Hypophosphatemia and Hemolytic Anemia Associated With Diabetes Mellitus and Hepatic Lipidosis in Cats

Hypophosphatemia associated with hemolytic anemia was diagnosed in five cats with diabetes mellitus and in one cat with idiopathic hepatic lipidosis. The hematocrit began decreasing within 24 to 48 hours after documented hypophosphatemia in each case. The anemia resolved in all five surviving cats. Because of the temporal relationship and lack of other detectable causes, hemolytic anemia was presumed to be caused by hypophosphatemia. There were increased Heinz bodies in three of six hypophosphate-mic cats during episodes of hemolysis. Intravenous potassium phosphate administration corrected the hypophosphatemia in four of five cats. The effective dosages of intravenous phosphate ranged from 0.011 to 0.017 mmol of phosphate/kg/h for 6 to 12 hours. Hypocalcemia (5.4 to 8.7 mg/dL) occurred in four of five cats treated with intravenous phosphate; however, only one cat developed clinical signs attributable to hypocalcemia. Based on this retrospective study, we recommend monitoring serum phosphorus concentration every 6 to 12 hours in cats likely to become hypophosphatemic. Treatment of hypophosphatemia in cats is warranted because of the apparent increased susceptibility of cats to hypophosphatemia-induced hemolysis. Cats with severe hypophosphatemia (≤1.5 mg/dL) should be given oral or parenteral phosphate if contraindications do not exist. (Journal of Veterinary Internal Medicine 1993; 7:266–271. Copyright © 1993 by the American College of Veterinary Internal Medicine.)     

Hypophosphatemia in Cats After Renal Transplantation

Objective— To report the prevalence of hypophosphatemia after renal transplantation in a historical cohort of cats. Design— Case series. Animals— Cats (n=86) that received a renal allograft. Methods— Medical records (January 200–June 2006) were reviewed. Signalment, clinical signs, pre‐ and postoperative diet, pre‐ and postoperative clinicopathologic variables, renal histopathology, and outcome were retrieved. Prevalence, onset, duration, treatment and associated clinical signs of hypophosphatemia were recorded. A χ² test was used to compare hemolysis frequency between cats with normal serum phosphorus concentration or a single spurious low serum phosphorus concentration for <24 hours duration (group 1) and confirmed hypophosphatemia for >24 hours (group 2). A Cox proportional hazards model was used to evaluate the effects of hypophosphatemia on survival while controlling for other potentially confounding variables (age, sex, weight, body condition score, and pre‐ and 24 hours postoperative clinicopathologic variables). Results— Eighty‐six cats (mean age, 7.7 years) were identified. Hypophosphatemia occurred in 32 cats (37%), with a median onset of 2 days and median duration of 4 days. Treatment was initiated in 48 (56%) of hypophosphatemic cats. Survival and hemolysis frequency was not significantly different between groups, and no risk factors were identified. Conclusion— Hypophosphatemia occurs in cats after renal transplantation and does not affect survival. Clinical Relevance— The clinical importance of hypophosphatemia in renal transplant recipients remains unknown.     

Effect of continuous intravenous administration of a 50% dextrose solution on phosphorus homeostasis in dairy cows

OBJECTIVE: To determine the effect of continuous IV administration of 50% dextrose solution on phosphorus homeostasis in lactating dairy cows. DESIGN: Clinical trial. ANIMALS: 4 multiparous Jersey cows. PROCEDURES: Cows were administered 50% dextrose solution IV (0.3 g/kg/h [0.14 g/lb/h]) for 5 days. Plasma concentrations of glucose, immune-reactive insulin (IRI), and phosphorus were determined before, during, and for 72 hours after dextrose infusion. Phosphorus intake and losses of phosphorus in urine, feces, and milk were determined. Each cow received a sham treatment that included instrumentation and sampling but not administration of dextrose. RESULTS: Plasma glucose, IRI, and phosphorus concentrations were stable during sham treatment. Plasma phosphorus concentration decreased rapidly after onset of dextrose infusion, reaching a nadir in 24 hours and remaining less than baseline value for 36 hours. Plasma phosphorus concentration increased after dextrose infusion was stopped, peaking in 6 hours. Urinary phosphorus excretion did not change during dextrose infusion, but phosphorus intake decreased because of reduced feed intake, followed by decreased fecal phosphorus loss and milk yield. Rapid changes in plasma phosphorus concentration at the start and end of dextrose infusion were temporally associated with changes in plasma glucose and IRI concentrations and most likely caused by compartmental shifts of phosphorus. CONCLUSIONS AND CLINICAL RELEVANCE: Hypophosphatemia developed in response to hyperglycemia or hyperinsulinemia in dairy cows administered dextrose via continuous IV infusion. Veterinarians should monitor plasma phosphorus concentration when administering dextrose in this manner, particularly in cows with decreased appetite or preexisting hypophosphatemia.     

