathyroid adenoma. Although a common postoperative complication in people, hypercalcemia following renal transplantation appears to be a rare complication in cats. Surgery should be considered if the condition is a result of a parathyroid adenoma.

Hepatic microvascular dysplasia in dogs: a retrospective study of 24 cases (1987-1995).

Hepatic microvascular dysplasia (HMD) is a disease involving a microscopic shunting of blood through the liver without the presence of a macroscopic portosystemic shunt (PSS). Data was collected from medical records and telephone conversations with referring veterinarians and owners of 24 dogs diagnosed with HMD. Criteria for diagnosis included histopathological evidence of microvascular dysplasia on hepatic biopsy as well as surgical exploration and a normal mesenteric portogram to rule out a macroscopic PSS. Dogs with HMD frequently have less severe clinical signs and a better long-term prognosis than do those with a PSS that are managed medically.

Gastrointestinal emergencies.

The animal with a surgical gastrointestinal emergency usually requires a rapid, thorough physical examination with concurrent resuscitation. As the diagnosis is being made, the animal must be made as stable as possible before undergoing general anesthesia. During surgery, there must be a critical evaluation of gastrointestinal viability and the use of precise technical skills to achieve the best outcome. Adept postoperative management, including careful monitoring and an index of suspicion for potential complications, is vital.

A practical approach to hemoperitoneum in the dog and cat.

Hemoperitoneum can occur in animals of any age and can result from many different disease processes. Neoplastic and traumatic conditions are the most common causes. Many of these patients present with hemodynamic instability but stabilize with rational intravenous fluid therapy and abdominal counterpressure. Surgical exploration of the abdomen is indicated in many situations. Surgical therapy is aimed at resection or control of the bleeding focus, removal of any devitalized tissue, and biopsy of additional sites of suspicion. Optimal treatment for all patients with hemoperitoneum frequently requires advanced critical care, anesthesia, and surgical techniques. Finally, the treatment outcome is variable and dependent on the underlying cause and its severity.

Management of hypertension controls postoperative neurologic disorders after renal transplantation in cats.

OBJECTIVES: To determine the prevalence and describe the management of hypertension and central nervous system (CNS) complications after renal transplantation in cats. We also compared the prevalence of CNS complications between cats monitored and treated for postoperative hypertension and a previously described, historical control group of cats not monitored or treated for postoperative hypertension. STUDY DESIGN: Retrospective clinical study. ANIMALS OR SAMPLE POPULATION: A total of 34 client-owned cats that received renal allografts for the treatment of end-stage renal failure. METHODS: Medical records were reviewed. Data obtained included preoperative and postoperative systolic blood pressures, antihypertensive therapy, response to treatment, neurologic signs, and clinical outcome. The results were compared with a historical control group of feline renal allograft recipients that were neither monitored nor treated for postoperative hypertension. RESULTS: Severe postoperative hypertension occurred in 21 of 34 of cats. Hypertension was treated in all 21 cats with subcutaneously administered hydralazine which reduced systolic blood pressure to less than 170 mm Hg in 15 minutes in 20 of 21 cats; hydralazine produced hypotension in one cat and failed to control hypertension in 1 cat. After transplantation, seizures were observed in one cat and other neurologic complications (stupor, ataxia, and central blindness) were observed in three cats. The prevalence of seizures and neurologic complication-related deaths after transplantation was significantly reduced with treatment of postoperative hypertension. CONCLUSIONS AND CLINICAL RELEVANCE: Hypertension is a major contributing factor to postoperative seizure activity after renal transplantation in cats; treatment of hypertension reduces the frequency of neurologic complications.

Acute toxoplasmosis following renal transplantation in three cats and a dog.