Hypothermic Storage of Feline Kidneys for Transplantation: Successful Ex Vivo Storage Up to 7 Hours

Objective—To describe the effect of hypothermic storage on transplanted feline kidneys.
Study Design—Kidneys were stored in University of Wisconsin (UW) sodium gluconate (n = 3) or phosphate-buffered sucrose (n = 5) solutions before transplantation.
Animal Population—Eight cats with renal failure and seven normal cats as kidney donors.
Methods—Kidneys were perfused through the renal artery with cold (10°C) storage solution and immersed in the solution on ice until transplantation.
Results—Mean ex vivo storage time was 4.8 ± 0.36 hours (range, 3.5 to 7 hours). Seven recipient cats survived surgery. Five of the cats had decreased serum creatinine concentrations from a mean of 8.2 mg/dL (range, 4.0 to 15.8 mg/dL) preoperatively to 1.7 mg/dL (range, 1.3 to 2.2 mg/dL) within 4 days of surgery. In one cat, serum creatinine concentration dropped from 15.1 to 3.7 mg/dL in 3 days, but the cat developed a ureteral stricture that required revision. One graft did not function, and the cat died on day 19. The mean postoperative survival time of cats that were discharged from the hospital (n = 6) was 254 days (range, 49 to 717 days) at the time of this report. Long-term renal function (>60 days postoperatively; n = 5) was excellent with mean serum creatinine concentrations of 1.6 ± 0.15 mg/dL.
Conclusions—Hypothermic storage is feasible for short-term preservation of feline kidneys.
The maximal length of feasible storage remains unknown.
Clinical Relevance—Hypothermia protects against ischemia-induced nephron loss during ex vivo manipulation of the allograft and allows longer safe vascular anastomosis times. Short-term hypothermic storage also provides time to accommodate modifications in scheduling or anesthetic management of the recipient operation.     

Observations on Uterine Prolapse in Beef Cattle

Serum samples were obtained from 26 beef cows with uterine prolapse and from 15 with minor dystocia (controls). The serum of animals with uterine prolapse had significantly lower calcium concentration (mean ± S.D. = 8,22 ± 0,69 mg/dL, P≤0,01), higher phosphorus concentration (mean ± S.D. = 4,78 ± 1,75 mg/dL, P≤0,05) and lower calcium to phosphorus ratios (mean ± S.D. = 1,99 ± 0,88, P≤0,01) than for the control animals (means ± S.D. = 8,91 ± 0,75 mg/dL, 3,54 ± 1,41 mg/dL and 2,99 ± 1,41 respectively). Mild hypocalcemia (6,9 mg/dL-7,9 mg/dL) was present in 11 (42,3%) of the cows with prolapse as compared to only one (6,7%) of the controls. Hypophosphatemia was present in 11 (42,3%) of the animals with prolapse and in ten (66,7%) of the controls.

Eighteen (69,2%) of the animals with prolapse were alert and ambulatory when treated and 15 (57,7%) were known to have required help to deliver the calf. Of the cattle group with uterine prolapse, 14 (53,8%) were two years old, six (23,1%) were three years old, and six (23,1%) were four years of age or older.

It was concluded that mild hypocalcemia and some degree of dystocia were associated with the uterine prolapses. The phosphorus results were equivocal but the high incidence of hypophosphatemia may reflect a phosphorus deficient diet.

     

Transient clinical diabetes mellitus in cats: 10 cases (1989-1991)

Medical records of 10 cats with transient clinical diabetes mellitus were reviewed. At the time diabetes was diagnosed, clinical signs included polyuria and polydipsia (10 cats), weight loss (8 cats), polyphagia (3 cats), lethargy (2 cats), and inappetence (1 cat). Mean (+/- SD) fasting blood glucose concentration was 454 +/- 121 mg/dL, mean blood glucose concentration during an 8-hour period (MBG/8 hours) was 378 +/- 72 mg/dL, and glycosuria and trace ketonuria were identified in 10 and 5 cats, respectively. Baseline serum insulin concentration was undetectable (6 cats) or within the reference range (4 cats) and serum insulin concentration did not increase after i.v. glucagon administration in any cat. Insulin-antagonistic drugs were being administered to 5 cats and concurrent disorders were identified in all cats. Management of diabetes included administration of glipizide (6 cats), insulin (3 cats), or both (1 cat), discontinuation of insulin-antagonistic drugs, and treatment of concurrent disorders. Insulin and glipizide treatment was discontinued 4-16 weeks (mean, 7 weeks) after the initial diagnosis of diabetes was confirmed. At the time treatment for diabetes was discontinued, clinical signs had resolved, mean fasting blood glucose concentration was 102 +/- 48 mg/dL, MBG/ 8 hours was 96 +/- 32 mg/dL, glycosuria and ketonuria were not identified in any cat, and concurrent disorders (except mild renal insufficiency in 1 cat) had resolved. Significant (P < .05) increases occurred in postglucagon serum insulin concentrations, insulin peak response, and total insulin secretion, compared with values obtained when clinical diabetes was diagnosed. Histologic abnormalities were identified in pancreatic islets of 5 cats in which pancreatic biopsies were obtained and included decreased number of islets (4 cats), islet amyloidosis (3 cats), and vacuolar degeneration of islet cells (3 cats). Mean beta cell density was significantly (P < .001) decreased in diabetic cats compared with control cats (1.4 +/- 0.7 versus 2.6 +/- 0.5%, respectively). Cells within islets stained positive for insulin, however, the number of insulin-staining cells per islet and the intensity of insulin staining were decreased in 5 and 2 cats, respectively. Clinical diabetes had not recurred in 1 cat after 6 years, in 4 cats lost to follow-up after 1.5, 1.5, 2.0, and 2.5 years, and in 2 cats that died 6 months and 5.5 years after clinical diabetes resolved. Clinical diabetes recurred in 3 cats after 6 months, 14 months, and 3.4 years, respectively. These findings suggest that cats with transient clinical diabetes have pancreatic islet pathology, including decreased beta cell density, and that treatment of diabetes and concurrent disorders results in improved beta cell function, reestablishment of euglycemia, and a transition from a clinical to subclinical diabetic state.     

Hypercalcemia in cats: a retrospective study of 71 cases (1991-1997)

A retrospective study was conducted to characterize the diseases, clinical findings, and clinicopathologic and ultrasonographic findings associated with hypercalcemia (serum calcium concentration >11 mg/dL) in 71 cats presented to North Carolina State University Veterinary Teaching Hospital. The 3 most common diagnoses were neoplasia (n = 21), renal failure (n = 18), and urolithiasis (n = 11). Primary hyperparathyroidism was diagnosed in 4 cats. Lymphoma and squamous cell carcinoma were the most frequently diagnosed tumors. Calcium oxalate uroliths were diagnosed in 8 of 11 cats with urolithiasis. Cats with neoplasia had a higher serum calcium concentration (13.5 ± 2.5 mg/dL) than cats with renal failure or urolithiasis and renal failure (11.5 ± 0.4 mg/dL; P <.03). Serum phosphorus concentration was higher in cats with renal failure than in cats with neoplasia ( P < .004). Despite the fact that the majority of cats with uroliths were azotemic, their serum urea nitrogen and creatinine concentrations and urine specific gravity differed from that of cats with renal failure. Additional studies are warranted to determine the underlying disease mechanism in the cats we identified with hypercalcemia and urolithiasis. We also identified a small number of cats with diseases that are not commonly reported with hypercalcemia. Further studies are needed to determine whether an association exists between these diseases and hypercalcemia, as well as to characterize the underlying pathophysiologic mechanism for each disease process.     