Three cats and 1 dog that had undergone renal transplantation because of end-stage renal disease were examined because of complications 3 to 6 weeks after surgery. One cat died prior to treatment of the complications; Toxoplasma cysts were found in sections of the renal allograft, and Toxoplasma tachyzoites were found in other organs. The other 2 cats and the dog died despite treatment, and protozoal cysts, as well as tachyzoites, were identified in other organs but not within the allografts, suggesting that reactivation of latent infection following immunosuppression was the most likely cause of disseminated toxoplasmosis. These cases illustrate that toxoplasmosis can be a fatal complication in renal transplant recipients. We currently recommend that feline and canine donors and recipients undergo serologic testing for toxoplasmosis prior to surgery. In addition, we suggest that seropositive donors not be used for seronegative recipients and that seropositive recipients and that seropositive recipients be monitored closely after surgery for clinical signs of toxoplasmosis.

Possible hemolytic uremic syndrome in three cats after renal transplantation and cyclosporine therapy.

OBJECTIVE: To describe the clinical history of 3 cats with possible hemolytic uremic syndrome (HUS) after renal transplantation. STUDY DESIGN: This case series documents historical findings, physical examination findings, clinical pathologic features, necropsy and histopathologic findings of 3 cats with possible HUS. RESULTS: Two cats had chronic renal failure; 1 cat had acute renal failure secondary to ethylene glycol toxicity. A renal transplant was performed in each of the 3 cats without obvious problems. Complications that would support a diagnosis of HUS, including anemia, thrombocytopenia, and azotemia occurred within 24 hours in 1 cat, within 8 days in a second cat, and 2 months after transplantation in the third cat. In 2 cats, HUS was likely secondary to cyclosporine immunosuppression. In the third cat, HUS may have been secondary to allograft rejection. Renal biopsies from all 3 cats were suggestive of HUS. CONCLUSION AND CLINICAL RELEVANCE: In human beings, HUS in transplant recipients may occur secondary to immunosuppressive drugs, vascular rejection, or recurrence of original disease. Graft loss occurred in all 3 cats in this study and the mortality rate was 100%. Clinicians caring for these patients need to be aware of this disorder because early recognition and treatment is critical in the management of post-transplant HUS.

Central nervous system disorders after renal transplantation in cats.

OBJECTIVE: This study describes the incidence and severity of postoperative central nervous system (pCNS) disorders in feline renal transplant recipients. STUDY DESIGN: A retrospective study based on the medical records of cats that received renal allografts from 1987 to 1996. ANIMALS OR SAMPLE POPULATION: Fifty-seven client-owned cats received renal allografts for the treatment of renal failure. METHODS: The frequency, duration, severity, and treatment of episodes of pCNS disorders were recorded from the medical records. RESULTS: Twelve (21%) of 57 cats had pCNS disorders 1 hour to 5 days after the surgical procedure. Seven cats survived; four had single or multiple seizure episodes, and two had seizure episodes or disorientation followed by a period of coma. One cat became temporarily ataxic and blind after restraint for venipuncture. Five cats died; all had episodes of disorientation or seizures, or both, that progressed to a nonrecoverable comatose state, respiratory arrest or cardiac arrest, or both. There were no significant differences between the two groups in preoperative serum creatinine, blood urea nitrogen, or cholesterol levels, and intraoperative blood pressure measurements. There were no significant differences in the postoperative serum glucose levels, electrolytes levels, or osmolality between the two groups. The cats with pCNS disorders had a mean preoperative trough cyclosporine A (CyA) whole blood level of 429 ng/mL; cats without pCNS disorders had a significantly (P = .0116) higher mean preoperative trough CyA whole blood level of 736 ng/mL. CONCLUSION: Central nervous system disorders are a common and often fatal complication of renal transplantation in cats. CLINICAL RELEVANCE: Recognition of pCNS disorders, and possible causes, will help develop hypotheses to investigate the problem.

Endogenous benzodiazepine activity in the peripheral and portal blood of dogs with congenital portosystemic shunts.