Acute intrinsic renal failure in cats: 32 cases (1997-2004)

OBJECTIVE: To determine patient demographics, clinicopathologic findings, and outcome associated with naturally acquired acute intrinsic renal failure (ARF) in cats. DESIGN: Retrospective case series. ANIMALS: 32 cats with ARF. PROCEDURES: Cats were considered to have ARF if they had acute onset of clinical signs (< 7 days), serum creatinine concentration > 2.5 mg/dL (reference range, 0.8 to 2.3 mg/dL) and BUN > 35 mg/dL (reference range, 15 to 34 mg/dL) in conjunction with urine specific gravity < 1.025 or with anuria or increasing serum creatinine concentration despite fluid therapy and normal hydration status, and no signs of chronic renal disease. Cases were excluded if cats had renal calculi or renal neoplasia. RESULTS: Causes of ARF included nephrotoxins (n = 18 cats), ischemia (4), and other causes (10). Eighteen cats were oliguric. For each unit (mEq/L) increase in initial potassium concentration, there was a 57% decrease in chance of survival. Low serum albumin or bicarbonate concentration at initial diagnosis was a negative prognostic indicator for survival. Initial concentrations of BUN, serum creatinine, and other variables were not prognostic. Seventeen (53%) cats survived, of which 8 cats had resolution of azotemia and 9 cats were discharged from the hospital with persistent azotemia. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that survival rates of cats with ARF were similar to survival rates in dogs and that residual renal damage persisted in approximately half of cats surviving the initial hospitalization.     

Serum IgG Concentrations after Intravenous Serum Transfusion in a Randomized Clinical Trial in Dairy Calves with Inadequate Transfer of Colostral Immunoglobulins

Background: Plasma transfusions have been used clinically in the management of neonates with failure of passive transfer. No studies have evaluated the effect of IV serum transfusions on serum IgG concentrations in dairy calves with inadequate transfer of passive immunity.
Hypothesis: A commercially available serum product will increase serum immunoglobulin concentration in calves with inadequate transfer of colostral immunoglobulins.
Animals: Thirty-two Jersey and Jersey-Holstein cross calves with inadequate colostral transfer of immunoglobulins (serum total protein <5.0 g/L).
Methods: Thirty-two calves were randomly assigned to either control (n = 15) or treated (n = 17) groups. Treated calves received 0.5 L of a pooled serum product IV. Serum IgG concentrations before and after serum transfusion were determined by radial immunodiffusion.
Results: Serum protein concentrations increased from time 0 to 72 hours in both control and transfused calves and the difference was significant between the control and treatment groups ( P < .001). Mean pre- and posttreatment serum IgG concentrations in control and transfused calves did not differ significantly. Median serum IgG concentrations decreased from 0 to 72 hours by 70 mg/dL in control calves and increased over the same time interval in transfused calves by 210 mg/dL. The difference was significant between groups ( P < .001). The percentage of calves that had failure of immunoglobulin transfer 72 hours after serum transfusion was 82.4%.
Conclusions and Clinical Importance: Serum administration at the dosage reported did not provide adequate serum IgG concentrations in neonatal calves with inadequate transfer of colostral immunoglobulins.     

Effect of specimen collection and storage on blood glucose and lactate concentrations in healthy,hyperthyroid and diabetic cats

Abstract: The objective of this study was to compare and investigate differences in glucose and lactate concentrations in sodium fluoride/potassium oxalate (NaF/Ox) plasma and serum in healthy cats and cats with metabolic disease. Glucose and lactate concentrations were determined in routinely processed serum and NaF/Ox plasma obtained from healthy (n = 30), hyperthyroid (n = 27) and diabetic (n = 30) cats, and in samples from 6 healthy cats stored at 25°C or 4°C for 0,1, 2, 4, or 8 hours. The packed cell volume (PCV) of blood collected in NaF/Ox was compared with that of blood collected in EDTA. Mean glucose concentration was significantly (P < .05) lower in NaF/Ox plasma than in serum in all groups of cats, by 0.7–2.5 mmol/L (11–45 mg/dL); the difference was greater in cats with hyperglycemia. Mean lactate concentration was significantly higher in serum than in NaF/Ox plasma in all groups of cats, by 0.4–1.2 mmol/L (3.6–10.8 mg/dL); the difference was greater in hyperthyroid and diabetic cats. In vitro, only serum stored on the clot for ≥ 1hour at 25°C had significantly lower glucose and higher lactate concentrations. The PCV of NaF/Ox-anticoagulated blood was lower than that of EDTA-anticoagulated blood, by 7.0%± 1.4% (P<.01). In conclusion, collection of feline blood in NaF/Ox was necessary to prevent in vitro increases in lactate concentration; however, NaF/Ox artifactually decreased plasma glucose concentration because of RBC shrinkage. The PCV should not be determined on blood collected in NaF/Ox.     

Comparison of 3 techniques for ureteroneocystostomy in cats

OBJECTIVE: To compare 3 techniques for ureteroneocystostomy in cats. STUDY DESIGN: Experimental surgical study. ANIMALS: Fifteen adult cats. METHODS: Cats (15) had ureteroneocystostomy with ureteronephrectomy of the contralateral kidney: 5 cats had an intravesical mucosal apposition technique (modified Leadbetter-Politano; intravesical-MA group), 5 cats had extravesical ureteroneocystostomy (modified Lich Gregoir) using a simple continuous suture pattern (extravesical-SC group) and 5 cats had an extravesical technique using a simple interrupted suture pattern (extravesical-SI group). Renal function was evaluated by measuring serum creatinine concentration. Ultrasonographic assessment of the kidney and ureteroneocystostomy site was performed the day after surgery, twice weekly for 3 weeks and once weekly for the remainder of the study. Cats were euthanatized 50 days after surgery. The kidney and ureter removed at surgery, the remaining kidney, ureter, ureteroneocystostomy site, and bladder were examined histologically. RESULTS: Two extravesical-SC cats were euthanatized because of azotemia and uroabdomen, and 1 died acutely at day 4 for unknown reasons. In the intravesical-MA and extravesical-SI cats, the serum creatinine concentration increased after surgery, peaking at a mean (+/-SD) of 9.4+/-2.4 mg/dL and 4.9+/-3.3 mg/dL on day 3, and decreasing to 3.4+/-5.7 mg/dL and 1.5+/-0.4 mg/dL on day 7, respectively. The extravesical-SI technique was associated with consistently lower serum creatinine concentrations for the first week after surgery compared with the other techniques. The mean serum creatinine concentration was within the reference range in cats in the intravesical-MA and extravesical-SI groups by days 10 and 5, respectively. Renal pelvic dilatation occurred in all cats but resolved more rapidly in cats after extravesical techniques. There was no significant difference in serum creatinine concentrations or renal pelvic dilation between the intravesical-MA and extravesical-SI techniques. Bladder mass height at the anastomosis site was significantly larger and persisted for longer with intravesical-MA technique. CONCLUSION: An extravesical-SI technique is seemingly the choice for ureteroneocystostomy in cats with undilated ureters. Renal pelvic dilation on ultrasound examination should be expected after ureteroneocystostomy in cats. CLINICAL RELEVANCE: An extravesical ureteroneocystostomy technique using a simple interrupted pattern for anastomosis should be considered in cats undergoing renal transplantation.     

Red Blood Cell Phosphate Concentration and Osmotic Resistance During Dietary Phosphate Depletion in Dairy Cows

Background

Hypophosphatemia in early lactating dairy cows has been implicated as primary cause for postparturient hemoglobinuria in cattle. Decreased availability of phosphorus has been proposed to reduce adenosine triphosphate synthesis of erythrocytes and thereby reduce osmotic resistance of these cells.

Hypothesis/Objectives

To study the effect of phosphorus depletion on the phosphate concentration ([Pi]) in plasma and erythrocytes and the osmotic resistance of erythrocytes and to determine the association between plasma [Pi] and erythrocyte [Pi].

Animals

Ten healthy midlactating dairy cows in their 3rd to 5th lactation.

Methods

Prospective study. Dietary phosphorus depletion for 5 weeks followed by phosphorus supplementation. Plasma and erythrocyte [Pi] and erythrocyte osmotic resistance were measured. Four cows underwent continuous dextrose infusion at the end of phosphate depletion to exacerbate hypophosphatemia.