OBJECTIVE: The purpose of this study was to determine whether an endogenous benzodiazepine receptor ligand (EBZ) was present in the arterial and portal blood of dogs with congenital portosystemic shunts (CPSS). STUDY DESIGN: The presence or absence of an EBZ was determined by the collection of systemic and portal blood from dogs with CPSS. ANIMALS: Fifteen client-owned dogs with a confirmed CPSS. All dogs had historical signs compatible with hepatic encephalopathy. Eight healthy dogs were used as controls. METHODS: In all dogs, systemic blood samples were collected after they were anesthetized. Portal blood samples were collected intraoperatively. EBZ was measured by radioreceptor assay. RESULTS: In 10 of 15 dogs, the portal blood concentration of EBZ was significantly elevated compared with normal dogs (mean, 13.2 +/- 18.55 ng/mL). Five dogs had elevated systemic blood EBZ levels (mean, 8.2 +/- 16.08 ng/mL). Eleven of 15 dogs had a higher portal than systemic blood concentration of EBZ. In contrast, control dogs had extremely low EBZ concentrations detected in their portal blood (mean, 0.16 +/- 0.3 ng/mL) and systemic blood (0 ng/mL). The mean portal and systemic blood concentrations in dogs with CPSS were significantly greater than in control dogs (P < .05). CONCLUSIONS: Elevated blood levels of EBZ were found in dogs with CPSS. The portosystemic gradient noted in 11 dogs suggests the gastrointestinal tract as a possible source for the endogenous ligand. CLINICAL RELEVANCE: Generalized motor seizures have been reported in dogs after surgical correction of CPSS. If the presence of a CPSS results in stimulation of brain receptors for benzodiazepines, post-CPSS ligation seizures may result from a withdrawal of EBZ after ligation of the portosystemic shunt.

Selective alterations of cerebrospinal fluid amino acids in dogs with congenital portosystemic shunts.

Numerous studies suggest that modifications in concentrations of both excitatory and inhibitory amino acids are implicated in the pathophysiology of portal-systemic encephalopathy (PSE), a neuropsychiatric disorder associated with chronic liver disease in humans. In this study, amino acid levels were measured by High Performance Liquid Chromatography (HPLC) in Cerebrospinal Fluid (CSF) of 10 dogs (age range: 3 mo.- 3 yr 4 mo.) exhibiting a congenital portal-systemic shunt, either intra or extra-hepatic, and 8 age-matched control dogs who showed no signs of hepatic or neurologic disorders. Dogs with congenital shunts manifested signs of encephalopathy such as disorientation, head pressing, vocalization, depression, seizures and coma. CSF from dogs with congenital shunts contained significantly increased amounts of glutamate (2 to 3-fold increase, p<0.01), glutamine (6-fold increase, p<0.05) and aromatic amino acids (phenylalanine, tyrosine and tryptophan) compared to CSF of control dogs. Concentrations of GABA and branched chain amino acids (valine, leucine, isoleucine) were within normal limits. Modifications of brain glutamate (an excitatory amino acid) as well as tryptophan (the precursor of serotonin) could contribute to the neurological syndrome characteristic of congenital PSE in dogs.

Infectious pericardial effusion in five dogs.

The medical records of five dogs diagnosed with infectious pericardial effusion were reviewed. Clinical signs included anorexia, depression, respiratory distress, abdominal distension, collapse, coughing, and vomiting. Anemia and leukocytosis were present in three dogs. Grass awn migration was confirmed as the cause of the pericardial effusion in two dogs and suspected in the other three. Surgery, followed by continuous chest drainage, and appropriate antibiotic therapy was the treatment in four dogs. Chest drains were removed within 4 days of surgery. One dog did not have chest drainage after surgery. Antibiotic treatment was continued for up to 6 months. The dogs were monitored postsurgically for a period ranging from 3 to 24 months. All dogs recovered well without apparent complications.

The case of The Case of the Midwife Toad.

The facts concerning Kammerer's case are reviewed. Koestler's view that Krammerer was unjustly accused is presented and shown to be incorrect.