Results

Dietary P depletion resulted in a marked decline of the plasma [Pi] from 4.1 ± 1.0 mg/dL to a nadir of 1.7 ± 0,5 mg/dL, but did not alter erythrocyte [Pi] or osmotic resistance. Similarly, dextrose infusion induced a decline of the plasma [Pi] from 2.4 ± 0.5 mg/dL to 1.5 ± 0.5 mg/dL, but had no effect on erythrocyte [Pi] or osmotic resistance.

Conclusions and Clinical Importance

In cattle, marked hypophosphatemia induced by dietary P depletion was neither associated with a decline in erythrocyte [Pi] nor with decreased osmotic resistance of erythrocytes. Phosphorus depletion alone is therefore unlikely to cause intravascular hemolysis and the plasma [Pi] is an unreliable index for the intracellular [Pi] of erythrocytes.     

A Double‐blind,Placebo‐controlled,Multicenter, Prospective,Randomized Study of Beraprost Sodium Treatment for Cats with Chronic Kidney Disease

Background

Chronic kidney disease (CKD) is a common progressive and irreversible disease in cats. The efficacy and safety of beraprost sodium (BPS) in cats with CKD have not been evaluated.

Hypothesis/Objectives

To evaluate the efficacy and safety of BPS in the treatment of cats with CKD, as compared to placebo.

Animals

Seventy‐four client‐owned cats with naturally occurring CKD.

Methods

Double‐blind, placebo‐controlled, multicenter, prospective, randomized trial. The cats received BPS (55 μg/cat) or a placebo PO q12 h for 180 days. The primary endpoint was prospectively defined as a change in the serum creatinine (sCr), serum phosphorus‐to‐calcium ratio or urine specific gravity (USG).

Results

The sCr increased significantly (P = 0.0030) in the placebo group (mean ± SD: 2.8 ± 0.7 to 3.2 ± 1.3 mg/dL) but not in the BPS group (2.4 ± 0.7 to 2.5 ± 0.7 mg/dL). The difference between the groups at day 180 was significant (0.8 mg/dL, 95% CI: 0.2 to 1.3 mg/dL, P = 0.0071). The serum phosphorus‐to‐calcium ratio was significantly (P = 0.0037) increased in the placebo group (0.46 ± 0.10 to 0.52 ± 0.21 mg/dL) but not in the BPS group (0.50 ± 0.08 to 0.51 ± 0.11 mg/dL). There was no significant change in the USG in either group. An adverse event judged as being treatment‐related included vomiting that occurred in 1 case in the placebo group. No clinically relevant change was observed in the CBC and other blood chemistry tests.

Conclusions and Clinical Importance

Beraprost sodium treatment was well tolerated and safe in cats with CKD. BPS inhibited the reduction in renal filtration function as measured by sCr increase.     

Applications and Outcome of Hemodialysis in Cats: A Review of 29 Cases

Hemodialysis (HO) has been used in the management of renal failure in dogs, but its feasibility has not been reported for uremic cats. Therefore, we investigated the technical possibility, efficacy, and complications of intermittent HD in cats with severe uremia. A total of 160 HD treatments were performed on 29 cats with acute renal failure (ARF) (n = 15), chronic renal failure (CRF) (n = 6), or acute on CRF (n =8) between November 1993 and June 1996. Hemodialysis treatments were performed with transcutaneous dialysis catheters using a bicarbonate-based delivery system, sodium modeling, and volumetric-controlled ultrafiltration. Presenting serum chemistries (mean ± SD) for all cats were creatinine, 16.4 ± 7.5 mg/dL; blood urea nitrogen (BUN), 229 ± 87 mg/dL; phosphate, 15.4 ± 5.4 mg/dL; potassium, 6.0 ±1.6 mEq/L; and HCO^-₃, 16.0 ± 4.4 mEq/L. For intensive HD treatments, pre-HD versus post-HD creatinine changed from 10.3 ± 4.4 to 1.6 ± 0.9 mg/dL and BUN from 105 ± 33 to 8 ±10 mg/dL. One or more adverse events occurred during 111 (69%) treatments. Dialysis-related events included hypotension, dialysis dysequilibrium, clotting, and bleeding. Nine of 15 (60%) cats with ARF and 1 cat with CRF recovered sufficiently to survive without ongoing need for HD. For the remaining cats, the proximate causes of death were dialysis related in 9 cats, uremia related in 6 cats, and iatrogenic or unknown in 4 cats. Hemodialysis is technically feasible and effectively controls the biochemical disturbances of uremic cats. It is especially valuable for the management of severe ARF, permitting recovery in a large number of cats refractory to conventional therapy. Technical complications and chronic debility, however, may limit its usefulness for cats with advanced CRF.     

Severe hypophosphatemia associated with diabetes mellitus in six dogs and one cat

Severe hypophosphatemia was found in 6 diabetic dogs and in one diabetic cat. The cat suffered from hemolysis, and one dog had seizures, both apparently as a result of the severe hypophosphatemia. Clinical signs were not determined solely by the serum concentration of phosphorus, as seen in 5 other patients that did not have signs of disease despite similar serum phosphorus concentrations.     

Hemolytic anemia and red blood cell metabolic disorder attributable to low phosphorus intake in cows

Hypophosphatemia was induced in 2 cows by reducing phosphorus content in their feed after parturition. Serum inorganic phosphorus (Pi) values decreased to 1 mg/dl within 10 days after parturition; and RBC adenosine 5'-triphosphate (ATP) and reduced glutathione values decreased to 50 and 70% of baseline values, respectively. Methemoglobin concentration was moderately higher than normal. These changes preceded the onset of hemolysis, and anemia progressed with decreases in PCV, hemoglobin concentration, and RBC counts. Serum Pi resumed its normal value when anemia was most severe. This RBC disorder was confirmed to be characteristic of hemolytic anemia in cows resulting from hypophosphatemia. The RBC glycolytic intermediates, total triose phosphate (combined glyceraldehyde-3-phosphate and dihydroxyacetone phosphate content) and fructose-1,6-diphosphate, greatly increased in vivo and in vitro with decreases in serum or plasma Pi and RBC ATP. From our results, we concluded that inadequate Pi in the plasma impairs the function and viability of RBC by hindering the production of ATP via disturbance of reactions at the glyceraldehyde-3-phosphate dehydrogenase step.     

A Retrospective Study of the Use of Total Parenteral Nutrition in Dogs and Cats

The records of all dogs and cats receiving total parenteral nutrition (TPN) over a 43-month period were examined retrospectively. Dextrose, amino acids, lipids, electrolytes, and vitamins were administered by central venous catheter according to published nutrient recommendations; 72 dogs and 12 cats were studied, accounting for 380 patient days of TPN. Duration of TPN administration was 1–14 days with a mean of 4.5 days. Most animals required TPN because of gastrointestinal dysfunction, and more than half of them gained weight during TPN administration. Mechanical complications were frequent. Metabolic complications, especially lipid and glucose intolerance, were also commonly seen. Septic complications were the least frequently encountered, but resulted in patient morbidity and may have contributed to mortality. Most animals receiving TPN were returned to enteral nutrition and discharged. For critically ill animals unable to tolerate enteral alimentation, TPN can be supportive therapy in the treatment of the primary disease.     

Use of continuous renal replacement therapy for treatment of dogs and cats with acute or acute-on-chronic renal failure: 33 cases (2002–2006)

Objective: To describe the indications, clinical features, outcomes and complications associated with use of continuous renal replacement therapy (CRRT) in 17 client-owned dogs and 16 client-owned cats with acute or acute-on-chronic renal failure refractory to aggressive medical management.
Series summary: Twenty-nine percent of dogs and 44% of cats had evidence of pre-existing chronic kidney disease (CKD). Median duration of CRRT was 16.3 hours (range 0.3–83.0 hours) in dogs and 11.5 hours (range 1.0–35.5 hours) in cats. Median canine blood urea nitrogen (BUN) improved from 41.0 mmol/L (115.0 mg/dL) to 11.8 mmol/L (33.0 mg/dL) and creatinine from 636.5 mmol/L (7.2 mg/dL) to 274 mmol/L (3.1 mg/dL). Median feline BUN improved from 46.4 mmol/L (130 mg/dL) to 13.9 mmol/L (39.0 mg/dL) and creatinine from 1069.6 mmol/L (12.1 mg/dL) to 291.7 mmol/L (3.3 mg/dL). Metabolic acidosis resolved in 80% of affected dogs and 71% of affected cats. Hyperkalemia resolved in 100% of affected dogs and 88% of affected cats. Complications noted with CRRT included iatrogenic hypokalemia, iatrogenic metabolic alkalosis, clinical hypocalcemia, total hypercalcemia, filter clotting, anemia, hypothermia, and neurologic complications. Forty-one percent of dogs and 44% of cats survived to discharge. No dogs and only 1 cat developed newly diagnosed CKD.
New or unique information provided: CRRT can be a viable option for the management of acute or acute-on-chronic renal failure in dogs and cats that are refractory to aggressive medical management. The frequency of complications associated with CRRT in this study warrants further experience with this modality before its widespread use can be recommended.     

Hyperlipemia and Ketonuria in an Alpaca and a Llama

An alpaca and a llama in late stages of gestation were evaluated for lethargy, anorexia, and recumbency. Both camelids had cloudy, white, turbid serum, elevated serum triglyceride (1564, 5658 mg/dL, respectively) and cholesterol (158, 297 mg/dL, respectively) concentrations, and ketonuria. Signs of fetal stress were evident ultrasonographically in the alpaca, and a live cria was delivered by Cesarean section performed under general anesthesia. The alpaca developed severe metabolic acidosis, hepatic lipidosis, and acute renal failure secondary to renal lipidosis and died 36 hours after admission despite medical therapy. Histopathology revealed renal and hepatic lipidosis and neutrophilic pancreatitis. The cria died 72 hours after birth. The llama responded to IV electrolyte, dextrose, and regular crystalline insulin therapy. The pregnancy was maintained, and the llama was discharged from the hospital 20 days after admission. Two months after discharge, the llama gave birth to a live, 5 kg cria. Findings of hypertriglyceridemia, hypercholesterolemia, elevated sorbitol dehydrogenase activity, metabolic acidosis, azotemia, and ketonuria occurred in these two camelids. Based on this report, camelids appear to be similar to both horses and cattle in their response to severe energy imbalances in late gestation.     

Field Safety and Efficacy of Protamine Zinc Recombinant Human Insulin for Treatment of Diabetes Mellitus in Cats

Background: This study describes the efficacy of a new protamine zinc recombinant human insulin (PZIR) preparation for treating diabetic cats. Objective: To evaluate effects of PZIR on control of glycemia in cats with newly diagnosed or poorly controlled diabetes mellitus. Animals: One hundred and thirty‐three diabetic cats 120 newly diagnosed and 13 previously treated. Methods: Prospective, uncontrolled clinical trial. Cats were treated with PZIR twice daily for 45 days. Control of glycemia was assessed on days 7, 14, 30, and 45 by evaluation of change in water consumption, frequency of urination, appetite, and body weight, serum fructosamine concentration, and blood glucose concentrations determined 1, 3, 5, 7, and 9 hours after administration of PZIR. Adjustments in dosage of PZIR were made as needed to control glycemia. Results: PZIR administration resulted in a significant decrease in 9‐hour mean blood glucose (199 ± 114 versus 417 ± 83 mg/dL, X± SD, P < .001) and serum fructosamine (375 ± 117 versus 505 ± 96 μmol/L, P < .001) concentration and a significant increase in mean body weight (5.9 ± 1.4 versus 5.4 ± 1.5 kg, P= .017) in 133 diabetic cats at day 45 compared with day 0, respectively. By day 45, polyuria and polydipsia had improved in 79% (105 of 133), 89% (118 of 133) had a good body condition, and 9‐hour mean blood glucose concentration, serum fructosamine concentration, or both had improved in 84% (112 of 133) of the cats compared with day 0. Hypoglycemia (<80 mg/dL) was identified in 151 of 678, 9‐hour serial blood glucose determinations and in 85 of 133 diabetic cats. Hypoglycemia causing clinical signs was confirmed in 2 diabetic cats. Conclusions and Clinical Relevance: PZIR is effective for controlling glycemia in diabetic cats and can be used as an initial treatment or as an alternative treatment in diabetic cats that do not respond to treatment with other insulin preparations.